From db20e8f3ed96cbcac3156cbd2f34795baa595316 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Jos=C3=A9=20Fonseca?= Date: Sat, 4 Dec 2010 13:11:39 +0000 Subject: [PATCH] Bumple libpng source. --- CMakeLists.txt | 48 +- libpng/ANNOUNCE | 65 + libpng/CHANGES | 2689 +++++++++++++++++++++++++++++ libpng/LICENSE | 111 ++ libpng/README | 257 +++ libpng/TODO | 31 + libpng/libpng.txt | 3352 ++++++++++++++++++++++++++++++++++++ libpng/png.c | 918 ++++++++++ libpng/png.h | 2699 +++++++++++++++++++++++++++++ libpng/pngconf.h | 1540 +++++++++++++++++ libpng/pngerror.c | 402 +++++ libpng/pngget.c | 925 ++++++++++ libpng/pngmem.c | 611 +++++++ libpng/pngpread.c | 1765 +++++++++++++++++++ libpng/pngpriv.h | 954 ++++++++++ libpng/pngread.c | 1361 +++++++++++++++ libpng/pngrio.c | 163 ++ libpng/pngrtran.c | 4203 +++++++++++++++++++++++++++++++++++++++++++++ libpng/pngrutil.c | 3379 ++++++++++++++++++++++++++++++++++++ libpng/pngset.c | 1167 +++++++++++++ libpng/pngtrans.c | 677 ++++++++ libpng/pngwio.c | 241 +++ libpng/pngwrite.c | 1457 ++++++++++++++++ libpng/pngwtran.c | 566 ++++++ libpng/pngwutil.c | 2786 ++++++++++++++++++++++++++++++ 25 files changed, 32359 insertions(+), 8 deletions(-) create mode 100644 libpng/ANNOUNCE create mode 100644 libpng/CHANGES create mode 100644 libpng/LICENSE create mode 100644 libpng/README create mode 100644 libpng/TODO create mode 100644 libpng/libpng.txt create mode 100644 libpng/png.c create mode 100644 libpng/png.h create mode 100644 libpng/pngconf.h create mode 100644 libpng/pngerror.c create mode 100644 libpng/pngget.c create mode 100644 libpng/pngmem.c create mode 100644 libpng/pngpread.c create mode 100644 libpng/pngpriv.h create mode 100644 libpng/pngread.c create mode 100644 libpng/pngrio.c create mode 100644 libpng/pngrtran.c create mode 100644 libpng/pngrutil.c create mode 100644 libpng/pngset.c create mode 100644 libpng/pngtrans.c create mode 100644 libpng/pngwio.c create mode 100644 libpng/pngwrite.c create mode 100644 libpng/pngwtran.c create mode 100644 libpng/pngwutil.c diff --git a/CMakeLists.txt b/CMakeLists.txt index 443bb88..c8848d3 100644 --- a/CMakeLists.txt +++ b/CMakeLists.txt @@ -14,9 +14,15 @@ endif (NOT CMAKE_BUILD_TYPE) find_package (PythonInterp REQUIRED) find_package (OpenGL REQUIRED) -find_package (ZLIB) -find_package (DirectX) +if (NOT WIN32) + # Always use the bundled zlib and libpng sources on Windows to make it easy + # to deploy the wrappers DLLs + find_package (ZLIB) + find_package (PNG) +else (NOT WIN32) + find_package (DirectX) +endif (NOT WIN32) find_package (GLUT) @@ -57,7 +63,10 @@ else () endif () # Use bundled ZLIB if system one can't be found -if (NOT ZLIB_FOUND) +if (ZLIB_FOUND) + include_directories (${ZLIB_INCLUDE_DIRS}) + link_libraries (${ZLIB_LIBRARIES}) +else (ZLIB_FOUND) add_library (zlib STATIC zlib/adler32.c zlib/compress.c @@ -72,13 +81,36 @@ if (NOT ZLIB_FOUND) zlib/inftrees.c zlib/inffast.c ) - include_directories (zlib) link_libraries (zlib) -else (NOT ZLIB_FOUND) - include_directories (${ZLIB_INCLUDE_DIRS}) - link_libraries (${ZLIB_LIBRARIES}) -endif (NOT ZLIB_FOUND) +endif (ZLIB_FOUND) + +# Use bundled LIBPNG if system one can't be found +if (PNG_FOUND) + include_directories (${PNG_INCLUDE_DIR}) + add_definitions (${PNG_DEFINITIONS}) + link_libraries (${PNG_LIBRARIES}) +else (PNG_FOUND) + add_library (png STATIC + libpng/png.c + libpng/pngerror.c + libpng/pngget.c + libpng/pngmem.c + libpng/pngpread.c + libpng/pngread.c + libpng/pngrio.c + libpng/pngrtran.c + libpng/pngrutil.c + libpng/pngset.c + libpng/pngtrans.c + libpng/pngwio.c + libpng/pngwrite.c + libpng/pngwtran.c + libpng/pngwutil.c + ) + include_directories (libpng) + link_libraries (png) +endif (PNG_FOUND) include_directories (${CMAKE_CURRENT_SOURCE_DIR}) diff --git a/libpng/ANNOUNCE b/libpng/ANNOUNCE new file mode 100644 index 0000000..f160172 --- /dev/null +++ b/libpng/ANNOUNCE @@ -0,0 +1,65 @@ + +Libpng 1.4.4 - September 23, 2010 + +This is a public release of libpng, intended for use in production codes. + +Files available for download: + +Source files with LF line endings (for Unix/Linux) and with a +"configure" script + + libpng-1.4.4.tar.xz (LZMA-compressed, recommended) + libpng-1.4.4.tar.gz + libpng-1.4.4.tar.bz2 + +Source files with CRLF line endings (for Windows), without the +"configure" script + + lpng144.zip + lpng144.7z + +Other information: + + libpng-1.4.4-README.txt + libpng-1.4.4-LICENSE.txt + +Changes since the last public release (1.4.3): + Removed extraneous new_push_process_row.c file. + Revised the "SEE ALSO" style of libpng.3, libpngpf.3, and png.5 + Removed some newly-added TAB characters from pngpread.c. + Fixed some indentation in pngpread.c and pngrutil.c + Changed "extern PNG_EXPORT" to "PNG_EXPORT" in png.h (Jan Nijtmans) + Changed "extern" to "PNG_EXTERN" in pngpriv.h (except for the 'extern "C" {') + Put "#ifndef PNG_EXTERN, #endif" around "#define PNG_EXTERN" in pngpriv.h + Added -DNO_PNG_SNPRINTF to CFLAGS in scripts/makefile.dj2 + Moved the definition of png_snprintf() outside of the enclosing + #ifdef blocks in pngconf.h + Made a special case "#define PNGAPI" in pngconf.h for WATCOM. + Removed reference to cbuilder5/* from Makefile.in and Makefile.am + Updated the read macros and functions from 1.5.0beta38. + Updated projects/visualc71 so it can find scripts/pnglibconf.h + Removed unused png_mem_* defines from pngconf.h. + Correct use of _WINDOWS_ in pngconf.h + Don't try to use version-script with cygwin/mingw. + Revised contrib/gregbook to work under cygwin/mingw. + Updated prebuilt aclocal.m4 and ltmain.sh + Add .dll.a to the list of extensions to be symlinked by Makefile.am (Yaakov) + Updated CMakelists.txt to use CMAKE_INSTALL_LIBDIR variable; useful for + installing libpng in /usr/lib64 (Funda Wang). + Revised CMakeLists.txt to put the man pages in share/man/man* not man/man* + Revised CMakeLists.txt to make symlinks instead of copies when installing. + Moved "#include pngusr.h" ahead of PNG_USER_PRIVATEBUILD test in pngconf.h + Eliminated a deprecated reference to png_ptr->io_ptr in pngtest.c + Eliminated new unnecessary #if tests regarding the sCAL chunk from pngrutil.c + Updated the xcode project to work with libpng-1.4.x and added iOS targets + for simulator and device (Philippe Hausler). + Revised autogen.sh to recognize and use $AUTOCONF, $AUTOMAKE, $AUTOHEADER, + $AUTOPOINT, $ACLOCAL and $LIBTOOLIZE + Rebuilt configure scripts with automake-1.11.1 instead of automake-1.11. + Removed unused mkinstalldirs file. + +Send comments/corrections/commendations to glennrp at users.sourceforge.net +or to png-mng-implement at lists.sf.net (subscription required; visit +https://lists.sourceforge.net/lists/listinfo/png-mng-implement). + +Glenn R-P diff --git a/libpng/CHANGES b/libpng/CHANGES new file mode 100644 index 0000000..271ca1a --- /dev/null +++ b/libpng/CHANGES @@ -0,0 +1,2689 @@ +#if 0 +libpng_changes(){ /* +CHANGES - changes for libpng + +version 0.2 + added reader into png.h + fixed small problems in stub file + +version 0.3 + added pull reader + split up pngwrite.c to several files + added pnglib.txt + added example.c + cleaned up writer, adding a few new transformations + fixed some bugs in writer + interfaced with zlib 0.5 + added K&R support + added check for 64 KB blocks for 16 bit machines + +version 0.4 + cleaned up code and commented code + simplified time handling into png_time + created png_color_16 and png_color_8 to handle color needs + cleaned up color type defines + fixed various bugs + made various names more consistent + interfaced with zlib 0.71 + cleaned up zTXt reader and writer (using zlib's Reset functions) + split transformations into pngrtran.c and pngwtran.c + +version 0.5 + interfaced with zlib 0.8 + fixed many reading and writing bugs + saved using 3 spaces instead of tabs + +version 0.6 + added png_large_malloc() and png_large_free() + added png_size_t + cleaned up some compiler warnings + added png_start_read_image() + +version 0.7 + cleaned up lots of bugs + finished dithering and other stuff + added test program + changed name from pnglib to libpng + +version 0.71 [June, 1995] + changed pngtest.png for zlib 0.93 + fixed error in libpng.txt and example.c + +version 0.8 + cleaned up some bugs + added png_set_filler() + split up pngstub.c into pngmem.c, pngio.c, and pngerror.c + added #define's to remove unwanted code + moved png_info_init() to png.c + added old_size into png_realloc() + added functions to manually set filtering and compression info + changed compression parameters based on image type + optimized filter selection code + added version info + changed external functions passing floats to doubles (k&r problems?) + put all the configurable stuff in pngconf.h + enabled png_set_shift to work with paletted images on read + added png_read_update_info() - updates info structure with + transformations + +version 0.81 [August, 1995] + incorporated Tim Wegner's medium model code (thanks, Tim) + +version 0.82 [September, 1995] + [unspecified changes] + +version 0.85 [December, 1995] + added more medium model code (almost everything's a far) + added i/o, error, and memory callback functions + fixed some bugs (16 bit, 4 bit interlaced, etc.) + added first run progressive reader (barely tested) + +version 0.86 [January, 1996] + fixed bugs + improved documentation + +version 0.87 [January, 1996] + fixed medium model bugs + fixed other bugs introduced in 0.85 and 0.86 + added some minor documentation + +version 0.88 [January, 1996] + fixed progressive bugs + replaced tabs with spaces + cleaned up documentation + added callbacks for read/write and warning/error functions + +version 0.89 [July, 1996] + added new initialization API to make libpng work better with shared libs + we now have png_create_read_struct(), png_create_write_struct(), + png_create_info_struct(), png_destroy_read_struct(), and + png_destroy_write_struct() instead of the separate calls to + malloc and png_read_init(), png_info_init(), and png_write_init() + changed warning/error callback functions to fix bug - this means you + should use the new initialization API if you were using the old + png_set_message_fn() calls, and that the old API no longer exists + so that people are aware that they need to change their code + changed filter selection API to allow selection of multiple filters + since it didn't work in previous versions of libpng anyways + optimized filter selection code + fixed png_set_background() to allow using an arbitrary RGB color for + paletted images + fixed gamma and background correction for paletted images, so + png_correct_palette is not needed unless you are correcting an + external palette (you will need to #define PNG_CORRECT_PALETTE_SUPPORTED + in pngconf.h) - if nobody uses this, it may disappear in the future. + fixed bug with Borland 64K memory allocation (Alexander Lehmann) + fixed bug in interlace handling (Smarasderagd, I think) + added more error checking for writing and image to reduce invalid files + separated read and write functions so that they won't both be linked + into a binary when only reading or writing functionality is used + new pngtest image also has interlacing and zTXt + updated documentation to reflect new API + +version 0.90 [January, 1997] + made CRC errors/warnings on critical and ancillary chunks configurable + libpng will use the zlib CRC routines by (compile-time) default + changed DOS small/medium model memory support - needs zlib 1.04 (Tim Wegner) + added external C++ wrapper statements to png.h (Gilles Dauphin) + allow PNG file to be read when some or all of file signature has already + been read from the beginning of the stream. ****This affects the size + of info_struct and invalidates all programs that use a shared libpng**** + fixed png_filler() declarations + fixed? background color conversions + fixed order of error function pointers to match documentation + current chunk name is now available in png_struct to reduce the number + of nearly identical error messages (will simplify multi-lingual + support when available) + try to get ready for unknown-chunk callback functions: + - previously read critical chunks are flagged, so the chunk handling + routines can determine if the chunk is in the right place + - all chunk handling routines have the same prototypes, so we will + be able to handle all chunks via a callback mechanism + try to fix Linux "setjmp" buffer size problems + removed png_large_malloc, png_large_free, and png_realloc functions. + +version 0.95 [March, 1997] + fixed bug in pngwutil.c allocating "up_row" twice and "avg_row" never + fixed bug in PNG file signature compares when start != 0 + changed parameter type of png_set_filler(...filler...) from png_byte + to png_uint_32 + added test for MACOS to ensure that both math.h and fp.h are not #included + added macros for libpng to be compiled as a Windows DLL (Andreas Kupries) + added "packswap" transformation, which changes the endianness of + packed-pixel bytes (Kevin Bracey) + added "strip_alpha" transformation, which removes the alpha channel of + input images without using it (not necessarily a good idea) + added "swap_alpha" transformation, which puts the alpha channel in front + of the color bytes instead of after + removed all implicit variable tests which assume NULL == 0 (I think) + changed several variables to "png_size_t" to show 16/32-bit limitations + added new pCAL chunk read/write support + added experimental filter selection weighting (Greg Roelofs) + removed old png_set_rgbx() and png_set_xrgb() functions that have been + obsolete for about 2 years now (use png_set_filler() instead) + added macros to read 16- and 32-bit ints directly from buffer, to be + used only on those systems that support it (namely PowerPC and 680x0) + With some testing, this may become the default for MACOS/PPC systems. + only calculate CRC on data if we are going to use it + added macros for zTXt compression type PNG_zTXt_COMPRESSION_??? + added macros for simple libpng debugging output selectable at compile time + removed PNG_READ_END_MODE in progressive reader (Smarasderagd) + more description of info_struct in libpng.txt and png.h + more instructions in example.c + more chunk types tested in pngtest.c + renamed pngrcb.c to pngset.c, and all png_read_ functions to be + png_set_. We now have corresponding png_get_ + functions in pngget.c to get information in info_ptr. This isolates + the application from the internal organization of png_info_struct + (good for shared library implementations). + +version 0.96 [May, 1997] + fixed serious bug with < 8bpp images introduced in 0.95 + fixed 256-color transparency bug (Greg Roelofs) + fixed up documentation (Greg Roelofs, Laszlo Nyul) + fixed "error" in pngconf.h for Linux setjmp() behaviour + fixed DOS medium model support (Tim Wegner) + fixed png_check_keyword() for case with error in static string text + added read of CRC after IEND chunk for embedded PNGs (Laszlo Nyul) + added typecasts to quiet compiler errors + added more debugging info + +version 0.97 [January, 1998] + removed PNG_USE_OWN_CRC capability + relocated png_set_crc_action from pngrutil.c to pngrtran.c + fixed typecasts of "new_key", etc. (Andreas Dilger) + added RFC 1152 [sic] date support + fixed bug in gamma handling of 4-bit grayscale + added 2-bit grayscale gamma handling (Glenn R-P) + added more typecasts. 65536L becomes (png_uint_32)65536L, etc. (Glenn R-P) + minor corrections in libpng.txt + added simple sRGB support (Glenn R-P) + easier conditional compiling, e.g. define PNG_READ/WRITE_NOT_FULLY_SUPPORTED; + all configurable options can be selected from command-line instead + of having to edit pngconf.h (Glenn R-P) + fixed memory leak in pngwrite.c (free info_ptr->text) (Glenn R-P) + added more conditions for png_do_background, to avoid changing + black pixels to background when a background is supplied and + no pixels are transparent + repaired PNG_NO_STDIO behaviour + tested NODIV support and made it default behaviour (Greg Roelofs) + added "-m" option and PNGTEST_DEBUG_MEMORY to pngtest (John Bowler) + regularized version numbering scheme and bumped shared-library major + version number to 2 to avoid problems with libpng 0.89 apps (Greg Roelofs) + +version 0.98 [January, 1998] + cleaned up some typos in libpng.txt and in code documentation + fixed memory leaks in pCAL chunk processing (Glenn R-P and John Bowler) + cosmetic change "display_gamma" to "screen_gamma" in pngrtran.c + changed recommendation about file_gamma for PC images to .51 from .45, + in example.c and libpng.txt, added comments to distinguish between + screen_gamma, viewing_gamma, and display_gamma. + changed all references to RFC1152 to read RFC1123 and changed the + PNG_TIME_RFC1152_SUPPORTED macro to PNG_TIME_RFC1123_SUPPORTED + added png_invert_alpha capability (Glenn R-P -- suggestion by Jon Vincent) + changed srgb_intent from png_byte to int to avoid compiler bugs + +version 0.99 [January 30, 1998] + free info_ptr->text instead of end_info_ptr->text in pngread.c (John Bowler) + fixed a longstanding "packswap" bug in pngtrans.c + fixed some inconsistencies in pngconf.h that prevented compiling with + PNG_READ_GAMMA_SUPPORTED and PNG_READ_hIST_SUPPORTED undefined + fixed some typos and made other minor rearrangement of libpng.txt (Andreas) + changed recommendation about file_gamma for PC images to .50 from .51 in + example.c and libpng.txt, and changed file_gamma for sRGB images to .45 + added a number of functions to access information from the png structure + png_get_image_height(), etc. (Glenn R-P, suggestion by Brad Pettit) + added TARGET_MACOS similar to zlib-1.0.8 + define PNG_ALWAYS_EXTERN when __MWERKS__ && WIN32 are defined + added type casting to all png_malloc() function calls +version 0.99a [January 31, 1998] + Added type casts and parentheses to all returns that return a value.(Tim W.) +version 0.99b [February 4, 1998] + Added type cast png_uint_32 on malloc function calls where needed. + Changed type of num_hist from png_uint_32 to int (same as num_palette). + Added checks for rowbytes overflow, in case png_size_t is less than 32 bits. + Renamed makefile.elf to makefile.lnx. +version 0.99c [February 7, 1998] + More type casting. Removed erroneous overflow test in pngmem.c. + Added png_buffered_memcpy() and png_buffered_memset(), apply them to rowbytes. + Added UNIX manual pages libpng.3 (incorporating libpng.txt) and png.5. +version 0.99d [February 11, 1998] + Renamed "far_to_near()" "png_far_to_near()" + Revised libpng.3 + Version 99c "buffered" operations didn't work as intended. Replaced them + with png_memcpy_check() and png_memset_check(). + Added many "if (png_ptr == NULL) return" to quell compiler warnings about + unused png_ptr, mostly in pngget.c and pngset.c. + Check for overlength tRNS chunk present when indexed-color PLTE is read. + Cleaned up spelling errors in libpng.3/libpng.txt + Corrected a problem with png_get_tRNS() which returned undefined trans array +version 0.99e [February 28, 1998] + Corrected png_get_tRNS() again. + Add parentheses for easier reading of pngget.c, fixed "||" should be "&&". + Touched up example.c to make more of it compileable, although the entire + file still can't be compiled (Willem van Schaik) + Fixed a bug in png_do_shift() (Bryan Tsai) + Added a space in png.h prototype for png_write_chunk_start() + Replaced pngtest.png with one created with zlib 1.1.1 + Changed pngtest to report PASS even when file size is different (Jean-loup G.) + Corrected some logic errors in png_do_invert_alpha() (Chris Patterson) +version 0.99f [March 5, 1998] + Corrected a bug in pngpread() introduced in version 99c (Kevin Bracey) + Moved makefiles into a "scripts" directory, and added INSTALL instruction file + Added makefile.os2 and pngos2.def (A. Zabolotny) and makefile.s2x (W. Sebok) + Added pointers to "note on libpng versions" in makefile.lnx and README + Added row callback feature when reading and writing nonprogressive rows + and added a test of this feature in pngtest.c + Added user transform callbacks, with test of the feature in pngtest.c +version 0.99g [March 6, 1998, morning] + Minor changes to pngtest.c to suppress compiler warnings. + Removed "beta" language from documentation. +version 0.99h [March 6, 1998, evening] + Minor changes to previous minor changes to pngtest.c + Changed PNG_READ_NOT_FULLY_SUPPORTED to PNG_READ_TRANSFORMS_NOT_SUPPORTED + and added PNG_PROGRESSIVE_READ_NOT_SUPPORTED macro + Added user transform capability + +version 1.00 [March 7, 1998] + Changed several typedefs in pngrutil.c + Added makefile.wat (Pawel Mrochen), updated makefile.tc3 (Willem van Schaik) + replaced "while(1)" with "for(;;)" + added PNGARG() to prototypes in pngtest.c and removed some prototypes + updated some of the makefiles (Tom Lane) + changed some typedefs (s_start, etc.) in pngrutil.c + fixed dimensions of "short_months" array in pngwrite.c + Replaced ansi2knr.c with the one from jpeg-v6 + +version 1.0.0 [March 8, 1998] + Changed name from 1.00 to 1.0.0 (Adam Costello) + Added smakefile.ppc (with SCOPTIONS.ppc) for Amiga PPC (Andreas Kleinert) +version 1.0.0a [March 9, 1998] + Fixed three bugs in pngrtran.c to make gamma+background handling consistent + (Greg Roelofs) + Changed format of the PNG_LIBPNG_VER integer to xyyzz instead of xyz + for major, minor, and bugfix releases. This is 10001. (Adam Costello, + Tom Lane) + Make months range from 1-12 in png_convert_to_rfc1123 +version 1.0.0b [March 13, 1998] + Quieted compiler complaints about two empty "for" loops in pngrutil.c + Minor changes to makefile.s2x + Removed #ifdef/#endif around a png_free() in pngread.c + +version 1.0.1 [March 14, 1998] + Changed makefile.s2x to reduce security risk of using a relative pathname + Fixed some typos in the documentation (Greg). + Fixed a problem with value of "channels" returned by png_read_update_info() +version 1.0.1a [April 21, 1998] + Optimized Paeth calculations by replacing abs() function calls with intrinsics + plus other loop optimizations. Improves avg decoding speed by about 20%. + Commented out i386istic "align" compiler flags in makefile.lnx. + Reduced the default warning level in some makefiles, to make them consistent. + Removed references to IJG and JPEG in the ansi2knr.c copyright statement. + Fixed a bug in png_do_strip_filler with XXRRGGBB => RRGGBB transformation. + Added grayscale and 16-bit capability to png_do_read_filler(). + Fixed a bug in pngset.c, introduced in version 0.99c, that sets rowbytes + too large when writing an image with bit_depth < 8 (Bob Dellaca). + Corrected some bugs in the experimental weighted filtering heuristics. + Moved a misplaced pngrutil code block that truncates tRNS if it has more + than num_palette entries -- test was done before num_palette was defined. + Fixed a png_convert_to_rfc1123() bug that converts day 31 to 0 (Steve Eddins). + Changed compiler flags in makefile.wat for better optimization (Pawel Mrochen). +version 1.0.1b [May 2, 1998] + Relocated png_do_gray_to_rgb() within png_do_read_transformations() (Greg). + Relocated the png_composite macros from pngrtran.c to png.h (Greg). + Added makefile.sco (contributed by Mike Hopkirk). + Fixed two bugs (missing definitions of "istop") introduced in libpng-1.0.1a. + Fixed a bug in pngrtran.c that would set channels=5 under some circumstances. + More work on the Paeth-filtering, achieving imperceptible speedup (A Kleinert). + More work on loop optimization which may help when compiled with C++ compilers. + Added warnings when people try to use transforms they've defined out. + Collapsed 4 "i" and "c" loops into single "i" loops in pngrtran and pngwtran. + Revised paragraph about png_set_expand() in libpng.txt and libpng.3 (Greg) +version 1.0.1c [May 11, 1998] + Fixed a bug in pngrtran.c (introduced in libpng-1.0.1a) where the masks for + filler bytes should have been 0xff instead of 0xf. + Added max_pixel_depth=32 in pngrutil.c when using FILLER with palette images. + Moved PNG_WRITE_WEIGHTED_FILTER_SUPPORTED and PNG_WRITE_FLUSH_SUPPORTED + out of the PNG_WRITE_TRANSFORMS_NOT_SUPPORTED block of pngconf.h + Added "PNG_NO_WRITE_TRANSFORMS" etc., as alternatives for *_NOT_SUPPORTED, + for consistency, in pngconf.h + Added individual "ifndef PNG_NO_[CAPABILITY]" in pngconf.h to make it easier + to remove unwanted capabilities via the compile line + Made some corrections to grammar (which, it's) in documentation (Greg). + Corrected example.c, use of row_pointers in png_write_image(). +version 1.0.1d [May 24, 1998] + Corrected several statements that used side effects illegally in pngrutil.c + and pngtrans.c, that were introduced in version 1.0.1b + Revised png_read_rows() to avoid repeated if-testing for NULL (A Kleinert) + More corrections to example.c, use of row_pointers in png_write_image() + and png_read_rows(). + Added pngdll.mak and pngdef.pas to scripts directory, contributed by + Bob Dellaca, to make a png32bd.dll with Borland C++ 4.5 + Fixed error in example.c with png_set_text: num_text is 3, not 2 (Guido V.) + Changed several loops from count-down to count-up, for consistency. +version 1.0.1e [June 6, 1998] + Revised libpng.txt and libpng.3 description of png_set_read|write_fn(), and + added warnings when people try to set png_read_fn and png_write_fn in + the same structure. + Added a test such that png_do_gamma will be done when num_trans==0 + for truecolor images that have defined a background. This corrects an + error that was introduced in libpng-0.90 that can cause gamma processing + to be skipped. + Added tests in png.h to include "trans" and "trans_values" in structures + when PNG_READ_BACKGROUND_SUPPORTED or PNG_READ_EXPAND_SUPPORTED is defined. + Add png_free(png_ptr->time_buffer) in png_destroy_read_struct() + Moved png_convert_to_rfc_1123() from pngwrite.c to png.c + Added capability for user-provided malloc_fn() and free_fn() functions, + and revised pngtest.c to demonstrate their use, replacing the + PNGTEST_DEBUG_MEM feature. + Added makefile.w32, for Microsoft C++ 4.0 and later (Tim Wegner). + +version 1.0.2 [June 14, 1998] + Fixed two bugs in makefile.bor . +version 1.0.2a [December 30, 1998] + Replaced and extended code that was removed from png_set_filler() in 1.0.1a. + Fixed a bug in png_do_filler() that made it fail to write filler bytes in + the left-most pixel of each row (Kevin Bracey). + Changed "static pngcharp tIME_string" to "static char tIME_string[30]" + in pngtest.c (Duncan Simpson). + Fixed a bug in pngtest.c that caused pngtest to try to write a tIME chunk + even when no tIME chunk was present in the source file. + Fixed a problem in pngrutil.c: gray_to_rgb didn't always work with 16-bit. + Fixed a problem in png_read_push_finish_row(), which would not skip some + passes that it should skip, for images that are less than 3 pixels high. + Interchanged the order of calls to png_do_swap() and png_do_shift() + in pngwtran.c (John Cromer). + Added #ifdef PNG_DEBUG/#endif surrounding use of PNG_DEBUG in png.h . + Changed "bad adaptive filter type" from error to warning in pngrutil.c . + Fixed a documentation error about default filtering with 8-bit indexed-color. + Separated the PNG_NO_STDIO macro into PNG_NO_STDIO and PNG_NO_CONSOLE_IO + (L. Peter Deutsch). + Added png_set_rgb_to_gray() and png_get_rgb_to_gray_status() functions. + Added png_get_copyright() and png_get_header_version() functions. + Revised comments on png_set_progressive_read_fn() in libpng.txt and example.c + Added information about debugging in libpng.txt and libpng.3 . + Changed "ln -sf" to "ln -s -f" in makefile.s2x, makefile.lnx, and makefile.sco. + Removed lines after Dynamic Dependencies" in makefile.aco . + Revised makefile.dec to make a shared library (Jeremie Petit). + Removed trailing blanks from all files. +version 1.0.2a [January 6, 1999] + Removed misplaced #endif and #ifdef PNG_NO_EXTERN near the end of png.h + Added "if" tests to silence complaints about unused png_ptr in png.h and png.c + Changed "check_if_png" function in example.c to return true (nonzero) if PNG. + Changed libpng.txt to demonstrate png_sig_cmp() instead of png_check_sig() + which is obsolete. + +version 1.0.3 [January 14, 1999] + Added makefile.hux, for Hewlett Packard HPUX 10.20 and 11.00 (Jim Rice) + Added a statement of Y2K compliance in png.h, libpng.3, and Y2KINFO. +version 1.0.3a [August 12, 1999] + Added check for PNG_READ_INTERLACE_SUPPORTED in pngread.c; issue a warning + if an attempt is made to read an interlaced image when it's not supported. + Added check if png_ptr->trans is defined before freeing it in pngread.c + Modified the Y2K statement to include versions back to version 0.71 + Fixed a bug in the check for valid IHDR bit_depth/color_types in pngrutil.c + Modified makefile.wat (added -zp8 flag, ".symbolic", changed some comments) + Replaced leading blanks with tab characters in makefile.hux + Changed "dworkin.wustl.edu" to "ccrc.wustl.edu" in various documents. + Changed (float)red and (float)green to (double)red, (double)green + in png_set_rgb_to_gray() to avoid "promotion" problems in AIX. + Fixed a bug in pngconf.h that omitted when PNG_DEBUG==0 (K Bracey). + Reformatted libpng.3 and libpngpf.3 with proper fonts (script by J. vanZandt). + Updated documentation to refer to the PNG-1.2 specification. + Removed ansi2knr.c and left pointers to the latest source for ansi2knr.c + in makefile.knr, INSTALL, and README (L. Peter Deutsch) + Fixed bugs in calculation of the length of rowbytes when adding alpha + channels to 16-bit images, in pngrtran.c (Chris Nokleberg) + Added function png_set_user_transform_info() to store user_transform_ptr, + user_depth, and user_channels into the png_struct, and a function + png_get_user_transform_ptr() to retrieve the pointer (Chris Nokleberg) + Added function png_set_empty_plte_permitted() to make libpng useable + in MNG applications. + Corrected the typedef for png_free_ptr in png.h (Jesse Jones). + Correct gamma with srgb is 45455 instead of 45000 in pngrutil.c, to be + consistent with PNG-1.2, and allow variance of 500 before complaining. + Added assembler code contributed by Intel in file pngvcrd.c and modified + makefile.w32 to use it (Nirav Chhatrapati, INTEL Corporation, Gilles Vollant) + Changed "ln -s -f" to "ln -f -s" in the makefiles to make Solaris happy. + Added some aliases for png_set_expand() in pngrtran.c, namely + png_set_expand_PLTE(), png_set_expand_depth(), and png_set_expand_tRNS() + (Greg Roelofs, in "PNG: The Definitive Guide"). + Added makefile.beo for BEOS on X86, contributed by Sander Stok. +version 1.0.3b [August 26, 1999] + Replaced 2147483647L several places with PNG_MAX_UINT macro, defined in png.h + Changed leading blanks to tabs in all makefiles. + Define PNG_USE_PNGVCRD in makefile.w32, to get MMX assembler code. + Made alternate versions of png_set_expand() in pngrtran.c, namely + png_set_gray_1_2_4_to_8, png_set_palette_to_rgb, and png_set_tRNS_to_alpha + (Greg Roelofs, in "PNG: The Definitive Guide"). Deleted the 1.0.3a aliases. + Relocated start of 'extern "C"' block in png.h so it doesn't include pngconf.h + Revised calculation of num_blocks in pngmem.c to avoid a potentially + negative shift distance, whose results are undefined in the C language. + Added a check in pngset.c to prevent writing multiple tIME chunks. + Added a check in pngwrite.c to detect invalid small window_bits sizes. +version 1.0.3d [September 4, 1999] + Fixed type casting of igamma in pngrutil.c + Added new png_expand functions to scripts/pngdef.pas and pngos2.def + Added a demo read_user_transform_fn that examines the row filters in pngtest.c + +version 1.0.4 [September 24, 1999] + Define PNG_ALWAYS_EXTERN in pngconf.h if __STDC__ is defined + Delete #define PNG_INTERNAL and include "png.h" from pngasmrd.h + Made several minor corrections to pngtest.c + Renamed the makefiles with longer but more user friendly extensions. + Copied the PNG copyright and license to a separate LICENSE file. + Revised documentation, png.h, and example.c to remove reference to + "viewing_gamma" which no longer appears in the PNG specification. + Revised pngvcrd.c to use MMX code for interlacing only on the final pass. + Updated pngvcrd.c to use the faster C filter algorithms from libpng-1.0.1a + Split makefile.win32vc into two versions, makefile.vcawin32 (uses MMX + assembler code) and makefile.vcwin32 (doesn't). + Added a CPU timing report to pngtest.c (enabled by defining PNGTEST_TIMING) + Added a copy of pngnow.png to the distribution. +version 1.0.4a [September 25, 1999] + Increase max_pixel_depth in pngrutil.c if a user transform needs it. + Changed several division operations to right-shifts in pngvcrd.c +version 1.0.4b [September 30, 1999] + Added parentheses in line 3732 of pngvcrd.c + Added a comment in makefile.linux warning about buggy -O3 in pgcc 2.95.1 +version 1.0.4c [October 1, 1999] + Added a "png_check_version" function in png.c and pngtest.c that will generate + a helpful compiler error if an old png.h is found in the search path. + Changed type of png_user_transform_depth|channels from int to png_byte. +version 1.0.4d [October 6, 1999] + Changed 0.45 to 0.45455 in png_set_sRGB() + Removed unused PLTE entries from pngnow.png + Re-enabled some parts of pngvcrd.c (png_combine_row) that work properly. +version 1.0.4e [October 10, 1999] + Fixed sign error in pngvcrd.c (Greg Roelofs) + Replaced some instances of memcpy with simple assignments in pngvcrd (GR-P) +version 1.0.4f [October 15, 1999] + Surrounded example.c code with #if 0 .. #endif to prevent people from + inadvertently trying to compile it. + Changed png_get_header_version() from a function to a macro in png.h + Added type casting mostly in pngrtran.c and pngwtran.c + Removed some pointless "ptr = NULL" in pngmem.c + Added a "contrib" directory containing the source code from Greg's book. + +version 1.0.5 [October 15, 1999] + Minor editing of the INSTALL and README files. +version 1.0.5a [October 23, 1999] + Added contrib/pngsuite and contrib/pngminus (Willem van Schaik) + Fixed a typo in the png_set_sRGB() function call in example.c (Jan Nijtmans) + Further optimization and bugfix of pngvcrd.c + Revised pngset.c so that it does not allocate or free memory in the user's + text_ptr structure. Instead, it makes its own copy. + Created separate write_end_info_struct in pngtest.c for a more severe test. + Added code in pngwrite.c to free info_ptr->text[i].key to stop a memory leak. +version 1.0.5b [November 23, 1999] + Moved PNG_FLAG_HAVE_CHUNK_HEADER, PNG_FLAG_BACKGROUND_IS_GRAY and + PNG_FLAG_WROTE_tIME from flags to mode. + Added png_write_info_before_PLTE() function. + Fixed some typecasting in contrib/gregbook/*.c + Updated scripts/makevms.com and added makevms.com to contrib/gregbook + and contrib/pngminus (Martin Zinser) +version 1.0.5c [November 26, 1999] + Moved png_get_header_version from png.h to png.c, to accommodate ansi2knr. + Removed all global arrays (according to PNG_NO_GLOBAL_ARRAYS macro), to + accommodate making DLL's: Moved usr_png_ver from global variable to function + png_get_header_ver() in png.c. Moved png_sig to png_sig_bytes in png.c and + eliminated use of png_sig in pngwutil.c. Moved the various png_CHNK arrays + into pngtypes.h. Eliminated use of global png_pass arrays. Declared the + png_CHNK and png_pass arrays to be "const". Made the global arrays + available to applications (although none are used in libpng itself) when + PNG_NO_GLOBAL_ARRAYS is not defined or when PNG_GLOBAL_ARRAYS is defined. + Removed some extraneous "-I" from contrib/pngminus/makefile.std + Changed the PNG_sRGB_INTENT macros in png.h to be consistent with PNG-1.2. + Change PNG_SRGB_INTENT to PNG_sRGB_INTENT in libpng.txt and libpng.3 +version 1.0.5d [November 29, 1999] + Add type cast (png_const_charp) two places in png.c + Eliminated pngtypes.h; use macros instead to declare PNG_CHNK arrays. + Renamed "PNG_GLOBAL_ARRAYS" to "PNG_USE_GLOBAL_ARRAYS" and made available + to applications a macro "PNG_USE_LOCAL_ARRAYS". + comment out (with #ifdef) all the new declarations when + PNG_USE_GLOBAL_ARRAYS is defined. + Added PNG_EXPORT_VAR macro to accommodate making DLL's. +version 1.0.5e [November 30, 1999] + Added iCCP, iTXt, and sPLT support; added "lang" member to the png_text + structure; refactored the inflate/deflate support to make adding new chunks + with trailing compressed parts easier in the future, and added new functions + png_free_iCCP, png_free_pCAL, png_free_sPLT, png_free_text, png_get_iCCP, + png_get_spalettes, png_set_iCCP, png_set_spalettes (Eric S. Raymond). + NOTE: Applications that write text chunks MUST define png_text->lang + before calling png_set_text(). It must be set to NULL if you want to + write tEXt or zTXt chunks. If you want your application to be able to + run with older versions of libpng, use + + #ifdef PNG_iTXt_SUPPORTED + png_text[i].lang = NULL; + #endif + + Changed png_get_oFFs() and png_set_oFFs() to use signed rather than unsigned + offsets (Eric S. Raymond). + Combined PNG_READ_cHNK_SUPPORTED and PNG_WRITE_cHNK_SUPPORTED macros into + PNG_cHNK_SUPPORTED and combined the three types of PNG_text_SUPPORTED + macros, leaving the separate macros also available. + Removed comments on #endifs at the end of many short, non-nested #if-blocks. +version 1.0.5f [December 6, 1999] + Changed makefile.solaris to issue a warning about potential problems when + the ucb "ld" is in the path ahead of the ccs "ld". + Removed "- [date]" from the "synopsis" line in libpng.3 and libpngpf.3. + Added sCAL chunk support (Eric S. Raymond). +version 1.0.5g [December 7, 1999] + Fixed "png_free_spallettes" typo in png.h + Added code to handle new chunks in pngpread.c + Moved PNG_CHNK string macro definitions outside of PNG_NO_EXTERN block + Added "translated_key" to png_text structure and png_write_iTXt(). + Added code in pngwrite.c to work around a newly discovered zlib bug. +version 1.0.5h [December 10, 1999] + NOTE: regarding the note for version 1.0.5e, the following must also + be included in your code: + png_text[i].translated_key = NULL; + Unknown chunk handling is now supported. + Option to eliminate all floating point support was added. Some new + fixed-point functions such as png_set_gAMA_fixed() were added. + Expanded tabs and removed trailing blanks in source files. +version 1.0.5i [December 13, 1999] + Added some type casts to silence compiler warnings. + Renamed "png_free_spalette" to "png_free_spalettes" for consistency. + Removed leading blanks from a #define in pngvcrd.c + Added some parameters to the new png_set_keep_unknown_chunks() function. + Added a test for up->location != 0 in the first instance of writing + unknown chunks in pngwrite.c + Changed "num" to "i" in png_free_spalettes() and png_free_unknowns() to + prevent recursion. + Added png_free_hIST() function. + Various patches to fix bugs in the sCAL and integer cHRM processing, + and to add some convenience macros for use with sCAL. +version 1.0.5j [December 21, 1999] + Changed "unit" parameter of png_write_sCAL from png_byte to int, to work + around buggy compilers. + Added new type "png_fixed_point" for integers that hold float*100000 values + Restored backward compatibility of tEXt/zTXt chunk processing: + Restored the first four members of png_text to the same order as v.1.0.5d. + Added members "lang_key" and "itxt_length" to png_text struct. Set + text_length=0 when "text" contains iTXt data. Use the "compression" + member to distinguish among tEXt/zTXt/iTXt types. Added + PNG_ITXT_COMPRESSION_NONE (1) and PNG_ITXT_COMPRESSION_zTXt(2) macros. + The "Note" above, about backward incompatibility of libpng-1.0.5e, no + longer applies. + Fixed png_read|write_iTXt() to read|write parameters in the right order, + and to write the iTXt chunk after IDAT if it appears in the end_ptr. + Added pnggccrd.c, version of pngvcrd.c Intel assembler for gcc (Greg Roelofs) + Reversed the order of trying to write floating-point and fixed-point gAMA. +version 1.0.5k [December 27, 1999] + Added many parentheses, e.g., "if (a && b & c)" becomes "if (a && (b & c))" + Added png_handle_as_unknown() function (Glenn) + Added png_free_chunk_list() function and chunk_list and num_chunk_list members + of png_ptr. + Eliminated erroneous warnings about multiple sPLT chunks and sPLT-after-PLTE. + Fixed a libpng-1.0.5h bug in pngrutil.c that was issuing erroneous warnings + about ignoring incorrect gAMA with sRGB (gAMA was in fact not ignored) + Added png_free_tRNS(); png_set_tRNS() now malloc's its own trans array (ESR). + Define png_get_int_32 when oFFs chunk is supported as well as when pCAL is. + Changed type of proflen from png_int_32 to png_uint_32 in png_get_iCCP(). +version 1.0.5l [January 1, 2000] + Added functions png_set_read_user_chunk_fn() and png_get_user_chunk_ptr() + for setting a callback function to handle unknown chunks and for + retrieving the associated user pointer (Glenn). +version 1.0.5m [January 7, 2000] + Added high-level functions png_read_png(), png_write_png(), png_free_pixels(). +version 1.0.5n [January 9, 2000] + Added png_free_PLTE() function, and modified png_set_PLTE() to malloc its + own memory for info_ptr->palette. This makes it safe for the calling + application to free its copy of the palette any time after it calls + png_set_PLTE(). +version 1.0.5o [January 20, 2000] + Cosmetic changes only (removed some trailing blanks and TABs) +version 1.0.5p [January 31, 2000] + Renamed pngdll.mak to makefile.bd32 + Cosmetic changes in pngtest.c +version 1.0.5q [February 5, 2000] + Relocated the makefile.solaris warning about PATH problems. + Fixed pngvcrd.c bug by pushing/popping registers in mmxsupport (Bruce Oberg) + Revised makefile.gcmmx + Added PNG_SETJMP_SUPPORTED, PNG_SETJMP_NOT_SUPPORTED, and PNG_ABORT() macros +version 1.0.5r [February 7, 2000] + Removed superfluous prototype for png_get_itxt from png.h + Fixed a bug in pngrtran.c that improperly expanded the background color. + Return *num_text=0 from png_get_text() when appropriate, and fix documentation + of png_get_text() in libpng.txt/libpng.3. +version 1.0.5s [February 18, 2000] + Added "png_jmp_env()" macro to pngconf.h, to help people migrate to the + new error handler that's planned for the next libpng release, and changed + example.c, pngtest.c, and contrib programs to use this macro. + Revised some of the DLL-export macros in pngconf.h (Greg Roelofs) + Fixed a bug in png_read_png() that caused it to fail to expand some images + that it should have expanded. + Fixed some mistakes in the unused and undocumented INCH_CONVERSIONS functions + in pngget.c + Changed the allocation of palette, history, and trans arrays back to + the version 1.0.5 method (linking instead of copying) which restores + backward compatibility with version 1.0.5. Added some remarks about + that in example.c. Added "free_me" member to info_ptr and png_ptr + and added png_free_data() function. + Updated makefile.linux and makefile.gccmmx to make directories conditionally. + Made cosmetic changes to pngasmrd.h + Added png_set_rows() and png_get_rows(), for use with png_read|write_png(). + Modified png_read_png() to allocate info_ptr->row_pointers only if it + hasn't already been allocated. +version 1.0.5t [March 4, 2000] + Changed png_jmp_env() migration aiding macro to png_jmpbuf(). + Fixed "interlace" typo (should be "interlaced") in contrib/gregbook/read2-x.c + Fixed bug with use of PNG_BEFORE_IHDR bit in png_ptr->mode, introduced when + PNG_FLAG_HAVE_CHUNK_HEADER was moved into png_ptr->mode in version 1.0.5b + Files in contrib/gregbook were revised to use png_jmpbuf() and to select + a 24-bit visual if one is available, and to allow abbreviated options. + Files in contrib/pngminus were revised to use the png_jmpbuf() macro. + Removed spaces in makefile.linux and makefile.gcmmx, introduced in 1.0.5s +version 1.0.5u [March 5, 2000] + Simplified the code that detects old png.h in png.c and pngtest.c + Renamed png_spalette (_p, _pp) to png_sPLT_t (_tp, _tpp) + Increased precision of rgb_to_gray calculations from 8 to 15 bits and + added png_set_rgb_to_gray_fixed() function. + Added makefile.bc32 (32-bit Borland C++, C mode) +version 1.0.5v [March 11, 2000] + Added some parentheses to the png_jmpbuf macro definition. + Updated references to the zlib home page, which has moved to freesoftware.com. + Corrected bugs in documentation regarding png_read_row() and png_write_row(). + Updated documentation of png_rgb_to_gray calculations in libpng.3/libpng.txt. + Renamed makefile.borland,turboc3 back to makefile.bor,tc3 as in version 1.0.3, + revised borland makefiles; added makefile.ibmvac3 and makefile.gcc (Cosmin) + +version 1.0.6 [March 20, 2000] + Minor revisions of makefile.bor, libpng.txt, and gregbook/rpng2-win.c + Added makefile.sggcc (SGI IRIX with gcc) +version 1.0.6d [April 7, 2000] + Changed sprintf() to strcpy() in png_write_sCAL_s() to work without STDIO + Added data_length parameter to png_decompress_chunk() function + Revised documentation to remove reference to abandoned png_free_chnk functions + Fixed an error in png_rgb_to_gray_fixed() + Revised example.c, usage of png_destroy_write_struct(). + Renamed makefile.ibmvac3 to makefile.ibmc, added libpng.icc IBM project file + Added a check for info_ptr->free_me&PNG_FREE_TEXT when freeing text in png.c + Simplify png_sig_bytes() function to remove use of non-ISO-C strdup(). +version 1.0.6e [April 9, 2000] + Added png_data_freer() function. + In the code that checks for over-length tRNS chunks, added check of + info_ptr->num_trans as well as png_ptr->num_trans (Matthias Benckmann) + Minor revisions of libpng.txt/libpng.3. + Check for existing data and free it if the free_me flag is set, in png_set_*() + and png_handle_*(). + Only define PNG_WEIGHTED_FILTERS_SUPPORTED when PNG_FLOATING_POINT_SUPPORTED + is defined. + Changed several instances of PNG_NO_CONSOLE_ID to PNG_NO_STDIO in pngrutil.c + and mentioned the purposes of the two macros in libpng.txt/libpng.3. +version 1.0.6f [April 14, 2000] + Revised png_set_iCCP() and png_set_rows() to avoid prematurely freeing data. + Add checks in png_set_text() for NULL members of the input text structure. + Revised libpng.txt/libpng.3. + Removed superfluous prototype for png_set_itxt from png.h + Removed "else" from pngread.c, after png_error(), and changed "0" to "length". + Changed several png_errors about malformed ancillary chunks to png_warnings. +version 1.0.6g [April 24, 2000] + Added png_pass-* arrays to pnggccrd.c when PNG_USE_LOCAL_ARRAYS is defined. + Relocated paragraph about png_set_background() in libpng.3/libpng.txt + and other revisions (Matthias Benckmann) + Relocated info_ptr->free_me, png_ptr->free_me, and other info_ptr and + png_ptr members to restore binary compatibility with libpng-1.0.5 + (breaks compatibility with libpng-1.0.6). +version 1.0.6h [April 24, 2000] + Changed shared library so-number pattern from 2.x.y.z to xy.z (this builds + libpng.so.10 & libpng.so.10.6h instead of libpng.so.2 & libpng.so.2.1.0.6h) + This is a temporary change for test purposes. +version 1.0.6i [May 2, 2000] + Rearranged some members at the end of png_info and png_struct, to put + unknown_chunks_num and free_me within the original size of the png_structs + and free_me, png_read_user_fn, and png_free_fn within the original png_info, + because some old applications allocate the structs directly instead of + using png_create_*(). + Added documentation of user memory functions in libpng.txt/libpng.3 + Modified png_read_png so that it will use user_allocated row_pointers + if present, unless free_me directs that it be freed, and added description + of the use of png_set_rows() and png_get_rows() in libpng.txt/libpng.3. + Added PNG_LEGACY_SUPPORTED macro, and #ifdef out all new (since version + 1.00) members of png_struct and png_info, to regain binary compatibility + when you define this macro. Capabilities lost in this event + are user transforms (new in version 1.0.0),the user transform pointer + (new in version 1.0.2), rgb_to_gray (new in 1.0.5), iCCP, sCAL, sPLT, + the high-level interface, and unknown chunks support (all new in 1.0.6). + This was necessary because of old applications that allocate the structs + directly as authors were instructed to do in libpng-0.88 and earlier, + instead of using png_create_*(). + Added modes PNG_CREATED_READ_STRUCT and PNG_CREATED_WRITE_STRUCT which + can be used to detect codes that directly allocate the structs, and + code to check these modes in png_read_init() and png_write_init() and + generate a libpng error if the modes aren't set and PNG_LEGACY_SUPPORTED + was not defined. + Added makefile.intel and updated makefile.watcom (Pawel Mrochen) +version 1.0.6j [May 3, 2000] + Overloaded png_read_init() and png_write_init() with macros that convert + calls to png_read_init_2() or png_write_init_2() that check the version + and structure sizes. +version 1.0.7beta11 [May 7, 2000] + Removed the new PNG_CREATED_READ_STRUCT and PNG_CREATED_WRITE_STRUCT modes + which are no longer used. + Eliminated the three new members of png_text when PNG_LEGACY_SUPPORTED is + defined or when neither PNG_READ_iTXt_SUPPORTED nor PNG_WRITE_iTXT_SUPPORTED + is defined. + Made PNG_NO_READ|WRITE_iTXt the default setting, to avoid memory + overrun when old applications fill the info_ptr->text structure directly. + Added PNGAPI macro, and added it to the definitions of all exported functions. + Relocated version macro definitions ahead of the includes of zlib.h and + pngconf.h in png.h. +version 1.0.7beta12 [May 12, 2000] + Revised pngset.c to avoid a problem with expanding the png_debug macro. + Deleted some extraneous defines from pngconf.h + Made PNG_NO_CONSOLE_IO the default condition when PNG_BUILD_DLL is defined. + Use MSC _RPTn debugging instead of fprintf if _MSC_VER is defined. + Added png_access_version_number() function. + Check for mask&PNG_FREE_CHNK (for TEXT, SCAL, PCAL) in png_free_data(). + Expanded libpng.3/libpng.txt information about png_data_freer(). +version 1.0.7beta14 [May 17, 2000] (beta13 was not published) + Changed pnggccrd.c and pngvcrd.c to handle bad adaptive filter types as + warnings instead of errors, as pngrutil.c does. + Set the PNG_INFO_IDAT valid flag in png_set_rows() so png_write_png() + will actually write IDATs. + Made the default PNG_USE_LOCAL_ARRAYS depend on PNG_DLL instead of WIN32. + Make png_free_data() ignore its final parameter except when freeing data + that can have multiple instances (text, sPLT, unknowns). + Fixed a new bug in png_set_rows(). + Removed info_ptr->valid tests from png_free_data(), as in version 1.0.5. + Added png_set_invalid() function. + Fixed incorrect illustrations of png_destroy_write_struct() in example.c. +version 1.0.7beta15 [May 30, 2000] + Revised the deliberately erroneous Linux setjmp code in pngconf.h to produce + fewer error messages. + Rearranged checks for Z_OK to check the most likely path first in pngpread.c + and pngwutil.c. + Added checks in pngtest.c for png_create_*() returning NULL, and mentioned + in libpng.txt/libpng.3 the need for applications to check this. + Changed names of png_default_*() functions in pngtest to pngtest_*(). + Changed return type of png_get_x|y_offset_*() from png_uint_32 to png_int_32. + Fixed some bugs in the unused PNG_INCH_CONVERSIONS functions in pngget.c + Set each pointer to NULL after freeing it in png_free_data(). + Worked around a problem in pngconf.h; AIX's strings.h defines an "index" + macro that conflicts with libpng's png_color_16.index. (Dimitri Papadapoulos) + Added "msvc" directory with MSVC++ project files (Simon-Pierre Cadieux). +version 1.0.7beta16 [June 4, 2000] + Revised the workaround of AIX string.h "index" bug. + Added a check for overlength PLTE chunk in pngrutil.c. + Added PNG_NO_POINTER_INDEXING macro to use array-indexing instead of pointer + indexing in pngrutil.c and pngwutil.c to accommodate a buggy compiler. + Added a warning in png_decompress_chunk() when it runs out of data, e.g. + when it tries to read an erroneous PhotoShop iCCP chunk. + Added PNG_USE_DLL macro. + Revised the copyright/disclaimer/license notice. + Added contrib/msvctest directory +version 1.0.7rc1 [June 9, 2000] + Corrected the definition of PNG_TRANSFORM_INVERT_ALPHA (0x0400 not 0x0200) + Added contrib/visupng directory (Willem van Schaik) +version 1.0.7beta18 [June 23, 2000] + Revised PNGAPI definition, and pngvcrd.c to work with __GCC__ + and do not redefine PNGAPI if it is passed in via a compiler directive. + Revised visupng/PngFile.c to remove returns from within the Try block. + Removed leading underscores from "_PNG_H" and "_PNG_SAVE_BSD_SOURCE" macros. + Updated contrib/visupng/cexcept.h to version 1.0.0. + Fixed bugs in pngwrite.c and pngwutil.c that prevented writing iCCP chunks. +version 1.0.7rc2 [June 28, 2000] + Updated license to include disclaimers required by UCITA. + Fixed "DJBPP" typo in pnggccrd.c introduced in beta18. + +version 1.0.7 [July 1, 2000] + Revised the definition of "trans_values" in libpng.3/libpng.txt +version 1.0.8beta1 [July 8, 2000] + Added png_free(png_ptr, key) two places in pngpread.c to stop memory leaks. + Changed PNG_NO_STDIO to PNG_NO_CONSOLE_IO, several places in pngrutil.c and + pngwutil.c. + Changed PNG_EXPORT_VAR to use PNG_IMPEXP, in pngconf.h. + Removed unused "#include " from png.c + Added WindowsCE support. + Revised pnggccrd.c to work with gcc-2.95.2 and in the Cygwin environment. +version 1.0.8beta2 [July 10, 2000] + Added project files to the wince directory and made further revisions + of pngtest.c, pngrio.c, and pngwio.c in support of WindowsCE. +version 1.0.8beta3 [July 11, 2000] + Only set the PNG_FLAG_FREE_TRNS or PNG_FREE_TRNS flag in png_handle_tRNS() + for indexed-color input files to avoid potential double-freeing trans array + under some unusual conditions; problem was introduced in version 1.0.6f. + Further revisions to pngtest.c and files in the wince subdirectory. +version 1.0.8beta4 [July 14, 2000] + Added the files pngbar.png and pngbar.jpg to the distribution. + Added makefile.cygwin, and cygwin support in pngconf.h + Added PNG_NO_ZALLOC_ZERO macro (makes png_zalloc skip zeroing memory) +version 1.0.8rc1 [July 16, 2000] + Revised png_debug() macros and statements to eliminate compiler warnings. + +version 1.0.8 [July 24, 2000] + Added png_flush() in pngwrite.c, after png_write_IEND(). + Updated makefile.hpux to build a shared library. +version 1.0.9beta1 [November 10, 2000] + Fixed typo in scripts/makefile.hpux + Updated makevms.com in scripts and contrib/* and contrib/* (Martin Zinser) + Fixed seqence-point bug in contrib/pngminus/png2pnm (Martin Zinser) + Changed "cdrom.com" in documentation to "libpng.org" + Revised pnggccrd.c to get it all working, and updated makefile.gcmmx (Greg). + Changed type of "params" from voidp to png_voidp in png_read|write_png(). + Make sure PNGAPI and PNG_IMPEXP are defined in pngconf.h. + Revised the 3 instances of WRITEFILE in pngtest.c. + Relocated "msvc" and "wince" project subdirectories into "dll" subdirectory. + Updated png.rc in dll/msvc project + Revised makefile.dec to define and use LIBPATH and INCPATH + Increased size of global png_libpng_ver[] array from 12 to 18 chars. + Made global png_libpng_ver[], png_sig[] and png_pass_*[] arrays const. + Removed duplicate png_crc_finish() from png_handle_bKGD() function. + Added a warning when application calls png_read_update_info() multiple times. + Revised makefile.cygwin + Fixed bugs in iCCP support in pngrutil.c and pngwutil.c. + Replaced png_set_empty_plte_permitted() with png_permit_mng_features(). +version 1.0.9beta2 [November 19, 2000] + Renamed the "dll" subdirectory "projects". + Added borland project files to "projects" subdirectory. + Set VS_FF_PRERELEASE and VS_FF_PATCHED flags in msvc/png.rc when appropriate. + Add error message in png_set_compression_buffer_size() when malloc fails. +version 1.0.9beta3 [November 23, 2000] + Revised PNG_LIBPNG_BUILD_TYPE macro in png.h, used in the msvc project. + Removed the png_flush() in pngwrite.c that crashes some applications + that don't set png_output_flush_fn. + Added makefile.macosx and makefile.aix to scripts directory. +version 1.0.9beta4 [December 1, 2000] + Change png_chunk_warning to png_warning in png_check_keyword(). + Increased the first part of msg buffer from 16 to 18 in png_chunk_error(). +version 1.0.9beta5 [December 15, 2000] + Added support for filter method 64 (for PNG datastreams embedded in MNG). +version 1.0.9beta6 [December 18, 2000] + Revised png_set_filter() to accept filter method 64 when appropriate. + Added new PNG_HAVE_PNG_SIGNATURE bit to png_ptr->mode and use it to + help prevent applications from using MNG features in PNG datastreams. + Added png_permit_mng_features() function. + Revised libpng.3/libpng.txt. Changed "filter type" to "filter method". +version 1.0.9rc1 [December 23, 2000] + Revised test for PNG_HAVE_PNG_SIGNATURE in pngrutil.c + Fixed error handling of unknown compression type in png_decompress_chunk(). + In pngconf.h, define __cdecl when _MSC_VER is defined. +version 1.0.9beta7 [December 28, 2000] + Changed PNG_TEXT_COMPRESSION_zTXt to PNG_COMPRESSION_TYPE_BASE several places. + Revised memory management in png_set_hIST and png_handle_hIST in a backward + compatible manner. PLTE and tRNS were revised similarly. + Revised the iCCP chunk reader to ignore trailing garbage. +version 1.0.9beta8 [January 12, 2001] + Moved pngasmrd.h into pngconf.h. + Improved handling of out-of-spec garbage iCCP chunks generated by PhotoShop. +version 1.0.9beta9 [January 15, 2001] + Added png_set_invalid, png_permit_mng_features, and png_mmx_supported to + wince and msvc project module definition files. + Minor revision of makefile.cygwin. + Fixed bug with progressive reading of narrow interlaced images in pngpread.c +version 1.0.9beta10 [January 16, 2001] + Do not typedef png_FILE_p in pngconf.h when PNG_NO_STDIO is defined. + Fixed "png_mmx_supported" typo in project definition files. +version 1.0.9beta11 [January 19, 2001] + Updated makefile.sgi to make shared library. + Removed png_mmx_support() function and disabled PNG_MNG_FEATURES_SUPPORTED + by default, for the benefit of DLL forward compatibility. These will + be re-enabled in version 1.2.0. +version 1.0.9rc2 [January 22, 2001] + Revised cygwin support. + +version 1.0.9 [January 31, 2001] + Added check of cygwin's ALL_STATIC in pngconf.h + Added "-nommx" parameter to contrib/gregbook/rpng2-win and rpng2-x demos. +version 1.0.10beta1 [March 14, 2001] + Revised makefile.dec, makefile.sgi, and makefile.sggcc; added makefile.hpgcc. + Reformatted libpng.3 to eliminate bad line breaks. + Added checks for _mmx_supported in the read_filter_row function of pnggccrd.c + Added prototype for png_mmx_support() near the top of pnggccrd.c + Moved some error checking from png_handle_IHDR to png_set_IHDR. + Added PNG_NO_READ_SUPPORTED and PNG_NO_WRITE_SUPPORTED macros. + Revised png_mmx_support() function in pnggccrd.c + Restored version 1.0.8 PNG_WRITE_EMPTY_PLTE_SUPPORTED behavior in pngwutil.c + Fixed memory leak in contrib/visupng/PngFile.c + Fixed bugs in png_combine_row() in pnggccrd.c and pngvcrd.c (C version) + Added warnings when retrieving or setting gamma=0. + Increased the first part of msg buffer from 16 to 18 in png_chunk_warning(). +version 1.0.10rc1 [March 23, 2001] + Changed all instances of memcpy, strcpy, and strlen to png_memcpy, png_strcpy, + and png_strlen. + Revised png_mmx_supported() function in pnggccrd.c to return proper value. + Fixed bug in progressive reading (pngpread.c) with small images (height < 8). + +version 1.0.10 [March 30, 2001] + Deleted extraneous space (introduced in 1.0.9) from line 42 of makefile.cygwin + Added beos project files (Chris Herborth) +version 1.0.11beta1 [April 3, 2001] + Added type casts on several png_malloc() calls (Dimitri Papadapoulos). + Removed a no-longer needed AIX work-around from pngconf.h + Changed several "//" single-line comments to C-style in pnggccrd.c +version 1.0.11beta2 [April 11, 2001] + Removed PNGAPI from several functions whose prototypes did not have PNGAPI. + Updated scripts/pngos2.def +version 1.0.11beta3 [April 14, 2001] + Added checking the results of many instances of png_malloc() for NULL +version 1.0.11beta4 [April 20, 2001] + Undid the changes from version 1.0.11beta3. Added a check for NULL return + from user's malloc_fn(). + Removed some useless type casts of the NULL pointer. + Added makefile.netbsd + +version 1.0.11 [April 27, 2001] + Revised makefile.netbsd +version 1.0.12beta1 [May 14, 2001] + Test for Windows platform in pngconf.h when including malloc.h (Emmanuel Blot) + Updated makefile.cygwin and handling of Cygwin's ALL_STATIC in pngconf.h + Added some never-to-be-executed code in pnggccrd.c to quiet compiler warnings. + Eliminated the png_error about apps using png_read|write_init(). Instead, + libpng will reallocate the png_struct and info_struct if they are too small. + This retains future binary compatibility for old applications written for + libpng-0.88 and earlier. +version 1.2.0beta1 [May 6, 2001] + Bumped DLLNUM to 2. + Re-enabled PNG_MNG_FEATURES_SUPPORTED and enabled PNG_ASSEMBLER_CODE_SUPPORTED + by default. + Added runtime selection of MMX features. + Added png_set_strip_error_numbers function and related macros. +version 1.2.0beta2 [May 7, 2001] + Finished merging 1.2.0beta1 with version 1.0.11 + Added a check for attempts to read or write PLTE in grayscale PNG datastreams. +version 1.2.0beta3 [May 17, 2001] + Enabled user memory function by default. + Modified png_create_struct so it passes user mem_ptr to user memory allocator. + Increased png_mng_features flag from png_byte to png_uint_32. + Bumped shared-library (so-number) and dll-number to 3. +version 1.2.0beta4 [June 23, 2001] + Check for missing profile length field in iCCP chunk and free chunk_data + in case of truncated iCCP chunk. + Bumped shared-library number to 3 in makefile.sgi and makefile.sggcc + Bumped dll-number from 2 to 3 in makefile.cygwin + Revised contrib/gregbook/rpng*-x.c to avoid a memory leak and to exit cleanly + if user attempts to run it on an 8-bit display. + Updated contrib/gregbook + Use png_malloc instead of png_zalloc to allocate palette in pngset.c + Updated makefile.ibmc + Added some typecasts to eliminate gcc 3.0 warnings. Changed prototypes + of png_write_oFFS width and height from png_uint_32 to png_int_32. + Updated example.c + Revised prototypes for png_debug_malloc and png_debug_free in pngtest.c +version 1.2.0beta5 [August 8, 2001] + Revised contrib/gregbook + Revised makefile.gcmmx + Revised pnggccrd.c to conditionally compile some thread-unsafe code only + when PNG_THREAD_UNSAFE_OK is defined. + Added tests to prevent pngwutil.c from writing a bKGD or tRNS chunk with + value exceeding 2^bit_depth-1 + Revised makefile.sgi and makefile.sggcc + Replaced calls to fprintf(stderr,...) with png_warning() in pnggccrd.c + Removed restriction that do_invert_mono only operate on 1-bit opaque files + +version 1.2.0 [September 1, 2001] + Changed a png_warning() to png_debug() in pnggccrd.c + Fixed contrib/gregbook/rpng-x.c, rpng2-x.c to avoid crash with XFreeGC(). +version 1.2.1beta1 [October 19, 2001] + Revised makefile.std in contrib/pngminus + Include background_1 in png_struct regardless of gamma support. + Revised makefile.netbsd and makefile.macosx, added makefile.darwin. + Revised example.c to provide more details about using row_callback(). +version 1.2.1beta2 [October 25, 2001] + Added type cast to each NULL appearing in a function call, except for + WINCE functions. + Added makefile.so9. +version 1.2.1beta3 [October 27, 2001] + Removed type casts from all NULLs. + Simplified png_create_struct_2(). +version 1.2.1beta4 [November 7, 2001] + Revised png_create_info_struct() and png_creat_struct_2(). + Added error message if png_write_info() was omitted. + Type cast NULLs appearing in function calls when _NO_PROTO or + PNG_TYPECAST_NULL is defined. +version 1.2.1rc1 [November 24, 2001] + Type cast NULLs appearing in function calls except when PNG_NO_TYPECAST_NULL + is defined. + Changed typecast of "size" argument to png_size_t in pngmem.c calls to + the user malloc_fn, to agree with the prototype in png.h + Added a pop/push operation to pnggccrd.c, to preserve Eflag (Maxim Sobolev) + Updated makefile.sgi to recognize LIBPATH and INCPATH. + Updated various makefiles so "make clean" does not remove previous major + version of the shared library. +version 1.2.1rc2 [December 4, 2001] + Always allocate 256-entry internal palette, hist, and trans arrays, to + avoid out-of-bounds memory reference caused by invalid PNG datastreams. + Added a check for prefix_length > data_length in iCCP chunk handler. + +version 1.2.1 [December 7, 2001] + None. +version 1.2.2beta1 [February 22, 2002] + Fixed a bug with reading the length of iCCP profiles (Larry Reeves). + Revised makefile.linux, makefile.gcmmx, and makefile.sgi to generate + libpng.a, libpng12.so (not libpng.so.3), and libpng12/png.h + Revised makefile.darwin to remove "-undefined suppress" option. + Added checks for gamma and chromaticity values over 21474.83, which exceed + the limit for PNG unsigned 32-bit integers when encoded. + Revised calls to png_create_read_struct() and png_create_write_struct() + for simpler debugging. + Revised png_zalloc() so zlib handles errors (uses PNG_FLAG_MALLOC_NULL_MEM_OK) +version 1.2.2beta2 [February 23, 2002] + Check chunk_length and idat_size for invalid (over PNG_MAX_UINT) lengths. + Check for invalid image dimensions in png_get_IHDR. + Added missing "fi;" in the install target of the SGI makefiles. + Added install-static to all makefiles that make shared libraries. + Always do gamma compensation when image is partially transparent. +version 1.2.2beta3 [March 7, 2002] + Compute background.gray and background_1.gray even when color_type is RGB + in case image gets reduced to gray later. + Modified shared-library makefiles to install pkgconfig/libpngNN.pc. + Export (with PNGAPI) png_zalloc, png_zfree, and png_handle_as_unknown + Removed unused png_write_destroy_info prototype from png.h + Eliminated incorrect use of width_mmx from pnggccrd.c in pixel_bytes == 8 case + Added install-shared target to all makefiles that make shared libraries. + Stopped a double free of palette, hist, and trans when not using free_me. + Added makefile.32sunu for Sun Ultra 32 and makefile.64sunu for Sun Ultra 64. +version 1.2.2beta4 [March 8, 2002] + Compute background.gray and background_1.gray even when color_type is RGB + in case image gets reduced to gray later (Jason Summers). + Relocated a misplaced /bin/rm in the "install-shared" makefile targets + Added PNG_1_0_X macro which can be used to build a 1.0.x-compatible library. +version 1.2.2beta5 [March 26, 2002] + Added missing PNGAPI to several function definitions. + Check for invalid bit_depth or color_type in png_get_IHDR(), and + check for missing PLTE or IHDR in png_push_read_chunk() (Matthias Clasen). + Revised iTXt support to accept NULL for lang and lang_key. + Compute gamma for color components of background even when color_type is gray. + Changed "()" to "{}" in scripts/libpng.pc.in. + Revised makefiles to put png.h and pngconf.h only in $prefix/include/libpngNN + Revised makefiles to make symlink to libpng.so.NN in addition to libpngNN.so +version 1.2.2beta6 [March 31, 2002] +version 1.0.13beta1 [March 31, 2002] + Prevent png_zalloc() from trying to memset memory that it failed to acquire. + Add typecasts of PNG_MAX_UINT in pngset_cHRM_fixed() (Matt Holgate). + Ensure that the right function (user or default) is used to free the + png_struct after an error in png_create_read_struct_2(). +version 1.2.2rc1 [April 7, 2002] +version 1.0.13rc1 [April 7, 2002] + Save the ebx register in pnggccrd.c (Sami Farin) + Add "mem_ptr = png_ptr->mem_ptr" in png_destroy_write_struct() (Paul Gardner). + Updated makefiles to put headers in include/libpng and remove old include/*.h. + +version 1.2.2 [April 15, 2002] +version 1.0.13 [April 15, 2002] + Revised description of png_set_filter() in libpng.3/libpng.txt. + Revised makefile.netbsd and added makefile.neNNbsd and makefile.freebsd +version 1.0.13patch01 [April 17, 2002] +version 1.2.2patch01 [April 17, 2002] + Changed ${PNGMAJ}.${PNGVER} bug to ${PNGVER} in makefile.sgi and makefile.sggcc + Fixed VER -> PNGVER typo in makefile.macosx and added install-static to install + Added install: target to makefile.32sunu and makefile.64sunu +version 1.0.13patch03 [April 18, 2002] +version 1.2.2patch03 [April 18, 2002] + Revised 15 makefiles to link libpng.a to libpngNN.a and the include libpng + subdirectory to libpngNN subdirectory without the full pathname. + Moved generation of libpng.pc from "install" to "all" in 15 makefiles. +version 1.2.3rc1 [April 28, 2002] + Added install-man target to 15 makefiles (Dimitri Papadopolous-Orfanos). + Added $(DESTDIR) feature to 24 makefiles (Tim Mooney) + Fixed bug with $prefix, should be $(prefix) in makefile.hpux. + Updated cygwin-specific portion of pngconf.h and revised makefile.cygwin + Added a link from libpngNN.pc to libpng.pc in 15 makefiles. + Added links from include/libpngNN/*.h to include/*.h in 24 makefiles. + Revised makefile.darwin to make relative links without full pathname. + Added setjmp() at the end of png_create_*_struct_2() in case user forgets + to put one in their application. + Restored png_zalloc() and png_zfree() prototypes to version 1.2.1 and + removed them from module definition files. +version 1.2.3rc2 [May 1, 2002] + Fixed bug in reporting number of channels in pngget.c and pngset.c, + that was introduced in version 1.2.2beta5. + Exported png_zalloc(), png_zfree(), png_default_read(), png_default_write(), + png_default_flush(), and png_push_fill_buffer() and included them in + module definition files. + Added "libpng.pc" dependency to the "install-shared" target in 15 makefiles. +version 1.2.3rc3 [May 1, 2002] + Revised prototype for png_default_flush() + Remove old libpng.pc and libpngNN.pc before installing new ones. +version 1.2.3rc4 [May 2, 2002] + Typos in *.def files (png_default_read|write -> png_default_read|write_data) + In makefiles, changed rm libpng.NN.pc to rm libpngNN.pc + Added libpng-config and libpngNN-config and modified makefiles to install them. + Changed $(MANPATH) to $(DESTDIR)$(MANPATH) in makefiles + Added "Win32 DLL VB" configuration to projects/msvc/libpng.dsp +version 1.2.3rc5 [May 11, 2002] + Changed "error" and "message" in prototypes to "error_message" and + "warning_message" to avoid namespace conflict. + Revised 15 makefiles to build libpng-config from libpng-config-*.in + Once more restored png_zalloc and png_zfree to regular nonexported form. + Restored png_default_read|write_data, png_default_flush, png_read_fill_buffer + to nonexported form, but with PNGAPI, and removed them from module def files. +version 1.2.3rc6 [May 14, 2002] + Removed "PNGAPI" from png_zalloc() and png_zfree() in png.c + Changed "Gz" to "Gd" in projects/msvc/libpng.dsp and zlib.dsp. + Removed leftover libpng-config "sed" script from four makefiles. + Revised libpng-config creating script in 16 makefiles. + +version 1.2.3 [May 22, 2002] + Revised libpng-config target in makefile.cygwin. + Removed description of png_set_mem_fn() from documentation. + Revised makefile.freebsd. + Minor cosmetic changes to 15 makefiles, e.g., $(DI) = $(DESTDIR)/$(INCDIR). + Revised projects/msvc/README.txt + Changed -lpng to -lpngNN in LDFLAGS in several makefiles. +version 1.2.4beta1 [May 24, 2002] + Added libpng.pc and libpng-config to "all:" target in 16 makefiles. + Fixed bug in 16 makefiles: $(DESTDIR)/$(LIBPATH) to $(DESTDIR)$(LIBPATH) + Added missing "\" before closing double quote in makefile.gcmmx. + Plugged various memory leaks; added png_malloc_warn() and png_set_text_2() + functions. +version 1.2.4beta2 [June 25, 2002] + Plugged memory leak of png_ptr->current_text (Matt Holgate). + Check for buffer overflow before reading CRC in pngpread.c (Warwick Allison) + Added -soname to the loader flags in makefile.dec, makefile.sgi, and + makefile.sggcc. + Added "test-installed" target to makefile.linux, makefile.gcmmx, + makefile.sgi, and makefile.sggcc. +version 1.2.4beta3 [June 28, 2002] + Plugged memory leak of row_buf in pngtest.c when there is a png_error(). + Detect buffer overflow in pngpread.c when IDAT is corrupted with extra data. + Added "test-installed" target to makefile.32sunu, makefile.64sunu, + makefile.beos, makefile.darwin, makefile.dec, makefile.macosx, + makefile.solaris, makefile.hpux, makefile.hpgcc, and makefile.so9. +version 1.2.4rc1 and 1.0.14rc1 [July 2, 2002] + Added "test-installed" target to makefile.cygwin and makefile.sco. + Revised pnggccrd.c to be able to back out version 1.0.x via PNG_1_0_X macro. + +version 1.2.4 and 1.0.14 [July 8, 2002] + Changed png_warning() to png_error() when width is too large to process. +version 1.2.4patch01 [July 20, 2002] + Revised makefile.cygwin to use DLL number 12 instead of 13. +version 1.2.5beta1 [August 6, 2002] + Added code to contrib/gregbook/readpng2.c to ignore unused chunks. + Replaced toucan.png in contrib/gregbook (it has been corrupt since 1.0.11) + Removed some stray *.o files from contrib/gregbook. + Changed png_error() to png_warning() about "Too much data" in pngpread.c + and about "Extra compressed data" in pngrutil.c. + Prevent png_ptr->pass from exceeding 7 in png_push_finish_row(). + Updated makefile.hpgcc + Updated png.c and pnggccrd.c handling of return from png_mmx_support() +version 1.2.5beta2 [August 15, 2002] + Only issue png_warning() about "Too much data" in pngpread.c when avail_in + is nonzero. + Updated makefiles to install a separate libpng.so.3 with its own rpath. +version 1.2.5rc1 and 1.0.15rc1 [August 24, 2002] + Revised makefiles to not remove previous minor versions of shared libraries. +version 1.2.5rc2 and 1.0.15rc2 [September 16, 2002] + Revised 13 makefiles to remove "-lz" and "-L$(ZLIBLIB)", etc., from shared + library loader directive. + Added missing "$OBJSDLL" line to makefile.gcmmx. + Added missing "; fi" to makefile.32sunu. +version 1.2.5rc3 and 1.0.15rc3 [September 18, 2002] + Revised libpng-config script. + +version 1.2.5 and 1.0.15 [October 3, 2002] + Revised makefile.macosx, makefile.darwin, makefile.hpgcc, and makefile.hpux, + and makefile.aix. + Relocated two misplaced PNGAPI lines in pngtest.c +version 1.2.6beta1 [October 22, 2002] + Commented out warning about uninitialized mmx_support in pnggccrd.c. + Changed "IBMCPP__" flag to "__IBMCPP__" in pngconf.h. + Relocated two more misplaced PNGAPI lines in pngtest.c + Fixed memory overrun bug in png_do_read_filler() with 16-bit datastreams, + introduced in version 1.0.2. + Revised makefile.macosx, makefile.dec, makefile.aix, and makefile.32sunu. +version 1.2.6beta2 [November 1, 2002] + Added libpng-config "--ldopts" output. + Added "AR=ar" and "ARFLAGS=rc" and changed "ar rc" to "$(AR) $(ARFLAGS)" + in makefiles. +version 1.2.6beta3 [July 18, 2004] + Reverted makefile changes from version 1.2.6beta2 and some of the changes + from version 1.2.6beta1; these will be postponed until version 1.2.7. + Version 1.2.6 is going to be a simple bugfix release. + Changed the one instance of "ln -sf" to "ln -f -s" in each Sun makefile. + Fixed potential overrun in pngerror.c by using strncpy instead of memcpy. + Added "#!/bin/sh" at the top of configure, for recognition of the + 'x' flag under Cygwin (Cosmin). + Optimized vacuous tests that silence compiler warnings, in png.c (Cosmin). + Added support for PNG_USER_CONFIG, in pngconf.h (Cosmin). + Fixed the special memory handler for Borland C under DOS, in pngmem.c + (Cosmin). + Removed some spurious assignments in pngrutil.c (Cosmin). + Replaced 65536 with 65536L, and 0xffff with 0xffffL, to silence warnings + on 16-bit platforms (Cosmin). + Enclosed shift op expressions in parentheses, to silence warnings (Cosmin). + Used proper type png_fixed_point, to avoid problems on 16-bit platforms, + in png_handle_sRGB() (Cosmin). + Added compression_type to png_struct, and optimized the window size + inside the deflate stream (Cosmin). + Fixed definition of isnonalpha(), in pngerror.c and pngrutil.c (Cosmin). + Fixed handling of unknown chunks that come after IDAT (Cosmin). + Allowed png_error() and png_warning() to work even if png_ptr == NULL + (Cosmin). + Replaced row_info->rowbytes with row_bytes in png_write_find_filter() + (Cosmin). + Fixed definition of PNG_LIBPNG_VER_DLLNUM (Simon-Pierre). + Used PNG_LIBPNG_VER and PNG_LIBPNG_VER_STRING instead of the hardcoded + values in png.c (Simon-Pierre, Cosmin). + Initialized png_libpng_ver[] with PNG_LIBPNG_VER_STRING (Simon-Pierre). + Replaced PNG_LIBPNG_VER_MAJOR with PNG_LIBPNG_VER_DLLNUM in png.rc + (Simon-Pierre). + Moved the definition of PNG_HEADER_VERSION_STRING near the definitions + of the other PNG_LIBPNG_VER_... symbols in png.h (Cosmin). + Relocated #ifndef PNGAPI guards in pngconf.h (Simon-Pierre, Cosmin). + Updated scripts/makefile.vc(a)win32 (Cosmin). + Updated the MSVC project (Simon-Pierre, Cosmin). + Updated the Borland C++ Builder project (Cosmin). + Avoided access to asm_flags in pngvcrd.c, if PNG_1_0_X is defined (Cosmin). + Commented out warning about uninitialized mmx_support in pngvcrd.c (Cosmin). + Removed scripts/makefile.bd32 and scripts/pngdef.pas (Cosmin). + Added extra guard around inclusion of Turbo C memory headers, in pngconf.h + (Cosmin). + Renamed projects/msvc/ to projects/visualc6/, and projects/borland/ to + projects/cbuilder5/ (Cosmin). + Moved projects/visualc6/png32ms.def to scripts/pngw32.def, + and projects/visualc6/png.rc to scripts/pngw32.rc (Cosmin). + Added projects/visualc6/pngtest.dsp; removed contrib/msvctest/ (Cosmin). + Changed line endings to DOS style in cbuilder5 and visualc6 files, even + in the tar.* distributions (Cosmin). + Updated contrib/visupng/VisualPng.dsp (Cosmin). + Updated contrib/visupng/cexcept.h to version 2.0.0 (Cosmin). + Added a separate distribution with "configure" and supporting files (Junichi). +version 1.2.6beta4 [July 28, 2004] + Added user ability to change png_size_t via a PNG_SIZE_T macro. + Added png_sizeof() and png_convert_size() functions. + Added PNG_SIZE_MAX (maximum value of a png_size_t variable. + Added check in png_malloc_default() for (size_t)size != (png_uint_32)size + which would indicate an overflow. + Changed sPLT failure action from png_error to png_warning and abandon chunk. + Changed sCAL and iCCP failures from png_error to png_warning and abandon. + Added png_get_uint_31(png_ptr, buf) function. + Added PNG_UINT_32_MAX macro. + Renamed PNG_MAX_UINT to PNG_UINT_31_MAX. + Made png_zalloc() issue a png_warning and return NULL on potential + overflow. + Turn on PNG_NO_ZALLOC_ZERO by default in version 1.2.x + Revised "clobber list" in pnggccrd.c so it will compile under gcc-3.4. + Revised Borland portion of png_malloc() to return NULL or issue + png_error() according to setting of PNG_FLAG_MALLOC_NULL_MEM_OK. + Added PNG_NO_SEQUENTIAL_READ_SUPPORTED macro to conditionally remove + sequential read support. + Added some "#if PNG_WRITE_SUPPORTED" blocks. + Added #ifdef to remove some redundancy in png_malloc_default(). + Use png_malloc instead of png_zalloc to allocate the pallete. +version 1.0.16rc1 and 1.2.6rc1 [August 4, 2004] + Fixed buffer overflow vulnerability in png_handle_tRNS() + Fixed integer arithmetic overflow vulnerability in png_read_png(). + Fixed some harmless bugs in png_handle_sBIT, etc, that would cause + duplicate chunk types to go undetected. + Fixed some timestamps in the -config version + Rearranged order of processing of color types in png_handle_tRNS(). + Added ROWBYTES macro to calculate rowbytes without integer overflow. + Updated makefile.darwin and removed makefile.macosx from scripts directory. + Imposed default one million column, one-million row limits on the image + dimensions, and added png_set_user_limits() function to override them. + Revised use of PNG_SET_USER_LIMITS_SUPPORTED macro. + Fixed wrong cast of returns from png_get_user_width|height_max(). + Changed some "keep the compiler happy" from empty statements to returns, + Revised libpng.txt to remove 1.2.x stuff from the 1.0.x distribution +version 1.0.16rc2 and 1.2.6rc2 [August 7, 2004] + Revised makefile.darwin and makefile.solaris. Removed makefile.macosx. + Revised pngtest's png_debug_malloc() to use png_malloc() instead of + png_malloc_default() which is not supposed to be exported. + Fixed off-by-one error in one of the conversions to PNG_ROWBYTES() in + pngpread.c. Bug was introduced in 1.2.6rc1. + Fixed bug in RGB to RGBX transformation introduced in 1.2.6rc1. + Fixed old bug in RGB to Gray transformation. + Fixed problem with 64-bit compilers by casting arguments to abs() + to png_int_32. + Changed "ln -sf" to "ln -f -s" in three makefiles (solaris, sco, so9). + Changed "HANDLE_CHUNK_*" to "PNG_HANDLE_CHUNK_*" (Cosmin) + Added "-@/bin/rm -f $(DL)/$(LIBNAME).so.$(PNGMAJ)" to 15 *NIX makefiles. + Added code to update the row_info->colortype in png_do_read_filler() (MSB). +version 1.0.16rc3 and 1.2.6rc3 [August 9, 2004] + Eliminated use of "abs()" in testing cHRM and gAMA values, to avoid + trouble with some 64-bit compilers. Created PNG_OUT_OF_RANGE() macro. + Revised documentation of png_set_keep_unknown_chunks(). + Check handle_as_unknown status in pngpread.c, as in pngread.c previously. + Moved "PNG_HANDLE_CHUNK_*" macros out of PNG_INTERNAL section of png.h + Added "rim" definitions for CONST4 and CONST6 in pnggccrd.c +version 1.0.16rc4 and 1.2.6rc4 [August 10, 2004] + Fixed mistake in pngtest.c introduced in 1.2.6rc2 (declaration of + "pinfo" was out of place). +version 1.0.16rc5 and 1.2.6rc5 [August 10, 2004] + Moved "PNG_HANDLE_CHUNK_*" macros out of PNG_ASSEMBLER_CODE_SUPPORTED + section of png.h where they were inadvertently placed in version rc3. + +version 1.2.6 and 1.0.16 [August 15, 2004] + Revised pngtest so memory allocation testing is only done when PNG_DEBUG==1. +version 1.2.7beta1 [August 26, 2004] + Removed unused pngasmrd.h file. + Removed references to uu.net for archived files. Added references to + PNG Spec (second edition) and the PNG ISO/IEC Standard. + Added "test-dd" target in 15 makefiles, to run pngtest in DESTDIR. + Fixed bug with "optimized window size" in the IDAT datastream, that + causes libpng to write PNG files with incorrect zlib header bytes. +version 1.2.7beta2 [August 28, 2004] + Fixed bug with sCAL chunk and big-endian machines (David Munro). + Undid new code added in 1.2.6rc2 to update the color_type in + png_set_filler(). + Added png_set_add_alpha() that updates color type. +version 1.0.17rc1 and 1.2.7rc1 [September 4, 2004] + Revised png_set_strip_filler() to not remove alpha if color_type has alpha. + +version 1.2.7 and 1.0.17 [September 12, 2004] + Added makefile.hp64 + Changed projects/msvc/png32ms.def to scripts/png32ms.def in makefile.cygwin +version 1.2.8beta1 [November 1, 2004] + Fixed bug in png_text_compress() that would fail to complete a large block. + Fixed bug, introduced in libpng-1.2.7, that overruns a buffer during + strip alpha operation in png_do_strip_filler(). + Added PNG_1_2_X definition in pngconf.h + Use #ifdef to comment out png_info_init in png.c and png_read_init in + pngread.c (as of 1.3.0) +version 1.2.8beta2 [November 2, 2004] + Reduce color_type to a nonalpha type after strip alpha operation in + png_do_strip_filler(). +version 1.2.8beta3 [November 3, 2004] + Revised definitions of PNG_MAX_UINT_32, PNG_MAX_SIZE, and PNG_MAXSUM +version 1.2.8beta4 [November 12, 2004] + Fixed (again) definition of PNG_LIBPNG_VER_DLLNUM in png.h (Cosmin). + Added PNG_LIBPNG_BUILD_PRIVATE in png.h (Cosmin). + Set png_ptr->zstream.data_type to Z_BINARY, to avoid unnecessary detection + of data type in deflate (Cosmin). + Deprecated but continue to support SPECIALBUILD and PRIVATEBUILD in favor of + PNG_LIBPNG_BUILD_SPECIAL_STRING and PNG_LIBPNG_BUILD_PRIVATE_STRING. +version 1.2.8beta5 [November 20, 2004] + Use png_ptr->flags instead of png_ptr->transformations to pass + PNG_STRIP_ALPHA info to png_do_strip_filler(), to preserve ABI + compatibility. + Revised handling of SPECIALBUILD, PRIVATEBUILD, + PNG_LIBPNG_BUILD_SPECIAL_STRING and PNG_LIBPNG_BUILD_PRIVATE_STRING. +version 1.2.8rc1 [November 24, 2004] + Moved handling of BUILD macros from pngconf.h to png.h + Added definition of PNG_LIBPNG_BASE_TYPE in png.h, inadvertently + omitted from beta5. + Revised scripts/pngw32.rc + Despammed mailing addresses by masking "@" with "at". + Inadvertently installed a supposedly faster test version of pngrutil.c +version 1.2.8rc2 [November 26, 2004] + Added two missing "\" in png.h + Change tests in pngread.c and pngpread.c to + if (png_ptr->transformations || (png_ptr->flags&PNG_FLAG_STRIP_ALPHA)) + png_do_read_transformations(png_ptr); +version 1.2.8rc3 [November 28, 2004] + Reverted pngrutil.c to version libpng-1.2.8beta5. + Added scripts/makefile.elf with supporting code in pngconf.h for symbol + versioning (John Bowler). +version 1.2.8rc4 [November 29, 2004] + Added projects/visualc7 (Simon-pierre). +version 1.2.8rc5 [November 29, 2004] + Fixed new typo in scripts/pngw32.rc + +version 1.2.8 [December 3, 2004] + Removed projects/visualc7, added projects/visualc71. + +version 1.2.9beta1 [February 21, 2006] + + Initialized some structure members in pngwutil.c to avoid gcc-4.0.0 complaints + Revised man page and libpng.txt to make it clear that one should not call + png_read_end or png_write_end after png_read_png or png_write_png. + Updated references to png-mng-implement mailing list. + Fixed an incorrect typecast in pngrutil.c + Added PNG_NO_READ_SUPPORTED conditional for making a write-only library. + Added PNG_NO_WRITE_INTERLACING_SUPPORTED conditional. + Optimized alpha-inversion loops in pngwtran.c + Moved test for nonzero gamma outside of png_build_gamma_table() in pngrtran.c + Make sure num_trans is <= 256 before copying data in png_set_tRNS(). + Make sure num_palette is <= 256 before copying data in png_set_PLTE(). + Interchanged order of write_swap_alpha and write_invert_alpha transforms. + Added parentheses in the definition of PNG_LIBPNG_BUILD_TYPE (Cosmin). + Optimized zlib window flag (CINFO) in contrib/pngsuite/*.png (Cosmin). + Updated scripts/makefile.bc32 for Borland C++ 5.6 (Cosmin). + Exported png_get_uint_32, png_save_uint_32, png_get_uint_16, png_save_uint_16, + png_get_int_32, png_save_int_32, png_get_uint_31 (Cosmin). + Added type cast (png_byte) in png_write_sCAL() (Cosmin). + Fixed scripts/makefile.cygwin (Christian Biesinger, Cosmin). + Default iTXt support was inadvertently enabled. + +version 1.2.9beta2 [February 21, 2006] + + Check for png_rgb_to_gray and png_gray_to_rgb read transformations before + checking for png_read_dither in pngrtran.c + Revised checking of chromaticity limits to accommodate extended RGB + colorspace (John Denker). + Changed line endings in some of the project files to CRLF, even in the + "Unix" tar distributions (Cosmin). + Made png_get_int_32 and png_save_int_32 always available (Cosmin). + Updated scripts/pngos2.def, scripts/pngw32.def and projects/wince/png32ce.def + with the newly exported functions. + Eliminated distributions without the "configure" script. + Updated INSTALL instructions. + +version 1.2.9beta3 [February 24, 2006] + + Fixed CRCRLF line endings in contrib/visupng/VisualPng.dsp + Made libpng.pc respect EXEC_PREFIX (D. P. Kreil, J. Bowler) + Removed reference to pngasmrd.h from Makefile.am + Renamed CHANGES to ChangeLog. + Renamed LICENSE to COPYING. + Renamed ANNOUNCE to NEWS. + Created AUTHORS file. + +version 1.2.9beta4 [March 3, 2006] + + Changed definition of PKGCONFIG from $prefix/lib to $libdir in configure.ac + Reverted to filenames LICENSE and ANNOUNCE; removed AUTHORS and COPYING. + Removed newline from the end of some error and warning messages. + Removed test for sqrt() from configure.ac and configure. + Made swap tables in pngtrans.c PNG_CONST (Carlo Bramix). + Disabled default iTXt support that was inadvertently enabled in + libpng-1.2.9beta1. + Added "OS2" to list of systems that don't need underscores, in pnggccrd.c + Removed libpng version and date from *.c files. + +version 1.2.9beta5 [March 4, 2006] + Removed trailing blanks from source files. + Put version and date of latest change in each source file, and changed + copyright year accordingly. + More cleanup of configure.ac, Makefile.ac, and associated scripts. + Restored scripts/makefile.elf which was inadvertently deleted. + +version 1.2.9beta6 [March 6, 2006] + Fixed typo (RELEASE) in configuration files. + +version 1.2.9beta7 [March 7, 2006] + Removed libpng.vers and libpng.sym from libpng12_la_SOURCES in Makefile.am + Fixed inconsistent #ifdef's around png_sig_bytes() and png_set_sCAL_s() + in png.h. + Updated makefile.elf as suggested by debian. + Made cosmetic changes to some makefiles, adding LN_SF and other macros. + Made some makefiles accept "exec_prefix". + +version 1.2.9beta8 [March 9, 2006] + Fixed some "#if defined (..." which should be "#if defined(..." + Bug introduced in libpng-1.2.8. + Fixed inconsistency in definition of png_default_read_data() + Restored blank that was lost from makefile.sggcc "clean" target in beta7. + Revised calculation of "current" and "major" for irix in ltmain.sh + Changed "mkdir" to "MKDIR_P" in some makefiles. + Separated PNG_EXPAND and PNG_EXPAND_tRNS. + Added png_set_expand_gray_1_2_4_to_8() and deprecated + png_set_gray_1_2_4_to_8() which also expands tRNS to alpha. + +version 1.2.9beta9 [March 10, 2006] + Include "config.h" in pngconf.h when available. + Added some checks for NULL png_ptr or NULL info_ptr (timeless) + +version 1.2.9beta10 [March 20, 2006] + Removed extra CR from contrib/visualpng/VisualPng.dsw (Cosmin) + Made pnggccrd.c PIC-compliant (Christian Aichinger). + Added makefile.mingw (Wolfgang Glas). + Revised pngconf.h MMX checking. + +version 1.2.9beta11 [March 22, 2006] + Fixed out-of-order declaration in pngwrite.c that was introduced in beta9 + Simplified some makefiles by using LIBSO, LIBSOMAJ, and LIBSOVER macros. + +version 1.2.9rc1 [March 31, 2006] + Defined PNG_USER_PRIVATEBUILD when including "pngusr.h" (Cosmin). + Removed nonsensical assertion check from pngtest.c (Cosmin). + +version 1.2.9 [April 14, 2006] + Revised makefile.beos and added "none" selector in ltmain.sh + +version 1.2.10beta1 [April 15, 2006] + Renamed "config.h" to "png_conf.h" and revised Makefile.am to add + -DPNG_BUILDING_LIBPNG to compile directive, and modified pngconf.h + to include png_conf.h only when PNG_BUILDING_LIBPNG is defined. + +version 1.2.10beta2 [April 15, 2006] + Manually updated Makefile.in and configure. Changed png_conf.h.in + back to config.h. + +version 1.2.10beta3 [April 15, 2006] + Change png_conf.h back to config.h in pngconf.h. + +version 1.2.10beta4 [April 16, 2006] + Change PNG_BUILDING_LIBPNG to PNG_CONFIGURE_LIBPNG in config/Makefile*. + +version 1.2.10beta5 [April 16, 2006] + Added a configure check for compiling assembler code in pnggccrd.c + +version 1.2.10beta6 [April 17, 2006] + Revised the configure check for pnggccrd.c + Moved -DPNG_CONFIGURE_LIBPNG into @LIBPNG_DEFINES@ + Added @LIBPNG_DEFINES@ to arguments when building libpng.sym + +version 1.2.10beta7 [April 18, 2006] + Change "exec_prefix=$prefix" to "exec_prefix=$(prefix)" in makefiles. + +version 1.2.10rc1 [April 19, 2006] + Ensure pngconf.h doesn't define both PNG_USE_PNGGCCRD and PNG_USE_PNGVCRD + Fixed "LN_FS" typo in makefile.sco and makefile.solaris. + +version 1.2.10rc2 [April 20, 2006] + Added a backslash between -DPNG_CONFIGURE_LIBPNG and -DPNG_NO_ASSEMBLER_CODE + in configure.ac and configure + Made the configure warning about versioned symbols less arrogant. + +version 1.2.10rc3 [April 21, 2006] + Added a note in libpng.txt that png_set_sig_bytes(8) can be used when + writing an embedded PNG without the 8-byte signature. + Revised makefiles and configure to avoid making links to libpng.so.* + +version 1.2.10 [April 23, 2006] + Reverted configure to "rc2" state. + +version 1.2.11beta1 [May 31, 2006] + scripts/libpng.pc.in contained "configure" style version info and would + not work with makefiles. + The shared-library makefiles were linking to libpng.so.0 instead of + libpng.so.3 compatibility as the library. + +version 1.2.11beta2 [June 2, 2006] + Increased sprintf buffer from 50 to 52 chars in pngrutil.c to avoid + buffer overflow. + Fixed bug in example.c (png_set_palette_rgb -> png_set_palette_to_rgb) + +version 1.2.11beta3 [June 5, 2006] + Prepended "#! /bin/sh" to ltmail.sh and contrib/pngminus/*.sh (Cosmin). + Removed the accidental leftover Makefile.in~ (Cosmin). + Avoided potential buffer overflow and optimized buffer in + png_write_sCAL(), png_write_sCAL_s() (Cosmin). + Removed the include directories and libraries from CFLAGS and LDFLAGS + in scripts/makefile.gcc (Nelson A. de Oliveira, Cosmin). + +version 1.2.11beta4 [June 6, 2006] + Allow zero-length IDAT chunks after the entire zlib datastream, but not + after another intervening chunk type. + +version 1.0.19rc1, 1.2.11rc1 [June 13, 2006] + Deleted extraneous square brackets from [config.h] in configure.ac + +version 1.0.19rc2, 1.2.11rc2 [June 14, 2006] + Added prototypes for PNG_INCH_CONVERSIONS functions to png.h + Revised INSTALL and autogen.sh + Fixed typo in several makefiles (-W1 should be -Wl) + Added typedef for png_int_32 and png_uint_32 on 64-bit systems. + +version 1.0.19rc3, 1.2.11rc3 [June 15, 2006] + Removed the new typedefs for 64-bit systems (delay until version 1.4.0) + Added one zero element to png_gamma_shift[] array in pngrtran.c to avoid + reading out of bounds. + +version 1.0.19rc4, 1.2.11rc4 [June 15, 2006] + Really removed the new typedefs for 64-bit systems. + +version 1.0.19rc5, 1.2.11rc5 [June 22, 2006] + Removed png_sig_bytes entry from scripts/pngw32.def + +version 1.0.19, 1.2.11 [June 26, 2006] + None. + +version 1.0.20, 1.2.12 [June 27, 2006] + Really increased sprintf buffer from 50 to 52 chars in pngrutil.c to avoid + buffer overflow. + +version 1.2.13beta1 [October 2, 2006] + Removed AC_FUNC_MALLOC from configure.ac + Work around Intel-Mac compiler bug by setting PNG_NO_MMX_CODE in pngconf.h + Change "logical" to "bitwise" throughout documentation. + Detect and fix attempt to write wrong iCCP profile length. + +version 1.0.21, 1.2.13 [November 14, 2006] + Fix potential buffer overflow in sPLT chunk handler. + Fix Makefile.am to not try to link to noexistent files. + Check all exported functions for NULL png_ptr. + +version 1.2.14beta1 [November 17, 2006] + Relocated three misplaced tests for NULL png_ptr. + Built Makefile.in with automake-1.9.6 instead of 1.9.2. + Build configure with autoconf-2.60 instead of 2.59 + +version 1.2.14beta2 [November 17, 2006] + Added some typecasts in png_zalloc(). + +version 1.2.14rc1 [November 20, 2006] + Changed "strtod" to "png_strtod" in pngrutil.c + +version 1.0.22, 1.2.14 [November 27, 2006] + Added missing "$(srcdir)" in Makefile.am and Makefile.in + +version 1.2.15beta1 [December 3, 2006] + Generated configure with autoconf-2.61 instead of 2.60 + Revised configure.ac to update libpng.pc and libpng-config. + +version 1.2.15beta2 [December 3, 2006] + Always export MMX asm functions, just stubs if not building pnggccrd.c + +version 1.2.15beta3 [December 4, 2006] + Add "png_bytep" typecast to profile while calculating length in pngwutil.c + +version 1.2.15beta4 [December 7, 2006] + Added scripts/CMakeLists.txt + Changed PNG_NO_ASSEMBLER_CODE to PNG_NO_MMX_CODE in scripts, like 1.4.0beta + +version 1.2.15beta5 [December 7, 2006] + Changed some instances of PNG_ASSEMBLER_* to PNG_MMX_* in pnggccrd.c + Revised scripts/CMakeLists.txt + +version 1.2.15beta6 [December 13, 2006] + Revised scripts/CMakeLists.txt and configure.ac + +version 1.2.15rc1 [December 18, 2006] + Revised scripts/CMakeLists.txt + +version 1.2.15rc2 [December 21, 2006] + Added conditional #undef jmpbuf in pngtest.c to undo #define in AIX headers. + Added scripts/makefile.nommx + +version 1.2.15rc3 [December 25, 2006] + Fixed shared library numbering error that was introduced in 1.2.15beta6. + +version 1.2.15rc4 [December 27, 2006] + Fixed handling of rgb_to_gray when png_ptr->color.gray isn't set. + +version 1.2.15rc5 [December 31, 2006] + Revised handling of rgb_to_gray. + +version 1.2.15 [January 5, 2007] + Added some (unsigned long) typecasts in pngtest.c to avoid printing errors. + +version 1.2.16beta1 [January 6, 2007] + Fix bugs in makefile.nommx + +version 1.2.16beta2 [January 16, 2007] + Revised scripts/CMakeLists.txt + +version 1.2.16 [January 31, 2007] + No changes. + +version 1.2.17beta1 [March 6, 2007] + Revised scripts/CMakeLists.txt to install both shared and static libraries. + Deleted a redundant line from pngset.c. + +version 1.2.17beta2 [April 26, 2007] + Relocated misplaced test for png_ptr == NULL in pngpread.c + Change "==" to "&" for testing PNG_RGB_TO_GRAY_ERR & PNG_RGB_TO_GRAY_WARN + flags. + Changed remaining instances of PNG_ASSEMBLER_* to PNG_MMX_* + Added pngerror() when write_IHDR fails in deflateInit2(). + Added "const" to some array declarations. + Mention examples of libpng usage in the libpng*.txt and libpng.3 documents. + +version 1.2.17rc1 [May 4, 2007] + No changes. + +version 1.2.17rc2 [May 8, 2007] + Moved several PNG_HAVE_* macros out of PNG_INTERNAL because applications + calling set_unknown_chunk_location() need them. + Changed transformation flag from PNG_EXPAND_tRNS to PNG_EXPAND in + png_set_expand_gray_1_2_4_to_8(). + Added png_ptr->unknown_chunk to hold working unknown chunk data, so it + can be free'ed in case of error. Revised unknown chunk handling in + pngrutil.c and pngpread.c to use this structure. + +version 1.2.17rc3 [May 8, 2007] + Revised symbol-handling in configure script. + +version 1.2.17rc4 [May 10, 2007] + Revised unknown chunk handling to avoid storing unknown critical chunks. + +version 1.0.25 [May 15, 2007] +version 1.2.17 [May 15, 2007] + Added "png_ptr->num_trans=0" before error return in png_handle_tRNS, + to eliminate a vulnerability (CVE-2007-2445, CERT VU#684664) + +version 1.0.26 [May 15, 2007] +version 1.2.18 [May 15, 2007] + Reverted the libpng-1.2.17rc3 change to symbol-handling in configure script + +version 1.2.19beta1 [May 18, 2007] + Changed "const static" to "static PNG_CONST" everywhere, mostly undoing + change of libpng-1.2.17beta2. Changed other "const" to "PNG_CONST" + Changed some handling of unused parameters, to avoid compiler warnings. + "if (unused == NULL) return;" becomes "unused = unused". + +version 1.2.19beta2 [May 18, 2007] + Only use the valid bits of tRNS value in png_do_expand() (Brian Cartier) + +version 1.2.19beta3 [May 19, 2007] + Add some "png_byte" typecasts in png_check_keyword() and write new_key + instead of key in zTXt chunk (Kevin Ryde). + +version 1.2.19beta4 [May 21, 2007] + Add png_snprintf() function and use it in place of sprint() for improved + defense against buffer overflows. + +version 1.2.19beta5 [May 21, 2007] + Fixed png_handle_tRNS() to only use the valid bits of tRNS value. + Changed handling of more unused parameters, to avoid compiler warnings. + Removed some PNG_CONST in pngwutil.c to avoid compiler warnings. + +version 1.2.19beta6 [May 22, 2007] + Added some #ifdef PNG_MMX_CODE_SUPPORTED where needed in pngvcrd.c + Added a special "_MSC_VER" case that defines png_snprintf to _snprintf + +version 1.2.19beta7 [May 22, 2007] + Squelched png_squelch_warnings() in pnggccrd.c and added + an #ifdef PNG_MMX_CODE_SUPPORTED block around the declarations that caused + the warnings that png_squelch_warnings was squelching. + +version 1.2.19beta8 [May 22, 2007] + Removed __MMX__ from test in pngconf.h. + +version 1.2.19beta9 [May 23, 2007] + Made png_squelch_warnings() available via PNG_SQUELCH_WARNINGS macro. + Revised png_squelch_warnings() so it might work. + Updated makefile.sgcc and makefile.solaris; added makefile.solaris-x86. + +version 1.2.19beta10 [May 24, 2007] + Resquelched png_squelch_warnings(), use "__attribute__((used))" instead. + +version 1.4.0beta1 [April 20, 2006] + Enabled iTXt support (changes png_struct, thus requires so-number change). + Cleaned up PNG_ASSEMBLER_CODE_SUPPORTED vs PNG_MMX_CODE_SUPPORTED + Eliminated PNG_1_0_X and PNG_1_2_X macros. + Removed deprecated functions png_read_init, png_write_init, png_info_init, + png_permit_empty_plte, png_set_gray_1_2_4_to_8, png_check_sig, and + removed the deprecated macro PNG_MAX_UINT. + Moved "PNG_INTERNAL" parts of png.h and pngconf.h into pngintrn.h + Removed many WIN32_WCE #ifdefs (Cosmin). + Reduced dependency on C-runtime library when on Windows (Simon-Pierre) + Replaced sprintf() with png_sprintf() (Simon-Pierre) + +version 1.4.0beta2 [April 20, 2006] + Revised makefiles and configure to avoid making links to libpng.so.* + Moved some leftover MMX-related defines from pngconf.h to pngintrn.h + Updated scripts/pngos2.def, pngw32.def, and projects/wince/png32ce.def + +version 1.4.0beta3 [May 10, 2006] + Updated scripts/pngw32.def to comment out MMX functions. + Added PNG_NO_GET_INT_32 and PNG_NO_SAVE_INT_32 macros. + Scripts/libpng.pc.in contained "configure" style version info and would + not work with makefiles. + Revised pngconf.h and added pngconf.h.in, so makefiles and configure can + pass defines to libpng and applications. + +version 1.4.0beta4 [May 11, 2006] + Revised configure.ac, Makefile.am, and many of the makefiles to write + their defines in pngconf.h. + +version 1.4.0beta5 [May 15, 2006] + Added a missing semicolon in Makefile.am and Makefile.in + Deleted extraneous square brackets from configure.ac + +version 1.4.0beta6 [June 2, 2006] + Increased sprintf buffer from 50 to 52 chars in pngrutil.c to avoid + buffer overflow. + Changed sonum from 0 to 1. + Removed unused prototype for png_check_sig() from png.h + +version 1.4.0beta7 [June 16, 2006] + Exported png_write_sig (Cosmin). + Optimized buffer in png_handle_cHRM() (Cosmin). + Set pHYs = 2835 x 2835 pixels per meter, and added + sCAL = 0.352778e-3 x 0.352778e-3 meters, in pngtest.png (Cosmin). + Added png_set_benign_errors(), png_benign_error(), png_chunk_benign_error(). + Added typedef for png_int_32 and png_uint_32 on 64-bit systems. + Added "(unsigned long)" typecast on png_uint_32 variables in printf lists. + +version 1.4.0beta8 [June 22, 2006] + Added demonstration of user chunk support in pngtest.c, to support the + public sTER chunk and a private vpAg chunk. + +version 1.4.0beta9 [July 3, 2006] + Removed ordinals from scripts/pngw32.def and removed png_info_int and + png_set_gray_1_2_4_to_8 entries. + Inline call of png_get_uint_32() in png_get_uint_31(). + Use png_get_uint_31() to get vpAg width and height in pngtest.c + Removed WINCE and Netware projects. + Removed standalone Y2KINFO file. + +version 1.4.0beta10 [July 12, 2006] + Eliminated automatic copy of pngconf.h to pngconf.h.in from configure and + some makefiles, because it was not working reliably. Instead, distribute + pngconf.h.in along with pngconf.h and cause configure and some of the + makefiles to update pngconf.h from pngconf.h.in. + Added pngconf.h to DEPENDENCIES in Makefile.am + +version 1.4.0beta11 [August 19, 2006] + Removed AC_FUNC_MALLOC from configure.ac. + Added a warning when writing iCCP profile with mismatched profile length. + Patched pnggccrd.c to assemble on x86_64 platforms. + Moved chunk header reading into a separate function png_read_chunk_header() + in pngrutil.c. The chunk header (len+sig) is now serialized in a single + operation (Cosmin). + Implemented support for I/O states. Added png_ptr member io_state, and + functions png_get_io_chunk_name() and png_get_io_state() in pngget.c + (Cosmin). + Added png_get_io_chunk_name and png_get_io_state to scripts/*.def (Cosmin). + Renamed scripts/pngw32.* to scripts/pngwin.* (Cosmin). + Removed the include directories and libraries from CFLAGS and LDFLAGS + in scripts/makefile.gcc (Cosmin). + Used png_save_uint_32() to set vpAg width and height in pngtest.c (Cosmin). + Cast to proper type when getting/setting vpAg units in pngtest.c (Cosmin). + Added pngintrn.h to the Visual C++ projects (Cosmin). + Removed scripts/list (Cosmin). + Updated copyright year in scripts/pngwin.def (Cosmin). + Removed PNG_TYPECAST_NULL and used standard NULL consistently (Cosmin). + Disallowed the user to redefine png_size_t, and enforced a consistent use + of png_size_t across libpng (Cosmin). + Changed the type of png_ptr->rowbytes, PNG_ROWBYTES() and friends + to png_size_t (Cosmin). + Removed png_convert_size() and replaced png_sizeof with sizeof (Cosmin). + Removed some unnecessary type casts (Cosmin). + Changed prototype of png_get_compression_buffer_size() and + png_set_compression_buffer_size() to work with png_size_t instead of + png_uint_32 (Cosmin). + Removed png_memcpy_check() and png_memset_check() (Cosmin). + Fixed a typo (png_byte --> png_bytep) in libpng.3 and libpng.txt (Cosmin). + Clarified that png_zalloc() does not clear the allocated memory, + and png_zalloc() and png_zfree() cannot be PNGAPI (Cosmin). + Renamed png_mem_size_t to png_alloc_size_t, fixed its definition in + pngconf.h, and used it in all memory allocation functions (Cosmin). + Renamed pngintrn.h to pngpriv.h, added a comment at the top of the file + mentioning that the symbols declared in that file are private, and + updated the scripts and the Visual C++ projects accordingly (Cosmin). + Removed circular references between pngconf.h and pngconf.h.in in + scripts/makefile.vc*win32 (Cosmin). + Removing trailing '.' from the warning and error messages (Cosmin). + Added pngdefs.h that is built by makefile or configure, instead of + pngconf.h.in (Glenn). + Detect and fix attempt to write wrong iCCP profile length. + +version 1.4.0beta12 [October 19, 2006] + Changed "logical" to "bitwise" in the documentation. + Work around Intel-Mac compiler bug by setting PNG_NO_MMX_CODE in pngconf.h + Add a typecast to stifle compiler warning in pngrutil.c + +version 1.4.0beta13 [November 10, 2006] + Fix potential buffer overflow in sPLT chunk handler. + Fix Makefile.am to not try to link to noexistent files. + +version 1.4.0beta14 [November 15, 2006] + Check all exported functions for NULL png_ptr. + +version 1.4.0beta15 [November 17, 2006] + Relocated two misplaced tests for NULL png_ptr. + Built Makefile.in with automake-1.9.6 instead of 1.9.2. + Build configure with autoconf-2.60 instead of 2.59 + Add "install: all" in Makefile.am so "configure; make install" will work. + +version 1.4.0beta16 [November 17, 2006] + Added a typecast in png_zalloc(). + +version 1.4.0beta17 [December 4, 2006] + Changed "new_key[79] = '\0';" to "(*new_key)[79] = '\0';" in pngwutil.c + Add "png_bytep" typecast to profile while calculating length in pngwutil.c + +version 1.4.0beta18 [December 7, 2006] + Added scripts/CMakeLists.txt + +version 1.4.0beta19 [May 16, 2007] + Revised scripts/CMakeLists.txt + Rebuilt configure and Makefile.in with newer tools. + Added conditional #undef jmpbuf in pngtest.c to undo #define in AIX headers. + Added scripts/makefile.nommx + +version 1.4.0beta20 [July 9, 2008] + Moved several PNG_HAVE_* macros from pngpriv.h to png.h because applications + calling set_unknown_chunk_location() need them. + Moved several macro definitions from pngpriv.h to pngconf.h + Merge with changes to the 1.2.X branch, as of 1.2.30beta04. + Deleted all use of the MMX assembler code and Intel-licensed optimizations. + Revised makefile.mingw + +version 1.4.0beta21 [July 21, 2008] + Moved local array "chunkdata" from pngrutil.c to the png_struct, so + it will be freed by png_read_destroy() in case of a read error (Kurt + Christensen). + +version 1.4.0beta22 [July 21, 2008] + Change "purpose" and "buffer" to png_ptr->chunkdata to avoid memory leaking. + +version 1.4.0beta23 [July 22, 2008] + Change "chunkdata = NULL" to "png_ptr->chunkdata = NULL" several places in + png_decompress_chunk(). + +version 1.4.0beta24 [July 25, 2008] + Change all remaining "chunkdata" to "png_ptr->chunkdata" in + png_decompress_chunk(), and remove "chunkdata" from parameter list. + Put a call to png_check_chunk_name() in png_read_chunk_header(). + Revised png_check_chunk_name() to reject a name with a lowercase 3rd byte. + Removed two calls to png_check_chunk_name() occuring later in the process. + Define PNG_NO_ERROR_NUMBERS by default in pngconf.h + +version 1.4.0beta25 [July 30, 2008] + Added a call to png_check_chunk_name() in pngpread.c + Reverted png_check_chunk_name() to accept a name with a lowercase 3rd byte. + Added png_push_have_buffer() function to pngpread.c + Eliminated PNG_BIG_ENDIAN_SUPPORTED and associated png_get_* macros. + Made inline expansion of png_get_*() optional with PNG_USE_READ_MACROS. + Eliminated all PNG_USELESS_TESTS and PNG_CORRECT_PALETTE_SUPPORTED code. + Synced contrib directory and configure files with libpng-1.2.30beta06. + Eliminated no-longer-used pngdefs.h (but it's still built in the makefiles) + Relocated a misplaced "#endif /* PNG_NO_WRITE_FILTER */" in pngwutil.c + +version 1.4.0beta26 [August 4, 2008] + Removed png_push_have_buffer() function in pngpread.c. It increased the + compiled library size slightly. + Changed "-Wall" to "-W -Wall" in the CFLAGS in all makefiles (Cosmin Truta) + Declared png_ptr "volatile" in pngread.c and pngwrite.c to avoid warnings. + Updated contrib/visupng/cexcept.h to version 2.0.1 + Added PNG_LITERAL_CHARACTER macros for #, [, and ]. + +version 1.4.0beta27 [August 5, 2008] + Revised usage of PNG_LITERAL_SHARP in pngerror.c. + Moved newline character from individual png_debug messages into the + png_debug macros. + Allow user to #define their own png_debug, png_debug1, and png_debug2. + +version 1.4.0beta28 [August 5, 2008] + Revised usage of PNG_LITERAL_SHARP in pngerror.c. + Added PNG_STRING_NEWLINE macro + +version 1.4.0beta29 [August 9, 2008] + Revised usage of PNG_STRING_NEWLINE to work on non-ISO compilers. + Added PNG_STRING_COPYRIGHT macro. + Added non-ISO versions of png_debug macros. + +version 1.4.0beta30 [August 14, 2008] + Added premultiplied alpha feature (Volker Wiendl). + +version 1.4.0beta31 [August 18, 2008] + Moved png_set_premultiply_alpha from pngtrans.c to pngrtran.c + Removed extra crc check at the end of png_handle_cHRM(). Bug introduced + in libpng-1.4.0beta20. + +version 1.4.0beta32 [August 19, 2008] + Added PNG_WRITE_FLUSH_SUPPORTED block around new png_flush() call. + Revised PNG_NO_STDIO version of png_write_flush() + +version 1.4.0beta33 [August 20, 2008] + Added png_get|set_chunk_cache_max() to limit the total number of sPLT, + text, and unknown chunks that can be stored. + +version 1.4.0beta34 [September 6, 2008] + Shortened tIME_string to 29 bytes in pngtest.c + Fixed off-by-one error introduced in png_push_read_zTXt() function in + libpng-1.2.30beta04/pngpread.c (Harald van Dijk) + +version 1.4.0beta35 [October 6, 2008] + Changed "trans_values" to "trans_color". + Changed so-number from 0 to 14. Some OS do not like 0. + Revised makefile.darwin to fix shared library numbering. + Change png_set_gray_1_2_4_to_8() to png_set_expand_gray_1_2_4_to_8() + in example.c (debian bug report) + +version 1.4.0beta36 [October 25, 2008] + Sync with tEXt vulnerability fix in libpng-1.2.33rc02. + +version 1.4.0beta37 [November 13, 2008] + Added png_check_cHRM in png.c and moved checking from pngget.c, pngrutil.c, + and pngwrite.c + +version 1.4.0beta38 [November 22, 2008] + Added check for zero-area RGB cHRM triangle in png_check_cHRM() and + png_check_cHRM_fixed(). + +version 1.4.0beta39 [November 23, 2008] + Revised png_warning() to write its message on standard output by default + when warning_fn is NULL. + +version 1.4.0beta40 [November 24, 2008] + Eliminated png_check_cHRM(). Instead, always use png_check_cHRM_fixed(). + In png_check_cHRM_fixed(), ensure white_y is > 0, and removed redundant + check for all-zero coordinates that is detected by the triangle check. + +version 1.4.0beta41 [November 26, 2008] + Fixed string vs pointer-to-string error in png_check_keyword(). + Rearranged test expressions in png_check_cHRM_fixed() to avoid internal + overflows. + Added PNG_NO_CHECK_cHRM conditional. + +version 1.4.0beta42, 43 [December 1, 2008] + Merge png_debug with version 1.2.34beta04. + +version 1.4.0beta44 [December 6, 2008] + Removed redundant check for key==NULL before calling png_check_keyword() + to ensure that new_key gets initialized and removed extra warning + (Merge with version 1.2.34beta05 -- Arvan Pritchard). + +version 1.4.0beta45 [December 9, 2008] + In png_write_png(), respect the placement of the filler bytes in an earlier + call to png_set_filler() (Jim Barry). + +version 1.4.0beta46 [December 10, 2008] + Undid previous change and added PNG_TRANSFORM_STRIP_FILLER_BEFORE and + PNG_TRANSFORM_STRIP_FILLER_AFTER conditionals and deprecated + PNG_TRANSFORM_STRIP_FILLER (Jim Barry). + +version 1.4.0beta47 [December 15, 2008] + Support for dithering was disabled by default, because it has never + been well tested and doesn't work very well. The code has not + been removed, however, and can be enabled by building libpng with + PNG_READ_DITHER_SUPPORTED defined. + +version 1.4.0beta48 [February 14, 2009] + Added new exported function png_calloc(). + Combined several instances of png_malloc(); png_memset() into png_calloc(). + Removed prototype for png_freeptr() that was added in libpng-1.4.0beta24 + but was never defined. + +version 1.4.0beta49 [February 28, 2009] + Added png_fileno() macro to pngconf.h, used in pngwio.c + Corrected order of #ifdef's in png_debug definition in png.h + Fixed bug introduced in libpng-1.4.0beta48 with the memset arguments + for pcal_params. + Fixed order of #ifdef directives in the png_debug defines in png.h + (bug introduced in libpng-1.2.34/1.4.0beta29). + Revised comments in png_set_read_fn() and png_set_write_fn(). + +version 1.4.0beta50 [March 18, 2009] + Use png_calloc() instead of png_malloc() to allocate big_row_buf when + reading an interlaced file, to avoid a possible UMR. + Undid revision of PNG_NO_STDIO version of png_write_flush(). Users + having trouble with fflush() can build with PNG_NO_WRITE_FLUSH defined + or supply their own flush_fn() replacement. + Revised libpng*.txt and png.h documentation about use of png_write_flush() + and png_set_write_fn(). + Removed fflush() from pngtest.c. + Added "#define PNG_NO_WRITE_FLUSH" to contrib/pngminim/encoder/pngusr.h + +version 1.4.0beta51 [March 21, 2009] + Removed new png_fileno() macro from pngconf.h . + +version 1.4.0beta52 [March 27, 2009] + Relocated png_do_chop() ahead of building gamma tables in pngrtran.c + This avoids building 16-bit gamma tables unnecessarily. + Removed fflush() from pngtest.c. + Added "#define PNG_NO_WRITE_FLUSH" to contrib/pngminim/encoder/pngusr.h + Added a section on differences between 1.0.x and 1.2.x to libpng.3/libpng.txt + +version 1.4.0beta53 [April 1, 2009] + Removed some remaining MMX macros from pngpriv.h + Fixed potential memory leak of "new_name" in png_write_iCCP() (Ralph Giles) + +version 1.4.0beta54 [April 13, 2009] + Added "ifndef PNG_SKIP_SETJMP_CHECK" block in pngconf.h to allow + application code writers to bypass the check for multiple inclusion + of setjmp.h when they know that it is safe to ignore the situation. + Eliminated internal use of setjmp() in pngread.c and pngwrite.c + Reordered ancillary chunks in pngtest.png to be the same as what + pngtest now produces, and made some cosmetic changes to pngtest output. + Eliminated deprecated png_read_init_3() and png_write_init_3() functions. + +version 1.4.0beta55 [April 15, 2009] + Simplified error handling in pngread.c and pngwrite.c by putting + the new png_read_cleanup() and png_write_cleanup() functions inline. + +version 1.4.0beta56 [April 25, 2009] + Renamed "user_chunk_data" to "my_user_chunk_data" in pngtest.c to suppress + "shadowed declaration" warning from gcc-4.3.3. + Renamed "gamma" to "png_gamma" in pngset.c to avoid "shadowed declaration" + warning about a global "gamma" variable in math.h on some platforms. + +version 1.4.0beta57 [May 2, 2009] + Removed prototype for png_freeptr() that was added in libpng-1.4.0beta24 + but was never defined (again). + Rebuilt configure scripts with autoconf-2.63 instead of 2.62 + Removed pngprefs.h and MMX from makefiles + +version 1.4.0beta58 [May 14, 2009] + Changed pngw32.def to pngwin.def in makefile.mingw (typo was introduced + in beta57). + Clarified usage of sig_bit versus sig_bit_p in example.c (Vincent Torri) + +version 1.4.0beta59 [May 15, 2009] + Reformated sources in libpng style (3-space intentation, comment format) + Fixed typo in libpng docs (PNG_FILTER_AVE should be PNG_FILTER_AVG) + Added sections about the git repository and our coding style to the + documentation + Relocated misplaced #endif in pngwrite.c, sCAL chunk handler. + +version 1.4.0beta60 [May 19, 2009] + Conditionally compile png_read_finish_row() which is not used by + progressive readers. + Added contrib/pngminim/preader to demonstrate building minimal progressive + decoder, based on contrib/gregbook with embedded libpng and zlib. + +version 1.4.0beta61 [May 20, 2009] + In contrib/pngminim/*, renamed "makefile.std" to "makefile", since there + is only one makefile in those directories, and revised the README files + accordingly. + More reformatting of comments, mostly to capitalize sentences. + +version 1.4.0beta62 [June 2, 2009] + Added "#define PNG_NO_WRITE_SWAP" to contrib/pngminim/encoder/pngusr.h + and "define PNG_NO_READ_SWAP" to decoder/pngusr.h and preader/pngusr.h + Reformatted several remaining "else statement" into two lines. + Added a section to the libpng documentation about using png_get_io_ptr() + in configure scripts to detect the presence of libpng. + +version 1.4.0beta63 [June 15, 2009] + Revised libpng*.txt and libpng.3 to mention calling png_set_IHDR() + multiple times and to specify the sample order in the tRNS chunk, + because the ISO PNG specification has a typo in the tRNS table. + Changed several PNG_UNKNOWN_CHUNK_SUPPORTED to + PNG_HANDLE_AS_UNKNOWN_SUPPORTED, to make the png_set_keep mechanism + available for ignoring known chunks even when not saving unknown chunks. + Adopted preference for consistent use of "#ifdef" and "#ifndef" versus + "#if defined()" and "if !defined()" where possible. + +version 1.4.0beta64 [June 24, 2009] + Eliminated PNG_LEGACY_SUPPORTED code. + Moved the various unknown chunk macro definitions outside of the + PNG_READ|WRITE_ANCILLARY_CHUNK_SUPPORTED blocks. + +version 1.4.0beta65 [June 26, 2009] + Added a reference to the libpng license in each file. + +version 1.4.0beta66 [June 27, 2009] + Refer to the libpng license instead of the libpng license in each file. + +version 1.4.0beta67 [July 6, 2009] + Relocated INVERT_ALPHA within png_read_png() and png_write_png(). + Added high-level API transform PNG_TRANSFORM_GRAY_TO_RGB. + Added an "xcode" project to the projects directory (Alam Arias). + +version 1.4.0beta68 [July 19, 2009] + Avoid some tests in filter selection in pngwutil.c + +version 1.4.0beta69 [July 25, 2009] + Simplified the new filter-selection test. This runs faster in the + common "PNG_ALL_FILTERS" and PNG_FILTER_NONE cases. + Removed extraneous declaration from the new call to png_read_gray_to_rgb() + (bug introduced in libpng-1.4.0beta67). + Fixed up xcode project (Alam Arias) + Added a prototype for png_64bit_product() in png.c + +version 1.4.0beta70 [July 27, 2009] + Avoid a possible NULL dereference in debug build, in png_set_text_2(). + (bug introduced in libpng-0.95, discovered by Evan Rouault) + +version 1.4.0beta71 [July 29, 2009] + Rebuilt configure scripts with autoconf-2.64. + +version 1.4.0beta72 [August 1, 2009] + Replaced *.tar.lzma with *.tar.xz in distribution. Get the xz codec + from . + +version 1.4.0beta73 [August 1, 2009] + Reject attempt to write iCCP chunk with negative embedded profile length + (JD Chen) + +version 1.4.0beta74 [August 8, 2009] + Changed png_ptr and info_ptr member "trans" to "trans_alpha". + +version 1.4.0beta75 [August 21, 2009] + Removed an extra png_debug() recently added to png_write_find_filter(). + Fixed incorrect #ifdef in pngset.c regarding unknown chunk support. + +version 1.4.0beta76 [August 22, 2009] + Moved an incorrectly located test in png_read_row() in pngread.c + +version 1.4.0beta77 [August 27, 2009] + Removed lpXYZ.tar.bz2 (with CRLF), KNOWNBUG, libpng-x.y.z-KNOWNBUG.txt, + and the "noconfig" files from the distribution. + Moved CMakeLists.txt from scripts into the main libpng directory. + Various bugfixes and improvements to CMakeLists.txt (Philip Lowman) + +version 1.4.0beta78 [August 31, 2009] + Converted all PNG_NO_* tests to PNG_*_SUPPORTED everywhere except pngconf.h + Eliminated PNG_NO_FREE_ME and PNG_FREE_ME_SUPPORTED macros. + Use png_malloc plus a loop instead of png_calloc() to initialize + row_pointers in png_read_png(). + +version 1.4.0beta79 [September 1, 2009] + Eliminated PNG_GLOBAL_ARRAYS and PNG_LOCAL_ARRAYS; always use local arrays. + Eliminated PNG_CALLOC_SUPPORTED macro and always provide png_calloc(). + +version 1.4.0beta80 [September 17, 2009] + Removed scripts/libpng.icc + Changed typecast of filler from png_byte to png_uint_16 in png_set_filler(). + (Dennis Gustafsson) + Fixed typo introduced in beta78 in pngtest.c ("#if def " should be "#ifdef ") + +version 1.4.0beta81 [September 23, 2009] + Eliminated unused PNG_FLAG_FREE_* defines from pngpriv.h + Expanded TAB characters in pngrtran.c + Removed PNG_CONST from all "PNG_CONST PNG_CHNK" declarations to avoid + compiler complaints about doubly declaring things "const". + Changed all "#if [!]defined(X)" to "if[n]def X" where possible. + Eliminated unused png_ptr->row_buf_size + +version 1.4.0beta82 [September 25, 2009] + Moved redundant IHDR checking into new png_check_IHDR() in png.c + and report all errors found in the IHDR data. + Eliminated useless call to png_check_cHRM() from pngset.c + +version 1.4.0beta83 [September 25, 2009] + Revised png_check_IHDR() to eliminate bogus complaint about filter_type. + +version 1.4.0beta84 [September 30, 2009] + Fixed some inconsistent indentation in pngconf.h + Revised png_check_IHDR() to add a test for width variable less than 32-bit. + +version 1.4.0beta85 [October 1, 2009] + Revised png_check_IHDR() again, to check info_ptr members instead of + the contents of the returned parameters. + +version 1.4.0beta86 [October 9, 2009] + Updated the "xcode" project (Alam Arias). + Eliminated a shadowed declaration of "pp" in png_handle_sPLT(). + +version 1.4.0rc01 [October 19, 2009] + Trivial cosmetic changes. + +version 1.4.0beta87 [October 30, 2009] + Moved version 1.4.0 back into beta. + +version 1.4.0beta88 [October 30, 2009] + Revised libpng*.txt section about differences between 1.2.x and 1.4.0 + because most of the new features have now been ported back to 1.2.41 + +version 1.4.0beta89 [November 1, 2009] + More bugfixes and improvements to CMakeLists.txt (Philip Lowman) + Removed a harmless extra png_set_invert_alpha() from pngwrite.c + Apply png_user_chunk_cache_max within png_decompress_chunk(). + Merged libpng-1.2.41.txt with libpng-1.4.0.txt where appropriate. + +version 1.4.0beta90 [November 2, 2009] + Removed all remaining WIN32_WCE #ifdefs except those involving the + time.h "tm" structure + +version 1.4.0beta91 [November 3, 2009] + Updated scripts/pngw32.def and projects/wince/png32ce.def + Copied projects/wince/png32ce.def to the scripts directory. + Added scripts/makefile.wce + Patched ltmain.sh for wince support. + Added PNG_CONVERT_tIME_SUPPORTED macro. + +version 1.4.0beta92 [November 4, 2009] + Make inclusion of time.h in pngconf.h depend on PNG_CONVERT_tIME_SUPPORTED + Make #define PNG_CONVERT_tIME_SUPPORTED depend on PNG_WRITE_tIME_SUPPORTED + Revised libpng*.txt to describe differences from 1.2.40 to 1.4.0 (instead + of differences from 1.2.41 to 1.4.0) + +version 1.4.0beta93 [November 7, 2009] + Added PNG_DEPSTRUCT, PNG_DEPRECATED, PNG_USE_RESULT, PNG_NORETURN, and + PNG_ALLOCATED macros to detect deprecated direct access to the + png_struct or info_struct members and other deprecated usage in + applications (John Bowler). + Updated scripts/makefile* to add "-DPNG_CONFIGURE_LIBPNG" to CFLAGS, + to prevent warnings about direct access to png structs by libpng + functions while building libpng. They need to be tested, especially + those using compilers other than gcc. + Updated projects/visualc6 and visualc71 with "/d PNG_CONFIGURE_LIBPNG". + They should work but still need to be updated to remove + references to pnggccrd.c or pngvcrd.c and ASM building. + Added README.txt to the beos, cbuilder5, netware, and xcode projects warning + that they need to be updated, to remove references to pnggccrd.c and + pngvcrd.c and to depend on pngpriv.h + Removed three direct references to read_info_ptr members in pngtest.c + that were detected by the new PNG_DEPSTRUCT macro. + Moved the png_debug macro definitions and the png_read_destroy(), + png_write_destroy() and png_far_to_near() prototypes from png.h + to pngpriv.h (John Bowler) + Moved the synopsis lines for png_read_destroy(), png_write_destroy() + png_debug(), png_debug1(), and png_debug2() from libpng.3 to libpngpf.3. + +version 1.4.0beta94 [November 9, 2009] + Removed the obsolete, unused pnggccrd.c and pngvcrd.c files. + Updated CMakeLists.txt to add "-DPNG_CONFIGURE_LIBPNG" to the definitions. + Removed dependency of pngtest.o on pngpriv.h in the makefiles. + Only #define PNG_DEPSTRUCT, etc. in pngconf.h if not already defined. + +version 1.4.0beta95 [November 10, 2009] + Changed png_check_sig() to !png_sig_cmp() in contrib programs. + Added -DPNG_CONFIGURE_LIBPNG to contrib/pngminm/*/makefile + Changed png_check_sig() to !png_sig_cmp() in contrib programs. + Corrected the png_get_IHDR() call in contrib/gregbook/readpng2.c + Changed pngminim/*/gather.sh to stop trying to remove pnggccrd.c and pngvcrd.c + Added dependency on pngpriv.h in contrib/pngminim/*/makefile + +version 1.4.0beta96 [November 12, 2009] + Renamed scripts/makefile.wce to scripts/makefile.cegcc + Revised Makefile.am to use libpng.sys while building libpng.so + so that only PNG_EXPORT functions are exported. + Removed the deprecated png_check_sig() function/macro. + Removed recently removed function names from scripts/*.def + Revised pngtest.png to put chunks in the same order written by pngtest + (evidently the same change made in libpng-1.0beta54 was lost). + Added PNG_PRIVATE macro definition in pngconf.h for possible future use. + +version 1.4.0beta97 [November 13, 2009] + Restored pngtest.png to the libpng-1.4.0beta7 version. + Removed projects/beos and netware.txt; no one seems to be supporting them. + Revised Makefile.in + +version 1.4.0beta98 [November 13, 2009] + Added the "xcode" project to zip distributions, + Fixed a typo in scripts/pngwin.def introduced in beta97. + +version 1.4.0beta99 [November 14, 2009] + Moved libpng-config.in and libpng.pc-configure.in out of the scripts + directory, to libpng-config.in and libpng-pc.in, respectively, and + modified Makefile.am and configure.ac accordingly. Now "configure" + needs nothing from the "scripts" directory. + Avoid redefining PNG_CONST in pngconf.h + +version 1.4.0beta100 [November 14, 2009] + Removed ASM builds from projects/visualc6 and projects/visualc71 + Removed scripts/makefile.nommx and makefile.vcawin32 + Revised CMakeLists.txt to account for new location of libpng-config.in + and libpng-pc.in + Updated INSTALL to reflect removal and relocation of files. + +version 1.4.0beta101 [November 14, 2009] + Restored the binary files (*.jpg, *.png, some project files) that were + accidentally deleted from the zip and 7z distributions when the xcode + project was added. + +version 1.4.0beta102 [November 18, 2009] + Added libpng-config.in and libpng-pc.in to the zip and 7z distributions. + Fixed a typo in projects/visualc6/pngtest.dsp, introduced in beta100. + Moved descriptions of makefiles and other scripts out of INSTALL into + scripts/README.txt + Updated the copyright year in scripts/pngwin.rc from 2006 to 2009. + +version 1.4.0beta103 [November 21, 2009] + Removed obsolete comments about ASM from projects/visualc71/README_zlib.txt + Align row_buf on 16-byte boundary in memory. + Restored the PNG_WRITE_FLUSH_AFTER_IEND_SUPPORTED guard around the call + to png_flush() after png_write_IEND(). See 1.4.0beta32, 1.4.0beta50 + changes above and 1.2.30, 1.2.30rc01 and rc03 in 1.2.41 CHANGES. Someone + needs this feature. + Make the 'png_jmpbuf' macro expand to a call that records the correct + longjmp function as well as returning a pointer to the setjmp + jmp_buf buffer, and marked direct access to jmpbuf 'deprecated'. + (John Bowler) + +version 1.4.0beta104 [November 22, 2009] + Removed png_longjmp_ptr from scripts/*.def and libpng.3 + Rebuilt configure scripts with autoconf-2.65 + +version 1.4.0beta105 [November 25, 2009] + Use fast integer PNG_DIVIDE_BY_255() or PNG_DIVIDE_BY_65535() + to accomplish alpha premultiplication when + PNG_READ_COMPOSITE_NODIV_SUPPORTED is defined. + Changed "/255" to "/255.0" in background calculations to make it clear + that the 255 is used as a double. + +version 1.4.0beta106 [November 27, 2009] + Removed premultiplied alpha feature. + +version 1.4.0beta107 [December 4, 2009] + Updated README + Added "#define PNG_NO_PEDANTIC_WARNINGS" in the libpng source files. + Removed "-DPNG_CONFIGURE_LIBPNG" from the makefiles and projects. + Revised scripts/makefile.netbsd, makefile.openbsd, and makefile.sco + to put png.h and pngconf.h in $prefix/include, like the other scripts, + instead of in $prefix/include/libpng. Also revised makefile.sco + to put them in $prefix/include/libpng14 instead of in + $prefix/include/libpng/libpng14. + +version 1.4.0beta108 [December 11, 2009] + Removed leftover "-DPNG_CONFIGURE_LIBPNG" from contrib/pngminim/*/makefile + Relocated png_do_chop() to its original position in pngrtran.c; the + change in version 1.2.41beta08 caused transparency to be handled wrong + in some 16-bit datastreams (Yusaku Sugai). + +version 1.4.0beta109 [December 13, 2009] + Added "bit_depth" parameter to the private png_build_gamma_table() function. + Pass bit_depth=8 to png_build_gamma_table() when bit_depth is 16 but the + PNG_16_TO_8 transform has been set, to avoid unnecessary build of 16-bit + tables. + +version 1.4.0rc02 [December 20, 2009] + Declared png_cleanup_needed "volatile" in pngread.c and pngwrite.c + +version 1.4.0rc03 [December 22, 2009] + Renamed libpng-pc.in back to libpng.pc.in and revised CMakeLists.txt + (revising the change in 1.4.0beta99) + +version 1.4.0rc04 [December 25, 2009] + Swapped PNG_UNKNOWN_CHUNKS_SUPPORTED and PNG_HANDLE_AS_UNKNOWN_SUPPORTED + in pngset.c to be consistent with other changes in version 1.2.38. + +version 1.4.0rc05 [December 25, 2009] + Changed "libpng-pc.in" to "libpng.pc.in" in configure.ac, configure, and + Makefile.in to be consistent with changes in libpng-1.4.0rc03 + +version 1.4.0rc06 [December 29, 2009] + Reverted the gamma_table changes from libpng-1.4.0beta109. + Fixed some indentation errors. + +version 1.4.0rc07 [January 1, 2010] + Revised libpng*.txt and libpng.3 about 1.2.x->1.4.x differences. + Use png_calloc() instead of png_malloc(); png_memset() in pngrutil.c + Update copyright year to 2010. + +version 1.4.0rc08 [January 2, 2010] + Avoid deprecated references to png_ptr-io_ptr and png_ptr->error_ptr + in pngtest.c + +version 1.4.0 [January 3, 2010] + No changes. + +version 1.4.1beta01 [January 8, 2010] + Updated CMakeLists.txt for consistent indentation and to avoid an + unclosed if-statement warning (Philip Lowman). + Revised Makefile.am and Makefile.in to remove references to Y2KINFO, + KNOWNBUG, and libpng.la (Robert Schwebel). + Revised the makefiles to install the same files and symbolic + links as configure, except for libpng.la and libpng14.la. + Make png_set|get_compression_buffer_size() available even when + PNG_WRITE_SUPPORTED is not enabled. + Revised Makefile.am and Makefile.in to simplify their maintenance. + Revised scripts/makefile.linux to install a link to libpng14.so.14.1 + +version 1.4.1beta02 [January 9, 2010] + Revised the rest of the makefiles to install a link to libpng14.so.14.1 + +version 1.4.1beta03 [January 10, 2010] + Removed png_set_premultiply_alpha() from scripts/*.def + +version 1.4.1rc01 [January 16, 2010] + No changes. + +version 1.4.1beta04 [January 23, 2010] + Revised png_decompress_chunk() to improve speed and memory usage when + decoding large chunks. + Added png_set|get_chunk_malloc_max() functions. + +version 1.4.1beta05 [January 26, 2010] + Relocated "int k" declaration in pngtest.c to minimize its scope. + +version 1.4.1beta06 [January 28, 2010] + Revised png_decompress_chunk() to use a two-pass method suggested by + John Bowler. + +version 1.4.1beta07 [February 6, 2010] + Folded some long lines in the source files. + Added defineable PNG_USER_CHUNK_CACHE_MAX, PNG_USER_CHUNK_MALLOC_MAX, + and a PNG_USER_LIMITS_SUPPORTED flag. + Eliminated use of png_ptr->irowbytes and reused the slot in png_ptr as + png_ptr->png_user_chunk_malloc_max. + Revised png_push_save_buffer() to do fewer but larger png_malloc() calls. + +version 1.4.1beta08 [February 6, 2010] + Minor cleanup and updating of dates and copyright year. + +version 1.4.1beta09 [February 7, 2010] + Reverted to original png_push_save_buffer() code. + +version 1.4.1beta10 [February 9, 2010] + Return allocated "old_buffer" in png_push_save_buffer() before calling + png_error(), to avoid a potential memory leak. + +version 1.4.1beta11 [February 12, 2010] + Relocated misplaced closing curley bracket in png_decompress_chunk(). + Removed unused "buffer_size" variable from png_decompress_chunk(). + Removed the cbuilder5 project, which has not been updated to 1.4.0. + Complete rewrite of two-pass png_decompress_chunk() by John Bowler. + +version 1.4.1beta12 [February 14, 2010] + Fixed type declaration of png_get_user_malloc_max() in pngget.c (Daisuke + Nishikawa) + +version 1.4.1rc02 [January 18, 2010] + No changes. + +version 1.4.1rc03 [February 19, 2010] + Noted in scripts/makefile.mingw that it expects to be run under MSYS. + Removed obsolete unused MMX-querying support from contrib/gregbook + Removed the AIX redefinition of jmpbuf in png.h + Define _ALL_SOURCE in configure.ac, makefile.aix, and CMakeLists.txt + when using AIX compiler. + +version 1.4.1rc04 [February 19, 2010] + Removed unused gzio.c from contrib/pngminim gather and makefile scripts + +version 1.4.1 [February 25, 2010] + +version 1.4.2beta01 [April 1, 2010] + Conditionally compile an "else" statement in png_decompress_chunk(). + Restored the macro definition of png_check_sig(). + +version 1.4.2rc01 [April 10, 2010] + No changes. + +version 1.4.2rc02 [April 16, 2010] + Documented the fact that png_set_dither() was disabled since libpng-1.4.0. + Reenabled png_set_dither() but renamed it to png_set_quantize() to reflect + more accurately what it actually does. At the same time, renamed + the PNG_DITHER_[RED,GREEN_BLUE]_BITS macros to + PNG_QUANTIZE_[RED,GREEN,BLUE]_BITS. + +version 1.4.2rc03 [April 24, 2010] + Added some "(long)" typecasts to printf calls in png_handle_cHRM(). + Relaxed the overly-restrictive permissions of some files. + +version 1.4.2rc04 [April 28, 2010] + Added the "vstudio" project to replace "visualc6" and "visualc71" which + will be removed from libpng-1.5.0. + Demonstrate in example.c that lang_key should be initialized. + Set PNG_NO_READ_BGR, PNG_NO_IO_STATE, and PNG_NO_TIME_RFC1123 in + contrib/pngminim/decoder/pngusr.h to make a smaller decoder application. + +version 1.4.2rc05 [April 29, 2010] + Include png_reset_zstream() in png.c only when PNG_READ_SUPPORTED is defined. + Removed dummy_inflate.c and uncompr.c from contrib/pngminim/encoder + Corrected PNG_UNKNOWN_CHUNKS_SUPPORTED to PNG_HANDLE_AS_UNKNOWN_SUPPORTED + in gregbook/readpng2.c + Corrected protection of png_get_user_transform_ptr. The API declaration in + png.h is removed if both READ and WRITE USER_TRANSFORM are turned off + but was left defined in pngtrans.c + +version 1.4.2rc06 [May 3, 2010] + Moved declarations of umsg[] inside the proper #ifdef blocks in pngrutil.c + +version 1.4.2 [May 6, 2010] + +version 1.4.3beta01 [June 18, 2010] + Added missing quotation marks in the aix block of configure.ac + The new "vstudio" project was missing from the zip and 7z distributions. + In pngpread.c: png_push_have_row() add check for new_row > height + +version 1.4.3beta02 [June 18, 2010] + Removed the now-redundant check for out-of-bounds new_row from example.c + +version 1.4.3beta03 [June 18, 2010] + In pngpread.c: png_push_finish_row() add check for too many rows. + +version 1.4.3beta04 [June 19, 2010] + In pngpread.c: png_push_process_row() add check for too many rows. + Removed the checks added in beta01 and beta03, as they are now redundant. + +version 1.4.3beta05 [June 20, 2010] + Rewrote png_process_IDAT_data to consistently treat extra data as warnings + and handle end conditions more cleanly. + Removed the new (beta04) check in png_push_process_row(). + +version 1.4.3rc01 [June 21, 2010] + Revised some comments in png_process_IDAT_data(). + +version 1.4.3rc02 [June 22, 2010] + Changed char *msg to PNG_CONST char *msg in pngrutil.c + Stop memory leak when reading a malformed sCAL chunk. + Removed some trailing blanks. + +version 1.4.3rc03 [June 23, 2010] + Revised pngpread.c patch of beta05 to avoid an endless loop. + +version 1.4.3 [June 26, 2010] + Updated some of the "last changed" dates. + +version 1.4.4beta01 [July 12, 2010] + Removed extraneous new_push_process_row.c file. + Revised the "SEE ALSO" style of libpng.3, libpngpf.3, and png.5 + Removed some newly-added TAB characters from pngpread.c. + Fixed some indentation in pngpread.c and pngrutil.c + Changed "extern PNG_EXPORT" to "PNG_EXPORT" in png.h (Jan Nijtmans) + Changed "extern" to "PNG_EXTERN" in pngpriv.h (except for the 'extern "C" {') + Put "#ifndef PNG_EXTERN, #endif" around "#define PNG_EXTERN" in pngpriv.h + +version 1.4.4beta02 [July 24, 2010] + Added -DNO_PNG_SNPRINTF to CFLAGS in scripts/makefile.dj2 + Moved the definition of png_snprintf() outside of the enclosing + #ifdef blocks in pngconf.h + Added a special case typedef of png_longjmp_ptr for WATCOM. + +version 1.4.4beta03 [July 24, 2010] + Removed reference to cbuilder5/* from Makefile.in and Makefile.am + Eliminated the new special case typedef of png_longjmp_ptr for WATCOM + and made a special case "#define PNGAPI" in pngconf.h instead. + +version 1.4.4beta04 [July 31, 2010] + Updated the read macros and functions from 1.5.0beta38. + +version 1.4.4beta05 [August 6, 2010] + Updated projects/visualc71 so it can find scripts/pnglibconf.h + Removed unused png_mem_* defines from pngconf.h. + Correct use of _WINDOWS_ in pngconf.h + +version 1.4.4beta06 [August 11, 2010] + Don't try to use version-script with cygwin/mingw. + Revised contrib/gregbook to work under cygwin/mingw. + +version 1.4.4beta07 [August 26, 2010] + Updated prebuilt aclocal.m4 and ltmain.sh + Add .dll.a to the list of extensions to be symlinked by Makefile.am (Yaakov) + Updated CMakeLists.txt to use CMAKE_INSTALL_LIBDIR variable; useful for + installing libpng in /usr/lib64 (Funda Wang). + Revised CMakeLists.txt to put the man pages in share/man/man* not man/man* + Revised CMakeLists.txt to make symlinks instead of copies when installing. + Changed PNG_LIB_NAME from pngNN to libpngNN in CMakeLists.txt (Philip Lowman) + Moved "#include pngusr.h" ahead of PNG_USER_PRIVATEBUILD test in pngconf.h + Eliminated a deprecated reference to png_ptr->io_ptr in pngtest.c + Eliminated new unnecessary #if tests regarding the sCAL chunk from pngrutil.c + +version 1.4.4beta08 [September 2, 2010] + Updated the xcode project to work with libpng-1.4.x and added iOS targets + for simulator and device (Philippe Hausler). + +version 1.4.4rc01 [September 10, 2010] + No changes. + +version 1.4.4rc02 [September 13, 2010] + Revised CMakeLists.txt (Philip Lowman). + +version 1.4.4rc03 [September 14, 2010] + Removed an extraneous close-double-quote from CMakeLists.txt + Eliminated another deprecated reference to png_ptr->io_ptr in pngtest.c + +version 1.4.4rc04 [September 16, 2010] + Fixed indentation and removed debugging message from CMakeLists.txt + Revised autogen.sh to recognize and use $AUTOCONF, $AUTOMAKE, $AUTOHEADER, + $AUTOPOINT, $ACLOCAL and $LIBTOOLIZE + +version 1.4.4rc05 [September 20, 2010] + Rebuilt configure scripts with automake-1.11.1 instead of automake-1.11. + Removed unused mkinstalldirs file. + +version 1.4.4 [September 23, 2010] + No changes. + +Send comments/corrections/commendations to glennrp at users.sourceforge.net +or to png-mng-implement at lists.sf.net (subscription required; visit +https://lists.sourceforge.net/lists/listinfo/png-mng-implement). + +Glenn R-P +*/ } +#endif diff --git a/libpng/LICENSE b/libpng/LICENSE new file mode 100644 index 0000000..756ebd0 --- /dev/null +++ b/libpng/LICENSE @@ -0,0 +1,111 @@ + +This copy of the libpng notices is provided for your convenience. In case of +any discrepancy between this copy and the notices in the file png.h that is +included in the libpng distribution, the latter shall prevail. + +COPYRIGHT NOTICE, DISCLAIMER, and LICENSE: + +If you modify libpng you may insert additional notices immediately following +this sentence. + +This code is released under the libpng license. + +libpng versions 1.2.6, August 15, 2004, through 1.4.4, September 23, 2010, are +Copyright (c) 2004, 2006-2010 Glenn Randers-Pehrson, and are +distributed according to the same disclaimer and license as libpng-1.2.5 +with the following individual added to the list of Contributing Authors + + Cosmin Truta + +libpng versions 1.0.7, July 1, 2000, through 1.2.5 - October 3, 2002, are +Copyright (c) 2000-2002 Glenn Randers-Pehrson, and are +distributed according to the same disclaimer and license as libpng-1.0.6 +with the following individuals added to the list of Contributing Authors + + Simon-Pierre Cadieux + Eric S. Raymond + Gilles Vollant + +and with the following additions to the disclaimer: + + There is no warranty against interference with your enjoyment of the + library or against infringement. There is no warranty that our + efforts or the library will fulfill any of your particular purposes + or needs. This library is provided with all faults, and the entire + risk of satisfactory quality, performance, accuracy, and effort is with + the user. + +libpng versions 0.97, January 1998, through 1.0.6, March 20, 2000, are +Copyright (c) 1998, 1999 Glenn Randers-Pehrson, and are +distributed according to the same disclaimer and license as libpng-0.96, +with the following individuals added to the list of Contributing Authors: + + Tom Lane + Glenn Randers-Pehrson + Willem van Schaik + +libpng versions 0.89, June 1996, through 0.96, May 1997, are +Copyright (c) 1996, 1997 Andreas Dilger +Distributed according to the same disclaimer and license as libpng-0.88, +with the following individuals added to the list of Contributing Authors: + + John Bowler + Kevin Bracey + Sam Bushell + Magnus Holmgren + Greg Roelofs + Tom Tanner + +libpng versions 0.5, May 1995, through 0.88, January 1996, are +Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc. + +For the purposes of this copyright and license, "Contributing Authors" +is defined as the following set of individuals: + + Andreas Dilger + Dave Martindale + Guy Eric Schalnat + Paul Schmidt + Tim Wegner + +The PNG Reference Library is supplied "AS IS". The Contributing Authors +and Group 42, Inc. disclaim all warranties, expressed or implied, +including, without limitation, the warranties of merchantability and of +fitness for any purpose. The Contributing Authors and Group 42, Inc. +assume no liability for direct, indirect, incidental, special, exemplary, +or consequential damages, which may result from the use of the PNG +Reference Library, even if advised of the possibility of such damage. + +Permission is hereby granted to use, copy, modify, and distribute this +source code, or portions hereof, for any purpose, without fee, subject +to the following restrictions: + +1. The origin of this source code must not be misrepresented. + +2. Altered versions must be plainly marked as such and must not + be misrepresented as being the original source. + +3. This Copyright notice may not be removed or altered from any + source or altered source distribution. + +The Contributing Authors and Group 42, Inc. specifically permit, without +fee, and encourage the use of this source code as a component to +supporting the PNG file format in commercial products. If you use this +source code in a product, acknowledgment is not required but would be +appreciated. + + +A "png_get_copyright" function is available, for convenient use in "about" +boxes and the like: + + printf("%s",png_get_copyright(NULL)); + +Also, the PNG logo (in PNG format, of course) is supplied in the +files "pngbar.png" and "pngbar.jpg (88x31) and "pngnow.png" (98x31). + +Libpng is OSI Certified Open Source Software. OSI Certified Open Source is a +certification mark of the Open Source Initiative. + +Glenn Randers-Pehrson +glennrp at users.sourceforge.net +September 23, 2010 diff --git a/libpng/README b/libpng/README new file mode 100644 index 0000000..255378b --- /dev/null +++ b/libpng/README @@ -0,0 +1,257 @@ +README for libpng version 1.4.4 - September 23, 2010 (shared library 14.0) +See the note about version numbers near the top of png.h + +See INSTALL for instructions on how to install libpng. + +Libpng comes in several distribution formats. Get libpng-*.tar.gz, +libpng-*.tar.xz or libpng-*.tar.bz2 if you want UNIX-style line endings +in the text files, or lpng*.zip if you want DOS-style line endings. + +Version 0.89 was the first official release of libpng. Don't let the +fact that it's the first release fool you. The libpng library has been in +extensive use and testing since mid-1995. By late 1997 it had +finally gotten to the stage where there hadn't been significant +changes to the API in some time, and people have a bad feeling about +libraries with versions < 1.0. Version 1.0.0 was released in +March 1998. + +**** +Note that some of the changes to the png_info structure render this +version of the library binary incompatible with libpng-0.89 or +earlier versions if you are using a shared library. The type of the +"filler" parameter for png_set_filler() has changed from png_byte to +png_uint_32, which will affect shared-library applications that use +this function. + +To avoid problems with changes to the internals of png_info_struct, +new APIs have been made available in 0.95 to avoid direct application +access to info_ptr. These functions are the png_set_ and +png_get_ functions. These functions should be used when +accessing/storing the info_struct data, rather than manipulating it +directly, to avoid such problems in the future. + +It is important to note that the APIs do not make current programs +that access the info struct directly incompatible with the new +library. However, it is strongly suggested that new programs use +the new APIs (as shown in example.c and pngtest.c), and older programs +be converted to the new format, to facilitate upgrades in the future. +**** + +Additions since 0.90 include the ability to compile libpng as a +Windows DLL, and new APIs for accessing data in the info struct. +Experimental functions include the ability to set weighting and cost +factors for row filter selection, direct reads of integers from buffers +on big-endian processors that support misaligned data access, faster +methods of doing alpha composition, and more accurate 16->8 bit color +conversion. + +The additions since 0.89 include the ability to read from a PNG stream +which has had some (or all) of the signature bytes read by the calling +application. This also allows the reading of embedded PNG streams that +do not have the PNG file signature. As well, it is now possible to set +the library action on the detection of chunk CRC errors. It is possible +to set different actions based on whether the CRC error occurred in a +critical or an ancillary chunk. + +The changes made to the library, and bugs fixed are based on discussions +on the PNG-implement mailing list and not on material submitted +privately to Guy, Andreas, or Glenn. They will forward any good +suggestions to the list. + +For a detailed description on using libpng, read libpng.txt. For +examples of libpng in a program, see example.c and pngtest.c. For usage +information and restrictions (what little they are) on libpng, see +png.h. For a description on using zlib (the compression library used by +libpng) and zlib's restrictions, see zlib.h + +I have included a general makefile, as well as several machine and +compiler specific ones, but you may have to modify one for your own needs. + +You should use zlib 1.0.4 or later to run this, but it MAY work with +versions as old as zlib 0.95. Even so, there are bugs in older zlib +versions which can cause the output of invalid compression streams for +some images. You will definitely need zlib 1.0.4 or later if you are +taking advantage of the MS-DOS "far" structure allocation for the small +and medium memory models. You should also note that zlib is a +compression library that is useful for more things than just PNG files. +You can use zlib as a drop-in replacement for fread() and fwrite() if +you are so inclined. + +zlib should be available at the same place that libpng is, or at. +ftp://ftp.info-zip.org/pub/infozip/zlib + +You may also want a copy of the PNG specification. It is available +as an RFC, a W3C Recommendation, and an ISO/IEC Standard. You can find +these at http://www.libpng.org/pub/png/documents/ + +This code is currently being archived at libpng.sf.net in the +[DOWNLOAD] area, and on CompuServe, Lib 20 (PNG SUPPORT) +at GO GRAPHSUP. If you can't find it in any of those places, +e-mail me, and I'll help you find it. + +If you have any code changes, requests, problems, etc., please e-mail +them to me. Also, I'd appreciate any make files or project files, +and any modifications you needed to make to get libpng to compile, +along with a #define variable to tell what compiler/system you are on. +If you needed to add transformations to libpng, or wish libpng would +provide the image in a different way, drop me a note (and code, if +possible), so I can consider supporting the transformation. +Finally, if you get any warning messages when compiling libpng +(note: not zlib), and they are easy to fix, I'd appreciate the +fix. Please mention "libpng" somewhere in the subject line. Thanks. + +This release was created and will be supported by myself (of course +based in a large way on Guy's and Andreas' earlier work), and the PNG +development group. + +Send comments/corrections/commendations to png-mng-implement at +lists.sourceforge.net (subscription required; visit +https://lists.sourceforge.net/lists/listinfo/png-mng-implement +to subscribe) or to glennrp at users.sourceforge.net + +You can't reach Guy, the original libpng author, at the addresses +given in previous versions of this document. He and Andreas will +read mail addressed to the png-implement list, however. + +Please do not send general questions about PNG. Send them to +the (png-list at ccrc.wustl.edu, subscription required, write to +majordomo at ccrc.wustl.edu with "subscribe png-list" in your message). +On the other hand, +please do not send libpng questions to that address, send them to me +or to the png-implement list. I'll +get them in the end anyway. If you have a question about something +in the PNG specification that is related to using libpng, send it +to me. Send me any questions that start with "I was using libpng, +and ...". If in doubt, send questions to me. I'll bounce them +to others, if necessary. + +Please do not send suggestions on how to change PNG. We have +been discussing PNG for nine years now, and it is official and +finished. If you have suggestions for libpng, however, I'll +gladly listen. Even if your suggestion is not used immediately, +it may be used later. + +Files in this distribution: + + ANNOUNCE => Announcement of this version, with recent changes + CHANGES => Description of changes between libpng versions + KNOWNBUG => List of known bugs and deficiencies + LICENSE => License to use and redistribute libpng + README => This file + TODO => Things not implemented in the current library + Y2KINFO => Statement of Y2K compliance + example.c => Example code for using libpng functions + libpng.3 => manual page for libpng (includes libpng.txt) + libpng.txt => Description of libpng and its functions + libpngpf.3 => manual page for libpng's private functions + png.5 => manual page for the PNG format + png.c => Basic interface functions common to library + png.h => Library function and interface declarations + pngconf.h => System specific library configuration + pngerror.c => Error/warning message I/O functions + pngget.c => Functions for retrieving info from struct + pngmem.c => Memory handling functions + pngbar.png => PNG logo, 88x31 + pngnow.png => PNG logo, 98x31 + pngpread.c => Progressive reading functions + pngread.c => Read data/helper high-level functions + pngrio.c => Lowest-level data read I/O functions + pngrtran.c => Read data transformation functions + pngrutil.c => Read data utility functions + pngset.c => Functions for storing data into the info_struct + pngtest.c => Library test program + pngtest.png => Library test sample image + pngtrans.c => Common data transformation functions + pngwio.c => Lowest-level write I/O functions + pngwrite.c => High-level write functions + pngwtran.c => Write data transformations + pngwutil.c => Write utility functions + contrib => Contributions + gregbook => source code for PNG reading and writing, from + Greg Roelofs' "PNG: The Definitive Guide", + O'Reilly, 1999 + msvctest => Builds and runs pngtest using a MSVC workspace + pngminus => Simple pnm2png and png2pnm programs + pngsuite => Test images + visupng => Contains a MSVC workspace for VisualPng + projects => Contains project files and workspaces for + building a DLL + c5builder => Contains a Borland workspace for building + libpng and zlib + visualc6 => Contains a Microsoft Visual C++ (MSVC) + workspace for building libpng and zlib + scripts => Directory containing scripts for building libpng: + descrip.mms => VMS makefile for MMS or MMK + makefile.std => Generic UNIX makefile (cc, creates static + libpng.a) + makefile.elf => Linux/ELF makefile symbol versioning, + (gcc, creates libpng14.so.14.1.4.4) + makefile.linux => Linux/ELF makefile + (gcc, creates libpng14.so.14.1.4.4) + makefile.gcc => Generic makefile (gcc, creates static libpng.a) + makefile.knr => Archaic UNIX Makefile that converts files with + ansi2knr (Requires ansi2knr.c from + ftp://ftp.cs.wisc.edu/ghost) + makefile.aix => AIX makefile + makefile.cygwin => Cygwin/gcc makefile + makefile.darwin => Darwin makefile + makefile.dec => DEC Alpha UNIX makefile + makefile.freebsd => FreeBSD makefile + makefile.hpgcc => HPUX makefile using gcc + makefile.hpux => HPUX (10.20 and 11.00) makefile + makefile.hp64 => HPUX (10.20 and 11.00) makefile, 64 bit + makefile.ibmc => IBM C/C++ version 3.x for Win32 and OS/2 (static) + makefile.intel => Intel C/C++ version 4.0 and later + makefile.mingw => Mingw/gcc makefile + makefile.netbsd => NetBSD/cc makefile, makes libpng.so. + makefile.ne14bsd => NetBSD/cc makefile, makes + libpng14.so + makefile.openbsd => OpenBSD makefile + makefile.sgi => Silicon Graphics IRIX (cc, creates static lib) + makefile.sggcc => Silicon Graphics + (gcc, creates libpng14.so.14.1.4.4) + makefile.sunos => Sun makefile + makefile.solaris => Solaris 2.X makefile + (gcc, creates libpng14.so.14.1.4.4) + makefile.so9 => Solaris 9 makefile + (gcc, creates libpng14.so.14.1.4.4) + makefile.32sunu => Sun Ultra 32-bit makefile + makefile.64sunu => Sun Ultra 64-bit makefile + makefile.sco => For SCO OSr5 ELF and Unixware 7 with Native cc + makefile.mips => MIPS makefile + makefile.acorn => Acorn makefile + makefile.amiga => Amiga makefile + smakefile.ppc => AMIGA smakefile for SAS C V6.58/7.00 PPC + compiler (Requires SCOPTIONS, copied from + scripts/SCOPTIONS.ppc) + makefile.atari => Atari makefile + makefile.beos => BEOS makefile for X86 + makefile.bor => Borland makefile (uses bcc) + makefile.bc32 => 32-bit Borland C++ (all modules compiled in C mode) + makefile.tc3 => Turbo C 3.0 makefile + makefile.dj2 => DJGPP 2 makefile + makefile.msc => Microsoft C makefile + makefile.vcwin32 => makefile for Microsoft Visual C++ 4.0 and + later (does not use assembler code) + makefile.os2 => OS/2 Makefile (gcc and emx, requires pngos2.def) + png32ce.def => module definition for makefile.cegccg + pngos2.def => OS/2 module definition file used by + makefile.os2 + pngwin.def => module definition file used by + makefile.cygwin and makefile.mingw + makefile.watcom => Watcom 10a+ Makefile, 32-bit flat memory model + makevms.com => VMS build script + SCOPTIONS.ppc => Used with smakefile.ppc + +Good luck, and happy coding. + +-Glenn Randers-Pehrson (current maintainer, since 1998) + Internet: glennrp at users.sourceforge.net + +-Andreas Eric Dilger (former maintainer, 1996-1997) + Internet: adilger at enel.ucalgary.ca + Web: http://www-mddsp.enel.ucalgary.ca/People/adilger/ + +-Guy Eric Schalnat (original author and former maintainer, 1995-1996) + (formerly of Group 42, Inc) + Internet: gschal at infinet.com diff --git a/libpng/TODO b/libpng/TODO new file mode 100644 index 0000000..0af8d82 --- /dev/null +++ b/libpng/TODO @@ -0,0 +1,31 @@ +/* +TODO - list of things to do for libpng: + +Final bug fixes. +Improve API by hiding the png_struct and png_info structs. +Finish work on the no-floating-point version (including gamma compensation) +Better C++ wrapper/full C++ implementation? +Fix problem with C++ and EXTERN "C". +cHRM transformation. +Improve setjmp/longjmp usage or remove it in favor of returning error codes. +Add "grayscale->palette" transformation and "palette->grayscale" detection. +Improved quantizing and dithering. +Multi-lingual error and warning message support. +Complete sRGB transformation (presently it simply uses gamma=0.45455). +Man pages for function calls. +Better documentation. +Better filter selection + (counting huffman bits/precompression? filter inertia? filter costs?). +Histogram creation. +Text conversion between different code pages (Latin-1 -> Mac and DOS). +Build gamma tables using fixed point (and do away with floating point entirely). +Avoid building gamma tables whenever possible. +Use greater precision when changing to linear gamma for compositing against + background and doing rgb-to-gray transformation. +Investigate pre-incremented loop counters and other loop constructions. +Add interpolated method of handling interlacing. +Provide for conditional compilation of 16-bit support (except for the + initial stripping down to 8-bits when reading a 16-bit PNG datastream). +Switch to the simpler zlib (zlib/libpng) license if legally possible. + +*/ diff --git a/libpng/libpng.txt b/libpng/libpng.txt new file mode 100644 index 0000000..dbd7e3b --- /dev/null +++ b/libpng/libpng.txt @@ -0,0 +1,3352 @@ +libpng.txt - A description on how to use and modify libpng + + libpng version 1.4.4 - September 23, 2010 + Updated and distributed by Glenn Randers-Pehrson + + Copyright (c) 1998-2010 Glenn Randers-Pehrson + + This document is released under the libpng license. + For conditions of distribution and use, see the disclaimer + and license in png.h + + Based on: + + libpng versions 0.97, January 1998, through 1.4.4 - September 23, 2010 + Updated and distributed by Glenn Randers-Pehrson + Copyright (c) 1998-2010 Glenn Randers-Pehrson + + libpng 1.0 beta 6 version 0.96 May 28, 1997 + Updated and distributed by Andreas Dilger + Copyright (c) 1996, 1997 Andreas Dilger + + libpng 1.0 beta 2 - version 0.88 January 26, 1996 + For conditions of distribution and use, see copyright + notice in png.h. Copyright (c) 1995, 1996 Guy Eric + Schalnat, Group 42, Inc. + + Updated/rewritten per request in the libpng FAQ + Copyright (c) 1995, 1996 Frank J. T. Wojcik + December 18, 1995 & January 20, 1996 + +I. Introduction + +This file describes how to use and modify the PNG reference library +(known as libpng) for your own use. There are five sections to this +file: introduction, structures, reading, writing, and modification and +configuration notes for various special platforms. In addition to this +file, example.c is a good starting point for using the library, as +it is heavily commented and should include everything most people +will need. We assume that libpng is already installed; see the +INSTALL file for instructions on how to install libpng. + +For examples of libpng usage, see the files "example.c", "pngtest.c", +and the files in the "contrib" directory, all of which are included in +the libpng distribution. + +Libpng was written as a companion to the PNG specification, as a way +of reducing the amount of time and effort it takes to support the PNG +file format in application programs. + +The PNG specification (second edition), November 2003, is available as +a W3C Recommendation and as an ISO Standard (ISO/IEC 15948:2003 (E)) at +. It is technically equivalent +to the PNG specification (second edition) but has some additional material. + +The PNG-1.0 specification is available +as RFC 2083 and as a +W3C Recommendation . + +Some additional chunks are described in the special-purpose public chunks +documents at . + +Other information +about PNG, and the latest version of libpng, can be found at the PNG home +page, . + +Most users will not have to modify the library significantly; advanced +users may want to modify it more. All attempts were made to make it as +complete as possible, while keeping the code easy to understand. +Currently, this library only supports C. Support for other languages +is being considered. + +Libpng has been designed to handle multiple sessions at one time, +to be easily modifiable, to be portable to the vast majority of +machines (ANSI, K&R, 16-, 32-, and 64-bit) available, and to be easy +to use. The ultimate goal of libpng is to promote the acceptance of +the PNG file format in whatever way possible. While there is still +work to be done (see the TODO file), libpng should cover the +majority of the needs of its users. + +Libpng uses zlib for its compression and decompression of PNG files. +Further information about zlib, and the latest version of zlib, can +be found at the zlib home page, . +The zlib compression utility is a general purpose utility that is +useful for more than PNG files, and can be used without libpng. +See the documentation delivered with zlib for more details. +You can usually find the source files for the zlib utility wherever you +find the libpng source files. + +Libpng is thread safe, provided the threads are using different +instances of the structures. Each thread should have its own +png_struct and png_info instances, and thus its own image. +Libpng does not protect itself against two threads using the +same instance of a structure. + +II. Structures + +There are two main structures that are important to libpng, png_struct +and png_info. The first, png_struct, is an internal structure that +will not, for the most part, be used by a user except as the first +variable passed to every libpng function call. + +The png_info structure is designed to provide information about the +PNG file. At one time, the fields of png_info were intended to be +directly accessible to the user. However, this tended to cause problems +with applications using dynamically loaded libraries, and as a result +a set of interface functions for png_info (the png_get_*() and png_set_*() +functions) was developed. The fields of png_info are still available for +older applications, but it is suggested that applications use the new +interfaces if at all possible. + +Applications that do make direct access to the members of png_struct (except +for png_ptr->jmpbuf) must be recompiled whenever the library is updated, +and applications that make direct access to the members of png_info must +be recompiled if they were compiled or loaded with libpng version 1.0.6, +in which the members were in a different order. In version 1.0.7, the +members of the png_info structure reverted to the old order, as they were +in versions 0.97c through 1.0.5. Starting with version 2.0.0, both +structures are going to be hidden, and the contents of the structures will +only be accessible through the png_get/png_set functions. + +The png.h header file is an invaluable reference for programming with libpng. +And while I'm on the topic, make sure you include the libpng header file: + +#include + +III. Reading + +We'll now walk you through the possible functions to call when reading +in a PNG file sequentially, briefly explaining the syntax and purpose +of each one. See example.c and png.h for more detail. While +progressive reading is covered in the next section, you will still +need some of the functions discussed in this section to read a PNG +file. + +Setup + +You will want to do the I/O initialization(*) before you get into libpng, +so if it doesn't work, you don't have much to undo. Of course, you +will also want to insure that you are, in fact, dealing with a PNG +file. Libpng provides a simple check to see if a file is a PNG file. +To use it, pass in the first 1 to 8 bytes of the file to the function +png_sig_cmp(), and it will return 0 (false) if the bytes match the +corresponding bytes of the PNG signature, or nonzero (true) otherwise. +Of course, the more bytes you pass in, the greater the accuracy of the +prediction. + +If you are intending to keep the file pointer open for use in libpng, +you must ensure you don't read more than 8 bytes from the beginning +of the file, and you also have to make a call to png_set_sig_bytes_read() +with the number of bytes you read from the beginning. Libpng will +then only check the bytes (if any) that your program didn't read. + +(*): If you are not using the standard I/O functions, you will need +to replace them with custom functions. See the discussion under +Customizing libpng. + + + FILE *fp = fopen(file_name, "rb"); + if (!fp) + { + return (ERROR); + } + fread(header, 1, number, fp); + is_png = !png_sig_cmp(header, 0, number); + if (!is_png) + { + return (NOT_PNG); + } + + +Next, png_struct and png_info need to be allocated and initialized. In +order to ensure that the size of these structures is correct even with a +dynamically linked libpng, there are functions to initialize and +allocate the structures. We also pass the library version, optional +pointers to error handling functions, and a pointer to a data struct for +use by the error functions, if necessary (the pointer and functions can +be NULL if the default error handlers are to be used). See the section +on Changes to Libpng below regarding the old initialization functions. +The structure allocation functions quietly return NULL if they fail to +create the structure, so your application should check for that. + + png_structp png_ptr = png_create_read_struct + (PNG_LIBPNG_VER_STRING, (png_voidp)user_error_ptr, + user_error_fn, user_warning_fn); + if (!png_ptr) + return (ERROR); + + png_infop info_ptr = png_create_info_struct(png_ptr); + if (!info_ptr) + { + png_destroy_read_struct(&png_ptr, + (png_infopp)NULL, (png_infopp)NULL); + return (ERROR); + } + + png_infop end_info = png_create_info_struct(png_ptr); + if (!end_info) + { + png_destroy_read_struct(&png_ptr, &info_ptr, + (png_infopp)NULL); + return (ERROR); + } + +If you want to use your own memory allocation routines, +define PNG_USER_MEM_SUPPORTED and use +png_create_read_struct_2() instead of png_create_read_struct(): + + png_structp png_ptr = png_create_read_struct_2 + (PNG_LIBPNG_VER_STRING, (png_voidp)user_error_ptr, + user_error_fn, user_warning_fn, (png_voidp) + user_mem_ptr, user_malloc_fn, user_free_fn); + +The error handling routines passed to png_create_read_struct() +and the memory alloc/free routines passed to png_create_struct_2() +are only necessary if you are not using the libpng supplied error +handling and memory alloc/free functions. + +When libpng encounters an error, it expects to longjmp back +to your routine. Therefore, you will need to call setjmp and pass +your png_jmpbuf(png_ptr). If you read the file from different +routines, you will need to update the jmpbuf field every time you enter +a new routine that will call a png_*() function. + +See your documentation of setjmp/longjmp for your compiler for more +information on setjmp/longjmp. See the discussion on libpng error +handling in the Customizing Libpng section below for more information +on the libpng error handling. If an error occurs, and libpng longjmp's +back to your setjmp, you will want to call png_destroy_read_struct() to +free any memory. + + if (setjmp(png_jmpbuf(png_ptr))) + { + png_destroy_read_struct(&png_ptr, &info_ptr, + &end_info); + fclose(fp); + return (ERROR); + } + +If you would rather avoid the complexity of setjmp/longjmp issues, +you can compile libpng with PNG_NO_SETJMP, in which case +errors will result in a call to PNG_ABORT() which defaults to abort(). + +You can #define PNG_ABORT() to a function that does something +more useful than abort(), as long as your function does not +return. + +Now you need to set up the input code. The default for libpng is to +use the C function fread(). If you use this, you will need to pass a +valid FILE * in the function png_init_io(). Be sure that the file is +opened in binary mode. If you wish to handle reading data in another +way, you need not call the png_init_io() function, but you must then +implement the libpng I/O methods discussed in the Customizing Libpng +section below. + + png_init_io(png_ptr, fp); + +If you had previously opened the file and read any of the signature from +the beginning in order to see if this was a PNG file, you need to let +libpng know that there are some bytes missing from the start of the file. + + png_set_sig_bytes(png_ptr, number); + +You can change the zlib compression buffer size to be used while +reading compressed data with + + png_set_compression_buffer_size(png_ptr, buffer_size); + +where the default size is 8192 bytes. Note that the buffer size +is changed immediately and the buffer is reallocated immediately, +instead of setting a flag to be acted upon later. + +Setting up callback code + +You can set up a callback function to handle any unknown chunks in the +input stream. You must supply the function + + read_chunk_callback(png_ptr ptr, + png_unknown_chunkp chunk); + { + /* The unknown chunk structure contains your + chunk data, along with similar data for any other + unknown chunks: */ + + png_byte name[5]; + png_byte *data; + png_size_t size; + + /* Note that libpng has already taken care of + the CRC handling */ + + /* put your code here. Search for your chunk in the + unknown chunk structure, process it, and return one + of the following: */ + + return (-n); /* chunk had an error */ + return (0); /* did not recognize */ + return (n); /* success */ + } + +(You can give your function another name that you like instead of +"read_chunk_callback") + +To inform libpng about your function, use + + png_set_read_user_chunk_fn(png_ptr, user_chunk_ptr, + read_chunk_callback); + +This names not only the callback function, but also a user pointer that +you can retrieve with + + png_get_user_chunk_ptr(png_ptr); + +If you call the png_set_read_user_chunk_fn() function, then all unknown +chunks will be saved when read, in case your callback function will need +one or more of them. This behavior can be changed with the +png_set_keep_unknown_chunks() function, described below. + +At this point, you can set up a callback function that will be +called after each row has been read, which you can use to control +a progress meter or the like. It's demonstrated in pngtest.c. +You must supply a function + + void read_row_callback(png_ptr ptr, png_uint_32 row, + int pass); + { + /* put your code here */ + } + +(You can give it another name that you like instead of "read_row_callback") + +To inform libpng about your function, use + + png_set_read_status_fn(png_ptr, read_row_callback); + +Unknown-chunk handling + +Now you get to set the way the library processes unknown chunks in the +input PNG stream. Both known and unknown chunks will be read. Normal +behavior is that known chunks will be parsed into information in +various info_ptr members while unknown chunks will be discarded. This +behavior can be wasteful if your application will never use some known +chunk types. To change this, you can call: + + png_set_keep_unknown_chunks(png_ptr, keep, + chunk_list, num_chunks); + keep - 0: default unknown chunk handling + 1: ignore; do not keep + 2: keep only if safe-to-copy + 3: keep even if unsafe-to-copy + You can use these definitions: + PNG_HANDLE_CHUNK_AS_DEFAULT 0 + PNG_HANDLE_CHUNK_NEVER 1 + PNG_HANDLE_CHUNK_IF_SAFE 2 + PNG_HANDLE_CHUNK_ALWAYS 3 + chunk_list - list of chunks affected (a byte string, + five bytes per chunk, NULL or '\0' if + num_chunks is 0) + num_chunks - number of chunks affected; if 0, all + unknown chunks are affected. If nonzero, + only the chunks in the list are affected + +Unknown chunks declared in this way will be saved as raw data onto a +list of png_unknown_chunk structures. If a chunk that is normally +known to libpng is named in the list, it will be handled as unknown, +according to the "keep" directive. If a chunk is named in successive +instances of png_set_keep_unknown_chunks(), the final instance will +take precedence. The IHDR and IEND chunks should not be named in +chunk_list; if they are, libpng will process them normally anyway. + +Here is an example of the usage of png_set_keep_unknown_chunks(), +where the private "vpAg" chunk will later be processed by a user chunk +callback function: + + png_byte vpAg[5]={118, 112, 65, 103, (png_byte) '\0'}; + + #if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED) + png_byte unused_chunks[]= + { + 104, 73, 83, 84, (png_byte) '\0', /* hIST */ + 105, 84, 88, 116, (png_byte) '\0', /* iTXt */ + 112, 67, 65, 76, (png_byte) '\0', /* pCAL */ + 115, 67, 65, 76, (png_byte) '\0', /* sCAL */ + 115, 80, 76, 84, (png_byte) '\0', /* sPLT */ + 116, 73, 77, 69, (png_byte) '\0', /* tIME */ + }; + #endif + + ... + + #if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED) + /* ignore all unknown chunks: */ + png_set_keep_unknown_chunks(read_ptr, 1, NULL, 0); + /* except for vpAg: */ + png_set_keep_unknown_chunks(read_ptr, 2, vpAg, 1); + /* also ignore unused known chunks: */ + png_set_keep_unknown_chunks(read_ptr, 1, unused_chunks, + (int)sizeof(unused_chunks)/5); + #endif + +User limits + +The PNG specification allows the width and height of an image to be as +large as 2^31-1 (0x7fffffff), or about 2.147 billion rows and columns. +Since very few applications really need to process such large images, +we have imposed an arbitrary 1-million limit on rows and columns. +Larger images will be rejected immediately with a png_error() call. If +you wish to override this limit, you can use + + png_set_user_limits(png_ptr, width_max, height_max); + +to set your own limits, or use width_max = height_max = 0x7fffffffL +to allow all valid dimensions (libpng may reject some very large images +anyway because of potential buffer overflow conditions). + +You should put this statement after you create the PNG structure and +before calling png_read_info(), png_read_png(), or png_process_data(). +If you need to retrieve the limits that are being applied, use + + width_max = png_get_user_width_max(png_ptr); + height_max = png_get_user_height_max(png_ptr); + +The PNG specification sets no limit on the number of ancillary chunks +allowed in a PNG datastream. You can impose a limit on the total number +of sPLT, tEXt, iTXt, zTXt, and unknown chunks that will be stored, with + + png_set_chunk_cache_max(png_ptr, user_chunk_cache_max); + +where 0x7fffffffL means unlimited. You can retrieve this limit with + + chunk_cache_max = png_get_chunk_cache_max(png_ptr); + +This limit also applies to the number of buffers that can be allocated +by png_decompress_chunk() while decompressing iTXt, zTXt, and iCCP chunks. + +You can also set a limit on the amount of memory that a compressed chunk +other than IDAT can occupy, with + + png_set_chunk_malloc_max(png_ptr, user_chunk_malloc_max); + +and you can retrieve the limit with + + chunk_malloc_max = png_get_chunk_malloc_max(png_ptr); + +Any chunks that would cause either of these limits to be exceeded will +be ignored. + +The high-level read interface + +At this point there are two ways to proceed; through the high-level +read interface, or through a sequence of low-level read operations. +You can use the high-level interface if (a) you are willing to read +the entire image into memory, and (b) the input transformations +you want to do are limited to the following set: + + PNG_TRANSFORM_IDENTITY No transformation + PNG_TRANSFORM_STRIP_16 Strip 16-bit samples to + 8 bits + PNG_TRANSFORM_STRIP_ALPHA Discard the alpha channel + PNG_TRANSFORM_PACKING Expand 1, 2 and 4-bit + samples to bytes + PNG_TRANSFORM_PACKSWAP Change order of packed + pixels to LSB first + PNG_TRANSFORM_EXPAND Perform set_expand() + PNG_TRANSFORM_INVERT_MONO Invert monochrome images + PNG_TRANSFORM_SHIFT Normalize pixels to the + sBIT depth + PNG_TRANSFORM_BGR Flip RGB to BGR, RGBA + to BGRA + PNG_TRANSFORM_SWAP_ALPHA Flip RGBA to ARGB or GA + to AG + PNG_TRANSFORM_INVERT_ALPHA Change alpha from opacity + to transparency + PNG_TRANSFORM_SWAP_ENDIAN Byte-swap 16-bit samples + PNG_TRANSFORM_GRAY_TO_RGB Expand grayscale samples + to RGB (or GA to RGBA) + +(This excludes setting a background color, doing gamma transformation, +quantizing, and setting filler.) If this is the case, simply do this: + + png_read_png(png_ptr, info_ptr, png_transforms, NULL) + +where png_transforms is an integer containing the bitwise OR of some +set of transformation flags. This call is equivalent to png_read_info(), +followed the set of transformations indicated by the transform mask, +then png_read_image(), and finally png_read_end(). + +(The final parameter of this call is not yet used. Someday it might point +to transformation parameters required by some future input transform.) + +You must use png_transforms and not call any png_set_transform() functions +when you use png_read_png(). + +After you have called png_read_png(), you can retrieve the image data +with + + row_pointers = png_get_rows(png_ptr, info_ptr); + +where row_pointers is an array of pointers to the pixel data for each row: + + png_bytep row_pointers[height]; + +If you know your image size and pixel size ahead of time, you can allocate +row_pointers prior to calling png_read_png() with + + if (height > PNG_UINT_32_MAX/png_sizeof(png_byte)) + png_error (png_ptr, + "Image is too tall to process in memory"); + if (width > PNG_UINT_32_MAX/pixel_size) + png_error (png_ptr, + "Image is too wide to process in memory"); + row_pointers = png_malloc(png_ptr, + height*png_sizeof(png_bytep)); + for (int i=0; i) and +png_get_(png_ptr, info_ptr, ...) functions return non-zero if the +data has been read, or zero if it is missing. The parameters to the +png_get_ are set directly if they are simple data types, or a +pointer into the info_ptr is returned for any complex types. + + png_get_PLTE(png_ptr, info_ptr, &palette, + &num_palette); + palette - the palette for the file + (array of png_color) + num_palette - number of entries in the palette + + png_get_gAMA(png_ptr, info_ptr, &gamma); + gamma - the gamma the file is written + at (PNG_INFO_gAMA) + + png_get_sRGB(png_ptr, info_ptr, &srgb_intent); + srgb_intent - the rendering intent (PNG_INFO_sRGB) + The presence of the sRGB chunk + means that the pixel data is in the + sRGB color space. This chunk also + implies specific values of gAMA and + cHRM. + + png_get_iCCP(png_ptr, info_ptr, &name, + &compression_type, &profile, &proflen); + name - The profile name. + compression - The compression type; always + PNG_COMPRESSION_TYPE_BASE for PNG 1.0. + You may give NULL to this argument to + ignore it. + profile - International Color Consortium color + profile data. May contain NULs. + proflen - length of profile data in bytes. + + png_get_sBIT(png_ptr, info_ptr, &sig_bit); + sig_bit - the number of significant bits for + (PNG_INFO_sBIT) each of the gray, + red, green, and blue channels, + whichever are appropriate for the + given color type (png_color_16) + + png_get_tRNS(png_ptr, info_ptr, &trans_alpha, + &num_trans, &trans_color); + trans_alpha - array of alpha (transparency) + entries for palette (PNG_INFO_tRNS) + trans_color - graylevel or color sample values of + the single transparent color for + non-paletted images (PNG_INFO_tRNS) + num_trans - number of transparent entries + (PNG_INFO_tRNS) + + png_get_hIST(png_ptr, info_ptr, &hist); + (PNG_INFO_hIST) + hist - histogram of palette (array of + png_uint_16) + + png_get_tIME(png_ptr, info_ptr, &mod_time); + mod_time - time image was last modified + (PNG_VALID_tIME) + + png_get_bKGD(png_ptr, info_ptr, &background); + background - background color (PNG_VALID_bKGD) + valid 16-bit red, green and blue + values, regardless of color_type + + num_comments = png_get_text(png_ptr, info_ptr, + &text_ptr, &num_text); + num_comments - number of comments + text_ptr - array of png_text holding image + comments + text_ptr[i].compression - type of compression used + on "text" PNG_TEXT_COMPRESSION_NONE + PNG_TEXT_COMPRESSION_zTXt + PNG_ITXT_COMPRESSION_NONE + PNG_ITXT_COMPRESSION_zTXt + text_ptr[i].key - keyword for comment. Must contain + 1-79 characters. + text_ptr[i].text - text comments for current + keyword. Can be empty. + text_ptr[i].text_length - length of text string, + after decompression, 0 for iTXt + text_ptr[i].itxt_length - length of itxt string, + after decompression, 0 for tEXt/zTXt + text_ptr[i].lang - language of comment (empty + string for unknown). + text_ptr[i].lang_key - keyword in UTF-8 + (empty string for unknown). + Note that the itxt_length, lang, and lang_key + members of the text_ptr structure only exist + when the library is built with iTXt chunk support. + + num_text - number of comments (same as + num_comments; you can put NULL here + to avoid the duplication) + Note while png_set_text() will accept text, language, + and translated keywords that can be NULL pointers, the + structure returned by png_get_text will always contain + regular zero-terminated C strings. They might be + empty strings but they will never be NULL pointers. + + num_spalettes = png_get_sPLT(png_ptr, info_ptr, + &palette_ptr); + palette_ptr - array of palette structures holding + contents of one or more sPLT chunks + read. + num_spalettes - number of sPLT chunks read. + + png_get_oFFs(png_ptr, info_ptr, &offset_x, &offset_y, + &unit_type); + offset_x - positive offset from the left edge + of the screen + offset_y - positive offset from the top edge + of the screen + unit_type - PNG_OFFSET_PIXEL, PNG_OFFSET_MICROMETER + + png_get_pHYs(png_ptr, info_ptr, &res_x, &res_y, + &unit_type); + res_x - pixels/unit physical resolution in + x direction + res_y - pixels/unit physical resolution in + x direction + unit_type - PNG_RESOLUTION_UNKNOWN, + PNG_RESOLUTION_METER + + png_get_sCAL(png_ptr, info_ptr, &unit, &width, + &height) + unit - physical scale units (an integer) + width - width of a pixel in physical scale units + height - height of a pixel in physical scale units + (width and height are doubles) + + png_get_sCAL_s(png_ptr, info_ptr, &unit, &width, + &height) + unit - physical scale units (an integer) + width - width of a pixel in physical scale units + height - height of a pixel in physical scale units + (width and height are strings like "2.54") + + num_unknown_chunks = png_get_unknown_chunks(png_ptr, + info_ptr, &unknowns) + unknowns - array of png_unknown_chunk + structures holding unknown chunks + unknowns[i].name - name of unknown chunk + unknowns[i].data - data of unknown chunk + unknowns[i].size - size of unknown chunk's data + unknowns[i].location - position of chunk in file + + The value of "i" corresponds to the order in which the + chunks were read from the PNG file or inserted with the + png_set_unknown_chunks() function. + +The data from the pHYs chunk can be retrieved in several convenient +forms: + + res_x = png_get_x_pixels_per_meter(png_ptr, + info_ptr) + res_y = png_get_y_pixels_per_meter(png_ptr, + info_ptr) + res_x_and_y = png_get_pixels_per_meter(png_ptr, + info_ptr) + res_x = png_get_x_pixels_per_inch(png_ptr, + info_ptr) + res_y = png_get_y_pixels_per_inch(png_ptr, + info_ptr) + res_x_and_y = png_get_pixels_per_inch(png_ptr, + info_ptr) + aspect_ratio = png_get_pixel_aspect_ratio(png_ptr, + info_ptr) + + (Each of these returns 0 [signifying "unknown"] if + the data is not present or if res_x is 0; + res_x_and_y is 0 if res_x != res_y) + +The data from the oFFs chunk can be retrieved in several convenient +forms: + + x_offset = png_get_x_offset_microns(png_ptr, info_ptr); + y_offset = png_get_y_offset_microns(png_ptr, info_ptr); + x_offset = png_get_x_offset_inches(png_ptr, info_ptr); + y_offset = png_get_y_offset_inches(png_ptr, info_ptr); + + (Each of these returns 0 [signifying "unknown" if both + x and y are 0] if the data is not present or if the + chunk is present but the unit is the pixel) + +For more information, see the png_info definition in png.h and the +PNG specification for chunk contents. Be careful with trusting +rowbytes, as some of the transformations could increase the space +needed to hold a row (expand, filler, gray_to_rgb, etc.). +See png_read_update_info(), below. + +A quick word about text_ptr and num_text. PNG stores comments in +keyword/text pairs, one pair per chunk, with no limit on the number +of text chunks, and a 2^31 byte limit on their size. While there are +suggested keywords, there is no requirement to restrict the use to these +strings. It is strongly suggested that keywords and text be sensible +to humans (that's the point), so don't use abbreviations. Non-printing +symbols are not allowed. See the PNG specification for more details. +There is also no requirement to have text after the keyword. + +Keywords should be limited to 79 Latin-1 characters without leading or +trailing spaces, but non-consecutive spaces are allowed within the +keyword. It is possible to have the same keyword any number of times. +The text_ptr is an array of png_text structures, each holding a +pointer to a language string, a pointer to a keyword and a pointer to +a text string. The text string, language code, and translated +keyword may be empty or NULL pointers. The keyword/text +pairs are put into the array in the order that they are received. +However, some or all of the text chunks may be after the image, so, to +make sure you have read all the text chunks, don't mess with these +until after you read the stuff after the image. This will be +mentioned again below in the discussion that goes with png_read_end(). + +Input transformations + +After you've read the header information, you can set up the library +to handle any special transformations of the image data. The various +ways to transform the data will be described in the order that they +should occur. This is important, as some of these change the color +type and/or bit depth of the data, and some others only work on +certain color types and bit depths. Even though each transformation +checks to see if it has data that it can do something with, you should +make sure to only enable a transformation if it will be valid for the +data. For example, don't swap red and blue on grayscale data. + +The colors used for the background and transparency values should be +supplied in the same format/depth as the current image data. They +are stored in the same format/depth as the image data in a bKGD or tRNS +chunk, so this is what libpng expects for this data. The colors are +transformed to keep in sync with the image data when an application +calls the png_read_update_info() routine (see below). + +Data will be decoded into the supplied row buffers packed into bytes +unless the library has been told to transform it into another format. +For example, 4 bit/pixel paletted or grayscale data will be returned +2 pixels/byte with the leftmost pixel in the high-order bits of the +byte, unless png_set_packing() is called. 8-bit RGB data will be stored +in RGB RGB RGB format unless png_set_filler() or png_set_add_alpha() +is called to insert filler bytes, either before or after each RGB triplet. +16-bit RGB data will be returned RRGGBB RRGGBB, with the most significant +byte of the color value first, unless png_set_strip_16() is called to +transform it to regular RGB RGB triplets, or png_set_filler() or +png_set_add alpha() is called to insert filler bytes, either before or +after each RRGGBB triplet. Similarly, 8-bit or 16-bit grayscale data can +be modified with +png_set_filler(), png_set_add_alpha(), or png_set_strip_16(). + +The following code transforms grayscale images of less than 8 to 8 bits, +changes paletted images to RGB, and adds a full alpha channel if there is +transparency information in a tRNS chunk. This is most useful on +grayscale images with bit depths of 2 or 4 or if there is a multiple-image +viewing application that wishes to treat all images in the same way. + + if (color_type == PNG_COLOR_TYPE_PALETTE) + png_set_palette_to_rgb(png_ptr); + + if (color_type == PNG_COLOR_TYPE_GRAY && + bit_depth < 8) png_set_expand_gray_1_2_4_to_8(png_ptr); + + if (png_get_valid(png_ptr, info_ptr, + PNG_INFO_tRNS)) png_set_tRNS_to_alpha(png_ptr); + +These three functions are actually aliases for png_set_expand(), added +in libpng version 1.0.4, with the function names expanded to improve code +readability. In some future version they may actually do different +things. + +As of libpng version 1.2.9, png_set_expand_gray_1_2_4_to_8() was +added. It expands the sample depth without changing tRNS to alpha. + +As of libpng version 1.4.4, not all possible expansions are supported. + +In the following table, the 01 means grayscale with depth<8, 31 means +indexed with depth<8, other numerals represent the color type, "T" means +the tRNS chunk is present, A means an alpha channel is present, and O +means tRNS or alpha is present but all pixels in the image are opaque. + + FROM 01 31 0 0T 0O 2 2T 2O 3 3T 3O 4A 4O 6A 6O + TO + 01 - + 31 - + 0 1 - + 0T - + 0O - + 2 GX - + 2T - + 2O - + 3 1 - + 3T - + 3O - + 4A T - + 4O - + 6A GX TX TX - + 6O GX TX - + +Within the matrix, + "-" means the transformation is not supported. + "X" means the transformation is obtained by png_set_expand(). + "1" means the transformation is obtained by + png_set_expand_gray_1_2_4_to_8 + "G" means the transformation is obtained by + png_set_gray_to_rgb(). + "P" means the transformation is obtained by + png_set_expand_palette_to_rgb(). + "T" means the transformation is obtained by + png_set_tRNS_to_alpha(). + +PNG can have files with 16 bits per channel. If you only can handle +8 bits per channel, this will strip the pixels down to 8 bit. + + if (bit_depth == 16) + png_set_strip_16(png_ptr); + +If, for some reason, you don't need the alpha channel on an image, +and you want to remove it rather than combining it with the background +(but the image author certainly had in mind that you *would* combine +it with the background, so that's what you should probably do): + + if (color_type & PNG_COLOR_MASK_ALPHA) + png_set_strip_alpha(png_ptr); + +In PNG files, the alpha channel in an image +is the level of opacity. If you need the alpha channel in an image to +be the level of transparency instead of opacity, you can invert the +alpha channel (or the tRNS chunk data) after it's read, so that 0 is +fully opaque and 255 (in 8-bit or paletted images) or 65535 (in 16-bit +images) is fully transparent, with + + png_set_invert_alpha(png_ptr); + +PNG files pack pixels of bit depths 1, 2, and 4 into bytes as small as +they can, resulting in, for example, 8 pixels per byte for 1 bit +files. This code expands to 1 pixel per byte without changing the +values of the pixels: + + if (bit_depth < 8) + png_set_packing(png_ptr); + +PNG files have possible bit depths of 1, 2, 4, 8, and 16. All pixels +stored in a PNG image have been "scaled" or "shifted" up to the next +higher possible bit depth (e.g. from 5 bits/sample in the range [0,31] +to 8 bits/sample in the range [0, 255]). However, it is also possible +to convert the PNG pixel data back to the original bit depth of the +image. This call reduces the pixels back down to the original bit depth: + + png_color_8p sig_bit; + + if (png_get_sBIT(png_ptr, info_ptr, &sig_bit)) + png_set_shift(png_ptr, sig_bit); + +PNG files store 3-color pixels in red, green, blue order. This code +changes the storage of the pixels to blue, green, red: + + if (color_type == PNG_COLOR_TYPE_RGB || + color_type == PNG_COLOR_TYPE_RGB_ALPHA) + png_set_bgr(png_ptr); + +PNG files store RGB pixels packed into 3 or 6 bytes. This code expands them +into 4 or 8 bytes for windowing systems that need them in this format: + + if (color_type == PNG_COLOR_TYPE_RGB) + png_set_filler(png_ptr, filler, PNG_FILLER_BEFORE); + +where "filler" is the 8 or 16-bit number to fill with, and the location is +either PNG_FILLER_BEFORE or PNG_FILLER_AFTER, depending upon whether +you want the filler before the RGB or after. This transformation +does not affect images that already have full alpha channels. To add an +opaque alpha channel, use filler=0xff or 0xffff and PNG_FILLER_AFTER which +will generate RGBA pixels. + +Note that png_set_filler() does not change the color type. If you want +to do that, you can add a true alpha channel with + + if (color_type == PNG_COLOR_TYPE_RGB || + color_type == PNG_COLOR_TYPE_GRAY) + png_set_add_alpha(png_ptr, filler, PNG_FILLER_AFTER); + +where "filler" contains the alpha value to assign to each pixel. +This function was added in libpng-1.2.7. + +If you are reading an image with an alpha channel, and you need the +data as ARGB instead of the normal PNG format RGBA: + + if (color_type == PNG_COLOR_TYPE_RGB_ALPHA) + png_set_swap_alpha(png_ptr); + +For some uses, you may want a grayscale image to be represented as +RGB. This code will do that conversion: + + if (color_type == PNG_COLOR_TYPE_GRAY || + color_type == PNG_COLOR_TYPE_GRAY_ALPHA) + png_set_gray_to_rgb(png_ptr); + +Conversely, you can convert an RGB or RGBA image to grayscale or grayscale +with alpha. + + if (color_type == PNG_COLOR_TYPE_RGB || + color_type == PNG_COLOR_TYPE_RGB_ALPHA) + png_set_rgb_to_gray_fixed(png_ptr, error_action, + int red_weight, int green_weight); + + error_action = 1: silently do the conversion + error_action = 2: issue a warning if the original + image has any pixel where + red != green or red != blue + error_action = 3: issue an error and abort the + conversion if the original + image has any pixel where + red != green or red != blue + + red_weight: weight of red component times 100000 + green_weight: weight of green component times 100000 + If either weight is negative, default + weights (21268, 71514) are used. + +If you have set error_action = 1 or 2, you can +later check whether the image really was gray, after processing +the image rows, with the png_get_rgb_to_gray_status(png_ptr) function. +It will return a png_byte that is zero if the image was gray or +1 if there were any non-gray pixels. bKGD and sBIT data +will be silently converted to grayscale, using the green channel +data, regardless of the error_action setting. + +With red_weight+green_weight<=100000, +the normalized graylevel is computed: + + int rw = red_weight * 65536; + int gw = green_weight * 65536; + int bw = 65536 - (rw + gw); + gray = (rw*red + gw*green + bw*blue)/65536; + +The default values approximate those recommended in the Charles +Poynton's Color FAQ, +Copyright (c) 1998-01-04 Charles Poynton + + Y = 0.212671 * R + 0.715160 * G + 0.072169 * B + +Libpng approximates this with + + Y = 0.21268 * R + 0.7151 * G + 0.07217 * B + +which can be expressed with integers as + + Y = (6969 * R + 23434 * G + 2365 * B)/32768 + +The calculation is done in a linear colorspace, if the image gamma +is known. + +If you have a grayscale and you are using png_set_expand_depth(), +png_set_expand(), or png_set_gray_to_rgb to change to truecolor or to +a higher bit-depth, you must either supply the background color as a gray +value at the original file bit-depth (need_expand = 1) or else supply the +background color as an RGB triplet at the final, expanded bit depth +(need_expand = 0). Similarly, if you are reading a paletted image, you +must either supply the background color as a palette index (need_expand = 1) +or as an RGB triplet that may or may not be in the palette (need_expand = 0). + + png_color_16 my_background; + png_color_16p image_background; + + if (png_get_bKGD(png_ptr, info_ptr, &image_background)) + png_set_background(png_ptr, image_background, + PNG_BACKGROUND_GAMMA_FILE, 1, 1.0); + else + png_set_background(png_ptr, &my_background, + PNG_BACKGROUND_GAMMA_SCREEN, 0, 1.0); + +The png_set_background() function tells libpng to composite images +with alpha or simple transparency against the supplied background +color. If the PNG file contains a bKGD chunk (PNG_INFO_bKGD valid), +you may use this color, or supply another color more suitable for +the current display (e.g., the background color from a web page). You +need to tell libpng whether the color is in the gamma space of the +display (PNG_BACKGROUND_GAMMA_SCREEN for colors you supply), the file +(PNG_BACKGROUND_GAMMA_FILE for colors from the bKGD chunk), or one +that is neither of these gammas (PNG_BACKGROUND_GAMMA_UNIQUE - I don't +know why anyone would use this, but it's here). + +To properly display PNG images on any kind of system, the application needs +to know what the display gamma is. Ideally, the user will know this, and +the application will allow them to set it. One method of allowing the user +to set the display gamma separately for each system is to check for a +SCREEN_GAMMA or DISPLAY_GAMMA environment variable, which will hopefully be +correctly set. + +Note that display_gamma is the overall gamma correction required to produce +pleasing results, which depends on the lighting conditions in the surrounding +environment. In a dim or brightly lit room, no compensation other than +the physical gamma exponent of the monitor is needed, while in a dark room +a slightly smaller exponent is better. + + double gamma, screen_gamma; + + if (/* We have a user-defined screen + gamma value */) + { + screen_gamma = user_defined_screen_gamma; + } + /* One way that applications can share the same + screen gamma value */ + else if ((gamma_str = getenv("SCREEN_GAMMA")) + != NULL) + { + screen_gamma = (double)atof(gamma_str); + } + /* If we don't have another value */ + else + { + screen_gamma = 2.2; /* A good guess for a + PC monitor in a bright office or a dim room */ + screen_gamma = 2.0; /* A good guess for a + PC monitor in a dark room */ + screen_gamma = 1.7 or 1.0; /* A good + guess for Mac systems */ + } + +The png_set_gamma() function handles gamma transformations of the data. +Pass both the file gamma and the current screen_gamma. If the file does +not have a gamma value, you can pass one anyway if you have an idea what +it is (usually 0.45455 is a good guess for GIF images on PCs). Note +that file gammas are inverted from screen gammas. See the discussions +on gamma in the PNG specification for an excellent description of what +gamma is, and why all applications should support it. It is strongly +recommended that PNG viewers support gamma correction. + + if (png_get_gAMA(png_ptr, info_ptr, &gamma)) + png_set_gamma(png_ptr, screen_gamma, gamma); + else + png_set_gamma(png_ptr, screen_gamma, 0.45455); + +If you need to reduce an RGB file to a paletted file, or if a paletted +file has more entries then will fit on your screen, png_set_quantize() +will do that. Note that this is a simple match dither that merely +finds the closest color available. This should work fairly well with +optimized palettes, and fairly badly with linear color cubes. If you +pass a palette that is larger then maximum_colors, the file will +reduce the number of colors in the palette so it will fit into +maximum_colors. If there is a histogram, it will use it to make +more intelligent choices when reducing the palette. If there is no +histogram, it may not do as good a job. + + if (color_type & PNG_COLOR_MASK_COLOR) + { + if (png_get_valid(png_ptr, info_ptr, + PNG_INFO_PLTE)) + { + png_uint_16p histogram = NULL; + + png_get_hIST(png_ptr, info_ptr, + &histogram); + png_set_quantize(png_ptr, palette, num_palette, + max_screen_colors, histogram, 1); + } + else + { + png_color std_color_cube[MAX_SCREEN_COLORS] = + { ... colors ... }; + + png_set_quantize(png_ptr, std_color_cube, + MAX_SCREEN_COLORS, MAX_SCREEN_COLORS, + NULL,0); + } + } + +PNG files describe monochrome as black being zero and white being one. +The following code will reverse this (make black be one and white be +zero): + + if (bit_depth == 1 && color_type == PNG_COLOR_TYPE_GRAY) + png_set_invert_mono(png_ptr); + +This function can also be used to invert grayscale and gray-alpha images: + + if (color_type == PNG_COLOR_TYPE_GRAY || + color_type == PNG_COLOR_TYPE_GRAY_ALPHA) + png_set_invert_mono(png_ptr); + +PNG files store 16 bit pixels in network byte order (big-endian, +ie. most significant bits first). This code changes the storage to the +other way (little-endian, i.e. least significant bits first, the +way PCs store them): + + if (bit_depth == 16) + png_set_swap(png_ptr); + +If you are using packed-pixel images (1, 2, or 4 bits/pixel), and you +need to change the order the pixels are packed into bytes, you can use: + + if (bit_depth < 8) + png_set_packswap(png_ptr); + +Finally, you can write your own transformation function if none of +the existing ones meets your needs. This is done by setting a callback +with + + png_set_read_user_transform_fn(png_ptr, + read_transform_fn); + +You must supply the function + + void read_transform_fn(png_ptr ptr, row_info_ptr + row_info, png_bytep data) + +See pngtest.c for a working example. Your function will be called +after all of the other transformations have been processed. + +You can also set up a pointer to a user structure for use by your +callback function, and you can inform libpng that your transform +function will change the number of channels or bit depth with the +function + + png_set_user_transform_info(png_ptr, user_ptr, + user_depth, user_channels); + +The user's application, not libpng, is responsible for allocating and +freeing any memory required for the user structure. + +You can retrieve the pointer via the function +png_get_user_transform_ptr(). For example: + + voidp read_user_transform_ptr = + png_get_user_transform_ptr(png_ptr); + +The last thing to handle is interlacing; this is covered in detail below, +but you must call the function here if you want libpng to handle expansion +of the interlaced image. + + number_of_passes = png_set_interlace_handling(png_ptr); + +After setting the transformations, libpng can update your png_info +structure to reflect any transformations you've requested with this +call. This is most useful to update the info structure's rowbytes +field so you can use it to allocate your image memory. This function +will also update your palette with the correct screen_gamma and +background if these have been given with the calls above. + + png_read_update_info(png_ptr, info_ptr); + +After you call png_read_update_info(), you can allocate any +memory you need to hold the image. The row data is simply +raw byte data for all forms of images. As the actual allocation +varies among applications, no example will be given. If you +are allocating one large chunk, you will need to build an +array of pointers to each row, as it will be needed for some +of the functions below. + +Reading image data + +After you've allocated memory, you can read the image data. +The simplest way to do this is in one function call. If you are +allocating enough memory to hold the whole image, you can just +call png_read_image() and libpng will read in all the image data +and put it in the memory area supplied. You will need to pass in +an array of pointers to each row. + +This function automatically handles interlacing, so you don't need +to call png_set_interlace_handling() or call this function multiple +times, or any of that other stuff necessary with png_read_rows(). + + png_read_image(png_ptr, row_pointers); + +where row_pointers is: + + png_bytep row_pointers[height]; + +You can point to void or char or whatever you use for pixels. + +If you don't want to read in the whole image at once, you can +use png_read_rows() instead. If there is no interlacing (check +interlace_type == PNG_INTERLACE_NONE), this is simple: + + png_read_rows(png_ptr, row_pointers, NULL, + number_of_rows); + +where row_pointers is the same as in the png_read_image() call. + +If you are doing this just one row at a time, you can do this with +a single row_pointer instead of an array of row_pointers: + + png_bytep row_pointer = row; + png_read_row(png_ptr, row_pointer, NULL); + +If the file is interlaced (interlace_type != 0 in the IHDR chunk), things +get somewhat harder. The only current (PNG Specification version 1.2) +interlacing type for PNG is (interlace_type == PNG_INTERLACE_ADAM7) +is a somewhat complicated 2D interlace scheme, known as Adam7, that +breaks down an image into seven smaller images of varying size, based +on an 8x8 grid. + +libpng can fill out those images or it can give them to you "as is". +If you want them filled out, there are two ways to do that. The one +mentioned in the PNG specification is to expand each pixel to cover +those pixels that have not been read yet (the "rectangle" method). +This results in a blocky image for the first pass, which gradually +smooths out as more pixels are read. The other method is the "sparkle" +method, where pixels are drawn only in their final locations, with the +rest of the image remaining whatever colors they were initialized to +before the start of the read. The first method usually looks better, +but tends to be slower, as there are more pixels to put in the rows. + +If you don't want libpng to handle the interlacing details, just call +png_read_rows() seven times to read in all seven images. Each of the +images is a valid image by itself, or they can all be combined on an +8x8 grid to form a single image (although if you intend to combine them +you would be far better off using the libpng interlace handling). + +The first pass will return an image 1/8 as wide as the entire image +(every 8th column starting in column 0) and 1/8 as high as the original +(every 8th row starting in row 0), the second will be 1/8 as wide +(starting in column 4) and 1/8 as high (also starting in row 0). The +third pass will be 1/4 as wide (every 4th pixel starting in column 0) and +1/8 as high (every 8th row starting in row 4), and the fourth pass will +be 1/4 as wide and 1/4 as high (every 4th column starting in column 2, +and every 4th row starting in row 0). The fifth pass will return an +image 1/2 as wide, and 1/4 as high (starting at column 0 and row 2), +while the sixth pass will be 1/2 as wide and 1/2 as high as the original +(starting in column 1 and row 0). The seventh and final pass will be as +wide as the original, and 1/2 as high, containing all of the odd +numbered scanlines. Phew! + +If you want libpng to expand the images, call this before calling +png_start_read_image() or png_read_update_info(): + + if (interlace_type == PNG_INTERLACE_ADAM7) + number_of_passes + = png_set_interlace_handling(png_ptr); + +This will return the number of passes needed. Currently, this +is seven, but may change if another interlace type is added. +This function can be called even if the file is not interlaced, +where it will return one pass. + +If you are not going to display the image after each pass, but are +going to wait until the entire image is read in, use the sparkle +effect. This effect is faster and the end result of either method +is exactly the same. If you are planning on displaying the image +after each pass, the "rectangle" effect is generally considered the +better looking one. + +If you only want the "sparkle" effect, just call png_read_rows() as +normal, with the third parameter NULL. Make sure you make pass over +the image number_of_passes times, and you don't change the data in the +rows between calls. You can change the locations of the data, just +not the data. Each pass only writes the pixels appropriate for that +pass, and assumes the data from previous passes is still valid. + + png_read_rows(png_ptr, row_pointers, NULL, + number_of_rows); + +If you only want the first effect (the rectangles), do the same as +before except pass the row buffer in the third parameter, and leave +the second parameter NULL. + + png_read_rows(png_ptr, NULL, row_pointers, + number_of_rows); + +Finishing a sequential read + +After you are finished reading the image through the +low-level interface, you can finish reading the file. If you are +interested in comments or time, which may be stored either before or +after the image data, you should pass the separate png_info struct if +you want to keep the comments from before and after the image +separate. If you are not interested, you can pass NULL. + + png_read_end(png_ptr, end_info); + +When you are done, you can free all memory allocated by libpng like this: + + png_destroy_read_struct(&png_ptr, &info_ptr, + &end_info); + +It is also possible to individually free the info_ptr members that +point to libpng-allocated storage with the following function: + + png_free_data(png_ptr, info_ptr, mask, seq) + mask - identifies data to be freed, a mask + containing the bitwise OR of one or + more of + PNG_FREE_PLTE, PNG_FREE_TRNS, + PNG_FREE_HIST, PNG_FREE_ICCP, + PNG_FREE_PCAL, PNG_FREE_ROWS, + PNG_FREE_SCAL, PNG_FREE_SPLT, + PNG_FREE_TEXT, PNG_FREE_UNKN, + or simply PNG_FREE_ALL + seq - sequence number of item to be freed + (-1 for all items) + +This function may be safely called when the relevant storage has +already been freed, or has not yet been allocated, or was allocated +by the user and not by libpng, and will in those cases do nothing. +The "seq" parameter is ignored if only one item of the selected data +type, such as PLTE, is allowed. If "seq" is not -1, and multiple items +are allowed for the data type identified in the mask, such as text or +sPLT, only the n'th item in the structure is freed, where n is "seq". + +The default behavior is only to free data that was allocated internally +by libpng. This can be changed, so that libpng will not free the data, +or so that it will free data that was allocated by the user with png_malloc() +or png_zalloc() and passed in via a png_set_*() function, with + + png_data_freer(png_ptr, info_ptr, freer, mask) + mask - which data elements are affected + same choices as in png_free_data() + freer - one of + PNG_DESTROY_WILL_FREE_DATA + PNG_SET_WILL_FREE_DATA + PNG_USER_WILL_FREE_DATA + +This function only affects data that has already been allocated. +You can call this function after reading the PNG data but before calling +any png_set_*() functions, to control whether the user or the png_set_*() +function is responsible for freeing any existing data that might be present, +and again after the png_set_*() functions to control whether the user +or png_destroy_*() is supposed to free the data. When the user assumes +responsibility for libpng-allocated data, the application must use +png_free() to free it, and when the user transfers responsibility to libpng +for data that the user has allocated, the user must have used png_malloc() +or png_zalloc() to allocate it. + +If you allocated your row_pointers in a single block, as suggested above in +the description of the high level read interface, you must not transfer +responsibility for freeing it to the png_set_rows or png_read_destroy function, +because they would also try to free the individual row_pointers[i]. + +If you allocated text_ptr.text, text_ptr.lang, and text_ptr.translated_keyword +separately, do not transfer responsibility for freeing text_ptr to libpng, +because when libpng fills a png_text structure it combines these members with +the key member, and png_free_data() will free only text_ptr.key. Similarly, +if you transfer responsibility for free'ing text_ptr from libpng to your +application, your application must not separately free those members. + +The png_free_data() function will turn off the "valid" flag for anything +it frees. If you need to turn the flag off for a chunk that was freed by +your application instead of by libpng, you can use + + png_set_invalid(png_ptr, info_ptr, mask); + mask - identifies the chunks to be made invalid, + containing the bitwise OR of one or + more of + PNG_INFO_gAMA, PNG_INFO_sBIT, + PNG_INFO_cHRM, PNG_INFO_PLTE, + PNG_INFO_tRNS, PNG_INFO_bKGD, + PNG_INFO_hIST, PNG_INFO_pHYs, + PNG_INFO_oFFs, PNG_INFO_tIME, + PNG_INFO_pCAL, PNG_INFO_sRGB, + PNG_INFO_iCCP, PNG_INFO_sPLT, + PNG_INFO_sCAL, PNG_INFO_IDAT + +For a more compact example of reading a PNG image, see the file example.c. + +Reading PNG files progressively + +The progressive reader is slightly different then the non-progressive +reader. Instead of calling png_read_info(), png_read_rows(), and +png_read_end(), you make one call to png_process_data(), which calls +callbacks when it has the info, a row, or the end of the image. You +set up these callbacks with png_set_progressive_read_fn(). You don't +have to worry about the input/output functions of libpng, as you are +giving the library the data directly in png_process_data(). I will +assume that you have read the section on reading PNG files above, +so I will only highlight the differences (although I will show +all of the code). + +png_structp png_ptr; +png_infop info_ptr; + + /* An example code fragment of how you would + initialize the progressive reader in your + application. */ + int + initialize_png_reader() + { + png_ptr = png_create_read_struct + (PNG_LIBPNG_VER_STRING, (png_voidp)user_error_ptr, + user_error_fn, user_warning_fn); + if (!png_ptr) + return (ERROR); + info_ptr = png_create_info_struct(png_ptr); + if (!info_ptr) + { + png_destroy_read_struct(&png_ptr, (png_infopp)NULL, + (png_infopp)NULL); + return (ERROR); + } + + if (setjmp(png_jmpbuf(png_ptr))) + { + png_destroy_read_struct(&png_ptr, &info_ptr, + (png_infopp)NULL); + return (ERROR); + } + + /* This one's new. You can provide functions + to be called when the header info is valid, + when each row is completed, and when the image + is finished. If you aren't using all functions, + you can specify NULL parameters. Even when all + three functions are NULL, you need to call + png_set_progressive_read_fn(). You can use + any struct as the user_ptr (cast to a void pointer + for the function call), and retrieve the pointer + from inside the callbacks using the function + + png_get_progressive_ptr(png_ptr); + + which will return a void pointer, which you have + to cast appropriately. + */ + png_set_progressive_read_fn(png_ptr, (void *)user_ptr, + info_callback, row_callback, end_callback); + + return 0; + } + + /* A code fragment that you call as you receive blocks + of data */ + int + process_data(png_bytep buffer, png_uint_32 length) + { + if (setjmp(png_jmpbuf(png_ptr))) + { + png_destroy_read_struct(&png_ptr, &info_ptr, + (png_infopp)NULL); + return (ERROR); + } + + /* This one's new also. Simply give it a chunk + of data from the file stream (in order, of + course). On machines with segmented memory + models machines, don't give it any more than + 64K. The library seems to run fine with sizes + of 4K. Although you can give it much less if + necessary (I assume you can give it chunks of + 1 byte, I haven't tried less then 256 bytes + yet). When this function returns, you may + want to display any rows that were generated + in the row callback if you don't already do + so there. + */ + png_process_data(png_ptr, info_ptr, buffer, length); + return 0; + } + + /* This function is called (as set by + png_set_progressive_read_fn() above) when enough data + has been supplied so all of the header has been + read. + */ + void + info_callback(png_structp png_ptr, png_infop info) + { + /* Do any setup here, including setting any of + the transformations mentioned in the Reading + PNG files section. For now, you _must_ call + either png_start_read_image() or + png_read_update_info() after all the + transformations are set (even if you don't set + any). You may start getting rows before + png_process_data() returns, so this is your + last chance to prepare for that. + */ + } + + /* This function is called when each row of image + data is complete */ + void + row_callback(png_structp png_ptr, png_bytep new_row, + png_uint_32 row_num, int pass) + { + /* If the image is interlaced, and you turned + on the interlace handler, this function will + be called for every row in every pass. Some + of these rows will not be changed from the + previous pass. When the row is not changed, + the new_row variable will be NULL. The rows + and passes are called in order, so you don't + really need the row_num and pass, but I'm + supplying them because it may make your life + easier. + + For the non-NULL rows of interlaced images, + you must call png_progressive_combine_row() + passing in the row and the old row. You can + call this function for NULL rows (it will just + return) and for non-interlaced images (it just + does the memcpy for you) if it will make the + code easier. Thus, you can just do this for + all cases: + */ + + png_progressive_combine_row(png_ptr, old_row, + new_row); + + /* where old_row is what was displayed for + previously for the row. Note that the first + pass (pass == 0, really) will completely cover + the old row, so the rows do not have to be + initialized. After the first pass (and only + for interlaced images), you will have to pass + the current row, and the function will combine + the old row and the new row. + */ + } + + void + end_callback(png_structp png_ptr, png_infop info) + { + /* This function is called after the whole image + has been read, including any chunks after the + image (up to and including the IEND). You + will usually have the same info chunk as you + had in the header, although some data may have + been added to the comments and time fields. + + Most people won't do much here, perhaps setting + a flag that marks the image as finished. + */ + } + + + +IV. Writing + +Much of this is very similar to reading. However, everything of +importance is repeated here, so you won't have to constantly look +back up in the reading section to understand writing. + +Setup + +You will want to do the I/O initialization before you get into libpng, +so if it doesn't work, you don't have anything to undo. If you are not +using the standard I/O functions, you will need to replace them with +custom writing functions. See the discussion under Customizing libpng. + + FILE *fp = fopen(file_name, "wb"); + if (!fp) + { + return (ERROR); + } + +Next, png_struct and png_info need to be allocated and initialized. +As these can be both relatively large, you may not want to store these +on the stack, unless you have stack space to spare. Of course, you +will want to check if they return NULL. If you are also reading, +you won't want to name your read structure and your write structure +both "png_ptr"; you can call them anything you like, such as +"read_ptr" and "write_ptr". Look at pngtest.c, for example. + + png_structp png_ptr = png_create_write_struct + (PNG_LIBPNG_VER_STRING, (png_voidp)user_error_ptr, + user_error_fn, user_warning_fn); + if (!png_ptr) + return (ERROR); + + png_infop info_ptr = png_create_info_struct(png_ptr); + if (!info_ptr) + { + png_destroy_write_struct(&png_ptr, + (png_infopp)NULL); + return (ERROR); + } + +If you want to use your own memory allocation routines, +define PNG_USER_MEM_SUPPORTED and use +png_create_write_struct_2() instead of png_create_write_struct(): + + png_structp png_ptr = png_create_write_struct_2 + (PNG_LIBPNG_VER_STRING, (png_voidp)user_error_ptr, + user_error_fn, user_warning_fn, (png_voidp) + user_mem_ptr, user_malloc_fn, user_free_fn); + +After you have these structures, you will need to set up the +error handling. When libpng encounters an error, it expects to +longjmp() back to your routine. Therefore, you will need to call +setjmp() and pass the png_jmpbuf(png_ptr). If you +write the file from different routines, you will need to update +the png_jmpbuf(png_ptr) every time you enter a new routine that will +call a png_*() function. See your documentation of setjmp/longjmp +for your compiler for more information on setjmp/longjmp. See +the discussion on libpng error handling in the Customizing Libpng +section below for more information on the libpng error handling. + + if (setjmp(png_jmpbuf(png_ptr))) + { + png_destroy_write_struct(&png_ptr, &info_ptr); + fclose(fp); + return (ERROR); + } + ... + return; + +If you would rather avoid the complexity of setjmp/longjmp issues, +you can compile libpng with PNG_NO_SETJMP, in which case +errors will result in a call to PNG_ABORT() which defaults to abort(). + +You can #define PNG_ABORT() to a function that does something +more useful than abort(), as long as your function does not +return. + +Now you need to set up the output code. The default for libpng is to +use the C function fwrite(). If you use this, you will need to pass a +valid FILE * in the function png_init_io(). Be sure that the file is +opened in binary mode. Again, if you wish to handle writing data in +another way, see the discussion on libpng I/O handling in the Customizing +Libpng section below. + + png_init_io(png_ptr, fp); + +If you are embedding your PNG into a datastream such as MNG, and don't +want libpng to write the 8-byte signature, or if you have already +written the signature in your application, use + + png_set_sig_bytes(png_ptr, 8); + +to inform libpng that it should not write a signature. + +Write callbacks + +At this point, you can set up a callback function that will be +called after each row has been written, which you can use to control +a progress meter or the like. It's demonstrated in pngtest.c. +You must supply a function + + void write_row_callback(png_ptr, png_uint_32 row, + int pass); + { + /* put your code here */ + } + +(You can give it another name that you like instead of "write_row_callback") + +To inform libpng about your function, use + + png_set_write_status_fn(png_ptr, write_row_callback); + +You now have the option of modifying how the compression library will +run. The following functions are mainly for testing, but may be useful +in some cases, like if you need to write PNG files extremely fast and +are willing to give up some compression, or if you want to get the +maximum possible compression at the expense of slower writing. If you +have no special needs in this area, let the library do what it wants by +not calling this function at all, as it has been tuned to deliver a good +speed/compression ratio. The second parameter to png_set_filter() is +the filter method, for which the only valid values are 0 (as of the +July 1999 PNG specification, version 1.2) or 64 (if you are writing +a PNG datastream that is to be embedded in a MNG datastream). The third +parameter is a flag that indicates which filter type(s) are to be tested +for each scanline. See the PNG specification for details on the specific +filter types. + + + /* turn on or off filtering, and/or choose + specific filters. You can use either a single + PNG_FILTER_VALUE_NAME or the bitwise OR of one + or more PNG_FILTER_NAME masks. */ + png_set_filter(png_ptr, 0, + PNG_FILTER_NONE | PNG_FILTER_VALUE_NONE | + PNG_FILTER_SUB | PNG_FILTER_VALUE_SUB | + PNG_FILTER_UP | PNG_FILTER_VALUE_UP | + PNG_FILTER_AVG | PNG_FILTER_VALUE_AVG | + PNG_FILTER_PAETH | PNG_FILTER_VALUE_PAETH| + PNG_ALL_FILTERS); + +If an application +wants to start and stop using particular filters during compression, +it should start out with all of the filters (to ensure that the previous +row of pixels will be stored in case it's needed later), and then add +and remove them after the start of compression. + +If you are writing a PNG datastream that is to be embedded in a MNG +datastream, the second parameter can be either 0 or 64. + +The png_set_compression_*() functions interface to the zlib compression +library, and should mostly be ignored unless you really know what you are +doing. The only generally useful call is png_set_compression_level() +which changes how much time zlib spends on trying to compress the image +data. See the Compression Library (zlib.h and algorithm.txt, distributed +with zlib) for details on the compression levels. + + /* set the zlib compression level */ + png_set_compression_level(png_ptr, + Z_BEST_COMPRESSION); + + /* set other zlib parameters */ + png_set_compression_mem_level(png_ptr, 8); + png_set_compression_strategy(png_ptr, + Z_DEFAULT_STRATEGY); + png_set_compression_window_bits(png_ptr, 15); + png_set_compression_method(png_ptr, 8); + png_set_compression_buffer_size(png_ptr, 8192) + +extern PNG_EXPORT(void,png_set_zbuf_size) + +Setting the contents of info for output + +You now need to fill in the png_info structure with all the data you +wish to write before the actual image. Note that the only thing you +are allowed to write after the image is the text chunks and the time +chunk (as of PNG Specification 1.2, anyway). See png_write_end() and +the latest PNG specification for more information on that. If you +wish to write them before the image, fill them in now, and flag that +data as being valid. If you want to wait until after the data, don't +fill them until png_write_end(). For all the fields in png_info and +their data types, see png.h. For explanations of what the fields +contain, see the PNG specification. + +Some of the more important parts of the png_info are: + + png_set_IHDR(png_ptr, info_ptr, width, height, + bit_depth, color_type, interlace_type, + compression_type, filter_method) + width - holds the width of the image + in pixels (up to 2^31). + height - holds the height of the image + in pixels (up to 2^31). + bit_depth - holds the bit depth of one of the + image channels. + (valid values are 1, 2, 4, 8, 16 + and depend also on the + color_type. See also significant + bits (sBIT) below). + color_type - describes which color/alpha + channels are present. + PNG_COLOR_TYPE_GRAY + (bit depths 1, 2, 4, 8, 16) + PNG_COLOR_TYPE_GRAY_ALPHA + (bit depths 8, 16) + PNG_COLOR_TYPE_PALETTE + (bit depths 1, 2, 4, 8) + PNG_COLOR_TYPE_RGB + (bit_depths 8, 16) + PNG_COLOR_TYPE_RGB_ALPHA + (bit_depths 8, 16) + + PNG_COLOR_MASK_PALETTE + PNG_COLOR_MASK_COLOR + PNG_COLOR_MASK_ALPHA + + interlace_type - PNG_INTERLACE_NONE or + PNG_INTERLACE_ADAM7 + compression_type - (must be + PNG_COMPRESSION_TYPE_DEFAULT) + filter_method - (must be PNG_FILTER_TYPE_DEFAULT + or, if you are writing a PNG to + be embedded in a MNG datastream, + can also be + PNG_INTRAPIXEL_DIFFERENCING) + +If you call png_set_IHDR(), the call must appear before any of the +other png_set_*() functions, because they might require access to some of +the IHDR settings. The remaining png_set_*() functions can be called +in any order. + +If you wish, you can reset the compression_type, interlace_type, or +filter_method later by calling png_set_IHDR() again; if you do this, the +width, height, bit_depth, and color_type must be the same in each call. + + png_set_PLTE(png_ptr, info_ptr, palette, + num_palette); + palette - the palette for the file + (array of png_color) + num_palette - number of entries in the palette + + png_set_gAMA(png_ptr, info_ptr, gamma); + gamma - the gamma the image was created + at (PNG_INFO_gAMA) + + png_set_sRGB(png_ptr, info_ptr, srgb_intent); + srgb_intent - the rendering intent + (PNG_INFO_sRGB) The presence of + the sRGB chunk means that the pixel + data is in the sRGB color space. + This chunk also implies specific + values of gAMA and cHRM. Rendering + intent is the CSS-1 property that + has been defined by the International + Color Consortium + (http://www.color.org). + It can be one of + PNG_sRGB_INTENT_SATURATION, + PNG_sRGB_INTENT_PERCEPTUAL, + PNG_sRGB_INTENT_ABSOLUTE, or + PNG_sRGB_INTENT_RELATIVE. + + + png_set_sRGB_gAMA_and_cHRM(png_ptr, info_ptr, + srgb_intent); + srgb_intent - the rendering intent + (PNG_INFO_sRGB) The presence of the + sRGB chunk means that the pixel + data is in the sRGB color space. + This function also causes gAMA and + cHRM chunks with the specific values + that are consistent with sRGB to be + written. + + png_set_iCCP(png_ptr, info_ptr, name, compression_type, + profile, proflen); + name - The profile name. + compression - The compression type; always + PNG_COMPRESSION_TYPE_BASE for PNG 1.0. + You may give NULL to this argument to + ignore it. + profile - International Color Consortium color + profile data. May contain NULs. + proflen - length of profile data in bytes. + + png_set_sBIT(png_ptr, info_ptr, sig_bit); + sig_bit - the number of significant bits for + (PNG_INFO_sBIT) each of the gray, red, + green, and blue channels, whichever are + appropriate for the given color type + (png_color_16) + + png_set_tRNS(png_ptr, info_ptr, trans_alpha, + num_trans, trans_color); + trans_alpha - array of alpha (transparency) + entries for palette (PNG_INFO_tRNS) + trans_color - graylevel or color sample values + (in order red, green, blue) of the + single transparent color for + non-paletted images (PNG_INFO_tRNS) + num_trans - number of transparent entries + (PNG_INFO_tRNS) + + png_set_hIST(png_ptr, info_ptr, hist); + (PNG_INFO_hIST) + hist - histogram of palette (array of + png_uint_16) + + png_set_tIME(png_ptr, info_ptr, mod_time); + mod_time - time image was last modified + (PNG_VALID_tIME) + + png_set_bKGD(png_ptr, info_ptr, background); + background - background color (PNG_VALID_bKGD) + + png_set_text(png_ptr, info_ptr, text_ptr, num_text); + text_ptr - array of png_text holding image + comments + text_ptr[i].compression - type of compression used + on "text" PNG_TEXT_COMPRESSION_NONE + PNG_TEXT_COMPRESSION_zTXt + PNG_ITXT_COMPRESSION_NONE + PNG_ITXT_COMPRESSION_zTXt + text_ptr[i].key - keyword for comment. Must contain + 1-79 characters. + text_ptr[i].text - text comments for current + keyword. Can be NULL or empty. + text_ptr[i].text_length - length of text string, + after decompression, 0 for iTXt + text_ptr[i].itxt_length - length of itxt string, + after decompression, 0 for tEXt/zTXt + text_ptr[i].lang - language of comment (NULL or + empty for unknown). + text_ptr[i].translated_keyword - keyword in UTF-8 (NULL + or empty for unknown). + Note that the itxt_length, lang, and lang_key + members of the text_ptr structure only exist + when the library is built with iTXt chunk support. + + num_text - number of comments + + png_set_sPLT(png_ptr, info_ptr, &palette_ptr, + num_spalettes); + palette_ptr - array of png_sPLT_struct structures + to be added to the list of palettes + in the info structure. + num_spalettes - number of palette structures to be + added. + + png_set_oFFs(png_ptr, info_ptr, offset_x, offset_y, + unit_type); + offset_x - positive offset from the left + edge of the screen + offset_y - positive offset from the top + edge of the screen + unit_type - PNG_OFFSET_PIXEL, PNG_OFFSET_MICROMETER + + png_set_pHYs(png_ptr, info_ptr, res_x, res_y, + unit_type); + res_x - pixels/unit physical resolution + in x direction + res_y - pixels/unit physical resolution + in y direction + unit_type - PNG_RESOLUTION_UNKNOWN, + PNG_RESOLUTION_METER + + png_set_sCAL(png_ptr, info_ptr, unit, width, height) + unit - physical scale units (an integer) + width - width of a pixel in physical scale units + height - height of a pixel in physical scale units + (width and height are doubles) + + png_set_sCAL_s(png_ptr, info_ptr, unit, width, height) + unit - physical scale units (an integer) + width - width of a pixel in physical scale units + height - height of a pixel in physical scale units + (width and height are strings like "2.54") + + png_set_unknown_chunks(png_ptr, info_ptr, &unknowns, + num_unknowns) + unknowns - array of png_unknown_chunk + structures holding unknown chunks + unknowns[i].name - name of unknown chunk + unknowns[i].data - data of unknown chunk + unknowns[i].size - size of unknown chunk's data + unknowns[i].location - position to write chunk in file + 0: do not write chunk + PNG_HAVE_IHDR: before PLTE + PNG_HAVE_PLTE: before IDAT + PNG_AFTER_IDAT: after IDAT + +The "location" member is set automatically according to +what part of the output file has already been written. +You can change its value after calling png_set_unknown_chunks() +as demonstrated in pngtest.c. Within each of the "locations", +the chunks are sequenced according to their position in the +structure (that is, the value of "i", which is the order in which +the chunk was either read from the input file or defined with +png_set_unknown_chunks). + +A quick word about text and num_text. text is an array of png_text +structures. num_text is the number of valid structures in the array. +Each png_text structure holds a language code, a keyword, a text value, +and a compression type. + +The compression types have the same valid numbers as the compression +types of the image data. Currently, the only valid number is zero. +However, you can store text either compressed or uncompressed, unlike +images, which always have to be compressed. So if you don't want the +text compressed, set the compression type to PNG_TEXT_COMPRESSION_NONE. +Because tEXt and zTXt chunks don't have a language field, if you +specify PNG_TEXT_COMPRESSION_NONE or PNG_TEXT_COMPRESSION_zTXt +any language code or translated keyword will not be written out. + +Until text gets around 1000 bytes, it is not worth compressing it. +After the text has been written out to the file, the compression type +is set to PNG_TEXT_COMPRESSION_NONE_WR or PNG_TEXT_COMPRESSION_zTXt_WR, +so that it isn't written out again at the end (in case you are calling +png_write_end() with the same struct. + +The keywords that are given in the PNG Specification are: + + Title Short (one line) title or + caption for image + Author Name of image's creator + Description Description of image (possibly long) + Copyright Copyright notice + Creation Time Time of original image creation + (usually RFC 1123 format, see below) + Software Software used to create the image + Disclaimer Legal disclaimer + Warning Warning of nature of content + Source Device used to create the image + Comment Miscellaneous comment; conversion + from other image format + +The keyword-text pairs work like this. Keywords should be short +simple descriptions of what the comment is about. Some typical +keywords are found in the PNG specification, as is some recommendations +on keywords. You can repeat keywords in a file. You can even write +some text before the image and some after. For example, you may want +to put a description of the image before the image, but leave the +disclaimer until after, so viewers working over modem connections +don't have to wait for the disclaimer to go over the modem before +they start seeing the image. Finally, keywords should be full +words, not abbreviations. Keywords and text are in the ISO 8859-1 +(Latin-1) character set (a superset of regular ASCII) and can not +contain NUL characters, and should not contain control or other +unprintable characters. To make the comments widely readable, stick +with basic ASCII, and avoid machine specific character set extensions +like the IBM-PC character set. The keyword must be present, but +you can leave off the text string on non-compressed pairs. +Compressed pairs must have a text string, as only the text string +is compressed anyway, so the compression would be meaningless. + +PNG supports modification time via the png_time structure. Two +conversion routines are provided, png_convert_from_time_t() for +time_t and png_convert_from_struct_tm() for struct tm. The +time_t routine uses gmtime(). You don't have to use either of +these, but if you wish to fill in the png_time structure directly, +you should provide the time in universal time (GMT) if possible +instead of your local time. Note that the year number is the full +year (e.g. 1998, rather than 98 - PNG is year 2000 compliant!), and +that months start with 1. + +If you want to store the time of the original image creation, you should +use a plain tEXt chunk with the "Creation Time" keyword. This is +necessary because the "creation time" of a PNG image is somewhat vague, +depending on whether you mean the PNG file, the time the image was +created in a non-PNG format, a still photo from which the image was +scanned, or possibly the subject matter itself. In order to facilitate +machine-readable dates, it is recommended that the "Creation Time" +tEXt chunk use RFC 1123 format dates (e.g. "22 May 1997 18:07:10 GMT"), +although this isn't a requirement. Unlike the tIME chunk, the +"Creation Time" tEXt chunk is not expected to be automatically changed +by the software. To facilitate the use of RFC 1123 dates, a function +png_convert_to_rfc1123(png_timep) is provided to convert from PNG +time to an RFC 1123 format string. + +Writing unknown chunks + +You can use the png_set_unknown_chunks function to queue up chunks +for writing. You give it a chunk name, raw data, and a size; that's +all there is to it. The chunks will be written by the next following +png_write_info_before_PLTE, png_write_info, or png_write_end function. +Any chunks previously read into the info structure's unknown-chunk +list will also be written out in a sequence that satisfies the PNG +specification's ordering rules. + +The high-level write interface + +At this point there are two ways to proceed; through the high-level +write interface, or through a sequence of low-level write operations. +You can use the high-level interface if your image data is present +in the info structure. All defined output +transformations are permitted, enabled by the following masks. + + PNG_TRANSFORM_IDENTITY No transformation + PNG_TRANSFORM_PACKING Pack 1, 2 and 4-bit samples + PNG_TRANSFORM_PACKSWAP Change order of packed + pixels to LSB first + PNG_TRANSFORM_INVERT_MONO Invert monochrome images + PNG_TRANSFORM_SHIFT Normalize pixels to the + sBIT depth + PNG_TRANSFORM_BGR Flip RGB to BGR, RGBA + to BGRA + PNG_TRANSFORM_SWAP_ALPHA Flip RGBA to ARGB or GA + to AG + PNG_TRANSFORM_INVERT_ALPHA Change alpha from opacity + to transparency + PNG_TRANSFORM_SWAP_ENDIAN Byte-swap 16-bit samples + PNG_TRANSFORM_STRIP_FILLER Strip out filler + bytes (deprecated). + PNG_TRANSFORM_STRIP_FILLER_BEFORE Strip out leading + filler bytes + PNG_TRANSFORM_STRIP_FILLER_AFTER Strip out trailing + filler bytes + +If you have valid image data in the info structure (you can use +png_set_rows() to put image data in the info structure), simply do this: + + png_write_png(png_ptr, info_ptr, png_transforms, NULL) + +where png_transforms is an integer containing the bitwise OR of some set of +transformation flags. This call is equivalent to png_write_info(), +followed the set of transformations indicated by the transform mask, +then png_write_image(), and finally png_write_end(). + +(The final parameter of this call is not yet used. Someday it might point +to transformation parameters required by some future output transform.) + +You must use png_transforms and not call any png_set_transform() functions +when you use png_write_png(). + +The low-level write interface + +If you are going the low-level route instead, you are now ready to +write all the file information up to the actual image data. You do +this with a call to png_write_info(). + + png_write_info(png_ptr, info_ptr); + +Note that there is one transformation you may need to do before +png_write_info(). In PNG files, the alpha channel in an image is the +level of opacity. If your data is supplied as a level of transparency, +you can invert the alpha channel before you write it, so that 0 is +fully transparent and 255 (in 8-bit or paletted images) or 65535 +(in 16-bit images) is fully opaque, with + + png_set_invert_alpha(png_ptr); + +This must appear before png_write_info() instead of later with the +other transformations because in the case of paletted images the tRNS +chunk data has to be inverted before the tRNS chunk is written. If +your image is not a paletted image, the tRNS data (which in such cases +represents a single color to be rendered as transparent) won't need to +be changed, and you can safely do this transformation after your +png_write_info() call. + +If you need to write a private chunk that you want to appear before +the PLTE chunk when PLTE is present, you can write the PNG info in +two steps, and insert code to write your own chunk between them: + + png_write_info_before_PLTE(png_ptr, info_ptr); + png_set_unknown_chunks(png_ptr, info_ptr, ...); + png_write_info(png_ptr, info_ptr); + +After you've written the file information, you can set up the library +to handle any special transformations of the image data. The various +ways to transform the data will be described in the order that they +should occur. This is important, as some of these change the color +type and/or bit depth of the data, and some others only work on +certain color types and bit depths. Even though each transformation +checks to see if it has data that it can do something with, you should +make sure to only enable a transformation if it will be valid for the +data. For example, don't swap red and blue on grayscale data. + +PNG files store RGB pixels packed into 3 or 6 bytes. This code tells +the library to strip input data that has 4 or 8 bytes per pixel down +to 3 or 6 bytes (or strip 2 or 4-byte grayscale+filler data to 1 or 2 +bytes per pixel). + + png_set_filler(png_ptr, 0, PNG_FILLER_BEFORE); + +where the 0 is unused, and the location is either PNG_FILLER_BEFORE or +PNG_FILLER_AFTER, depending upon whether the filler byte in the pixel +is stored XRGB or RGBX. + +PNG files pack pixels of bit depths 1, 2, and 4 into bytes as small as +they can, resulting in, for example, 8 pixels per byte for 1 bit files. +If the data is supplied at 1 pixel per byte, use this code, which will +correctly pack the pixels into a single byte: + + png_set_packing(png_ptr); + +PNG files reduce possible bit depths to 1, 2, 4, 8, and 16. If your +data is of another bit depth, you can write an sBIT chunk into the +file so that decoders can recover the original data if desired. + + /* Set the true bit depth of the image data */ + if (color_type & PNG_COLOR_MASK_COLOR) + { + sig_bit.red = true_bit_depth; + sig_bit.green = true_bit_depth; + sig_bit.blue = true_bit_depth; + } + else + { + sig_bit.gray = true_bit_depth; + } + if (color_type & PNG_COLOR_MASK_ALPHA) + { + sig_bit.alpha = true_bit_depth; + } + + png_set_sBIT(png_ptr, info_ptr, &sig_bit); + +If the data is stored in the row buffer in a bit depth other than +one supported by PNG (e.g. 3 bit data in the range 0-7 for a 4-bit PNG), +this will scale the values to appear to be the correct bit depth as +is required by PNG. + + png_set_shift(png_ptr, &sig_bit); + +PNG files store 16 bit pixels in network byte order (big-endian, +ie. most significant bits first). This code would be used if they are +supplied the other way (little-endian, i.e. least significant bits +first, the way PCs store them): + + if (bit_depth > 8) + png_set_swap(png_ptr); + +If you are using packed-pixel images (1, 2, or 4 bits/pixel), and you +need to change the order the pixels are packed into bytes, you can use: + + if (bit_depth < 8) + png_set_packswap(png_ptr); + +PNG files store 3 color pixels in red, green, blue order. This code +would be used if they are supplied as blue, green, red: + + png_set_bgr(png_ptr); + +PNG files describe monochrome as black being zero and white being +one. This code would be used if the pixels are supplied with this reversed +(black being one and white being zero): + + png_set_invert_mono(png_ptr); + +Finally, you can write your own transformation function if none of +the existing ones meets your needs. This is done by setting a callback +with + + png_set_write_user_transform_fn(png_ptr, + write_transform_fn); + +You must supply the function + + void write_transform_fn(png_ptr ptr, row_info_ptr + row_info, png_bytep data) + +See pngtest.c for a working example. Your function will be called +before any of the other transformations are processed. + +You can also set up a pointer to a user structure for use by your +callback function. + + png_set_user_transform_info(png_ptr, user_ptr, 0, 0); + +The user_channels and user_depth parameters of this function are ignored +when writing; you can set them to zero as shown. + +You can retrieve the pointer via the function png_get_user_transform_ptr(). +For example: + + voidp write_user_transform_ptr = + png_get_user_transform_ptr(png_ptr); + +It is possible to have libpng flush any pending output, either manually, +or automatically after a certain number of lines have been written. To +flush the output stream a single time call: + + png_write_flush(png_ptr); + +and to have libpng flush the output stream periodically after a certain +number of scanlines have been written, call: + + png_set_flush(png_ptr, nrows); + +Note that the distance between rows is from the last time png_write_flush() +was called, or the first row of the image if it has never been called. +So if you write 50 lines, and then png_set_flush 25, it will flush the +output on the next scanline, and every 25 lines thereafter, unless +png_write_flush() is called before 25 more lines have been written. +If nrows is too small (less than about 10 lines for a 640 pixel wide +RGB image) the image compression may decrease noticeably (although this +may be acceptable for real-time applications). Infrequent flushing will +only degrade the compression performance by a few percent over images +that do not use flushing. + +Writing the image data + +That's it for the transformations. Now you can write the image data. +The simplest way to do this is in one function call. If you have the +whole image in memory, you can just call png_write_image() and libpng +will write the image. You will need to pass in an array of pointers to +each row. This function automatically handles interlacing, so you don't +need to call png_set_interlace_handling() or call this function multiple +times, or any of that other stuff necessary with png_write_rows(). + + png_write_image(png_ptr, row_pointers); + +where row_pointers is: + + png_byte *row_pointers[height]; + +You can point to void or char or whatever you use for pixels. + +If you don't want to write the whole image at once, you can +use png_write_rows() instead. If the file is not interlaced, +this is simple: + + png_write_rows(png_ptr, row_pointers, + number_of_rows); + +row_pointers is the same as in the png_write_image() call. + +If you are just writing one row at a time, you can do this with +a single row_pointer instead of an array of row_pointers: + + png_bytep row_pointer = row; + + png_write_row(png_ptr, row_pointer); + +When the file is interlaced, things can get a good deal more complicated. +The only currently (as of the PNG Specification version 1.2, dated July +1999) defined interlacing scheme for PNG files is the "Adam7" interlace +scheme, that breaks down an image into seven smaller images of varying +size. libpng will build these images for you, or you can do them +yourself. If you want to build them yourself, see the PNG specification +for details of which pixels to write when. + +If you don't want libpng to handle the interlacing details, just +use png_set_interlace_handling() and call png_write_rows() the +correct number of times to write all seven sub-images. + +If you want libpng to build the sub-images, call this before you start +writing any rows: + + number_of_passes = + png_set_interlace_handling(png_ptr); + +This will return the number of passes needed. Currently, this is seven, +but may change if another interlace type is added. + +Then write the complete image number_of_passes times. + + png_write_rows(png_ptr, row_pointers, + number_of_rows); + +As some of these rows are not used, and thus return immediately, you may +want to read about interlacing in the PNG specification, and only update +the rows that are actually used. + +Finishing a sequential write + +After you are finished writing the image, you should finish writing +the file. If you are interested in writing comments or time, you should +pass an appropriately filled png_info pointer. If you are not interested, +you can pass NULL. + + png_write_end(png_ptr, info_ptr); + +When you are done, you can free all memory used by libpng like this: + + png_destroy_write_struct(&png_ptr, &info_ptr); + +It is also possible to individually free the info_ptr members that +point to libpng-allocated storage with the following function: + + png_free_data(png_ptr, info_ptr, mask, seq) + mask - identifies data to be freed, a mask + containing the bitwise OR of one or + more of + PNG_FREE_PLTE, PNG_FREE_TRNS, + PNG_FREE_HIST, PNG_FREE_ICCP, + PNG_FREE_PCAL, PNG_FREE_ROWS, + PNG_FREE_SCAL, PNG_FREE_SPLT, + PNG_FREE_TEXT, PNG_FREE_UNKN, + or simply PNG_FREE_ALL + seq - sequence number of item to be freed + (-1 for all items) + +This function may be safely called when the relevant storage has +already been freed, or has not yet been allocated, or was allocated +by the user and not by libpng, and will in those cases do nothing. +The "seq" parameter is ignored if only one item of the selected data +type, such as PLTE, is allowed. If "seq" is not -1, and multiple items +are allowed for the data type identified in the mask, such as text or +sPLT, only the n'th item in the structure is freed, where n is "seq". + +If you allocated data such as a palette that you passed in to libpng +with png_set_*, you must not free it until just before the call to +png_destroy_write_struct(). + +The default behavior is only to free data that was allocated internally +by libpng. This can be changed, so that libpng will not free the data, +or so that it will free data that was allocated by the user with png_malloc() +or png_zalloc() and passed in via a png_set_*() function, with + + png_data_freer(png_ptr, info_ptr, freer, mask) + mask - which data elements are affected + same choices as in png_free_data() + freer - one of + PNG_DESTROY_WILL_FREE_DATA + PNG_SET_WILL_FREE_DATA + PNG_USER_WILL_FREE_DATA + +For example, to transfer responsibility for some data from a read structure +to a write structure, you could use + + png_data_freer(read_ptr, read_info_ptr, + PNG_USER_WILL_FREE_DATA, + PNG_FREE_PLTE|PNG_FREE_tRNS|PNG_FREE_hIST) + png_data_freer(write_ptr, write_info_ptr, + PNG_DESTROY_WILL_FREE_DATA, + PNG_FREE_PLTE|PNG_FREE_tRNS|PNG_FREE_hIST) + +thereby briefly reassigning responsibility for freeing to the user but +immediately afterwards reassigning it once more to the write_destroy +function. Having done this, it would then be safe to destroy the read +structure and continue to use the PLTE, tRNS, and hIST data in the write +structure. + +This function only affects data that has already been allocated. +You can call this function before calling after the png_set_*() functions +to control whether the user or png_destroy_*() is supposed to free the data. +When the user assumes responsibility for libpng-allocated data, the +application must use +png_free() to free it, and when the user transfers responsibility to libpng +for data that the user has allocated, the user must have used png_malloc() +or png_zalloc() to allocate it. + +If you allocated text_ptr.text, text_ptr.lang, and text_ptr.translated_keyword +separately, do not transfer responsibility for freeing text_ptr to libpng, +because when libpng fills a png_text structure it combines these members with +the key member, and png_free_data() will free only text_ptr.key. Similarly, +if you transfer responsibility for free'ing text_ptr from libpng to your +application, your application must not separately free those members. +For a more compact example of writing a PNG image, see the file example.c. + +V. Modifying/Customizing libpng: + +There are two issues here. The first is changing how libpng does +standard things like memory allocation, input/output, and error handling. +The second deals with more complicated things like adding new chunks, +adding new transformations, and generally changing how libpng works. +Both of those are compile-time issues; that is, they are generally +determined at the time the code is written, and there is rarely a need +to provide the user with a means of changing them. + +Memory allocation, input/output, and error handling + +All of the memory allocation, input/output, and error handling in libpng +goes through callbacks that are user-settable. The default routines are +in pngmem.c, pngrio.c, pngwio.c, and pngerror.c, respectively. To change +these functions, call the appropriate png_set_*_fn() function. + +Memory allocation is done through the functions png_malloc(), png_calloc(), +and png_free(). These currently just call the standard C functions. +png_calloc() calls png_malloc() and then png_memset() to clear the newly +allocated memory to zero. If your pointers can't access more then 64K +at a time, you will want to set MAXSEG_64K in zlib.h. Since it is +unlikely that the method of handling memory allocation on a platform +will change between applications, these functions must be modified in +the library at compile time. If you prefer to use a different method +of allocating and freeing data, you can use png_create_read_struct_2() or +png_create_write_struct_2() to register your own functions as described +above. These functions also provide a void pointer that can be retrieved +via + + mem_ptr=png_get_mem_ptr(png_ptr); + +Your replacement memory functions must have prototypes as follows: + + png_voidp malloc_fn(png_structp png_ptr, + png_alloc_size_t size); + void free_fn(png_structp png_ptr, png_voidp ptr); + +Your malloc_fn() must return NULL in case of failure. The png_malloc() +function will normally call png_error() if it receives a NULL from the +system memory allocator or from your replacement malloc_fn(). + +Your free_fn() will never be called with a NULL ptr, since libpng's +png_free() checks for NULL before calling free_fn(). + +Input/Output in libpng is done through png_read() and png_write(), +which currently just call fread() and fwrite(). The FILE * is stored in +png_struct and is initialized via png_init_io(). If you wish to change +the method of I/O, the library supplies callbacks that you can set +through the function png_set_read_fn() and png_set_write_fn() at run +time, instead of calling the png_init_io() function. These functions +also provide a void pointer that can be retrieved via the function +png_get_io_ptr(). For example: + + png_set_read_fn(png_structp read_ptr, + voidp read_io_ptr, png_rw_ptr read_data_fn) + + png_set_write_fn(png_structp write_ptr, + voidp write_io_ptr, png_rw_ptr write_data_fn, + png_flush_ptr output_flush_fn); + + voidp read_io_ptr = png_get_io_ptr(read_ptr); + voidp write_io_ptr = png_get_io_ptr(write_ptr); + +The replacement I/O functions must have prototypes as follows: + + void user_read_data(png_structp png_ptr, + png_bytep data, png_size_t length); + void user_write_data(png_structp png_ptr, + png_bytep data, png_size_t length); + void user_flush_data(png_structp png_ptr); + +The user_read_data() function is responsible for detecting and +handling end-of-data errors. + +Supplying NULL for the read, write, or flush functions sets them back +to using the default C stream functions, which expect the io_ptr to +point to a standard *FILE structure. It is probably a mistake +to use NULL for one of write_data_fn and output_flush_fn but not both +of them, unless you have built libpng with PNG_NO_WRITE_FLUSH defined. +It is an error to read from a write stream, and vice versa. + +Error handling in libpng is done through png_error() and png_warning(). +Errors handled through png_error() are fatal, meaning that png_error() +should never return to its caller. Currently, this is handled via +setjmp() and longjmp() (unless you have compiled libpng with +PNG_NO_SETJMP, in which case it is handled via PNG_ABORT()), +but you could change this to do things like exit() if you should wish, +as long as your function does not return. + +On non-fatal errors, png_warning() is called +to print a warning message, and then control returns to the calling code. +By default png_error() and png_warning() print a message on stderr via +fprintf() unless the library is compiled with PNG_NO_CONSOLE_IO defined +(because you don't want the messages) or PNG_NO_STDIO defined (because +fprintf() isn't available). If you wish to change the behavior of the error +functions, you will need to set up your own message callbacks. These +functions are normally supplied at the time that the png_struct is created. +It is also possible to redirect errors and warnings to your own replacement +functions after png_create_*_struct() has been called by calling: + + png_set_error_fn(png_structp png_ptr, + png_voidp error_ptr, png_error_ptr error_fn, + png_error_ptr warning_fn); + + png_voidp error_ptr = png_get_error_ptr(png_ptr); + +If NULL is supplied for either error_fn or warning_fn, then the libpng +default function will be used, calling fprintf() and/or longjmp() if a +problem is encountered. The replacement error functions should have +parameters as follows: + + void user_error_fn(png_structp png_ptr, + png_const_charp error_msg); + void user_warning_fn(png_structp png_ptr, + png_const_charp warning_msg); + +The motivation behind using setjmp() and longjmp() is the C++ throw and +catch exception handling methods. This makes the code much easier to write, +as there is no need to check every return code of every function call. +However, there are some uncertainties about the status of local variables +after a longjmp, so the user may want to be careful about doing anything +after setjmp returns non-zero besides returning itself. Consult your +compiler documentation for more details. For an alternative approach, you +may wish to use the "cexcept" facility (see http://cexcept.sourceforge.net). + +Custom chunks + +If you need to read or write custom chunks, you may need to get deeper +into the libpng code. The library now has mechanisms for storing +and writing chunks of unknown type; you can even declare callbacks +for custom chunks. However, this may not be good enough if the +library code itself needs to know about interactions between your +chunk and existing `intrinsic' chunks. + +If you need to write a new intrinsic chunk, first read the PNG +specification. Acquire a first level of understanding of how it works. +Pay particular attention to the sections that describe chunk names, +and look at how other chunks were designed, so you can do things +similarly. Second, check out the sections of libpng that read and +write chunks. Try to find a chunk that is similar to yours and use +it as a template. More details can be found in the comments inside +the code. It is best to handle unknown chunks in a generic method, +via callback functions, instead of by modifying libpng functions. + +If you wish to write your own transformation for the data, look through +the part of the code that does the transformations, and check out some of +the simpler ones to get an idea of how they work. Try to find a similar +transformation to the one you want to add and copy off of it. More details +can be found in the comments inside the code itself. + +Configuring for 16 bit platforms + +You will want to look into zconf.h to tell zlib (and thus libpng) that +it cannot allocate more then 64K at a time. Even if you can, the memory +won't be accessible. So limit zlib and libpng to 64K by defining MAXSEG_64K. + +Configuring for DOS + +For DOS users who only have access to the lower 640K, you will +have to limit zlib's memory usage via a png_set_compression_mem_level() +call. See zlib.h or zconf.h in the zlib library for more information. + +Configuring for Medium Model + +Libpng's support for medium model has been tested on most of the popular +compilers. Make sure MAXSEG_64K gets defined, USE_FAR_KEYWORD gets +defined, and FAR gets defined to far in pngconf.h, and you should be +all set. Everything in the library (except for zlib's structure) is +expecting far data. You must use the typedefs with the p or pp on +the end for pointers (or at least look at them and be careful). Make +note that the rows of data are defined as png_bytepp, which is an +unsigned char far * far *. + +Configuring for gui/windowing platforms: + +You will need to write new error and warning functions that use the GUI +interface, as described previously, and set them to be the error and +warning functions at the time that png_create_*_struct() is called, +in order to have them available during the structure initialization. +They can be changed later via png_set_error_fn(). On some compilers, +you may also have to change the memory allocators (png_malloc, etc.). + +Configuring for compiler xxx: + +All includes for libpng are in pngconf.h. If you need to add, change +or delete an include, this is the place to do it. +The includes that are not needed outside libpng are placed in pngpriv.h, +which is only used by the routines inside libpng itself. +The files in libpng proper only include pngpriv.h and png.h, which +in turn includes pngconf.h. + +Configuring zlib: + +There are special functions to configure the compression. Perhaps the +most useful one changes the compression level, which currently uses +input compression values in the range 0 - 9. The library normally +uses the default compression level (Z_DEFAULT_COMPRESSION = 6). Tests +have shown that for a large majority of images, compression values in +the range 3-6 compress nearly as well as higher levels, and do so much +faster. For online applications it may be desirable to have maximum speed +(Z_BEST_SPEED = 1). With versions of zlib after v0.99, you can also +specify no compression (Z_NO_COMPRESSION = 0), but this would create +files larger than just storing the raw bitmap. You can specify the +compression level by calling: + + png_set_compression_level(png_ptr, level); + +Another useful one is to reduce the memory level used by the library. +The memory level defaults to 8, but it can be lowered if you are +short on memory (running DOS, for example, where you only have 640K). +Note that the memory level does have an effect on compression; among +other things, lower levels will result in sections of incompressible +data being emitted in smaller stored blocks, with a correspondingly +larger relative overhead of up to 15% in the worst case. + + png_set_compression_mem_level(png_ptr, level); + +The other functions are for configuring zlib. They are not recommended +for normal use and may result in writing an invalid PNG file. See +zlib.h for more information on what these mean. + + png_set_compression_strategy(png_ptr, + strategy); + png_set_compression_window_bits(png_ptr, + window_bits); + png_set_compression_method(png_ptr, method); + png_set_compression_buffer_size(png_ptr, size); + +Controlling row filtering + +If you want to control whether libpng uses filtering or not, which +filters are used, and how it goes about picking row filters, you +can call one of these functions. The selection and configuration +of row filters can have a significant impact on the size and +encoding speed and a somewhat lesser impact on the decoding speed +of an image. Filtering is enabled by default for RGB and grayscale +images (with and without alpha), but not for paletted images nor +for any images with bit depths less than 8 bits/pixel. + +The 'method' parameter sets the main filtering method, which is +currently only '0' in the PNG 1.2 specification. The 'filters' +parameter sets which filter(s), if any, should be used for each +scanline. Possible values are PNG_ALL_FILTERS and PNG_NO_FILTERS +to turn filtering on and off, respectively. + +Individual filter types are PNG_FILTER_NONE, PNG_FILTER_SUB, +PNG_FILTER_UP, PNG_FILTER_AVG, PNG_FILTER_PAETH, which can be bitwise +ORed together with '|' to specify one or more filters to use. +These filters are described in more detail in the PNG specification. +If you intend to change the filter type during the course of writing +the image, you should start with flags set for all of the filters +you intend to use so that libpng can initialize its internal +structures appropriately for all of the filter types. (Note that this +means the first row must always be adaptively filtered, because libpng +currently does not allocate the filter buffers until png_write_row() +is called for the first time.) + + filters = PNG_FILTER_NONE | PNG_FILTER_SUB + PNG_FILTER_UP | PNG_FILTER_AVG | + PNG_FILTER_PAETH | PNG_ALL_FILTERS; + + png_set_filter(png_ptr, PNG_FILTER_TYPE_BASE, + filters); + The second parameter can also be + PNG_INTRAPIXEL_DIFFERENCING if you are + writing a PNG to be embedded in a MNG + datastream. This parameter must be the + same as the value of filter_method used + in png_set_IHDR(). + +It is also possible to influence how libpng chooses from among the +available filters. This is done in one or both of two ways - by +telling it how important it is to keep the same filter for successive +rows, and by telling it the relative computational costs of the filters. + + double weights[3] = {1.5, 1.3, 1.1}, + costs[PNG_FILTER_VALUE_LAST] = + {1.0, 1.3, 1.3, 1.5, 1.7}; + + png_set_filter_heuristics(png_ptr, + PNG_FILTER_HEURISTIC_WEIGHTED, 3, + weights, costs); + +The weights are multiplying factors that indicate to libpng that the +row filter should be the same for successive rows unless another row filter +is that many times better than the previous filter. In the above example, +if the previous 3 filters were SUB, SUB, NONE, the SUB filter could have a +"sum of absolute differences" 1.5 x 1.3 times higher than other filters +and still be chosen, while the NONE filter could have a sum 1.1 times +higher than other filters and still be chosen. Unspecified weights are +taken to be 1.0, and the specified weights should probably be declining +like those above in order to emphasize recent filters over older filters. + +The filter costs specify for each filter type a relative decoding cost +to be considered when selecting row filters. This means that filters +with higher costs are less likely to be chosen over filters with lower +costs, unless their "sum of absolute differences" is that much smaller. +The costs do not necessarily reflect the exact computational speeds of +the various filters, since this would unduly influence the final image +size. + +Note that the numbers above were invented purely for this example and +are given only to help explain the function usage. Little testing has +been done to find optimum values for either the costs or the weights. + +Removing unwanted object code + +There are a bunch of #define's in pngconf.h that control what parts of +libpng are compiled. All the defines end in _SUPPORTED. If you are +never going to use a capability, you can change the #define to #undef +before recompiling libpng and save yourself code and data space, or +you can turn off individual capabilities with defines that begin with +PNG_NO_. + +You can also turn all of the transforms and ancillary chunk capabilities +off en masse with compiler directives that define +PNG_NO_READ[or WRITE]_TRANSFORMS, or PNG_NO_READ[or WRITE]_ANCILLARY_CHUNKS, +or all four, +along with directives to turn on any of the capabilities that you do +want. The PNG_NO_READ[or WRITE]_TRANSFORMS directives disable the extra +transformations but still leave the library fully capable of reading +and writing PNG files with all known public chunks. Use of the +PNG_NO_READ[or WRITE]_ANCILLARY_CHUNKS directive produces a library +that is incapable of reading or writing ancillary chunks. If you are +not using the progressive reading capability, you can turn that off +with PNG_NO_PROGRESSIVE_READ (don't confuse this with the INTERLACING +capability, which you'll still have). + +All the reading and writing specific code are in separate files, so the +linker should only grab the files it needs. However, if you want to +make sure, or if you are building a stand alone library, all the +reading files start with pngr and all the writing files start with +pngw. The files that don't match either (like png.c, pngtrans.c, etc.) +are used for both reading and writing, and always need to be included. +The progressive reader is in pngpread.c + +If you are creating or distributing a dynamically linked library (a .so +or DLL file), you should not remove or disable any parts of the library, +as this will cause applications linked with different versions of the +library to fail if they call functions not available in your library. +The size of the library itself should not be an issue, because only +those sections that are actually used will be loaded into memory. + +Requesting debug printout + +The macro definition PNG_DEBUG can be used to request debugging +printout. Set it to an integer value in the range 0 to 3. Higher +numbers result in increasing amounts of debugging information. The +information is printed to the "stderr" file, unless another file +name is specified in the PNG_DEBUG_FILE macro definition. + +When PNG_DEBUG > 0, the following functions (macros) become available: + + png_debug(level, message) + png_debug1(level, message, p1) + png_debug2(level, message, p1, p2) + +in which "level" is compared to PNG_DEBUG to decide whether to print +the message, "message" is the formatted string to be printed, +and p1 and p2 are parameters that are to be embedded in the string +according to printf-style formatting directives. For example, + + png_debug1(2, "foo=%d\n", foo); + +is expanded to + + if(PNG_DEBUG > 2) + fprintf(PNG_DEBUG_FILE, "foo=%d\n", foo); + +When PNG_DEBUG is defined but is zero, the macros aren't defined, but you +can still use PNG_DEBUG to control your own debugging: + + #ifdef PNG_DEBUG + fprintf(stderr, ... + #endif + +When PNG_DEBUG = 1, the macros are defined, but only png_debug statements +having level = 0 will be printed. There aren't any such statements in +this version of libpng, but if you insert some they will be printed. + +VI. MNG support + +The MNG specification (available at http://www.libpng.org/pub/mng) allows +certain extensions to PNG for PNG images that are embedded in MNG datastreams. +Libpng can support some of these extensions. To enable them, use the +png_permit_mng_features() function: + + feature_set = png_permit_mng_features(png_ptr, mask) + mask is a png_uint_32 containing the bitwise OR of the + features you want to enable. These include + PNG_FLAG_MNG_EMPTY_PLTE + PNG_FLAG_MNG_FILTER_64 + PNG_ALL_MNG_FEATURES + feature_set is a png_uint_32 that is the bitwise AND of + your mask with the set of MNG features that is + supported by the version of libpng that you are using. + +It is an error to use this function when reading or writing a standalone +PNG file with the PNG 8-byte signature. The PNG datastream must be wrapped +in a MNG datastream. As a minimum, it must have the MNG 8-byte signature +and the MHDR and MEND chunks. Libpng does not provide support for these +or any other MNG chunks; your application must provide its own support for +them. You may wish to consider using libmng (available at +http://www.libmng.com) instead. + +VII. Changes to Libpng from version 0.88 + +It should be noted that versions of libpng later than 0.96 are not +distributed by the original libpng author, Guy Schalnat, nor by +Andreas Dilger, who had taken over from Guy during 1996 and 1997, and +distributed versions 0.89 through 0.96, but rather by another member +of the original PNG Group, Glenn Randers-Pehrson. Guy and Andreas are +still alive and well, but they have moved on to other things. + +The old libpng functions png_read_init(), png_write_init(), +png_info_init(), png_read_destroy(), and png_write_destroy() have been +moved to PNG_INTERNAL in version 0.95 to discourage their use. These +functions will be removed from libpng version 2.0.0. + +The preferred method of creating and initializing the libpng structures is +via the png_create_read_struct(), png_create_write_struct(), and +png_create_info_struct() because they isolate the size of the structures +from the application, allow version error checking, and also allow the +use of custom error handling routines during the initialization, which +the old functions do not. The functions png_read_destroy() and +png_write_destroy() do not actually free the memory that libpng +allocated for these structs, but just reset the data structures, so they +can be used instead of png_destroy_read_struct() and +png_destroy_write_struct() if you feel there is too much system overhead +allocating and freeing the png_struct for each image read. + +Setting the error callbacks via png_set_message_fn() before +png_read_init() as was suggested in libpng-0.88 is no longer supported +because this caused applications that do not use custom error functions +to fail if the png_ptr was not initialized to zero. It is still possible +to set the error callbacks AFTER png_read_init(), or to change them with +png_set_error_fn(), which is essentially the same function, but with a new +name to force compilation errors with applications that try to use the old +method. + +Starting with version 1.0.7, you can find out which version of the library +you are using at run-time: + + png_uint_32 libpng_vn = png_access_version_number(); + +The number libpng_vn is constructed from the major version, minor +version with leading zero, and release number with leading zero, +(e.g., libpng_vn for version 1.0.7 is 10007). + +You can also check which version of png.h you used when compiling your +application: + + png_uint_32 application_vn = PNG_LIBPNG_VER; + +VIII. Changes to Libpng from version 1.0.x to 1.2.x + +Support for user memory management was enabled by default. To +accomplish this, the functions png_create_read_struct_2(), +png_create_write_struct_2(), png_set_mem_fn(), png_get_mem_ptr(), +png_malloc_default(), and png_free_default() were added. + +Support for the iTXt chunk has been enabled by default as of +version 1.2.41. + +Support for certain MNG features was enabled. + +Support for numbered error messages was added. However, we never got +around to actually numbering the error messages. The function +png_set_strip_error_numbers() was added (Note: the prototype for this +function was inadvertently removed from png.h in PNG_NO_ASSEMBLER_CODE +builds of libpng-1.2.15. It was restored in libpng-1.2.36). + +The png_malloc_warn() function was added at libpng-1.2.3. This issues +a png_warning and returns NULL instead of aborting when it fails to +acquire the requested memory allocation. + +Support for setting user limits on image width and height was enabled +by default. The functions png_set_user_limits(), png_get_user_width_max(), +and png_get_user_height_max() were added at libpng-1.2.6. + +The png_set_add_alpha() function was added at libpng-1.2.7. + +The function png_set_expand_gray_1_2_4_to_8() was added at libpng-1.2.9. +Unlike png_set_gray_1_2_4_to_8(), the new function does not expand the +tRNS chunk to alpha. The png_set_gray_1_2_4_to_8() function is +deprecated. + +A number of macro definitions in support of runtime selection of +assembler code features (especially Intel MMX code support) were +added at libpng-1.2.0: + + PNG_ASM_FLAG_MMX_SUPPORT_COMPILED + PNG_ASM_FLAG_MMX_SUPPORT_IN_CPU + PNG_ASM_FLAG_MMX_READ_COMBINE_ROW + PNG_ASM_FLAG_MMX_READ_INTERLACE + PNG_ASM_FLAG_MMX_READ_FILTER_SUB + PNG_ASM_FLAG_MMX_READ_FILTER_UP + PNG_ASM_FLAG_MMX_READ_FILTER_AVG + PNG_ASM_FLAG_MMX_READ_FILTER_PAETH + PNG_ASM_FLAGS_INITIALIZED + PNG_MMX_READ_FLAGS + PNG_MMX_FLAGS + PNG_MMX_WRITE_FLAGS + PNG_MMX_FLAGS + +We added the following functions in support of runtime +selection of assembler code features: + + png_get_mmx_flagmask() + png_set_mmx_thresholds() + png_get_asm_flags() + png_get_mmx_bitdepth_threshold() + png_get_mmx_rowbytes_threshold() + png_set_asm_flags() + +We replaced all of these functions with simple stubs in libpng-1.2.20, +when the Intel assembler code was removed due to a licensing issue. + +These macros are deprecated: + + PNG_READ_TRANSFORMS_NOT_SUPPORTED + PNG_PROGRESSIVE_READ_NOT_SUPPORTED + PNG_NO_SEQUENTIAL_READ_SUPPORTED + PNG_WRITE_TRANSFORMS_NOT_SUPPORTED + PNG_READ_ANCILLARY_CHUNKS_NOT_SUPPORTED + PNG_WRITE_ANCILLARY_CHUNKS_NOT_SUPPORTED + +They have been replaced, respectively, by: + + PNG_NO_READ_TRANSFORMS + PNG_NO_PROGRESSIVE_READ + PNG_NO_SEQUENTIAL_READ + PNG_NO_WRITE_TRANSFORMS + PNG_NO_READ_ANCILLARY_CHUNKS + PNG_NO_WRITE_ANCILLARY_CHUNKS + +PNG_MAX_UINT was replaced with PNG_UINT_31_MAX. It has been +deprecated since libpng-1.0.16 and libpng-1.2.6. + +The function + png_check_sig(sig, num) +was replaced with + !png_sig_cmp(sig, 0, num) +It has been deprecated since libpng-0.90. + +The function + png_set_gray_1_2_4_to_8() +which also expands tRNS to alpha was replaced with + png_set_expand_gray_1_2_4_to_8() +which does not. It has been deprecated since libpng-1.0.18 and 1.2.9. + +IX. Changes to Libpng from version 1.0.x/1.2.x to 1.4.x + +Private libpng prototypes and macro definitions were moved from +png.h and pngconf.h into a new pngpriv.h header file. + +Functions png_set_benign_errors(), png_benign_error(), and +png_chunk_benign_error() were added. + +Support for setting the maximum amount of memory that the application +will allocate for reading chunks was added, as a security measure. +The functions png_set_chunk_cache_max() and png_get_chunk_cache_max() +were added to the library. + +We implemented support for I/O states by adding png_ptr member io_state +and functions png_get_io_chunk_name() and png_get_io_state() in pngget.c + +We added PNG_TRANSFORM_GRAY_TO_RGB to the available high-level +input transforms. + +Checking for and reporting of errors in the IHDR chunk is more thorough. + +Support for global arrays was removed, to improve thread safety. + +Some obsolete/deprecated macros and functions have been removed. + +Typecasted NULL definitions such as + #define png_voidp_NULL (png_voidp)NULL +were eliminated. If you used these in your application, just use +NULL instead. + +The png_struct and info_struct members "trans" and "trans_values" were +changed to "trans_alpha" and "trans_color", respectively. + +The obsolete, unused pnggccrd.c and pngvcrd.c files and related makefiles +were removed. + +The PNG_1_0_X and PNG_1_2_X macros were eliminated. + +The PNG_LEGACY_SUPPORTED macro was eliminated. + +Many WIN32_WCE #ifdefs were removed. + +The functions png_read_init(info_ptr), png_write_init(info_ptr), +png_info_init(info_ptr), png_read_destroy(), and png_write_destroy() +have been removed. They have been deprecated since libpng-0.95. + +The png_permit_empty_plte() was removed. It has been deprecated +since libpng-1.0.9. Use png_permit_mng_features() instead. + +We removed the obsolete stub functions png_get_mmx_flagmask(), +png_set_mmx_thresholds(), png_get_asm_flags(), +png_get_mmx_bitdepth_threshold(), png_get_mmx_rowbytes_threshold(), +png_set_asm_flags(), and png_mmx_supported() + +We removed the obsolete png_check_sig(), png_memcpy_check(), and +png_memset_check() functions. Instead use !png_sig_cmp(), png_memcpy(), +and png_memset(), respectively. + +The function png_set_gray_1_2_4_to_8() was removed. It has been +deprecated since libpng-1.0.18 and 1.2.9, when it was replaced with +png_set_expand_gray_1_2_4_to_8() because the former function also +expanded palette images. + +We changed the prototype for png_malloc() from + png_malloc(png_structp png_ptr, png_uint_32 size) +to + png_malloc(png_structp png_ptr, png_alloc_size_t size) + +This also applies to the prototype for the user replacement malloc_fn(). + +The png_calloc() function was added and is used in place of +of "png_malloc(); png_memset();" except in the case in png_read_png() +where the array consists of pointers; in this case a "for" loop is used +after the png_malloc() to set the pointers to NULL, to give robust. +behavior in case the application runs out of memory part-way through +the process. + +We changed the prototypes of png_get_compression_buffer_size() and +png_set_compression_buffer_size() to work with png_size_t instead of +png_uint_32. + +Support for numbered error messages was removed by default, since we +never got around to actually numbering the error messages. The function +png_set_strip_error_numbers() was removed from the library by default. + +The png_zalloc() and png_zfree() functions are no longer exported. +The png_zalloc() function no longer zeroes out the memory that it +allocates. + +Support for dithering was disabled by default in libpng-1.4.0, because +been well tested and doesn't actually "dither". The code was not +removed, however, and could be enabled by building libpng with +PNG_READ_DITHER_SUPPORTED defined. In libpng-1.4.2, this support +was reenabled, but the function was renamed png_set_quantize() to +reflect more accurately what it actually does. At the same time, +the PNG_DITHER_[RED,GREEN_BLUE]_BITS macros were also renamed to +PNG_QUANTIZE_[RED,GREEN,BLUE]_BITS. + +We removed the trailing '.' from the warning and error messages. + +X. Detecting libpng + +The png_get_io_ptr() function has been present since libpng-0.88, has never +changed, and is unaffected by conditional compilation macros. It is the +best choice for use in configure scripts for detecting the presence of any +libpng version since 0.88. In an autoconf "configure.in" you could use + + AC_CHECK_LIB(png, png_get_io_ptr, ... + +XI. Source code repository + +Since about February 2009, version 1.2.34, libpng has been under "git" source +control. The git repository was built from old libpng-x.y.z.tar.gz files +going back to version 0.70. You can access the git repository (read only) +at + + git://libpng.git.sourceforge.net/gitroot/libpng + +or you can browse it via "gitweb" at + + http://libpng.git.sourceforge.net/git/gitweb.cgi?p=libpng + +Patches can be sent to glennrp at users.sourceforge.net or to +png-mng-implement at lists.sourceforge.net or you can upload them to +the libpng bug tracker at + + http://libpng.sourceforge.net + +XII. Coding style + +Our coding style is similar to the "Allman" style, with curly +braces on separate lines: + + if (condition) + { + action; + } + + else if (another condition) + { + another action; + } + +The braces can be omitted from simple one-line actions: + + if (condition) + return (0); + +We use 3-space indentation, except for continued statements which +are usually indented the same as the first line of the statement +plus four more spaces. + +For macro definitions we use 2-space indentation, always leaving the "#" +in the first column. + + #ifndef PNG_NO_FEATURE + # ifndef PNG_FEATURE_SUPPORTED + # define PNG_FEATURE_SUPPORTED + # endif + #endif + +Comments appear with the leading "/*" at the same indentation as +the statement that follows the comment: + + /* Single-line comment */ + statement; + + /* This is a multiple-line + * comment. + */ + statement; + +Very short comments can be placed after the end of the statement +to which they pertain: + + statement; /* comment */ + +We don't use C++ style ("//") comments. We have, however, +used them in the past in some now-abandoned MMX assembler +code. + +Functions and their curly braces are not indented, and +exported functions are marked with PNGAPI: + + /* This is a public function that is visible to + * application programers. It does thus-and-so. + */ + void PNGAPI + png_exported_function(png_ptr, png_info, foo) + { + body; + } + +The prototypes for all exported functions appear in png.h, +above the comment that says + + /* Maintainer: Put new public prototypes here ... */ + +We mark all non-exported functions with "/* PRIVATE */"": + + void /* PRIVATE */ + png_non_exported_function(png_ptr, png_info, foo) + { + body; + } + +The prototypes for non-exported functions (except for those in +pngtest) appear in +pngpriv.h +above the comment that says + + /* Maintainer: Put new private prototypes here ^ and in libpngpf.3 */ + +The names of all exported functions and variables begin +with "png_", and all publicly visible C preprocessor +macros begin with "PNG_". + +We put a space after each comma and after each semicolon +in "for" statments, and we put spaces before and after each +C binary operator and after "for" or "while", and before +"?". We don't put a space between a typecast and the expression +being cast, nor do we put one between a function name and the +left parenthesis that follows it: + + for (i = 2; i > 0; --i) + y[i] = a(x) + (int)b; + +We prefer #ifdef and #ifndef to #if defined() and if !defined() +when there is only one macro being tested. + +We do not use the TAB character for indentation in the C sources. + +Lines do not exceed 80 characters. + +Other rules can be inferred by inspecting the libpng source. + +XIII. Y2K Compliance in libpng + +September 23, 2010 + +Since the PNG Development group is an ad-hoc body, we can't make +an official declaration. + +This is your unofficial assurance that libpng from version 0.71 and +upward through 1.4.4 are Y2K compliant. It is my belief that earlier +versions were also Y2K compliant. + +Libpng only has three year fields. One is a 2-byte unsigned integer that +will hold years up to 65535. The other two hold the date in text +format, and will hold years up to 9999. + +The integer is + "png_uint_16 year" in png_time_struct. + +The strings are + "png_charp time_buffer" in png_struct and + "near_time_buffer", which is a local character string in png.c. + +There are seven time-related functions: + + png_convert_to_rfc_1123() in png.c + (formerly png_convert_to_rfc_1152() in error) + png_convert_from_struct_tm() in pngwrite.c, called + in pngwrite.c + png_convert_from_time_t() in pngwrite.c + png_get_tIME() in pngget.c + png_handle_tIME() in pngrutil.c, called in pngread.c + png_set_tIME() in pngset.c + png_write_tIME() in pngwutil.c, called in pngwrite.c + +All appear to handle dates properly in a Y2K environment. The +png_convert_from_time_t() function calls gmtime() to convert from system +clock time, which returns (year - 1900), which we properly convert to +the full 4-digit year. There is a possibility that applications using +libpng are not passing 4-digit years into the png_convert_to_rfc_1123() +function, or that they are incorrectly passing only a 2-digit year +instead of "year - 1900" into the png_convert_from_struct_tm() function, +but this is not under our control. The libpng documentation has always +stated that it works with 4-digit years, and the APIs have been +documented as such. + +The tIME chunk itself is also Y2K compliant. It uses a 2-byte unsigned +integer to hold the year, and can hold years as large as 65535. + +zlib, upon which libpng depends, is also Y2K compliant. It contains +no date-related code. + + + Glenn Randers-Pehrson + libpng maintainer + PNG Development Group diff --git a/libpng/png.c b/libpng/png.c new file mode 100644 index 0000000..f2e5888 --- /dev/null +++ b/libpng/png.c @@ -0,0 +1,918 @@ + +/* png.c - location for general purpose libpng functions + * + * Last changed in libpng 1.4.2 [May 6, 2010] + * Copyright (c) 1998-2010 Glenn Randers-Pehrson + * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) + * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) + * + * This code is released under the libpng license. + * For conditions of distribution and use, see the disclaimer + * and license in png.h + */ + +#define PNG_NO_EXTERN +#define PNG_NO_PEDANTIC_WARNINGS +#include "png.h" +#include "pngpriv.h" + +/* Generate a compiler error if there is an old png.h in the search path. */ +typedef version_1_4_4 Your_png_h_is_not_version_1_4_4; + +/* Version information for C files. This had better match the version + * string defined in png.h. + */ + +/* Tells libpng that we have already handled the first "num_bytes" bytes + * of the PNG file signature. If the PNG data is embedded into another + * stream we can set num_bytes = 8 so that libpng will not attempt to read + * or write any of the magic bytes before it starts on the IHDR. + */ + +#ifdef PNG_READ_SUPPORTED +void PNGAPI +png_set_sig_bytes(png_structp png_ptr, int num_bytes) +{ + png_debug(1, "in png_set_sig_bytes"); + + if (png_ptr == NULL) + return; + + if (num_bytes > 8) + png_error(png_ptr, "Too many bytes for PNG signature"); + + png_ptr->sig_bytes = (png_byte)(num_bytes < 0 ? 0 : num_bytes); +} + +/* Checks whether the supplied bytes match the PNG signature. We allow + * checking less than the full 8-byte signature so that those apps that + * already read the first few bytes of a file to determine the file type + * can simply check the remaining bytes for extra assurance. Returns + * an integer less than, equal to, or greater than zero if sig is found, + * respectively, to be less than, to match, or be greater than the correct + * PNG signature (this is the same behaviour as strcmp, memcmp, etc). + */ +int PNGAPI +png_sig_cmp(png_bytep sig, png_size_t start, png_size_t num_to_check) +{ + png_byte png_signature[8] = {137, 80, 78, 71, 13, 10, 26, 10}; + if (num_to_check > 8) + num_to_check = 8; + else if (num_to_check < 1) + return (-1); + + if (start > 7) + return (-1); + + if (start + num_to_check > 8) + num_to_check = 8 - start; + + return ((int)(png_memcmp(&sig[start], &png_signature[start], num_to_check))); +} + +#endif /* PNG_READ_SUPPORTED */ + +#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED) +/* Function to allocate memory for zlib and clear it to 0. */ +voidpf /* PRIVATE */ +png_zalloc(voidpf png_ptr, uInt items, uInt size) +{ + png_voidp ptr; + png_structp p=(png_structp)png_ptr; + png_uint_32 save_flags=p->flags; + png_alloc_size_t num_bytes; + + if (png_ptr == NULL) + return (NULL); + if (items > PNG_UINT_32_MAX/size) + { + png_warning (p, "Potential overflow in png_zalloc()"); + return (NULL); + } + num_bytes = (png_alloc_size_t)items * size; + + p->flags|=PNG_FLAG_MALLOC_NULL_MEM_OK; + ptr = (png_voidp)png_malloc((png_structp)png_ptr, num_bytes); + p->flags=save_flags; + + return ((voidpf)ptr); +} + +/* Function to free memory for zlib */ +void /* PRIVATE */ +png_zfree(voidpf png_ptr, voidpf ptr) +{ + png_free((png_structp)png_ptr, (png_voidp)ptr); +} + +/* Reset the CRC variable to 32 bits of 1's. Care must be taken + * in case CRC is > 32 bits to leave the top bits 0. + */ +void /* PRIVATE */ +png_reset_crc(png_structp png_ptr) +{ + png_ptr->crc = crc32(0, Z_NULL, 0); +} + +/* Calculate the CRC over a section of data. We can only pass as + * much data to this routine as the largest single buffer size. We + * also check that this data will actually be used before going to the + * trouble of calculating it. + */ +void /* PRIVATE */ +png_calculate_crc(png_structp png_ptr, png_bytep ptr, png_size_t length) +{ + int need_crc = 1; + + if (png_ptr->chunk_name[0] & 0x20) /* ancillary */ + { + if ((png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_MASK) == + (PNG_FLAG_CRC_ANCILLARY_USE | PNG_FLAG_CRC_ANCILLARY_NOWARN)) + need_crc = 0; + } + else /* critical */ + { + if (png_ptr->flags & PNG_FLAG_CRC_CRITICAL_IGNORE) + need_crc = 0; + } + + if (need_crc) + png_ptr->crc = crc32(png_ptr->crc, ptr, (uInt)length); +} + +/* Allocate the memory for an info_struct for the application. We don't + * really need the png_ptr, but it could potentially be useful in the + * future. This should be used in favour of malloc(png_sizeof(png_info)) + * and png_info_init() so that applications that want to use a shared + * libpng don't have to be recompiled if png_info changes size. + */ +png_infop PNGAPI +png_create_info_struct(png_structp png_ptr) +{ + png_infop info_ptr; + + png_debug(1, "in png_create_info_struct"); + + if (png_ptr == NULL) + return (NULL); + +#ifdef PNG_USER_MEM_SUPPORTED + info_ptr = (png_infop)png_create_struct_2(PNG_STRUCT_INFO, + png_ptr->malloc_fn, png_ptr->mem_ptr); +#else + info_ptr = (png_infop)png_create_struct(PNG_STRUCT_INFO); +#endif + if (info_ptr != NULL) + png_info_init_3(&info_ptr, png_sizeof(png_info)); + + return (info_ptr); +} + +/* This function frees the memory associated with a single info struct. + * Normally, one would use either png_destroy_read_struct() or + * png_destroy_write_struct() to free an info struct, but this may be + * useful for some applications. + */ +void PNGAPI +png_destroy_info_struct(png_structp png_ptr, png_infopp info_ptr_ptr) +{ + png_infop info_ptr = NULL; + + png_debug(1, "in png_destroy_info_struct"); + + if (png_ptr == NULL) + return; + + if (info_ptr_ptr != NULL) + info_ptr = *info_ptr_ptr; + + if (info_ptr != NULL) + { + png_info_destroy(png_ptr, info_ptr); + +#ifdef PNG_USER_MEM_SUPPORTED + png_destroy_struct_2((png_voidp)info_ptr, png_ptr->free_fn, + png_ptr->mem_ptr); +#else + png_destroy_struct((png_voidp)info_ptr); +#endif + *info_ptr_ptr = NULL; + } +} + +/* Initialize the info structure. This is now an internal function (0.89) + * and applications using it are urged to use png_create_info_struct() + * instead. + */ + +void PNGAPI +png_info_init_3(png_infopp ptr_ptr, png_size_t png_info_struct_size) +{ + png_infop info_ptr = *ptr_ptr; + + png_debug(1, "in png_info_init_3"); + + if (info_ptr == NULL) + return; + + if (png_sizeof(png_info) > png_info_struct_size) + { + png_destroy_struct(info_ptr); + info_ptr = (png_infop)png_create_struct(PNG_STRUCT_INFO); + *ptr_ptr = info_ptr; + } + + /* Set everything to 0 */ + png_memset(info_ptr, 0, png_sizeof(png_info)); +} + +void PNGAPI +png_data_freer(png_structp png_ptr, png_infop info_ptr, + int freer, png_uint_32 mask) +{ + png_debug(1, "in png_data_freer"); + + if (png_ptr == NULL || info_ptr == NULL) + return; + + if (freer == PNG_DESTROY_WILL_FREE_DATA) + info_ptr->free_me |= mask; + else if (freer == PNG_USER_WILL_FREE_DATA) + info_ptr->free_me &= ~mask; + else + png_warning(png_ptr, + "Unknown freer parameter in png_data_freer"); +} + +void PNGAPI +png_free_data(png_structp png_ptr, png_infop info_ptr, png_uint_32 mask, + int num) +{ + png_debug(1, "in png_free_data"); + + if (png_ptr == NULL || info_ptr == NULL) + return; + +#ifdef PNG_TEXT_SUPPORTED + /* Free text item num or (if num == -1) all text items */ + if ((mask & PNG_FREE_TEXT) & info_ptr->free_me) + { + if (num != -1) + { + if (info_ptr->text && info_ptr->text[num].key) + { + png_free(png_ptr, info_ptr->text[num].key); + info_ptr->text[num].key = NULL; + } + } + else + { + int i; + for (i = 0; i < info_ptr->num_text; i++) + png_free_data(png_ptr, info_ptr, PNG_FREE_TEXT, i); + png_free(png_ptr, info_ptr->text); + info_ptr->text = NULL; + info_ptr->num_text=0; + } + } +#endif + +#ifdef PNG_tRNS_SUPPORTED + /* Free any tRNS entry */ + if ((mask & PNG_FREE_TRNS) & info_ptr->free_me) + { + png_free(png_ptr, info_ptr->trans_alpha); + info_ptr->trans_alpha = NULL; + info_ptr->valid &= ~PNG_INFO_tRNS; + } +#endif + +#ifdef PNG_sCAL_SUPPORTED + /* Free any sCAL entry */ + if ((mask & PNG_FREE_SCAL) & info_ptr->free_me) + { +#if defined(PNG_FIXED_POINT_SUPPORTED) && !defined(PNG_FLOATING_POINT_SUPPORTED) + png_free(png_ptr, info_ptr->scal_s_width); + png_free(png_ptr, info_ptr->scal_s_height); + info_ptr->scal_s_width = NULL; + info_ptr->scal_s_height = NULL; +#endif + info_ptr->valid &= ~PNG_INFO_sCAL; + } +#endif + +#ifdef PNG_pCAL_SUPPORTED + /* Free any pCAL entry */ + if ((mask & PNG_FREE_PCAL) & info_ptr->free_me) + { + png_free(png_ptr, info_ptr->pcal_purpose); + png_free(png_ptr, info_ptr->pcal_units); + info_ptr->pcal_purpose = NULL; + info_ptr->pcal_units = NULL; + if (info_ptr->pcal_params != NULL) + { + int i; + for (i = 0; i < (int)info_ptr->pcal_nparams; i++) + { + png_free(png_ptr, info_ptr->pcal_params[i]); + info_ptr->pcal_params[i] = NULL; + } + png_free(png_ptr, info_ptr->pcal_params); + info_ptr->pcal_params = NULL; + } + info_ptr->valid &= ~PNG_INFO_pCAL; + } +#endif + +#ifdef PNG_iCCP_SUPPORTED + /* Free any iCCP entry */ + if ((mask & PNG_FREE_ICCP) & info_ptr->free_me) + { + png_free(png_ptr, info_ptr->iccp_name); + png_free(png_ptr, info_ptr->iccp_profile); + info_ptr->iccp_name = NULL; + info_ptr->iccp_profile = NULL; + info_ptr->valid &= ~PNG_INFO_iCCP; + } +#endif + +#ifdef PNG_sPLT_SUPPORTED + /* Free a given sPLT entry, or (if num == -1) all sPLT entries */ + if ((mask & PNG_FREE_SPLT) & info_ptr->free_me) + { + if (num != -1) + { + if (info_ptr->splt_palettes) + { + png_free(png_ptr, info_ptr->splt_palettes[num].name); + png_free(png_ptr, info_ptr->splt_palettes[num].entries); + info_ptr->splt_palettes[num].name = NULL; + info_ptr->splt_palettes[num].entries = NULL; + } + } + else + { + if (info_ptr->splt_palettes_num) + { + int i; + for (i = 0; i < (int)info_ptr->splt_palettes_num; i++) + png_free_data(png_ptr, info_ptr, PNG_FREE_SPLT, i); + + png_free(png_ptr, info_ptr->splt_palettes); + info_ptr->splt_palettes = NULL; + info_ptr->splt_palettes_num = 0; + } + info_ptr->valid &= ~PNG_INFO_sPLT; + } + } +#endif + +#ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED + if (png_ptr->unknown_chunk.data) + { + png_free(png_ptr, png_ptr->unknown_chunk.data); + png_ptr->unknown_chunk.data = NULL; + } + + if ((mask & PNG_FREE_UNKN) & info_ptr->free_me) + { + if (num != -1) + { + if (info_ptr->unknown_chunks) + { + png_free(png_ptr, info_ptr->unknown_chunks[num].data); + info_ptr->unknown_chunks[num].data = NULL; + } + } + else + { + int i; + + if (info_ptr->unknown_chunks_num) + { + for (i = 0; i < (int)info_ptr->unknown_chunks_num; i++) + png_free_data(png_ptr, info_ptr, PNG_FREE_UNKN, i); + + png_free(png_ptr, info_ptr->unknown_chunks); + info_ptr->unknown_chunks = NULL; + info_ptr->unknown_chunks_num = 0; + } + } + } +#endif + +#ifdef PNG_hIST_SUPPORTED + /* Free any hIST entry */ + if ((mask & PNG_FREE_HIST) & info_ptr->free_me) + { + png_free(png_ptr, info_ptr->hist); + info_ptr->hist = NULL; + info_ptr->valid &= ~PNG_INFO_hIST; + } +#endif + + /* Free any PLTE entry that was internally allocated */ + if ((mask & PNG_FREE_PLTE) & info_ptr->free_me) + { + png_zfree(png_ptr, info_ptr->palette); + info_ptr->palette = NULL; + info_ptr->valid &= ~PNG_INFO_PLTE; + info_ptr->num_palette = 0; + } + +#ifdef PNG_INFO_IMAGE_SUPPORTED + /* Free any image bits attached to the info structure */ + if ((mask & PNG_FREE_ROWS) & info_ptr->free_me) + { + if (info_ptr->row_pointers) + { + int row; + for (row = 0; row < (int)info_ptr->height; row++) + { + png_free(png_ptr, info_ptr->row_pointers[row]); + info_ptr->row_pointers[row] = NULL; + } + png_free(png_ptr, info_ptr->row_pointers); + info_ptr->row_pointers = NULL; + } + info_ptr->valid &= ~PNG_INFO_IDAT; + } +#endif + + if (num == -1) + info_ptr->free_me &= ~mask; + else + info_ptr->free_me &= ~(mask & ~PNG_FREE_MUL); +} + +/* This is an internal routine to free any memory that the info struct is + * pointing to before re-using it or freeing the struct itself. Recall + * that png_free() checks for NULL pointers for us. + */ +void /* PRIVATE */ +png_info_destroy(png_structp png_ptr, png_infop info_ptr) +{ + png_debug(1, "in png_info_destroy"); + + png_free_data(png_ptr, info_ptr, PNG_FREE_ALL, -1); + +#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED + if (png_ptr->num_chunk_list) + { + png_free(png_ptr, png_ptr->chunk_list); + png_ptr->chunk_list = NULL; + png_ptr->num_chunk_list = 0; + } +#endif + + png_info_init_3(&info_ptr, png_sizeof(png_info)); +} +#endif /* defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED) */ + +/* This function returns a pointer to the io_ptr associated with the user + * functions. The application should free any memory associated with this + * pointer before png_write_destroy() or png_read_destroy() are called. + */ +png_voidp PNGAPI +png_get_io_ptr(png_structp png_ptr) +{ + if (png_ptr == NULL) + return (NULL); + return (png_ptr->io_ptr); +} + +#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED) +#ifdef PNG_STDIO_SUPPORTED +/* Initialize the default input/output functions for the PNG file. If you + * use your own read or write routines, you can call either png_set_read_fn() + * or png_set_write_fn() instead of png_init_io(). If you have defined + * PNG_NO_STDIO, you must use a function of your own because "FILE *" isn't + * necessarily available. + */ +void PNGAPI +png_init_io(png_structp png_ptr, png_FILE_p fp) +{ + png_debug(1, "in png_init_io"); + + if (png_ptr == NULL) + return; + + png_ptr->io_ptr = (png_voidp)fp; +} +#endif + +#ifdef PNG_TIME_RFC1123_SUPPORTED +/* Convert the supplied time into an RFC 1123 string suitable for use in + * a "Creation Time" or other text-based time string. + */ +png_charp PNGAPI +png_convert_to_rfc1123(png_structp png_ptr, png_timep ptime) +{ + static PNG_CONST char short_months[12][4] = + {"Jan", "Feb", "Mar", "Apr", "May", "Jun", + "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"}; + + if (png_ptr == NULL) + return (NULL); + if (png_ptr->time_buffer == NULL) + { + png_ptr->time_buffer = (png_charp)png_malloc(png_ptr, (png_uint_32)(29* + png_sizeof(char))); + } + +#ifdef USE_FAR_KEYWORD + { + char near_time_buf[29]; + png_snprintf6(near_time_buf, 29, "%d %s %d %02d:%02d:%02d +0000", + ptime->day % 32, short_months[(ptime->month - 1) % 12], + ptime->year, ptime->hour % 24, ptime->minute % 60, + ptime->second % 61); + png_memcpy(png_ptr->time_buffer, near_time_buf, + 29*png_sizeof(char)); + } +#else + png_snprintf6(png_ptr->time_buffer, 29, "%d %s %d %02d:%02d:%02d +0000", + ptime->day % 32, short_months[(ptime->month - 1) % 12], + ptime->year, ptime->hour % 24, ptime->minute % 60, + ptime->second % 61); +#endif + return ((png_charp)png_ptr->time_buffer); +} +#endif /* PNG_TIME_RFC1123_SUPPORTED */ + +#endif /* defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED) */ + +png_charp PNGAPI +png_get_copyright(png_structp png_ptr) +{ + png_ptr = png_ptr; /* Silence compiler warning about unused png_ptr */ +#ifdef PNG_STRING_COPYRIGHT + return PNG_STRING_COPYRIGHT +#else +#ifdef __STDC__ + return ((png_charp) PNG_STRING_NEWLINE \ + "libpng version 1.4.4 - September 23, 2010" PNG_STRING_NEWLINE \ + "Copyright (c) 1998-2010 Glenn Randers-Pehrson" PNG_STRING_NEWLINE \ + "Copyright (c) 1996-1997 Andreas Dilger" PNG_STRING_NEWLINE \ + "Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc." \ + PNG_STRING_NEWLINE); +#else + return ((png_charp) "libpng version 1.4.4 - September 23, 2010\ + Copyright (c) 1998-2010 Glenn Randers-Pehrson\ + Copyright (c) 1996-1997 Andreas Dilger\ + Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc."); +#endif +#endif +} + +/* The following return the library version as a short string in the + * format 1.0.0 through 99.99.99zz. To get the version of *.h files + * used with your application, print out PNG_LIBPNG_VER_STRING, which + * is defined in png.h. + * Note: now there is no difference between png_get_libpng_ver() and + * png_get_header_ver(). Due to the version_nn_nn_nn typedef guard, + * it is guaranteed that png.c uses the correct version of png.h. + */ +png_charp PNGAPI +png_get_libpng_ver(png_structp png_ptr) +{ + /* Version of *.c files used when building libpng */ + png_ptr = png_ptr; /* Silence compiler warning about unused png_ptr */ + return ((png_charp) PNG_LIBPNG_VER_STRING); +} + +png_charp PNGAPI +png_get_header_ver(png_structp png_ptr) +{ + /* Version of *.h files used when building libpng */ + png_ptr = png_ptr; /* Silence compiler warning about unused png_ptr */ + return ((png_charp) PNG_LIBPNG_VER_STRING); +} + +png_charp PNGAPI +png_get_header_version(png_structp png_ptr) +{ + /* Returns longer string containing both version and date */ + png_ptr = png_ptr; /* Silence compiler warning about unused png_ptr */ +#ifdef __STDC__ + return ((png_charp) PNG_HEADER_VERSION_STRING +#ifndef PNG_READ_SUPPORTED + " (NO READ SUPPORT)" +#endif + PNG_STRING_NEWLINE); +#else + return ((png_charp) PNG_HEADER_VERSION_STRING); +#endif +} + +#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED) +#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED +int PNGAPI +png_handle_as_unknown(png_structp png_ptr, png_bytep chunk_name) +{ + /* Check chunk_name and return "keep" value if it's on the list, else 0 */ + int i; + png_bytep p; + if (png_ptr == NULL || chunk_name == NULL || png_ptr->num_chunk_list<=0) + return 0; + p = png_ptr->chunk_list + png_ptr->num_chunk_list*5 - 5; + for (i = png_ptr->num_chunk_list; i; i--, p -= 5) + if (!png_memcmp(chunk_name, p, 4)) + return ((int)*(p + 4)); + return 0; +} +#endif +#endif /* defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED) */ + +#ifdef PNG_READ_SUPPORTED +/* This function, added to libpng-1.0.6g, is untested. */ +int PNGAPI +png_reset_zstream(png_structp png_ptr) +{ + if (png_ptr == NULL) + return Z_STREAM_ERROR; + return (inflateReset(&png_ptr->zstream)); +} +#endif /* PNG_READ_SUPPORTED */ + +/* This function was added to libpng-1.0.7 */ +png_uint_32 PNGAPI +png_access_version_number(void) +{ + /* Version of *.c files used when building libpng */ + return((png_uint_32) PNG_LIBPNG_VER); +} + + + +#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED) +#ifdef PNG_SIZE_T +/* Added at libpng version 1.2.6 */ + PNG_EXTERN png_size_t PNGAPI png_convert_size PNGARG((size_t size)); +png_size_t PNGAPI +png_convert_size(size_t size) +{ + if (size > (png_size_t)-1) + PNG_ABORT(); /* We haven't got access to png_ptr, so no png_error() */ + return ((png_size_t)size); +} +#endif /* PNG_SIZE_T */ + +/* Added at libpng version 1.2.34 and 1.4.0 (moved from pngset.c) */ +#ifdef PNG_cHRM_SUPPORTED +#ifdef PNG_CHECK_cHRM_SUPPORTED + +/* + * Multiply two 32-bit numbers, V1 and V2, using 32-bit + * arithmetic, to produce a 64 bit result in the HI/LO words. + * + * A B + * x C D + * ------ + * AD || BD + * AC || CB || 0 + * + * where A and B are the high and low 16-bit words of V1, + * C and D are the 16-bit words of V2, AD is the product of + * A and D, and X || Y is (X << 16) + Y. +*/ + +void /* PRIVATE */ +png_64bit_product (long v1, long v2, unsigned long *hi_product, + unsigned long *lo_product) +{ + int a, b, c, d; + long lo, hi, x, y; + + a = (v1 >> 16) & 0xffff; + b = v1 & 0xffff; + c = (v2 >> 16) & 0xffff; + d = v2 & 0xffff; + + lo = b * d; /* BD */ + x = a * d + c * b; /* AD + CB */ + y = ((lo >> 16) & 0xffff) + x; + + lo = (lo & 0xffff) | ((y & 0xffff) << 16); + hi = (y >> 16) & 0xffff; + + hi += a * c; /* AC */ + + *hi_product = (unsigned long)hi; + *lo_product = (unsigned long)lo; +} + +int /* PRIVATE */ +png_check_cHRM_fixed(png_structp png_ptr, + png_fixed_point white_x, png_fixed_point white_y, png_fixed_point red_x, + png_fixed_point red_y, png_fixed_point green_x, png_fixed_point green_y, + png_fixed_point blue_x, png_fixed_point blue_y) +{ + int ret = 1; + unsigned long xy_hi,xy_lo,yx_hi,yx_lo; + + png_debug(1, "in function png_check_cHRM_fixed"); + + if (png_ptr == NULL) + return 0; + + if (white_x < 0 || white_y <= 0 || + red_x < 0 || red_y < 0 || + green_x < 0 || green_y < 0 || + blue_x < 0 || blue_y < 0) + { + png_warning(png_ptr, + "Ignoring attempt to set negative chromaticity value"); + ret = 0; + } + if (white_x > (png_fixed_point) PNG_UINT_31_MAX || + white_y > (png_fixed_point) PNG_UINT_31_MAX || + red_x > (png_fixed_point) PNG_UINT_31_MAX || + red_y > (png_fixed_point) PNG_UINT_31_MAX || + green_x > (png_fixed_point) PNG_UINT_31_MAX || + green_y > (png_fixed_point) PNG_UINT_31_MAX || + blue_x > (png_fixed_point) PNG_UINT_31_MAX || + blue_y > (png_fixed_point) PNG_UINT_31_MAX ) + { + png_warning(png_ptr, + "Ignoring attempt to set chromaticity value exceeding 21474.83"); + ret = 0; + } + if (white_x > 100000L - white_y) + { + png_warning(png_ptr, "Invalid cHRM white point"); + ret = 0; + } + if (red_x > 100000L - red_y) + { + png_warning(png_ptr, "Invalid cHRM red point"); + ret = 0; + } + if (green_x > 100000L - green_y) + { + png_warning(png_ptr, "Invalid cHRM green point"); + ret = 0; + } + if (blue_x > 100000L - blue_y) + { + png_warning(png_ptr, "Invalid cHRM blue point"); + ret = 0; + } + + png_64bit_product(green_x - red_x, blue_y - red_y, &xy_hi, &xy_lo); + png_64bit_product(green_y - red_y, blue_x - red_x, &yx_hi, &yx_lo); + + if (xy_hi == yx_hi && xy_lo == yx_lo) + { + png_warning(png_ptr, + "Ignoring attempt to set cHRM RGB triangle with zero area"); + ret = 0; + } + + return ret; +} +#endif /* PNG_CHECK_cHRM_SUPPORTED */ +#endif /* PNG_cHRM_SUPPORTED */ + +void /* PRIVATE */ +png_check_IHDR(png_structp png_ptr, + png_uint_32 width, png_uint_32 height, int bit_depth, + int color_type, int interlace_type, int compression_type, + int filter_type) +{ + int error = 0; + + /* Check for width and height valid values */ + if (width == 0) + { + png_warning(png_ptr, "Image width is zero in IHDR"); + error = 1; + } + + if (height == 0) + { + png_warning(png_ptr, "Image height is zero in IHDR"); + error = 1; + } + +#ifdef PNG_SET_USER_LIMITS_SUPPORTED + if (width > png_ptr->user_width_max || width > PNG_USER_WIDTH_MAX) +#else + if (width > PNG_USER_WIDTH_MAX) +#endif + { + png_warning(png_ptr, "Image width exceeds user limit in IHDR"); + error = 1; + } + +#ifdef PNG_SET_USER_LIMITS_SUPPORTED + if (height > png_ptr->user_height_max || height > PNG_USER_HEIGHT_MAX) +#else + if (height > PNG_USER_HEIGHT_MAX) +#endif + { + png_warning(png_ptr, "Image height exceeds user limit in IHDR"); + error = 1; + } + + if (width > PNG_UINT_31_MAX) + { + png_warning(png_ptr, "Invalid image width in IHDR"); + error = 1; + } + + if ( height > PNG_UINT_31_MAX) + { + png_warning(png_ptr, "Invalid image height in IHDR"); + error = 1; + } + + if ( width > (PNG_UINT_32_MAX + >> 3) /* 8-byte RGBA pixels */ + - 64 /* bigrowbuf hack */ + - 1 /* filter byte */ + - 7*8 /* rounding of width to multiple of 8 pixels */ + - 8) /* extra max_pixel_depth pad */ + png_warning(png_ptr, "Width is too large for libpng to process pixels"); + + /* Check other values */ + if (bit_depth != 1 && bit_depth != 2 && bit_depth != 4 && + bit_depth != 8 && bit_depth != 16) + { + png_warning(png_ptr, "Invalid bit depth in IHDR"); + error = 1; + } + + if (color_type < 0 || color_type == 1 || + color_type == 5 || color_type > 6) + { + png_warning(png_ptr, "Invalid color type in IHDR"); + error = 1; + } + + if (((color_type == PNG_COLOR_TYPE_PALETTE) && bit_depth > 8) || + ((color_type == PNG_COLOR_TYPE_RGB || + color_type == PNG_COLOR_TYPE_GRAY_ALPHA || + color_type == PNG_COLOR_TYPE_RGB_ALPHA) && bit_depth < 8)) + { + png_warning(png_ptr, "Invalid color type/bit depth combination in IHDR"); + error = 1; + } + + if (interlace_type >= PNG_INTERLACE_LAST) + { + png_warning(png_ptr, "Unknown interlace method in IHDR"); + error = 1; + } + + if (compression_type != PNG_COMPRESSION_TYPE_BASE) + { + png_warning(png_ptr, "Unknown compression method in IHDR"); + error = 1; + } + +#ifdef PNG_MNG_FEATURES_SUPPORTED + /* Accept filter_method 64 (intrapixel differencing) only if + * 1. Libpng was compiled with PNG_MNG_FEATURES_SUPPORTED and + * 2. Libpng did not read a PNG signature (this filter_method is only + * used in PNG datastreams that are embedded in MNG datastreams) and + * 3. The application called png_permit_mng_features with a mask that + * included PNG_FLAG_MNG_FILTER_64 and + * 4. The filter_method is 64 and + * 5. The color_type is RGB or RGBA + */ + if ((png_ptr->mode & PNG_HAVE_PNG_SIGNATURE) && + png_ptr->mng_features_permitted) + png_warning(png_ptr, "MNG features are not allowed in a PNG datastream"); + + if (filter_type != PNG_FILTER_TYPE_BASE) + { + if (!((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) && + (filter_type == PNG_INTRAPIXEL_DIFFERENCING) && + ((png_ptr->mode & PNG_HAVE_PNG_SIGNATURE) == 0) && + (color_type == PNG_COLOR_TYPE_RGB || + color_type == PNG_COLOR_TYPE_RGB_ALPHA))) + { + png_warning(png_ptr, "Unknown filter method in IHDR"); + error = 1; + } + + if (png_ptr->mode & PNG_HAVE_PNG_SIGNATURE) + { + png_warning(png_ptr, "Invalid filter method in IHDR"); + error = 1; + } + } + +#else + if (filter_type != PNG_FILTER_TYPE_BASE) + { + png_warning(png_ptr, "Unknown filter method in IHDR"); + error = 1; + } +#endif + + if (error == 1) + png_error(png_ptr, "Invalid IHDR data"); +} +#endif /* defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED) */ diff --git a/libpng/png.h b/libpng/png.h new file mode 100644 index 0000000..805be12 --- /dev/null +++ b/libpng/png.h @@ -0,0 +1,2699 @@ + +/* png.h - header file for PNG reference library + * + * libpng version 1.4.4 - September 23, 2010 + * Copyright (c) 1998-2010 Glenn Randers-Pehrson + * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) + * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) + * + * This code is released under the libpng license (See LICENSE, below) + * + * Authors and maintainers: + * libpng versions 0.71, May 1995, through 0.88, January 1996: Guy Schalnat + * libpng versions 0.89c, June 1996, through 0.96, May 1997: Andreas Dilger + * libpng versions 0.97, January 1998, through 1.4.4 - September 23, 2010: Glenn + * See also "Contributing Authors", below. + * + * Note about libpng version numbers: + * + * Due to various miscommunications, unforeseen code incompatibilities + * and occasional factors outside the authors' control, version numbering + * on the library has not always been consistent and straightforward. + * The following table summarizes matters since version 0.89c, which was + * the first widely used release: + * + * source png.h png.h shared-lib + * version string int version + * ------- ------ ----- ---------- + * 0.89c "1.0 beta 3" 0.89 89 1.0.89 + * 0.90 "1.0 beta 4" 0.90 90 0.90 [should have been 2.0.90] + * 0.95 "1.0 beta 5" 0.95 95 0.95 [should have been 2.0.95] + * 0.96 "1.0 beta 6" 0.96 96 0.96 [should have been 2.0.96] + * 0.97b "1.00.97 beta 7" 1.00.97 97 1.0.1 [should have been 2.0.97] + * 0.97c 0.97 97 2.0.97 + * 0.98 0.98 98 2.0.98 + * 0.99 0.99 98 2.0.99 + * 0.99a-m 0.99 99 2.0.99 + * 1.00 1.00 100 2.1.0 [100 should be 10000] + * 1.0.0 (from here on, the 100 2.1.0 [100 should be 10000] + * 1.0.1 png.h string is 10001 2.1.0 + * 1.0.1a-e identical to the 10002 from here on, the shared library + * 1.0.2 source version) 10002 is 2.V where V is the source code + * 1.0.2a-b 10003 version, except as noted. + * 1.0.3 10003 + * 1.0.3a-d 10004 + * 1.0.4 10004 + * 1.0.4a-f 10005 + * 1.0.5 (+ 2 patches) 10005 + * 1.0.5a-d 10006 + * 1.0.5e-r 10100 (not source compatible) + * 1.0.5s-v 10006 (not binary compatible) + * 1.0.6 (+ 3 patches) 10006 (still binary incompatible) + * 1.0.6d-f 10007 (still binary incompatible) + * 1.0.6g 10007 + * 1.0.6h 10007 10.6h (testing xy.z so-numbering) + * 1.0.6i 10007 10.6i + * 1.0.6j 10007 2.1.0.6j (incompatible with 1.0.0) + * 1.0.7beta11-14 DLLNUM 10007 2.1.0.7beta11-14 (binary compatible) + * 1.0.7beta15-18 1 10007 2.1.0.7beta15-18 (binary compatible) + * 1.0.7rc1-2 1 10007 2.1.0.7rc1-2 (binary compatible) + * 1.0.7 1 10007 (still compatible) + * 1.0.8beta1-4 1 10008 2.1.0.8beta1-4 + * 1.0.8rc1 1 10008 2.1.0.8rc1 + * 1.0.8 1 10008 2.1.0.8 + * 1.0.9beta1-6 1 10009 2.1.0.9beta1-6 + * 1.0.9rc1 1 10009 2.1.0.9rc1 + * 1.0.9beta7-10 1 10009 2.1.0.9beta7-10 + * 1.0.9rc2 1 10009 2.1.0.9rc2 + * 1.0.9 1 10009 2.1.0.9 + * 1.0.10beta1 1 10010 2.1.0.10beta1 + * 1.0.10rc1 1 10010 2.1.0.10rc1 + * 1.0.10 1 10010 2.1.0.10 + * 1.0.11beta1-3 1 10011 2.1.0.11beta1-3 + * 1.0.11rc1 1 10011 2.1.0.11rc1 + * 1.0.11 1 10011 2.1.0.11 + * 1.0.12beta1-2 2 10012 2.1.0.12beta1-2 + * 1.0.12rc1 2 10012 2.1.0.12rc1 + * 1.0.12 2 10012 2.1.0.12 + * 1.1.0a-f - 10100 2.1.1.0a-f (branch abandoned) + * 1.2.0beta1-2 2 10200 2.1.2.0beta1-2 + * 1.2.0beta3-5 3 10200 3.1.2.0beta3-5 + * 1.2.0rc1 3 10200 3.1.2.0rc1 + * 1.2.0 3 10200 3.1.2.0 + * 1.2.1beta1-4 3 10201 3.1.2.1beta1-4 + * 1.2.1rc1-2 3 10201 3.1.2.1rc1-2 + * 1.2.1 3 10201 3.1.2.1 + * 1.2.2beta1-6 12 10202 12.so.0.1.2.2beta1-6 + * 1.0.13beta1 10 10013 10.so.0.1.0.13beta1 + * 1.0.13rc1 10 10013 10.so.0.1.0.13rc1 + * 1.2.2rc1 12 10202 12.so.0.1.2.2rc1 + * 1.0.13 10 10013 10.so.0.1.0.13 + * 1.2.2 12 10202 12.so.0.1.2.2 + * 1.2.3rc1-6 12 10203 12.so.0.1.2.3rc1-6 + * 1.2.3 12 10203 12.so.0.1.2.3 + * 1.2.4beta1-3 13 10204 12.so.0.1.2.4beta1-3 + * 1.0.14rc1 13 10014 10.so.0.1.0.14rc1 + * 1.2.4rc1 13 10204 12.so.0.1.2.4rc1 + * 1.0.14 10 10014 10.so.0.1.0.14 + * 1.2.4 13 10204 12.so.0.1.2.4 + * 1.2.5beta1-2 13 10205 12.so.0.1.2.5beta1-2 + * 1.0.15rc1-3 10 10015 10.so.0.1.0.15rc1-3 + * 1.2.5rc1-3 13 10205 12.so.0.1.2.5rc1-3 + * 1.0.15 10 10015 10.so.0.1.0.15 + * 1.2.5 13 10205 12.so.0.1.2.5 + * 1.2.6beta1-4 13 10206 12.so.0.1.2.6beta1-4 + * 1.0.16 10 10016 10.so.0.1.0.16 + * 1.2.6 13 10206 12.so.0.1.2.6 + * 1.2.7beta1-2 13 10207 12.so.0.1.2.7beta1-2 + * 1.0.17rc1 10 10017 12.so.0.1.0.17rc1 + * 1.2.7rc1 13 10207 12.so.0.1.2.7rc1 + * 1.0.17 10 10017 12.so.0.1.0.17 + * 1.2.7 13 10207 12.so.0.1.2.7 + * 1.2.8beta1-5 13 10208 12.so.0.1.2.8beta1-5 + * 1.0.18rc1-5 10 10018 12.so.0.1.0.18rc1-5 + * 1.2.8rc1-5 13 10208 12.so.0.1.2.8rc1-5 + * 1.0.18 10 10018 12.so.0.1.0.18 + * 1.2.8 13 10208 12.so.0.1.2.8 + * 1.2.9beta1-3 13 10209 12.so.0.1.2.9beta1-3 + * 1.2.9beta4-11 13 10209 12.so.0.9[.0] + * 1.2.9rc1 13 10209 12.so.0.9[.0] + * 1.2.9 13 10209 12.so.0.9[.0] + * 1.2.10beta1-7 13 10210 12.so.0.10[.0] + * 1.2.10rc1-2 13 10210 12.so.0.10[.0] + * 1.2.10 13 10210 12.so.0.10[.0] + * 1.4.0beta1-5 14 10400 14.so.0.0[.0] + * 1.2.11beta1-4 13 10211 12.so.0.11[.0] + * 1.4.0beta7-8 14 10400 14.so.0.0[.0] + * 1.2.11 13 10211 12.so.0.11[.0] + * 1.2.12 13 10212 12.so.0.12[.0] + * 1.4.0beta9-14 14 10400 14.so.0.0[.0] + * 1.2.13 13 10213 12.so.0.13[.0] + * 1.4.0beta15-36 14 10400 14.so.0.0[.0] + * 1.4.0beta37-87 14 10400 14.so.14.0[.0] + * 1.4.0rc01 14 10400 14.so.14.0[.0] + * 1.4.0beta88-109 14 10400 14.so.14.0[.0] + * 1.4.0rc02-08 14 10400 14.so.14.0[.0] + * 1.4.0 14 10400 14.so.14.0[.0] + * 1.4.1beta01-03 14 10401 14.so.14.1[.0] + * 1.4.1rc01 14 10401 14.so.14.1[.0] + * 1.4.1beta04-12 14 10401 14.so.14.1[.0] + * 1.4.1rc02-04 14 10401 14.so.14.1[.0] + * 1.4.1 14 10401 14.so.14.1[.0] + * 1.4.2beta01 14 10402 14.so.14.2[.0] + * 1.4.2rc02-06 14 10402 14.so.14.2[.0] + * 1.4.2 14 10402 14.so.14.2[.0] + * 1.4.3beta01-05 14 10403 14.so.14.3[.0] + * 1.4.3rc01-03 14 10403 14.so.14.3[.0] + * 1.4.3 14 10403 14.so.14.3[.0] + * 1.4.4beta01-08 14 10404 14.so.14.4[.0] + * 1.4.4rc01-06 14 10404 14.so.14.4[.0] + * + * Henceforth the source version will match the shared-library major + * and minor numbers; the shared-library major version number will be + * used for changes in backward compatibility, as it is intended. The + * PNG_LIBPNG_VER macro, which is not used within libpng but is available + * for applications, is an unsigned integer of the form xyyzz corresponding + * to the source version x.y.z (leading zeros in y and z). Beta versions + * were given the previous public release number plus a letter, until + * version 1.0.6j; from then on they were given the upcoming public + * release number plus "betaNN" or "rcN". + * + * Binary incompatibility exists only when applications make direct access + * to the info_ptr or png_ptr members through png.h, and the compiled + * application is loaded with a different version of the library. + * + * DLLNUM will change each time there are forward or backward changes + * in binary compatibility (e.g., when a new feature is added). + * + * See libpng.txt or libpng.3 for more information. The PNG specification + * is available as a W3C Recommendation and as an ISO Specification, + * defines should NOT be changed. + */ +#define PNG_INFO_gAMA 0x0001 +#define PNG_INFO_sBIT 0x0002 +#define PNG_INFO_cHRM 0x0004 +#define PNG_INFO_PLTE 0x0008 +#define PNG_INFO_tRNS 0x0010 +#define PNG_INFO_bKGD 0x0020 +#define PNG_INFO_hIST 0x0040 +#define PNG_INFO_pHYs 0x0080 +#define PNG_INFO_oFFs 0x0100 +#define PNG_INFO_tIME 0x0200 +#define PNG_INFO_pCAL 0x0400 +#define PNG_INFO_sRGB 0x0800 /* GR-P, 0.96a */ +#define PNG_INFO_iCCP 0x1000 /* ESR, 1.0.6 */ +#define PNG_INFO_sPLT 0x2000 /* ESR, 1.0.6 */ +#define PNG_INFO_sCAL 0x4000 /* ESR, 1.0.6 */ +#define PNG_INFO_IDAT 0x8000L /* ESR, 1.0.6 */ + +/* This is used for the transformation routines, as some of them + * change these values for the row. It also should enable using + * the routines for other purposes. + */ +typedef struct png_row_info_struct +{ + png_uint_32 width; /* width of row */ + png_size_t rowbytes; /* number of bytes in row */ + png_byte color_type; /* color type of row */ + png_byte bit_depth; /* bit depth of row */ + png_byte channels; /* number of channels (1, 2, 3, or 4) */ + png_byte pixel_depth; /* bits per pixel (depth * channels) */ +} png_row_info; + +typedef png_row_info FAR * png_row_infop; +typedef png_row_info FAR * FAR * png_row_infopp; + +/* These are the function types for the I/O functions and for the functions + * that allow the user to override the default I/O functions with his or her + * own. The png_error_ptr type should match that of user-supplied warning + * and error functions, while the png_rw_ptr type should match that of the + * user read/write data functions. + */ +typedef struct png_struct_def png_struct; +typedef png_struct FAR * png_structp; + +typedef void (PNGAPI *png_error_ptr) PNGARG((png_structp, png_const_charp)); +typedef void (PNGAPI *png_rw_ptr) PNGARG((png_structp, png_bytep, png_size_t)); +typedef void (PNGAPI *png_flush_ptr) PNGARG((png_structp)); +typedef void (PNGAPI *png_read_status_ptr) PNGARG((png_structp, png_uint_32, + int)); +typedef void (PNGAPI *png_write_status_ptr) PNGARG((png_structp, png_uint_32, + int)); + +#ifdef PNG_PROGRESSIVE_READ_SUPPORTED +typedef void (PNGAPI *png_progressive_info_ptr) PNGARG((png_structp, + png_infop)); +typedef void (PNGAPI *png_progressive_end_ptr) PNGARG((png_structp, png_infop)); +typedef void (PNGAPI *png_progressive_row_ptr) PNGARG((png_structp, png_bytep, + png_uint_32, int)); +#endif + +#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \ + defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) +typedef void (PNGAPI *png_user_transform_ptr) PNGARG((png_structp, + png_row_infop, png_bytep)); +#endif + +#ifdef PNG_USER_CHUNKS_SUPPORTED +typedef int (PNGAPI *png_user_chunk_ptr) PNGARG((png_structp, + png_unknown_chunkp)); +#endif +#ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED +typedef void (PNGAPI *png_unknown_chunk_ptr) PNGARG((png_structp)); +#endif +#ifdef PNG_SETJMP_SUPPORTED +/* This must match the function definition in , and the + * application must include this before png.h to obtain the definition + * of jmp_buf. + */ +typedef void (PNGAPI *png_longjmp_ptr) PNGARG((jmp_buf, int)); +#endif + +/* Transform masks for the high-level interface */ +#define PNG_TRANSFORM_IDENTITY 0x0000 /* read and write */ +#define PNG_TRANSFORM_STRIP_16 0x0001 /* read only */ +#define PNG_TRANSFORM_STRIP_ALPHA 0x0002 /* read only */ +#define PNG_TRANSFORM_PACKING 0x0004 /* read and write */ +#define PNG_TRANSFORM_PACKSWAP 0x0008 /* read and write */ +#define PNG_TRANSFORM_EXPAND 0x0010 /* read only */ +#define PNG_TRANSFORM_INVERT_MONO 0x0020 /* read and write */ +#define PNG_TRANSFORM_SHIFT 0x0040 /* read and write */ +#define PNG_TRANSFORM_BGR 0x0080 /* read and write */ +#define PNG_TRANSFORM_SWAP_ALPHA 0x0100 /* read and write */ +#define PNG_TRANSFORM_SWAP_ENDIAN 0x0200 /* read and write */ +#define PNG_TRANSFORM_INVERT_ALPHA 0x0400 /* read and write */ +#define PNG_TRANSFORM_STRIP_FILLER 0x0800 /* write only */ +/* Added to libpng-1.2.34 */ +#define PNG_TRANSFORM_STRIP_FILLER_BEFORE PNG_TRANSFORM_STRIP_FILLER +#define PNG_TRANSFORM_STRIP_FILLER_AFTER 0x1000 /* write only */ +/* Added to libpng-1.4.0 */ +#define PNG_TRANSFORM_GRAY_TO_RGB 0x2000 /* read only */ + +/* Flags for MNG supported features */ +#define PNG_FLAG_MNG_EMPTY_PLTE 0x01 +#define PNG_FLAG_MNG_FILTER_64 0x04 +#define PNG_ALL_MNG_FEATURES 0x05 + +typedef png_voidp (*png_malloc_ptr) PNGARG((png_structp, png_alloc_size_t)); +typedef void (*png_free_ptr) PNGARG((png_structp, png_voidp)); + +/* The structure that holds the information to read and write PNG files. + * The only people who need to care about what is inside of this are the + * people who will be modifying the library for their own special needs. + * It should NOT be accessed directly by an application, except to store + * the jmp_buf. + */ + +struct png_struct_def +{ +#ifdef PNG_SETJMP_SUPPORTED + jmp_buf jmpbuf PNG_DEPSTRUCT; /* used in png_error */ + png_longjmp_ptr longjmp_fn PNG_DEPSTRUCT;/* setjmp non-local goto + function. */ +#endif + png_error_ptr error_fn PNG_DEPSTRUCT; /* function for printing + errors and aborting */ + png_error_ptr warning_fn PNG_DEPSTRUCT; /* function for printing + warnings */ + png_voidp error_ptr PNG_DEPSTRUCT; /* user supplied struct for + error functions */ + png_rw_ptr write_data_fn PNG_DEPSTRUCT; /* function for writing + output data */ + png_rw_ptr read_data_fn PNG_DEPSTRUCT; /* function for reading + input data */ + png_voidp io_ptr PNG_DEPSTRUCT; /* ptr to application struct + for I/O functions */ + +#ifdef PNG_READ_USER_TRANSFORM_SUPPORTED + png_user_transform_ptr read_user_transform_fn PNG_DEPSTRUCT; /* user read + transform */ +#endif + +#ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED + png_user_transform_ptr write_user_transform_fn PNG_DEPSTRUCT; /* user write + transform */ +#endif + +/* These were added in libpng-1.0.2 */ +#ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED +#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \ + defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) + png_voidp user_transform_ptr PNG_DEPSTRUCT; /* user supplied struct + for user transform */ + png_byte user_transform_depth PNG_DEPSTRUCT; /* bit depth of user + transformed pixels */ + png_byte user_transform_channels PNG_DEPSTRUCT; /* channels in user + transformed pixels */ +#endif +#endif + + png_uint_32 mode PNG_DEPSTRUCT; /* tells us where we are in + the PNG file */ + png_uint_32 flags PNG_DEPSTRUCT; /* flags indicating various + things to libpng */ + png_uint_32 transformations PNG_DEPSTRUCT; /* which transformations + to perform */ + + z_stream zstream PNG_DEPSTRUCT; /* pointer to decompression + structure (below) */ + png_bytep zbuf PNG_DEPSTRUCT; /* buffer for zlib */ + png_size_t zbuf_size PNG_DEPSTRUCT; /* size of zbuf */ + int zlib_level PNG_DEPSTRUCT; /* holds zlib compression level */ + int zlib_method PNG_DEPSTRUCT; /* holds zlib compression method */ + int zlib_window_bits PNG_DEPSTRUCT; /* holds zlib compression window + bits */ + int zlib_mem_level PNG_DEPSTRUCT; /* holds zlib compression memory + level */ + int zlib_strategy PNG_DEPSTRUCT; /* holds zlib compression + strategy */ + + png_uint_32 width PNG_DEPSTRUCT; /* width of image in pixels */ + png_uint_32 height PNG_DEPSTRUCT; /* height of image in pixels */ + png_uint_32 num_rows PNG_DEPSTRUCT; /* number of rows in current pass */ + png_uint_32 usr_width PNG_DEPSTRUCT; /* width of row at start of write */ + png_size_t rowbytes PNG_DEPSTRUCT; /* size of row in bytes */ +#if 0 /* Replaced with the following in libpng-1.4.1 */ + png_size_t irowbytes PNG_DEPSTRUCT; +#endif +/* Added in libpng-1.4.1 */ +#ifdef PNG_USER_LIMITS_SUPPORTED + /* Total memory that a zTXt, sPLT, iTXt, iCCP, or unknown chunk + * can occupy when decompressed. 0 means unlimited. + * We will change the typedef from png_size_t to png_alloc_size_t + * in libpng-1.6.0 + */ + png_alloc_size_t user_chunk_malloc_max PNG_DEPSTRUCT; +#endif + png_uint_32 iwidth PNG_DEPSTRUCT; /* width of current interlaced + row in pixels */ + png_uint_32 row_number PNG_DEPSTRUCT; /* current row in interlace pass */ + png_bytep prev_row PNG_DEPSTRUCT; /* buffer to save previous + (unfiltered) row */ + png_bytep row_buf PNG_DEPSTRUCT; /* buffer to save current + (unfiltered) row */ + png_bytep sub_row PNG_DEPSTRUCT; /* buffer to save "sub" row + when filtering */ + png_bytep up_row PNG_DEPSTRUCT; /* buffer to save "up" row + when filtering */ + png_bytep avg_row PNG_DEPSTRUCT; /* buffer to save "avg" row + when filtering */ + png_bytep paeth_row PNG_DEPSTRUCT; /* buffer to save "Paeth" row + when filtering */ + png_row_info row_info PNG_DEPSTRUCT; /* used for transformation + routines */ + + png_uint_32 idat_size PNG_DEPSTRUCT; /* current IDAT size for read */ + png_uint_32 crc PNG_DEPSTRUCT; /* current chunk CRC value */ + png_colorp palette PNG_DEPSTRUCT; /* palette from the input file */ + png_uint_16 num_palette PNG_DEPSTRUCT; /* number of color entries in + palette */ + png_uint_16 num_trans PNG_DEPSTRUCT; /* number of transparency values */ + png_byte chunk_name[5] PNG_DEPSTRUCT; /* null-terminated name of current + chunk */ + png_byte compression PNG_DEPSTRUCT; /* file compression type + (always 0) */ + png_byte filter PNG_DEPSTRUCT; /* file filter type (always 0) */ + png_byte interlaced PNG_DEPSTRUCT; /* PNG_INTERLACE_NONE, + PNG_INTERLACE_ADAM7 */ + png_byte pass PNG_DEPSTRUCT; /* current interlace pass (0 - 6) */ + png_byte do_filter PNG_DEPSTRUCT; /* row filter flags (see + PNG_FILTER_ below ) */ + png_byte color_type PNG_DEPSTRUCT; /* color type of file */ + png_byte bit_depth PNG_DEPSTRUCT; /* bit depth of file */ + png_byte usr_bit_depth PNG_DEPSTRUCT; /* bit depth of users row */ + png_byte pixel_depth PNG_DEPSTRUCT; /* number of bits per pixel */ + png_byte channels PNG_DEPSTRUCT; /* number of channels in file */ + png_byte usr_channels PNG_DEPSTRUCT; /* channels at start of write */ + png_byte sig_bytes PNG_DEPSTRUCT; /* magic bytes read/written from + start of file */ + +#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED) + png_uint_16 filler PNG_DEPSTRUCT; /* filler bytes for pixel + expansion */ +#endif + +#ifdef PNG_bKGD_SUPPORTED + png_byte background_gamma_type PNG_DEPSTRUCT; +# ifdef PNG_FLOATING_POINT_SUPPORTED + float background_gamma PNG_DEPSTRUCT; +# endif + png_color_16 background PNG_DEPSTRUCT; /* background color in + screen gamma space */ +#ifdef PNG_READ_GAMMA_SUPPORTED + png_color_16 background_1 PNG_DEPSTRUCT; /* background normalized + to gamma 1.0 */ +#endif +#endif /* PNG_bKGD_SUPPORTED */ + +#ifdef PNG_WRITE_FLUSH_SUPPORTED + png_flush_ptr output_flush_fn PNG_DEPSTRUCT; /* Function for flushing + output */ + png_uint_32 flush_dist PNG_DEPSTRUCT; /* how many rows apart to flush, + 0 - no flush */ + png_uint_32 flush_rows PNG_DEPSTRUCT; /* number of rows written since + last flush */ +#endif + +#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) + int gamma_shift PNG_DEPSTRUCT; /* number of "insignificant" bits + 16-bit gamma */ +#ifdef PNG_FLOATING_POINT_SUPPORTED + float gamma PNG_DEPSTRUCT; /* file gamma value */ + float screen_gamma PNG_DEPSTRUCT; /* screen gamma value + (display_exponent) */ +#endif +#endif + +#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) + png_bytep gamma_table PNG_DEPSTRUCT; /* gamma table for 8-bit + depth files */ + png_bytep gamma_from_1 PNG_DEPSTRUCT; /* converts from 1.0 to screen */ + png_bytep gamma_to_1 PNG_DEPSTRUCT; /* converts from file to 1.0 */ + png_uint_16pp gamma_16_table PNG_DEPSTRUCT; /* gamma table for 16-bit + depth files */ + png_uint_16pp gamma_16_from_1 PNG_DEPSTRUCT; /* converts from 1.0 to + screen */ + png_uint_16pp gamma_16_to_1 PNG_DEPSTRUCT; /* converts from file to 1.0 */ +#endif + +#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_sBIT_SUPPORTED) + png_color_8 sig_bit PNG_DEPSTRUCT; /* significant bits in each + available channel */ +#endif + +#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED) + png_color_8 shift PNG_DEPSTRUCT; /* shift for significant bit + tranformation */ +#endif + +#if defined(PNG_tRNS_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) \ + || defined(PNG_READ_EXPAND_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) + png_bytep trans_alpha PNG_DEPSTRUCT; /* alpha values for + paletted files */ + png_color_16 trans_color PNG_DEPSTRUCT; /* transparent color for + non-paletted files */ +#endif + + png_read_status_ptr read_row_fn PNG_DEPSTRUCT; /* called after each + row is decoded */ + png_write_status_ptr write_row_fn PNG_DEPSTRUCT; /* called after each + row is encoded */ +#ifdef PNG_PROGRESSIVE_READ_SUPPORTED + png_progressive_info_ptr info_fn PNG_DEPSTRUCT; /* called after header + data fully read */ + png_progressive_row_ptr row_fn PNG_DEPSTRUCT; /* called after each + prog. row is decoded */ + png_progressive_end_ptr end_fn PNG_DEPSTRUCT; /* called after image + is complete */ + png_bytep save_buffer_ptr PNG_DEPSTRUCT; /* current location in + save_buffer */ + png_bytep save_buffer PNG_DEPSTRUCT; /* buffer for previously + read data */ + png_bytep current_buffer_ptr PNG_DEPSTRUCT; /* current location in + current_buffer */ + png_bytep current_buffer PNG_DEPSTRUCT; /* buffer for recently + used data */ + png_uint_32 push_length PNG_DEPSTRUCT; /* size of current input + chunk */ + png_uint_32 skip_length PNG_DEPSTRUCT; /* bytes to skip in + input data */ + png_size_t save_buffer_size PNG_DEPSTRUCT; /* amount of data now + in save_buffer */ + png_size_t save_buffer_max PNG_DEPSTRUCT; /* total size of + save_buffer */ + png_size_t buffer_size PNG_DEPSTRUCT; /* total amount of + available input data */ + png_size_t current_buffer_size PNG_DEPSTRUCT; /* amount of data now + in current_buffer */ + int process_mode PNG_DEPSTRUCT; /* what push library + is currently doing */ + int cur_palette PNG_DEPSTRUCT; /* current push library + palette index */ + +# ifdef PNG_TEXT_SUPPORTED + png_size_t current_text_size PNG_DEPSTRUCT; /* current size of + text input data */ + png_size_t current_text_left PNG_DEPSTRUCT; /* how much text left + to read in input */ + png_charp current_text PNG_DEPSTRUCT; /* current text chunk + buffer */ + png_charp current_text_ptr PNG_DEPSTRUCT; /* current location + in current_text */ +# endif /* PNG_PROGRESSIVE_READ_SUPPORTED && PNG_TEXT_SUPPORTED */ + +#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */ + +#if defined(__TURBOC__) && !defined(_Windows) && !defined(__FLAT__) +/* For the Borland special 64K segment handler */ + png_bytepp offset_table_ptr PNG_DEPSTRUCT; + png_bytep offset_table PNG_DEPSTRUCT; + png_uint_16 offset_table_number PNG_DEPSTRUCT; + png_uint_16 offset_table_count PNG_DEPSTRUCT; + png_uint_16 offset_table_count_free PNG_DEPSTRUCT; +#endif + +#ifdef PNG_READ_QUANTIZE_SUPPORTED + png_bytep palette_lookup PNG_DEPSTRUCT; /* lookup table for quantizing */ + png_bytep quantize_index PNG_DEPSTRUCT; /* index translation for palette + files */ +#endif + +#if defined(PNG_READ_QUANTIZE_SUPPORTED) || defined(PNG_hIST_SUPPORTED) + png_uint_16p hist PNG_DEPSTRUCT; /* histogram */ +#endif + +#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED + png_byte heuristic_method PNG_DEPSTRUCT; /* heuristic for row + filter selection */ + png_byte num_prev_filters PNG_DEPSTRUCT; /* number of weights + for previous rows */ + png_bytep prev_filters PNG_DEPSTRUCT; /* filter type(s) of + previous row(s) */ + png_uint_16p filter_weights PNG_DEPSTRUCT; /* weight(s) for previous + line(s) */ + png_uint_16p inv_filter_weights PNG_DEPSTRUCT; /* 1/weight(s) for + previous line(s) */ + png_uint_16p filter_costs PNG_DEPSTRUCT; /* relative filter + calculation cost */ + png_uint_16p inv_filter_costs PNG_DEPSTRUCT; /* 1/relative filter + calculation cost */ +#endif + +#ifdef PNG_TIME_RFC1123_SUPPORTED + png_charp time_buffer PNG_DEPSTRUCT; /* String to hold RFC 1123 time text */ +#endif + +/* New members added in libpng-1.0.6 */ + + png_uint_32 free_me PNG_DEPSTRUCT; /* flags items libpng is + responsible for freeing */ + +#ifdef PNG_USER_CHUNKS_SUPPORTED + png_voidp user_chunk_ptr PNG_DEPSTRUCT; + png_user_chunk_ptr read_user_chunk_fn PNG_DEPSTRUCT; /* user read + chunk handler */ +#endif + +#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED + int num_chunk_list PNG_DEPSTRUCT; + png_bytep chunk_list PNG_DEPSTRUCT; +#endif + +/* New members added in libpng-1.0.3 */ +#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED + png_byte rgb_to_gray_status PNG_DEPSTRUCT; + /* These were changed from png_byte in libpng-1.0.6 */ + png_uint_16 rgb_to_gray_red_coeff PNG_DEPSTRUCT; + png_uint_16 rgb_to_gray_green_coeff PNG_DEPSTRUCT; + png_uint_16 rgb_to_gray_blue_coeff PNG_DEPSTRUCT; +#endif + +/* New member added in libpng-1.0.4 (renamed in 1.0.9) */ +#if defined(PNG_MNG_FEATURES_SUPPORTED) || \ + defined(PNG_READ_EMPTY_PLTE_SUPPORTED) || \ + defined(PNG_WRITE_EMPTY_PLTE_SUPPORTED) +/* Changed from png_byte to png_uint_32 at version 1.2.0 */ + png_uint_32 mng_features_permitted PNG_DEPSTRUCT; +#endif + +/* New member added in libpng-1.0.7 */ +#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) + png_fixed_point int_gamma PNG_DEPSTRUCT; +#endif + +/* New member added in libpng-1.0.9, ifdef'ed out in 1.0.12, enabled in 1.2.0 */ +#ifdef PNG_MNG_FEATURES_SUPPORTED + png_byte filter_type PNG_DEPSTRUCT; +#endif + +/* New members added in libpng-1.2.0 */ + +/* New members added in libpng-1.0.2 but first enabled by default in 1.2.0 */ +#ifdef PNG_USER_MEM_SUPPORTED + png_voidp mem_ptr PNG_DEPSTRUCT; /* user supplied struct for + mem functions */ + png_malloc_ptr malloc_fn PNG_DEPSTRUCT; /* function for + allocating memory */ + png_free_ptr free_fn PNG_DEPSTRUCT; /* function for + freeing memory */ +#endif + +/* New member added in libpng-1.0.13 and 1.2.0 */ + png_bytep big_row_buf PNG_DEPSTRUCT; /* buffer to save current + (unfiltered) row */ + +#ifdef PNG_READ_QUANTIZE_SUPPORTED +/* The following three members were added at version 1.0.14 and 1.2.4 */ + png_bytep quantize_sort PNG_DEPSTRUCT; /* working sort array */ + png_bytep index_to_palette PNG_DEPSTRUCT; /* where the original + index currently is + in the palette */ + png_bytep palette_to_index PNG_DEPSTRUCT; /* which original index + points to this + palette color */ +#endif + +/* New members added in libpng-1.0.16 and 1.2.6 */ + png_byte compression_type PNG_DEPSTRUCT; + +#ifdef PNG_USER_LIMITS_SUPPORTED + png_uint_32 user_width_max PNG_DEPSTRUCT; + png_uint_32 user_height_max PNG_DEPSTRUCT; + /* Added in libpng-1.4.0: Total number of sPLT, text, and unknown + * chunks that can be stored (0 means unlimited). + */ + png_uint_32 user_chunk_cache_max PNG_DEPSTRUCT; +#endif + +/* New member added in libpng-1.0.25 and 1.2.17 */ +#ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED + /* Storage for unknown chunk that the library doesn't recognize. */ + png_unknown_chunk unknown_chunk PNG_DEPSTRUCT; +#endif + +/* New members added in libpng-1.2.26 */ + png_uint_32 old_big_row_buf_size PNG_DEPSTRUCT; + png_uint_32 old_prev_row_size PNG_DEPSTRUCT; + +/* New member added in libpng-1.2.30 */ + png_charp chunkdata PNG_DEPSTRUCT; /* buffer for reading chunk data */ + +#ifdef PNG_IO_STATE_SUPPORTED +/* New member added in libpng-1.4.0 */ + png_uint_32 io_state PNG_DEPSTRUCT; +#endif +}; + + +/* This triggers a compiler error in png.c, if png.c and png.h + * do not agree upon the version number. + */ +typedef png_structp version_1_4_4; + +typedef png_struct FAR * FAR * png_structpp; + +/* Here are the function definitions most commonly used. This is not + * the place to find out how to use libpng. See libpng.txt for the + * full explanation, see example.c for the summary. This just provides + * a simple one line description of the use of each function. + */ + +/* Returns the version number of the library */ +PNG_EXPORT(png_uint_32,png_access_version_number) PNGARG((void)); + +/* Tell lib we have already handled the first magic bytes. + * Handling more than 8 bytes from the beginning of the file is an error. + */ +PNG_EXPORT(void,png_set_sig_bytes) PNGARG((png_structp png_ptr, + int num_bytes)); + +/* Check sig[start] through sig[start + num_to_check - 1] to see if it's a + * PNG file. Returns zero if the supplied bytes match the 8-byte PNG + * signature, and non-zero otherwise. Having num_to_check == 0 or + * start > 7 will always fail (ie return non-zero). + */ +PNG_EXPORT(int,png_sig_cmp) PNGARG((png_bytep sig, png_size_t start, + png_size_t num_to_check)); + +/* Simple signature checking function. This is the same as calling + * png_check_sig(sig, n) := !png_sig_cmp(sig, 0, n). + */ +#define png_check_sig(sig,n) !png_sig_cmp((sig), 0, (n)) + +/* Allocate and initialize png_ptr struct for reading, and any other memory. */ +PNG_EXPORT(png_structp,png_create_read_struct) + PNGARG((png_const_charp user_png_ver, png_voidp error_ptr, + png_error_ptr error_fn, png_error_ptr warn_fn)) PNG_ALLOCATED; + +/* Allocate and initialize png_ptr struct for writing, and any other memory */ +PNG_EXPORT(png_structp,png_create_write_struct) + PNGARG((png_const_charp user_png_ver, png_voidp error_ptr, + png_error_ptr error_fn, png_error_ptr warn_fn)) PNG_ALLOCATED; + +PNG_EXPORT(png_size_t,png_get_compression_buffer_size) + PNGARG((png_structp png_ptr)); + +PNG_EXPORT(void,png_set_compression_buffer_size) + PNGARG((png_structp png_ptr, png_size_t size)); + +/* Moved from pngconf.h in 1.4.0 and modified to ensure setjmp/longjmp + * match up. + */ +#ifdef PNG_SETJMP_SUPPORTED +/* This function returns the jmp_buf built in to *png_ptr. It must be + * supplied with an appropriate 'longjmp' function to use on that jmp_buf + * unless the default error function is overridden in which case NULL is + * acceptable. The size of the jmp_buf is checked against the actual size + * allocated by the library - the call will return NULL on a mismatch + * indicating an ABI mismatch. + */ +PNG_EXPORT(jmp_buf*, png_set_longjmp_fn) + PNGARG((png_structp png_ptr, png_longjmp_ptr longjmp_fn, size_t + jmp_buf_size)); +# define png_jmpbuf(png_ptr) \ + (*png_set_longjmp_fn((png_ptr), longjmp, sizeof (jmp_buf))) +#else +# define png_jmpbuf(png_ptr) \ + (LIBPNG_WAS_COMPILED_WITH__PNG_NO_SETJMP) +#endif + +#ifdef PNG_READ_SUPPORTED +/* Reset the compression stream */ +PNG_EXPORT(int,png_reset_zstream) PNGARG((png_structp png_ptr)); +#endif + +/* New functions added in libpng-1.0.2 (not enabled by default until 1.2.0) */ +#ifdef PNG_USER_MEM_SUPPORTED +PNG_EXPORT(png_structp,png_create_read_struct_2) + PNGARG((png_const_charp user_png_ver, png_voidp error_ptr, + png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr, + png_malloc_ptr malloc_fn, png_free_ptr free_fn)) PNG_ALLOCATED; +PNG_EXPORT(png_structp,png_create_write_struct_2) + PNGARG((png_const_charp user_png_ver, png_voidp error_ptr, + png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr, + png_malloc_ptr malloc_fn, png_free_ptr free_fn)) PNG_ALLOCATED; +#endif + +/* Write the PNG file signature. */ +PNG_EXPORT(void,png_write_sig) PNGARG((png_structp png_ptr)); + +/* Write a PNG chunk - size, type, (optional) data, CRC. */ +PNG_EXPORT(void,png_write_chunk) PNGARG((png_structp png_ptr, + png_bytep chunk_name, png_bytep data, png_size_t length)); + +/* Write the start of a PNG chunk - length and chunk name. */ +PNG_EXPORT(void,png_write_chunk_start) PNGARG((png_structp png_ptr, + png_bytep chunk_name, png_uint_32 length)); + +/* Write the data of a PNG chunk started with png_write_chunk_start(). */ +PNG_EXPORT(void,png_write_chunk_data) PNGARG((png_structp png_ptr, + png_bytep data, png_size_t length)); + +/* Finish a chunk started with png_write_chunk_start() (includes CRC). */ +PNG_EXPORT(void,png_write_chunk_end) PNGARG((png_structp png_ptr)); + +/* Allocate and initialize the info structure */ +PNG_EXPORT(png_infop,png_create_info_struct) + PNGARG((png_structp png_ptr)) PNG_ALLOCATED; + +PNG_EXPORT(void,png_info_init_3) PNGARG((png_infopp info_ptr, + png_size_t png_info_struct_size)); + +/* Writes all the PNG information before the image. */ +PNG_EXPORT(void,png_write_info_before_PLTE) PNGARG((png_structp png_ptr, + png_infop info_ptr)); +PNG_EXPORT(void,png_write_info) PNGARG((png_structp png_ptr, + png_infop info_ptr)); + +#ifdef PNG_SEQUENTIAL_READ_SUPPORTED +/* Read the information before the actual image data. */ +PNG_EXPORT(void,png_read_info) PNGARG((png_structp png_ptr, + png_infop info_ptr)); +#endif + +#ifdef PNG_TIME_RFC1123_SUPPORTED +PNG_EXPORT(png_charp,png_convert_to_rfc1123) + PNGARG((png_structp png_ptr, png_timep ptime)); +#endif + +#ifdef PNG_CONVERT_tIME_SUPPORTED +/* Convert from a struct tm to png_time */ +PNG_EXPORT(void,png_convert_from_struct_tm) PNGARG((png_timep ptime, + struct tm FAR * ttime)); + +/* Convert from time_t to png_time. Uses gmtime() */ +PNG_EXPORT(void,png_convert_from_time_t) PNGARG((png_timep ptime, + time_t ttime)); +#endif /* PNG_CONVERT_tIME_SUPPORTED */ + +#ifdef PNG_READ_EXPAND_SUPPORTED +/* Expand data to 24-bit RGB, or 8-bit grayscale, with alpha if available. */ +PNG_EXPORT(void,png_set_expand) PNGARG((png_structp png_ptr)); +PNG_EXPORT(void,png_set_expand_gray_1_2_4_to_8) PNGARG((png_structp + png_ptr)); +PNG_EXPORT(void,png_set_palette_to_rgb) PNGARG((png_structp png_ptr)); +PNG_EXPORT(void,png_set_tRNS_to_alpha) PNGARG((png_structp png_ptr)); +#endif + +#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED) +/* Use blue, green, red order for pixels. */ +PNG_EXPORT(void,png_set_bgr) PNGARG((png_structp png_ptr)); +#endif + +#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED +/* Expand the grayscale to 24-bit RGB if necessary. */ +PNG_EXPORT(void,png_set_gray_to_rgb) PNGARG((png_structp png_ptr)); +#endif + +#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED +/* Reduce RGB to grayscale. */ +#ifdef PNG_FLOATING_POINT_SUPPORTED +PNG_EXPORT(void,png_set_rgb_to_gray) PNGARG((png_structp png_ptr, + int error_action, double red, double green )); +#endif +PNG_EXPORT(void,png_set_rgb_to_gray_fixed) PNGARG((png_structp png_ptr, + int error_action, png_fixed_point red, png_fixed_point green )); +PNG_EXPORT(png_byte,png_get_rgb_to_gray_status) PNGARG((png_structp + png_ptr)); +#endif + +PNG_EXPORT(void,png_build_grayscale_palette) PNGARG((int bit_depth, + png_colorp palette)); + +#ifdef PNG_READ_STRIP_ALPHA_SUPPORTED +PNG_EXPORT(void,png_set_strip_alpha) PNGARG((png_structp png_ptr)); +#endif + +#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) || \ + defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED) +PNG_EXPORT(void,png_set_swap_alpha) PNGARG((png_structp png_ptr)); +#endif + +#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) || \ + defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED) +PNG_EXPORT(void,png_set_invert_alpha) PNGARG((png_structp png_ptr)); +#endif + +#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED) +/* Add a filler byte to 8-bit Gray or 24-bit RGB images. */ +PNG_EXPORT(void,png_set_filler) PNGARG((png_structp png_ptr, + png_uint_32 filler, int flags)); +/* The values of the PNG_FILLER_ defines should NOT be changed */ +#define PNG_FILLER_BEFORE 0 +#define PNG_FILLER_AFTER 1 +/* Add an alpha byte to 8-bit Gray or 24-bit RGB images. */ +PNG_EXPORT(void,png_set_add_alpha) PNGARG((png_structp png_ptr, + png_uint_32 filler, int flags)); +#endif /* PNG_READ_FILLER_SUPPORTED || PNG_WRITE_FILLER_SUPPORTED */ + +#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED) +/* Swap bytes in 16-bit depth files. */ +PNG_EXPORT(void,png_set_swap) PNGARG((png_structp png_ptr)); +#endif + +#if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED) +/* Use 1 byte per pixel in 1, 2, or 4-bit depth files. */ +PNG_EXPORT(void,png_set_packing) PNGARG((png_structp png_ptr)); +#endif + +#if defined(PNG_READ_PACKSWAP_SUPPORTED) || \ + defined(PNG_WRITE_PACKSWAP_SUPPORTED) +/* Swap packing order of pixels in bytes. */ +PNG_EXPORT(void,png_set_packswap) PNGARG((png_structp png_ptr)); +#endif + +#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED) +/* Converts files to legal bit depths. */ +PNG_EXPORT(void,png_set_shift) PNGARG((png_structp png_ptr, + png_color_8p true_bits)); +#endif + +#if defined(PNG_READ_INTERLACING_SUPPORTED) || \ + defined(PNG_WRITE_INTERLACING_SUPPORTED) +/* Have the code handle the interlacing. Returns the number of passes. */ +PNG_EXPORT(int,png_set_interlace_handling) PNGARG((png_structp png_ptr)); +#endif + +#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED) +/* Invert monochrome files */ +PNG_EXPORT(void,png_set_invert_mono) PNGARG((png_structp png_ptr)); +#endif + +#ifdef PNG_READ_BACKGROUND_SUPPORTED +/* Handle alpha and tRNS by replacing with a background color. */ +#ifdef PNG_FLOATING_POINT_SUPPORTED +PNG_EXPORT(void,png_set_background) PNGARG((png_structp png_ptr, + png_color_16p background_color, int background_gamma_code, + int need_expand, double background_gamma)); +#endif +#define PNG_BACKGROUND_GAMMA_UNKNOWN 0 +#define PNG_BACKGROUND_GAMMA_SCREEN 1 +#define PNG_BACKGROUND_GAMMA_FILE 2 +#define PNG_BACKGROUND_GAMMA_UNIQUE 3 +#endif + +#ifdef PNG_READ_16_TO_8_SUPPORTED +/* Strip the second byte of information from a 16-bit depth file. */ +PNG_EXPORT(void,png_set_strip_16) PNGARG((png_structp png_ptr)); +#endif + +#ifdef PNG_READ_QUANTIZE_SUPPORTED +/* Turn on quantizing, and reduce the palette to the number of colors + * available. Prior to libpng-1.4.2, this was png_set_dither(). + */ +PNG_EXPORT(void,png_set_quantize) PNGARG((png_structp png_ptr, + png_colorp palette, int num_palette, int maximum_colors, + png_uint_16p histogram, int full_quantize)); +#endif +/* This migration aid will be removed from libpng-1.5.0 */ +#define png_set_dither png_set_quantize + +#ifdef PNG_READ_GAMMA_SUPPORTED +/* Handle gamma correction. Screen_gamma=(display_exponent) */ +#ifdef PNG_FLOATING_POINT_SUPPORTED +PNG_EXPORT(void,png_set_gamma) PNGARG((png_structp png_ptr, + double screen_gamma, double default_file_gamma)); +#endif +#endif + + +#ifdef PNG_WRITE_FLUSH_SUPPORTED +/* Set how many lines between output flushes - 0 for no flushing */ +PNG_EXPORT(void,png_set_flush) PNGARG((png_structp png_ptr, int nrows)); +/* Flush the current PNG output buffer */ +PNG_EXPORT(void,png_write_flush) PNGARG((png_structp png_ptr)); +#endif + +/* Optional update palette with requested transformations */ +PNG_EXPORT(void,png_start_read_image) PNGARG((png_structp png_ptr)); + +/* Optional call to update the users info structure */ +PNG_EXPORT(void,png_read_update_info) PNGARG((png_structp png_ptr, + png_infop info_ptr)); + +#ifdef PNG_SEQUENTIAL_READ_SUPPORTED +/* Read one or more rows of image data. */ +PNG_EXPORT(void,png_read_rows) PNGARG((png_structp png_ptr, + png_bytepp row, png_bytepp display_row, png_uint_32 num_rows)); +#endif + +#ifdef PNG_SEQUENTIAL_READ_SUPPORTED +/* Read a row of data. */ +PNG_EXPORT(void,png_read_row) PNGARG((png_structp png_ptr, + png_bytep row, + png_bytep display_row)); +#endif + +#ifdef PNG_SEQUENTIAL_READ_SUPPORTED +/* Read the whole image into memory at once. */ +PNG_EXPORT(void,png_read_image) PNGARG((png_structp png_ptr, + png_bytepp image)); +#endif + +/* Write a row of image data */ +PNG_EXPORT(void,png_write_row) PNGARG((png_structp png_ptr, + png_bytep row)); + +/* Write a few rows of image data */ +PNG_EXPORT(void,png_write_rows) PNGARG((png_structp png_ptr, + png_bytepp row, png_uint_32 num_rows)); + +/* Write the image data */ +PNG_EXPORT(void,png_write_image) PNGARG((png_structp png_ptr, + png_bytepp image)); + +/* Write the end of the PNG file. */ +PNG_EXPORT(void,png_write_end) PNGARG((png_structp png_ptr, + png_infop info_ptr)); + +#ifdef PNG_SEQUENTIAL_READ_SUPPORTED +/* Read the end of the PNG file. */ +PNG_EXPORT(void,png_read_end) PNGARG((png_structp png_ptr, + png_infop info_ptr)); +#endif + +/* Free any memory associated with the png_info_struct */ +PNG_EXPORT(void,png_destroy_info_struct) PNGARG((png_structp png_ptr, + png_infopp info_ptr_ptr)); + +/* Free any memory associated with the png_struct and the png_info_structs */ +PNG_EXPORT(void,png_destroy_read_struct) PNGARG((png_structpp + png_ptr_ptr, png_infopp info_ptr_ptr, png_infopp end_info_ptr_ptr)); + +/* Free any memory associated with the png_struct and the png_info_structs */ +PNG_EXPORT(void,png_destroy_write_struct) + PNGARG((png_structpp png_ptr_ptr, png_infopp info_ptr_ptr)); + +/* Set the libpng method of handling chunk CRC errors */ +PNG_EXPORT(void,png_set_crc_action) PNGARG((png_structp png_ptr, + int crit_action, int ancil_action)); + +/* Values for png_set_crc_action() to say how to handle CRC errors in + * ancillary and critical chunks, and whether to use the data contained + * therein. Note that it is impossible to "discard" data in a critical + * chunk. For versions prior to 0.90, the action was always error/quit, + * whereas in version 0.90 and later, the action for CRC errors in ancillary + * chunks is warn/discard. These values should NOT be changed. + * + * value action:critical action:ancillary + */ +#define PNG_CRC_DEFAULT 0 /* error/quit warn/discard data */ +#define PNG_CRC_ERROR_QUIT 1 /* error/quit error/quit */ +#define PNG_CRC_WARN_DISCARD 2 /* (INVALID) warn/discard data */ +#define PNG_CRC_WARN_USE 3 /* warn/use data warn/use data */ +#define PNG_CRC_QUIET_USE 4 /* quiet/use data quiet/use data */ +#define PNG_CRC_NO_CHANGE 5 /* use current value use current value */ + +/* These functions give the user control over the scan-line filtering in + * libpng and the compression methods used by zlib. These functions are + * mainly useful for testing, as the defaults should work with most users. + * Those users who are tight on memory or want faster performance at the + * expense of compression can modify them. See the compression library + * header file (zlib.h) for an explination of the compression functions. + */ + +/* Set the filtering method(s) used by libpng. Currently, the only valid + * value for "method" is 0. + */ +PNG_EXPORT(void,png_set_filter) PNGARG((png_structp png_ptr, int method, + int filters)); + +/* Flags for png_set_filter() to say which filters to use. The flags + * are chosen so that they don't conflict with real filter types + * below, in case they are supplied instead of the #defined constants. + * These values should NOT be changed. + */ +#define PNG_NO_FILTERS 0x00 +#define PNG_FILTER_NONE 0x08 +#define PNG_FILTER_SUB 0x10 +#define PNG_FILTER_UP 0x20 +#define PNG_FILTER_AVG 0x40 +#define PNG_FILTER_PAETH 0x80 +#define PNG_ALL_FILTERS (PNG_FILTER_NONE | PNG_FILTER_SUB | PNG_FILTER_UP | \ + PNG_FILTER_AVG | PNG_FILTER_PAETH) + +/* Filter values (not flags) - used in pngwrite.c, pngwutil.c for now. + * These defines should NOT be changed. + */ +#define PNG_FILTER_VALUE_NONE 0 +#define PNG_FILTER_VALUE_SUB 1 +#define PNG_FILTER_VALUE_UP 2 +#define PNG_FILTER_VALUE_AVG 3 +#define PNG_FILTER_VALUE_PAETH 4 +#define PNG_FILTER_VALUE_LAST 5 + +#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED /* EXPERIMENTAL */ +/* The "heuristic_method" is given by one of the PNG_FILTER_HEURISTIC_ + * defines, either the default (minimum-sum-of-absolute-differences), or + * the experimental method (weighted-minimum-sum-of-absolute-differences). + * + * Weights are factors >= 1.0, indicating how important it is to keep the + * filter type consistent between rows. Larger numbers mean the current + * filter is that many times as likely to be the same as the "num_weights" + * previous filters. This is cumulative for each previous row with a weight. + * There needs to be "num_weights" values in "filter_weights", or it can be + * NULL if the weights aren't being specified. Weights have no influence on + * the selection of the first row filter. Well chosen weights can (in theory) + * improve the compression for a given image. + * + * Costs are factors >= 1.0 indicating the relative decoding costs of a + * filter type. Higher costs indicate more decoding expense, and are + * therefore less likely to be selected over a filter with lower computational + * costs. There needs to be a value in "filter_costs" for each valid filter + * type (given by PNG_FILTER_VALUE_LAST), or it can be NULL if you aren't + * setting the costs. Costs try to improve the speed of decompression without + * unduly increasing the compressed image size. + * + * A negative weight or cost indicates the default value is to be used, and + * values in the range [0.0, 1.0) indicate the value is to remain unchanged. + * The default values for both weights and costs are currently 1.0, but may + * change if good general weighting/cost heuristics can be found. If both + * the weights and costs are set to 1.0, this degenerates the WEIGHTED method + * to the UNWEIGHTED method, but with added encoding time/computation. + */ +#ifdef PNG_FLOATING_POINT_SUPPORTED +PNG_EXPORT(void,png_set_filter_heuristics) PNGARG((png_structp png_ptr, + int heuristic_method, int num_weights, png_doublep filter_weights, + png_doublep filter_costs)); +#endif +#endif /* PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */ + +/* Heuristic used for row filter selection. These defines should NOT be + * changed. + */ +#define PNG_FILTER_HEURISTIC_DEFAULT 0 /* Currently "UNWEIGHTED" */ +#define PNG_FILTER_HEURISTIC_UNWEIGHTED 1 /* Used by libpng < 0.95 */ +#define PNG_FILTER_HEURISTIC_WEIGHTED 2 /* Experimental feature */ +#define PNG_FILTER_HEURISTIC_LAST 3 /* Not a valid value */ + +/* Set the library compression level. Currently, valid values range from + * 0 - 9, corresponding directly to the zlib compression levels 0 - 9 + * (0 - no compression, 9 - "maximal" compression). Note that tests have + * shown that zlib compression levels 3-6 usually perform as well as level 9 + * for PNG images, and do considerably fewer caclulations. In the future, + * these values may not correspond directly to the zlib compression levels. + */ +PNG_EXPORT(void,png_set_compression_level) PNGARG((png_structp png_ptr, + int level)); + +PNG_EXPORT(void,png_set_compression_mem_level) + PNGARG((png_structp png_ptr, int mem_level)); + +PNG_EXPORT(void,png_set_compression_strategy) + PNGARG((png_structp png_ptr, int strategy)); + +PNG_EXPORT(void,png_set_compression_window_bits) + PNGARG((png_structp png_ptr, int window_bits)); + +PNG_EXPORT(void,png_set_compression_method) PNGARG((png_structp png_ptr, + int method)); + +/* These next functions are called for input/output, memory, and error + * handling. They are in the file pngrio.c, pngwio.c, and pngerror.c, + * and call standard C I/O routines such as fread(), fwrite(), and + * fprintf(). These functions can be made to use other I/O routines + * at run time for those applications that need to handle I/O in a + * different manner by calling png_set_???_fn(). See libpng.txt for + * more information. + */ + +#ifdef PNG_STDIO_SUPPORTED +/* Initialize the input/output for the PNG file to the default functions. */ +PNG_EXPORT(void,png_init_io) PNGARG((png_structp png_ptr, + png_FILE_p fp)); +#endif + +/* Replace the (error and abort), and warning functions with user + * supplied functions. If no messages are to be printed you must still + * write and use replacement functions. The replacement error_fn should + * still do a longjmp to the last setjmp location if you are using this + * method of error handling. If error_fn or warning_fn is NULL, the + * default function will be used. + */ + +PNG_EXPORT(void,png_set_error_fn) PNGARG((png_structp png_ptr, + png_voidp error_ptr, png_error_ptr error_fn, png_error_ptr warning_fn)); + +/* Return the user pointer associated with the error functions */ +PNG_EXPORT(png_voidp,png_get_error_ptr) PNGARG((png_structp png_ptr)); + +/* Replace the default data output functions with a user supplied one(s). + * If buffered output is not used, then output_flush_fn can be set to NULL. + * If PNG_WRITE_FLUSH_SUPPORTED is not defined at libpng compile time + * output_flush_fn will be ignored (and thus can be NULL). + * It is probably a mistake to use NULL for output_flush_fn if + * write_data_fn is not also NULL unless you have built libpng with + * PNG_WRITE_FLUSH_SUPPORTED undefined, because in this case libpng's + * default flush function, which uses the standard *FILE structure, will + * be used. + */ +PNG_EXPORT(void,png_set_write_fn) PNGARG((png_structp png_ptr, + png_voidp io_ptr, png_rw_ptr write_data_fn, png_flush_ptr output_flush_fn)); + +/* Replace the default data input function with a user supplied one. */ +PNG_EXPORT(void,png_set_read_fn) PNGARG((png_structp png_ptr, + png_voidp io_ptr, png_rw_ptr read_data_fn)); + +/* Return the user pointer associated with the I/O functions */ +PNG_EXPORT(png_voidp,png_get_io_ptr) PNGARG((png_structp png_ptr)); + +PNG_EXPORT(void,png_set_read_status_fn) PNGARG((png_structp png_ptr, + png_read_status_ptr read_row_fn)); + +PNG_EXPORT(void,png_set_write_status_fn) PNGARG((png_structp png_ptr, + png_write_status_ptr write_row_fn)); + +#ifdef PNG_USER_MEM_SUPPORTED +/* Replace the default memory allocation functions with user supplied one(s). */ +PNG_EXPORT(void,png_set_mem_fn) PNGARG((png_structp png_ptr, + png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn)); +/* Return the user pointer associated with the memory functions */ +PNG_EXPORT(png_voidp,png_get_mem_ptr) PNGARG((png_structp png_ptr)); +#endif + +#ifdef PNG_READ_USER_TRANSFORM_SUPPORTED +PNG_EXPORT(void,png_set_read_user_transform_fn) PNGARG((png_structp + png_ptr, png_user_transform_ptr read_user_transform_fn)); +#endif + +#ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED +PNG_EXPORT(void,png_set_write_user_transform_fn) PNGARG((png_structp + png_ptr, png_user_transform_ptr write_user_transform_fn)); +#endif + +#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \ + defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) +PNG_EXPORT(void,png_set_user_transform_info) PNGARG((png_structp + png_ptr, png_voidp user_transform_ptr, int user_transform_depth, + int user_transform_channels)); +/* Return the user pointer associated with the user transform functions */ +PNG_EXPORT(png_voidp,png_get_user_transform_ptr) + PNGARG((png_structp png_ptr)); +#endif + +#ifdef PNG_USER_CHUNKS_SUPPORTED +PNG_EXPORT(void,png_set_read_user_chunk_fn) PNGARG((png_structp png_ptr, + png_voidp user_chunk_ptr, png_user_chunk_ptr read_user_chunk_fn)); +PNG_EXPORT(png_voidp,png_get_user_chunk_ptr) PNGARG((png_structp + png_ptr)); +#endif + +#ifdef PNG_PROGRESSIVE_READ_SUPPORTED +/* Sets the function callbacks for the push reader, and a pointer to a + * user-defined structure available to the callback functions. + */ +PNG_EXPORT(void,png_set_progressive_read_fn) PNGARG((png_structp png_ptr, + png_voidp progressive_ptr, + png_progressive_info_ptr info_fn, png_progressive_row_ptr row_fn, + png_progressive_end_ptr end_fn)); + +/* Returns the user pointer associated with the push read functions */ +PNG_EXPORT(png_voidp,png_get_progressive_ptr) + PNGARG((png_structp png_ptr)); + +/* Function to be called when data becomes available */ +PNG_EXPORT(void,png_process_data) PNGARG((png_structp png_ptr, + png_infop info_ptr, png_bytep buffer, png_size_t buffer_size)); + +/* Function that combines rows. Not very much different than the + * png_combine_row() call. Is this even used????? + */ +PNG_EXPORT(void,png_progressive_combine_row) PNGARG((png_structp png_ptr, + png_bytep old_row, png_bytep new_row)); +#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */ + +PNG_EXPORT(png_voidp,png_malloc) PNGARG((png_structp png_ptr, + png_alloc_size_t size)) PNG_ALLOCATED; +/* Added at libpng version 1.4.0 */ +PNG_EXPORT(png_voidp,png_calloc) PNGARG((png_structp png_ptr, + png_alloc_size_t size)) PNG_ALLOCATED; + +/* Added at libpng version 1.2.4 */ +PNG_EXPORT(png_voidp,png_malloc_warn) PNGARG((png_structp png_ptr, + png_alloc_size_t size)) PNG_ALLOCATED; + +/* Frees a pointer allocated by png_malloc() */ +PNG_EXPORT(void,png_free) PNGARG((png_structp png_ptr, png_voidp ptr)); + +/* Free data that was allocated internally */ +PNG_EXPORT(void,png_free_data) PNGARG((png_structp png_ptr, + png_infop info_ptr, png_uint_32 free_me, int num)); +/* Reassign responsibility for freeing existing data, whether allocated + * by libpng or by the application */ +PNG_EXPORT(void,png_data_freer) PNGARG((png_structp png_ptr, + png_infop info_ptr, int freer, png_uint_32 mask)); +/* Assignments for png_data_freer */ +#define PNG_DESTROY_WILL_FREE_DATA 1 +#define PNG_SET_WILL_FREE_DATA 1 +#define PNG_USER_WILL_FREE_DATA 2 +/* Flags for png_ptr->free_me and info_ptr->free_me */ +#define PNG_FREE_HIST 0x0008 +#define PNG_FREE_ICCP 0x0010 +#define PNG_FREE_SPLT 0x0020 +#define PNG_FREE_ROWS 0x0040 +#define PNG_FREE_PCAL 0x0080 +#define PNG_FREE_SCAL 0x0100 +#define PNG_FREE_UNKN 0x0200 +#define PNG_FREE_LIST 0x0400 +#define PNG_FREE_PLTE 0x1000 +#define PNG_FREE_TRNS 0x2000 +#define PNG_FREE_TEXT 0x4000 +#define PNG_FREE_ALL 0x7fff +#define PNG_FREE_MUL 0x4220 /* PNG_FREE_SPLT|PNG_FREE_TEXT|PNG_FREE_UNKN */ + +#ifdef PNG_USER_MEM_SUPPORTED +PNG_EXPORT(png_voidp,png_malloc_default) PNGARG((png_structp png_ptr, + png_alloc_size_t size)) PNG_ALLOCATED; +PNG_EXPORT(void,png_free_default) PNGARG((png_structp png_ptr, + png_voidp ptr)); +#endif + +#ifndef PNG_NO_ERROR_TEXT +/* Fatal error in PNG image of libpng - can't continue */ +PNG_EXPORT(void,png_error) PNGARG((png_structp png_ptr, + png_const_charp error_message)) PNG_NORETURN; + +/* The same, but the chunk name is prepended to the error string. */ +PNG_EXPORT(void,png_chunk_error) PNGARG((png_structp png_ptr, + png_const_charp error_message)) PNG_NORETURN; + +#else +/* Fatal error in PNG image of libpng - can't continue */ +PNG_EXPORT(void,png_err) PNGARG((png_structp png_ptr)) PNG_NORETURN; +#endif + +/* Non-fatal error in libpng. Can continue, but may have a problem. */ +PNG_EXPORT(void,png_warning) PNGARG((png_structp png_ptr, + png_const_charp warning_message)); + +/* Non-fatal error in libpng, chunk name is prepended to message. */ +PNG_EXPORT(void,png_chunk_warning) PNGARG((png_structp png_ptr, + png_const_charp warning_message)); + +#ifdef PNG_BENIGN_ERRORS_SUPPORTED +/* Benign error in libpng. Can continue, but may have a problem. + * User can choose whether to handle as a fatal error or as a warning. */ +PNG_EXPORT(void,png_benign_error) PNGARG((png_structp png_ptr, + png_const_charp warning_message)); + +/* Same, chunk name is prepended to message. */ +PNG_EXPORT(void,png_chunk_benign_error) PNGARG((png_structp png_ptr, + png_const_charp warning_message)); + +PNG_EXPORT(void,png_set_benign_errors) PNGARG((png_structp + png_ptr, int allowed)); +#endif + +/* The png_set_ functions are for storing values in the png_info_struct. + * Similarly, the png_get_ calls are used to read values from the + * png_info_struct, either storing the parameters in the passed variables, or + * setting pointers into the png_info_struct where the data is stored. The + * png_get_ functions return a non-zero value if the data was available + * in info_ptr, or return zero and do not change any of the parameters if the + * data was not available. + * + * These functions should be used instead of directly accessing png_info + * to avoid problems with future changes in the size and internal layout of + * png_info_struct. + */ +/* Returns "flag" if chunk data is valid in info_ptr. */ +PNG_EXPORT(png_uint_32,png_get_valid) PNGARG((png_structp png_ptr, +png_infop info_ptr, png_uint_32 flag)); + +/* Returns number of bytes needed to hold a transformed row. */ +PNG_EXPORT(png_size_t,png_get_rowbytes) PNGARG((png_structp png_ptr, +png_infop info_ptr)); + +#ifdef PNG_INFO_IMAGE_SUPPORTED +/* Returns row_pointers, which is an array of pointers to scanlines that was + * returned from png_read_png(). + */ +PNG_EXPORT(png_bytepp,png_get_rows) PNGARG((png_structp png_ptr, +png_infop info_ptr)); +/* Set row_pointers, which is an array of pointers to scanlines for use + * by png_write_png(). + */ +PNG_EXPORT(void,png_set_rows) PNGARG((png_structp png_ptr, + png_infop info_ptr, png_bytepp row_pointers)); +#endif + +/* Returns number of color channels in image. */ +PNG_EXPORT(png_byte,png_get_channels) PNGARG((png_structp png_ptr, +png_infop info_ptr)); + +#ifdef PNG_EASY_ACCESS_SUPPORTED +/* Returns image width in pixels. */ +PNG_EXPORT(png_uint_32, png_get_image_width) PNGARG((png_structp +png_ptr, png_infop info_ptr)); + +/* Returns image height in pixels. */ +PNG_EXPORT(png_uint_32, png_get_image_height) PNGARG((png_structp +png_ptr, png_infop info_ptr)); + +/* Returns image bit_depth. */ +PNG_EXPORT(png_byte, png_get_bit_depth) PNGARG((png_structp +png_ptr, png_infop info_ptr)); + +/* Returns image color_type. */ +PNG_EXPORT(png_byte, png_get_color_type) PNGARG((png_structp +png_ptr, png_infop info_ptr)); + +/* Returns image filter_type. */ +PNG_EXPORT(png_byte, png_get_filter_type) PNGARG((png_structp +png_ptr, png_infop info_ptr)); + +/* Returns image interlace_type. */ +PNG_EXPORT(png_byte, png_get_interlace_type) PNGARG((png_structp +png_ptr, png_infop info_ptr)); + +/* Returns image compression_type. */ +PNG_EXPORT(png_byte, png_get_compression_type) PNGARG((png_structp +png_ptr, png_infop info_ptr)); + +/* Returns image resolution in pixels per meter, from pHYs chunk data. */ +PNG_EXPORT(png_uint_32, png_get_pixels_per_meter) PNGARG((png_structp +png_ptr, png_infop info_ptr)); +PNG_EXPORT(png_uint_32, png_get_x_pixels_per_meter) PNGARG((png_structp +png_ptr, png_infop info_ptr)); +PNG_EXPORT(png_uint_32, png_get_y_pixels_per_meter) PNGARG((png_structp +png_ptr, png_infop info_ptr)); + +/* Returns pixel aspect ratio, computed from pHYs chunk data. */ +#ifdef PNG_FLOATING_POINT_SUPPORTED +PNG_EXPORT(float, png_get_pixel_aspect_ratio) PNGARG((png_structp +png_ptr, png_infop info_ptr)); +#endif + +/* Returns image x, y offset in pixels or microns, from oFFs chunk data. */ +PNG_EXPORT(png_int_32, png_get_x_offset_pixels) PNGARG((png_structp +png_ptr, png_infop info_ptr)); +PNG_EXPORT(png_int_32, png_get_y_offset_pixels) PNGARG((png_structp +png_ptr, png_infop info_ptr)); +PNG_EXPORT(png_int_32, png_get_x_offset_microns) PNGARG((png_structp +png_ptr, png_infop info_ptr)); +PNG_EXPORT(png_int_32, png_get_y_offset_microns) PNGARG((png_structp +png_ptr, png_infop info_ptr)); + +#endif /* PNG_EASY_ACCESS_SUPPORTED */ + +/* Returns pointer to signature string read from PNG header */ +PNG_EXPORT(png_bytep,png_get_signature) PNGARG((png_structp png_ptr, +png_infop info_ptr)); + +#ifdef PNG_bKGD_SUPPORTED +PNG_EXPORT(png_uint_32,png_get_bKGD) PNGARG((png_structp png_ptr, + png_infop info_ptr, png_color_16p *background)); +#endif + +#ifdef PNG_bKGD_SUPPORTED +PNG_EXPORT(void,png_set_bKGD) PNGARG((png_structp png_ptr, + png_infop info_ptr, png_color_16p background)); +#endif + +#ifdef PNG_cHRM_SUPPORTED +#ifdef PNG_FLOATING_POINT_SUPPORTED +PNG_EXPORT(png_uint_32,png_get_cHRM) PNGARG((png_structp png_ptr, + png_infop info_ptr, double *white_x, double *white_y, double *red_x, + double *red_y, double *green_x, double *green_y, double *blue_x, + double *blue_y)); +#endif +#ifdef PNG_FIXED_POINT_SUPPORTED +PNG_EXPORT(png_uint_32,png_get_cHRM_fixed) PNGARG((png_structp png_ptr, + png_infop info_ptr, png_fixed_point *int_white_x, png_fixed_point + *int_white_y, png_fixed_point *int_red_x, png_fixed_point *int_red_y, + png_fixed_point *int_green_x, png_fixed_point *int_green_y, png_fixed_point + *int_blue_x, png_fixed_point *int_blue_y)); +#endif +#endif + +#ifdef PNG_cHRM_SUPPORTED +#ifdef PNG_FLOATING_POINT_SUPPORTED +PNG_EXPORT(void,png_set_cHRM) PNGARG((png_structp png_ptr, + png_infop info_ptr, double white_x, double white_y, double red_x, + double red_y, double green_x, double green_y, double blue_x, double blue_y)); +#endif +#ifdef PNG_FIXED_POINT_SUPPORTED +PNG_EXPORT(void,png_set_cHRM_fixed) PNGARG((png_structp png_ptr, + png_infop info_ptr, png_fixed_point int_white_x, png_fixed_point int_white_y, + png_fixed_point int_red_x, png_fixed_point int_red_y, png_fixed_point + int_green_x, png_fixed_point int_green_y, png_fixed_point int_blue_x, + png_fixed_point int_blue_y)); +#endif +#endif + +#ifdef PNG_gAMA_SUPPORTED +#ifdef PNG_FLOATING_POINT_SUPPORTED +PNG_EXPORT(png_uint_32,png_get_gAMA) PNGARG((png_structp png_ptr, + png_infop info_ptr, double *file_gamma)); +#endif +PNG_EXPORT(png_uint_32,png_get_gAMA_fixed) PNGARG((png_structp png_ptr, + png_infop info_ptr, png_fixed_point *int_file_gamma)); +#endif + +#ifdef PNG_gAMA_SUPPORTED +#ifdef PNG_FLOATING_POINT_SUPPORTED +PNG_EXPORT(void,png_set_gAMA) PNGARG((png_structp png_ptr, + png_infop info_ptr, double file_gamma)); +#endif +PNG_EXPORT(void,png_set_gAMA_fixed) PNGARG((png_structp png_ptr, + png_infop info_ptr, png_fixed_point int_file_gamma)); +#endif + +#ifdef PNG_hIST_SUPPORTED +PNG_EXPORT(png_uint_32,png_get_hIST) PNGARG((png_structp png_ptr, + png_infop info_ptr, png_uint_16p *hist)); +#endif + +#ifdef PNG_hIST_SUPPORTED +PNG_EXPORT(void,png_set_hIST) PNGARG((png_structp png_ptr, + png_infop info_ptr, png_uint_16p hist)); +#endif + +PNG_EXPORT(png_uint_32,png_get_IHDR) PNGARG((png_structp png_ptr, + png_infop info_ptr, png_uint_32 *width, png_uint_32 *height, + int *bit_depth, int *color_type, int *interlace_method, + int *compression_method, int *filter_method)); + +PNG_EXPORT(void,png_set_IHDR) PNGARG((png_structp png_ptr, + png_infop info_ptr, png_uint_32 width, png_uint_32 height, int bit_depth, + int color_type, int interlace_method, int compression_method, + int filter_method)); + +#ifdef PNG_oFFs_SUPPORTED +PNG_EXPORT(png_uint_32,png_get_oFFs) PNGARG((png_structp png_ptr, + png_infop info_ptr, png_int_32 *offset_x, png_int_32 *offset_y, + int *unit_type)); +#endif + +#ifdef PNG_oFFs_SUPPORTED +PNG_EXPORT(void,png_set_oFFs) PNGARG((png_structp png_ptr, + png_infop info_ptr, png_int_32 offset_x, png_int_32 offset_y, + int unit_type)); +#endif + +#ifdef PNG_pCAL_SUPPORTED +PNG_EXPORT(png_uint_32,png_get_pCAL) PNGARG((png_structp png_ptr, + png_infop info_ptr, png_charp *purpose, png_int_32 *X0, png_int_32 *X1, + int *type, int *nparams, png_charp *units, png_charpp *params)); +#endif + +#ifdef PNG_pCAL_SUPPORTED +PNG_EXPORT(void,png_set_pCAL) PNGARG((png_structp png_ptr, + png_infop info_ptr, png_charp purpose, png_int_32 X0, png_int_32 X1, + int type, int nparams, png_charp units, png_charpp params)); +#endif + +#ifdef PNG_pHYs_SUPPORTED +PNG_EXPORT(png_uint_32,png_get_pHYs) PNGARG((png_structp png_ptr, + png_infop info_ptr, png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type)); +#endif + +#ifdef PNG_pHYs_SUPPORTED +PNG_EXPORT(void,png_set_pHYs) PNGARG((png_structp png_ptr, + png_infop info_ptr, png_uint_32 res_x, png_uint_32 res_y, int unit_type)); +#endif + +PNG_EXPORT(png_uint_32,png_get_PLTE) PNGARG((png_structp png_ptr, + png_infop info_ptr, png_colorp *palette, int *num_palette)); + +PNG_EXPORT(void,png_set_PLTE) PNGARG((png_structp png_ptr, + png_infop info_ptr, png_colorp palette, int num_palette)); + +#ifdef PNG_sBIT_SUPPORTED +PNG_EXPORT(png_uint_32,png_get_sBIT) PNGARG((png_structp png_ptr, + png_infop info_ptr, png_color_8p *sig_bit)); +#endif + +#ifdef PNG_sBIT_SUPPORTED +PNG_EXPORT(void,png_set_sBIT) PNGARG((png_structp png_ptr, + png_infop info_ptr, png_color_8p sig_bit)); +#endif + +#ifdef PNG_sRGB_SUPPORTED +PNG_EXPORT(png_uint_32,png_get_sRGB) PNGARG((png_structp png_ptr, + png_infop info_ptr, int *intent)); +#endif + +#ifdef PNG_sRGB_SUPPORTED +PNG_EXPORT(void,png_set_sRGB) PNGARG((png_structp png_ptr, + png_infop info_ptr, int intent)); +PNG_EXPORT(void,png_set_sRGB_gAMA_and_cHRM) PNGARG((png_structp png_ptr, + png_infop info_ptr, int intent)); +#endif + +#ifdef PNG_iCCP_SUPPORTED +PNG_EXPORT(png_uint_32,png_get_iCCP) PNGARG((png_structp png_ptr, + png_infop info_ptr, png_charpp name, int *compression_type, + png_charpp profile, png_uint_32 *proflen)); + /* Note to maintainer: profile should be png_bytepp */ +#endif + +#ifdef PNG_iCCP_SUPPORTED +PNG_EXPORT(void,png_set_iCCP) PNGARG((png_structp png_ptr, + png_infop info_ptr, png_charp name, int compression_type, + png_charp profile, png_uint_32 proflen)); + /* Note to maintainer: profile should be png_bytep */ +#endif + +#ifdef PNG_sPLT_SUPPORTED +PNG_EXPORT(png_uint_32,png_get_sPLT) PNGARG((png_structp png_ptr, + png_infop info_ptr, png_sPLT_tpp entries)); +#endif + +#ifdef PNG_sPLT_SUPPORTED +PNG_EXPORT(void,png_set_sPLT) PNGARG((png_structp png_ptr, + png_infop info_ptr, png_sPLT_tp entries, int nentries)); +#endif + +#ifdef PNG_TEXT_SUPPORTED +/* png_get_text also returns the number of text chunks in *num_text */ +PNG_EXPORT(png_uint_32,png_get_text) PNGARG((png_structp png_ptr, + png_infop info_ptr, png_textp *text_ptr, int *num_text)); +#endif + +/* Note while png_set_text() will accept a structure whose text, + * language, and translated keywords are NULL pointers, the structure + * returned by png_get_text will always contain regular + * zero-terminated C strings. They might be empty strings but + * they will never be NULL pointers. + */ + +#ifdef PNG_TEXT_SUPPORTED +PNG_EXPORT(void,png_set_text) PNGARG((png_structp png_ptr, + png_infop info_ptr, png_textp text_ptr, int num_text)); +#endif + +#ifdef PNG_tIME_SUPPORTED +PNG_EXPORT(png_uint_32,png_get_tIME) PNGARG((png_structp png_ptr, + png_infop info_ptr, png_timep *mod_time)); +#endif + +#ifdef PNG_tIME_SUPPORTED +PNG_EXPORT(void,png_set_tIME) PNGARG((png_structp png_ptr, + png_infop info_ptr, png_timep mod_time)); +#endif + +#ifdef PNG_tRNS_SUPPORTED +PNG_EXPORT(png_uint_32,png_get_tRNS) PNGARG((png_structp png_ptr, + png_infop info_ptr, png_bytep *trans_alpha, int *num_trans, + png_color_16p *trans_color)); +#endif + +#ifdef PNG_tRNS_SUPPORTED +PNG_EXPORT(void,png_set_tRNS) PNGARG((png_structp png_ptr, + png_infop info_ptr, png_bytep trans_alpha, int num_trans, + png_color_16p trans_color)); +#endif + +#ifdef PNG_tRNS_SUPPORTED +#endif + +#ifdef PNG_sCAL_SUPPORTED +#ifdef PNG_FLOATING_POINT_SUPPORTED +PNG_EXPORT(png_uint_32,png_get_sCAL) PNGARG((png_structp png_ptr, + png_infop info_ptr, int *unit, double *width, double *height)); +#else +#ifdef PNG_FIXED_POINT_SUPPORTED +PNG_EXPORT(png_uint_32,png_get_sCAL_s) PNGARG((png_structp png_ptr, + png_infop info_ptr, int *unit, png_charpp swidth, png_charpp sheight)); +#endif +#endif +#endif /* PNG_sCAL_SUPPORTED */ + +#ifdef PNG_sCAL_SUPPORTED +#ifdef PNG_FLOATING_POINT_SUPPORTED +PNG_EXPORT(void,png_set_sCAL) PNGARG((png_structp png_ptr, + png_infop info_ptr, int unit, double width, double height)); +#else +#ifdef PNG_FIXED_POINT_SUPPORTED +PNG_EXPORT(void,png_set_sCAL_s) PNGARG((png_structp png_ptr, + png_infop info_ptr, int unit, png_charp swidth, png_charp sheight)); +#endif +#endif +#endif /* PNG_sCAL_SUPPORTED || PNG_WRITE_sCAL_SUPPORTED */ + +#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED +/* Provide a list of chunks and how they are to be handled, if the built-in + handling or default unknown chunk handling is not desired. Any chunks not + listed will be handled in the default manner. The IHDR and IEND chunks + must not be listed. + keep = 0: follow default behaviour + = 1: do not keep + = 2: keep only if safe-to-copy + = 3: keep even if unsafe-to-copy +*/ +PNG_EXPORT(void, png_set_keep_unknown_chunks) PNGARG((png_structp + png_ptr, int keep, png_bytep chunk_list, int num_chunks)); +PNG_EXPORT(int,png_handle_as_unknown) PNGARG((png_structp png_ptr, png_bytep + chunk_name)); +#endif +#ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED +PNG_EXPORT(void, png_set_unknown_chunks) PNGARG((png_structp png_ptr, + png_infop info_ptr, png_unknown_chunkp unknowns, int num_unknowns)); +PNG_EXPORT(void, png_set_unknown_chunk_location) + PNGARG((png_structp png_ptr, png_infop info_ptr, int chunk, int location)); +PNG_EXPORT(png_uint_32,png_get_unknown_chunks) PNGARG((png_structp + png_ptr, png_infop info_ptr, png_unknown_chunkpp entries)); +#endif + +/* Png_free_data() will turn off the "valid" flag for anything it frees. + * If you need to turn it off for a chunk that your application has freed, + * you can use png_set_invalid(png_ptr, info_ptr, PNG_INFO_CHNK); + */ +PNG_EXPORT(void, png_set_invalid) PNGARG((png_structp png_ptr, + png_infop info_ptr, int mask)); + +#ifdef PNG_INFO_IMAGE_SUPPORTED +/* The "params" pointer is currently not used and is for future expansion. */ +PNG_EXPORT(void, png_read_png) PNGARG((png_structp png_ptr, + png_infop info_ptr, + int transforms, + png_voidp params)); +PNG_EXPORT(void, png_write_png) PNGARG((png_structp png_ptr, + png_infop info_ptr, + int transforms, + png_voidp params)); +#endif + +PNG_EXPORT(png_charp,png_get_copyright) PNGARG((png_structp png_ptr)); +PNG_EXPORT(png_charp,png_get_header_ver) PNGARG((png_structp png_ptr)); +PNG_EXPORT(png_charp,png_get_header_version) PNGARG((png_structp + png_ptr)); +PNG_EXPORT(png_charp,png_get_libpng_ver) PNGARG((png_structp png_ptr)); + +#ifdef PNG_MNG_FEATURES_SUPPORTED +PNG_EXPORT(png_uint_32,png_permit_mng_features) PNGARG((png_structp + png_ptr, png_uint_32 mng_features_permitted)); +#endif + +/* For use in png_set_keep_unknown, added to version 1.2.6 */ +#define PNG_HANDLE_CHUNK_AS_DEFAULT 0 +#define PNG_HANDLE_CHUNK_NEVER 1 +#define PNG_HANDLE_CHUNK_IF_SAFE 2 +#define PNG_HANDLE_CHUNK_ALWAYS 3 + +/* Strip the prepended error numbers ("#nnn ") from error and warning + * messages before passing them to the error or warning handler. + */ +#ifdef PNG_ERROR_NUMBERS_SUPPORTED +PNG_EXPORT(void,png_set_strip_error_numbers) PNGARG((png_structp + png_ptr, png_uint_32 strip_mode)); +#endif + +/* Added in libpng-1.2.6 */ +#ifdef PNG_SET_USER_LIMITS_SUPPORTED +PNG_EXPORT(void,png_set_user_limits) PNGARG((png_structp + png_ptr, png_uint_32 user_width_max, png_uint_32 user_height_max)); +PNG_EXPORT(png_uint_32,png_get_user_width_max) PNGARG((png_structp + png_ptr)); +PNG_EXPORT(png_uint_32,png_get_user_height_max) PNGARG((png_structp + png_ptr)); +/* Added in libpng-1.4.0 */ +PNG_EXPORT(void,png_set_chunk_cache_max) PNGARG((png_structp + png_ptr, png_uint_32 user_chunk_cache_max)); +PNG_EXPORT(png_uint_32,png_get_chunk_cache_max) + PNGARG((png_structp png_ptr)); +/* Added in libpng-1.4.1 */ +PNG_EXPORT(void,png_set_chunk_malloc_max) PNGARG((png_structp + png_ptr, png_alloc_size_t user_chunk_cache_max)); +PNG_EXPORT(png_alloc_size_t,png_get_chunk_malloc_max) + PNGARG((png_structp png_ptr)); +#endif + +#if defined(PNG_INCH_CONVERSIONS) && defined(PNG_FLOATING_POINT_SUPPORTED) +PNG_EXPORT(png_uint_32,png_get_pixels_per_inch) PNGARG((png_structp png_ptr, +png_infop info_ptr)); + +PNG_EXPORT(png_uint_32,png_get_x_pixels_per_inch) PNGARG((png_structp png_ptr, +png_infop info_ptr)); + +PNG_EXPORT(png_uint_32,png_get_y_pixels_per_inch) PNGARG((png_structp png_ptr, +png_infop info_ptr)); + +PNG_EXPORT(float,png_get_x_offset_inches) PNGARG((png_structp png_ptr, +png_infop info_ptr)); + +PNG_EXPORT(float,png_get_y_offset_inches) PNGARG((png_structp png_ptr, +png_infop info_ptr)); + +#ifdef PNG_pHYs_SUPPORTED +PNG_EXPORT(png_uint_32,png_get_pHYs_dpi) PNGARG((png_structp png_ptr, +png_infop info_ptr, png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type)); +#endif /* PNG_pHYs_SUPPORTED */ +#endif /* PNG_INCH_CONVERSIONS && PNG_FLOATING_POINT_SUPPORTED */ + +/* Added in libpng-1.4.0 */ +#ifdef PNG_IO_STATE_SUPPORTED +PNG_EXPORT(png_uint_32,png_get_io_state) PNGARG((png_structp png_ptr)); + +PNG_EXPORT(png_bytep,png_get_io_chunk_name) + PNGARG((png_structp png_ptr)); + +/* The flags returned by png_get_io_state() are the following: */ +#define PNG_IO_NONE 0x0000 /* no I/O at this moment */ +#define PNG_IO_READING 0x0001 /* currently reading */ +#define PNG_IO_WRITING 0x0002 /* currently writing */ +#define PNG_IO_SIGNATURE 0x0010 /* currently at the file signature */ +#define PNG_IO_CHUNK_HDR 0x0020 /* currently at the chunk header */ +#define PNG_IO_CHUNK_DATA 0x0040 /* currently at the chunk data */ +#define PNG_IO_CHUNK_CRC 0x0080 /* currently at the chunk crc */ +#define PNG_IO_MASK_OP 0x000f /* current operation: reading/writing */ +#define PNG_IO_MASK_LOC 0x00f0 /* current location: sig/hdr/data/crc */ +#endif /* ?PNG_IO_STATE_SUPPORTED */ + +/* Maintainer: Put new public prototypes here ^, in libpng.3, and project + * defs + */ + +#ifdef PNG_READ_COMPOSITE_NODIV_SUPPORTED +/* With these routines we avoid an integer divide, which will be slower on + * most machines. However, it does take more operations than the corresponding + * divide method, so it may be slower on a few RISC systems. There are two + * shifts (by 8 or 16 bits) and an addition, versus a single integer divide. + * + * Note that the rounding factors are NOT supposed to be the same! 128 and + * 32768 are correct for the NODIV code; 127 and 32767 are correct for the + * standard method. + * + * [Optimized code by Greg Roelofs and Mark Adler...blame us for bugs. :-) ] + */ + + /* fg and bg should be in `gamma 1.0' space; alpha is the opacity */ + +# define png_composite(composite, fg, alpha, bg) \ + { png_uint_16 temp = (png_uint_16)((png_uint_16)(fg) \ + * (png_uint_16)(alpha) \ + + (png_uint_16)(bg)*(png_uint_16)(255 \ + - (png_uint_16)(alpha)) + (png_uint_16)128); \ + (composite) = (png_byte)((temp + (temp >> 8)) >> 8); } + +# define png_composite_16(composite, fg, alpha, bg) \ + { png_uint_32 temp = (png_uint_32)((png_uint_32)(fg) \ + * (png_uint_32)(alpha) \ + + (png_uint_32)(bg)*(png_uint_32)(65535L \ + - (png_uint_32)(alpha)) + (png_uint_32)32768L); \ + (composite) = (png_uint_16)((temp + (temp >> 16)) >> 16); } + +#else /* Standard method using integer division */ + +# define png_composite(composite, fg, alpha, bg) \ + (composite) = (png_byte)(((png_uint_16)(fg) * (png_uint_16)(alpha) + \ + (png_uint_16)(bg) * (png_uint_16)(255 - (png_uint_16)(alpha)) + \ + (png_uint_16)127) / 255) + +# define png_composite_16(composite, fg, alpha, bg) \ + (composite) = (png_uint_16)(((png_uint_32)(fg) * (png_uint_32)(alpha) + \ + (png_uint_32)(bg)*(png_uint_32)(65535L - (png_uint_32)(alpha)) + \ + (png_uint_32)32767) / (png_uint_32)65535L) +#endif /* PNG_READ_COMPOSITE_NODIV_SUPPORTED */ + +#ifdef PNG_USE_READ_MACROS +/* Inline macros to do direct reads of bytes from the input buffer. + * The png_get_int_32() routine assumes we are using two's complement + * format for negative values, which is almost certainly true. + */ +# define png_get_uint_32(buf) \ + (((png_uint_32)(*(buf)) << 24) + \ + ((png_uint_32)(*((buf) + 1)) << 16) + \ + ((png_uint_32)(*((buf) + 2)) << 8) + \ + ((png_uint_32)(*((buf) + 3)))) +# define png_get_uint_16(buf) \ + (((png_uint_32)(*(buf)) << 8) + \ + ((png_uint_32)(*((buf) + 1)))) +# define png_get_int_32(buf) \ + ((png_int_32)((*(buf) & 0x80) \ + ? -((png_int_32)((png_get_uint_32(buf) ^ 0xffffffff)+1)) \ + : (png_int_32)png_get_uint_32(buf))) +#else +PNG_EXPORT(png_uint_32,png_get_uint_32) PNGARG((png_bytep buf)); +PNG_EXPORT(png_uint_16,png_get_uint_16) PNGARG((png_bytep buf)); +#ifdef PNG_GET_INT_32_SUPPORTED +PNG_EXPORT(png_int_32,png_get_int_32) PNGARG((png_bytep buf)); +#endif +#endif +PNG_EXPORT(png_uint_32,png_get_uint_31) + PNGARG((png_structp png_ptr, png_bytep buf)); +/* No png_get_int_16 -- may be added if there's a real need for it. */ + +/* Place a 32-bit number into a buffer in PNG byte order (big-endian). */ +PNG_EXPORT(void,png_save_uint_32) + PNGARG((png_bytep buf, png_uint_32 i)); +PNG_EXPORT(void,png_save_int_32) + PNGARG((png_bytep buf, png_int_32 i)); + +/* Place a 16-bit number into a buffer in PNG byte order. + * The parameter is declared unsigned int, not png_uint_16, + * just to avoid potential problems on pre-ANSI C compilers. + */ +PNG_EXPORT(void,png_save_uint_16) + PNGARG((png_bytep buf, unsigned int i)); +/* No png_save_int_16 -- may be added if there's a real need for it. */ + +/* ************************************************************************* */ + +/* Various modes of operation. Note that after an init, mode is set to + * zero automatically when the structure is created. + */ +#define PNG_HAVE_IHDR 0x01 +#define PNG_HAVE_PLTE 0x02 +#define PNG_HAVE_IDAT 0x04 +#define PNG_AFTER_IDAT 0x08 /* Have complete zlib datastream */ +#define PNG_HAVE_IEND 0x10 +#define PNG_HAVE_gAMA 0x20 +#define PNG_HAVE_cHRM 0x40 + +#ifdef __cplusplus +} +#endif + +#endif /* PNG_VERSION_INFO_ONLY */ +/* Do not put anything past this line */ +#endif /* PNG_H */ diff --git a/libpng/pngconf.h b/libpng/pngconf.h new file mode 100644 index 0000000..41b13e9 --- /dev/null +++ b/libpng/pngconf.h @@ -0,0 +1,1540 @@ + +/* pngconf.h - machine configurable file for libpng + * + * libpng version 1.4.4 - September 23, 2010 + * For conditions of distribution and use, see copyright notice in png.h + * Copyright (c) 1998-2010 Glenn Randers-Pehrson + * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) + * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) + * + * This code is released under the libpng license. + * For conditions of distribution and use, see the disclaimer + * and license in png.h + * + */ + +/* Any machine specific code is near the front of this file, so if you + * are configuring libpng for a machine, you may want to read the section + * starting here down to where it starts to typedef png_color, png_text, + * and png_info. + */ + +#ifndef PNGCONF_H +#define PNGCONF_H + +#ifndef PNG_NO_LIMITS_H +# include +#endif + +/* Added at libpng-1.2.9 */ + +/* config.h is created by and PNG_CONFIGURE_LIBPNG is set by the "configure" + * script. + */ +#ifdef PNG_CONFIGURE_LIBPNG +# ifdef HAVE_CONFIG_H +# include "config.h" +# endif +#endif + +/* + * Added at libpng-1.2.8 + * + * PNG_USER_CONFIG has to be defined on the compiler command line. This + * includes the resource compiler for Windows DLL configurations. + */ +#ifdef PNG_USER_CONFIG +# include "pngusr.h" +# ifndef PNG_USER_PRIVATEBUILD +# define PNG_USER_PRIVATEBUILD +# endif +#endif + +/* + * If you create a private DLL you should define in "pngusr.h" the following: + * #define PNG_USER_PRIVATEBUILD + * e.g. #define PNG_USER_PRIVATEBUILD "Build by MyCompany for xyz reasons." + * #define PNG_USER_DLLFNAME_POSTFIX + * e.g. // private DLL "libpng14gx.dll" + * #define PNG_USER_DLLFNAME_POSTFIX "gx" + * + * The following macros are also at your disposal if you want to complete the + * DLL VERSIONINFO structure. + * - PNG_USER_VERSIONINFO_COMMENTS + * - PNG_USER_VERSIONINFO_COMPANYNAME + * - PNG_USER_VERSIONINFO_LEGALTRADEMARKS + */ + +#ifdef __STDC__ +# ifdef SPECIALBUILD +# pragma message("PNG_LIBPNG_SPECIALBUILD (and deprecated SPECIALBUILD)\ + are now LIBPNG reserved macros. Use PNG_USER_PRIVATEBUILD instead.") +# endif + +# ifdef PRIVATEBUILD +# pragma message("PRIVATEBUILD is deprecated.\ + Use PNG_USER_PRIVATEBUILD instead.") +# define PNG_USER_PRIVATEBUILD PRIVATEBUILD +# endif +#endif /* __STDC__ */ + +/* End of material added to libpng-1.2.8 */ + +#ifndef PNG_VERSION_INFO_ONLY + +/* This is the size of the compression buffer, and thus the size of + * an IDAT chunk. Make this whatever size you feel is best for your + * machine. One of these will be allocated per png_struct. When this + * is full, it writes the data to the disk, and does some other + * calculations. Making this an extremely small size will slow + * the library down, but you may want to experiment to determine + * where it becomes significant, if you are concerned with memory + * usage. Note that zlib allocates at least 32Kb also. For readers, + * this describes the size of the buffer available to read the data in. + * Unless this gets smaller than the size of a row (compressed), + * it should not make much difference how big this is. + */ + +#ifndef PNG_ZBUF_SIZE +# define PNG_ZBUF_SIZE 8192 +#endif + +/* Enable if you want a write-only libpng */ + +#ifndef PNG_NO_READ_SUPPORTED +# define PNG_READ_SUPPORTED +#endif + +/* Enable if you want a read-only libpng */ + +#ifndef PNG_NO_WRITE_SUPPORTED +# define PNG_WRITE_SUPPORTED +#endif + +/* Enabled in 1.4.0. */ +#ifdef PNG_ALLOW_BENIGN_ERRORS +# define png_benign_error png_warning +# define png_chunk_benign_error png_chunk_warning +#else +# ifndef PNG_BENIGN_ERRORS_SUPPORTED +# define png_benign_error png_error +# define png_chunk_benign_error png_chunk_error +# endif +#endif + +/* Added at libpng version 1.4.0 */ +#if !defined(PNG_NO_WARNINGS) && !defined(PNG_WARNINGS_SUPPORTED) +# define PNG_WARNINGS_SUPPORTED +#endif + +/* Added at libpng version 1.4.0 */ +#if !defined(PNG_NO_ERROR_TEXT) && !defined(PNG_ERROR_TEXT_SUPPORTED) +# define PNG_ERROR_TEXT_SUPPORTED +#endif + +/* Added at libpng version 1.4.0 */ +#if !defined(PNG_NO_CHECK_cHRM) && !defined(PNG_CHECK_cHRM_SUPPORTED) +# define PNG_CHECK_cHRM_SUPPORTED +#endif + +/* Added at libpng version 1.4.0 */ +#if !defined(PNG_NO_ALIGNED_MEMORY) && !defined(PNG_ALIGNED_MEMORY_SUPPORTED) +# define PNG_ALIGNED_MEMORY_SUPPORTED +#endif + +/* Enabled by default in 1.2.0. You can disable this if you don't need to + support PNGs that are embedded in MNG datastreams */ +#ifndef PNG_NO_MNG_FEATURES +# ifndef PNG_MNG_FEATURES_SUPPORTED +# define PNG_MNG_FEATURES_SUPPORTED +# endif +#endif + +/* Added at libpng version 1.4.0 */ +#ifndef PNG_NO_FLOATING_POINT_SUPPORTED +# ifndef PNG_FLOATING_POINT_SUPPORTED +# define PNG_FLOATING_POINT_SUPPORTED +# endif +#endif + +/* Added at libpng-1.4.0beta49 for testing (this test is no longer used + in libpng and png_calloc() is always present) + */ +#define PNG_CALLOC_SUPPORTED + +/* If you are running on a machine where you cannot allocate more + * than 64K of memory at once, uncomment this. While libpng will not + * normally need that much memory in a chunk (unless you load up a very + * large file), zlib needs to know how big of a chunk it can use, and + * libpng thus makes sure to check any memory allocation to verify it + * will fit into memory. +#define PNG_MAX_MALLOC_64K + */ +#if defined(MAXSEG_64K) && !defined(PNG_MAX_MALLOC_64K) +# define PNG_MAX_MALLOC_64K +#endif + +/* Special munging to support doing things the 'cygwin' way: + * 'Normal' png-on-win32 defines/defaults: + * PNG_BUILD_DLL -- building dll + * PNG_USE_DLL -- building an application, linking to dll + * (no define) -- building static library, or building an + * application and linking to the static lib + * 'Cygwin' defines/defaults: + * PNG_BUILD_DLL -- (ignored) building the dll + * (no define) -- (ignored) building an application, linking to the dll + * PNG_STATIC -- (ignored) building the static lib, or building an + * application that links to the static lib. + * ALL_STATIC -- (ignored) building various static libs, or building an + * application that links to the static libs. + * Thus, + * a cygwin user should define either PNG_BUILD_DLL or PNG_STATIC, and + * this bit of #ifdefs will define the 'correct' config variables based on + * that. If a cygwin user *wants* to define 'PNG_USE_DLL' that's okay, but + * unnecessary. + * + * Also, the precedence order is: + * ALL_STATIC (since we can't #undef something outside our namespace) + * PNG_BUILD_DLL + * PNG_STATIC + * (nothing) == PNG_USE_DLL + * + * CYGWIN (2002-01-20): The preceding is now obsolete. With the advent + * of auto-import in binutils, we no longer need to worry about + * __declspec(dllexport) / __declspec(dllimport) and friends. Therefore, + * we don't need to worry about PNG_STATIC or ALL_STATIC when it comes + * to __declspec() stuff. However, we DO need to worry about + * PNG_BUILD_DLL and PNG_STATIC because those change some defaults + * such as CONSOLE_IO. + */ +#ifdef __CYGWIN__ +# ifdef ALL_STATIC +# ifdef PNG_BUILD_DLL +# undef PNG_BUILD_DLL +# endif +# ifdef PNG_USE_DLL +# undef PNG_USE_DLL +# endif +# ifdef PNG_DLL +# undef PNG_DLL +# endif +# ifndef PNG_STATIC +# define PNG_STATIC +# endif +# else +# ifdef PNG_BUILD_DLL +# ifdef PNG_STATIC +# undef PNG_STATIC +# endif +# ifdef PNG_USE_DLL +# undef PNG_USE_DLL +# endif +# ifndef PNG_DLL +# define PNG_DLL +# endif +# else +# ifdef PNG_STATIC +# ifdef PNG_USE_DLL +# undef PNG_USE_DLL +# endif +# ifdef PNG_DLL +# undef PNG_DLL +# endif +# else +# ifndef PNG_USE_DLL +# define PNG_USE_DLL +# endif +# ifndef PNG_DLL +# define PNG_DLL +# endif +# endif +# endif +# endif +#endif + +/* This protects us against compilers that run on a windowing system + * and thus don't have or would rather us not use the stdio types: + * stdin, stdout, and stderr. The only one currently used is stderr + * in png_error() and png_warning(). #defining PNG_NO_CONSOLE_IO will + * prevent these from being compiled and used. #defining PNG_NO_STDIO + * will also prevent these, plus will prevent the entire set of stdio + * macros and functions (FILE *, printf, etc.) from being compiled and used, + * unless (PNG_DEBUG > 0) has been #defined. + * + * #define PNG_NO_CONSOLE_IO + * #define PNG_NO_STDIO + */ + +#ifdef _WIN32_WCE +# define PNG_NO_CONSOLE_IO +# define PNG_NO_STDIO +# define PNG_NO_TIME_RFC1123 +# ifdef PNG_DEBUG +# undef PNG_DEBUG +# endif +#endif + +#if !defined(PNG_NO_STDIO) && !defined(PNG_STDIO_SUPPORTED) +# define PNG_STDIO_SUPPORTED +#endif + +#ifdef PNG_BUILD_DLL +# if !defined(PNG_CONSOLE_IO_SUPPORTED) && !defined(PNG_NO_CONSOLE_IO) +# define PNG_NO_CONSOLE_IO +# endif +#endif + +# ifdef PNG_NO_STDIO +# ifndef PNG_NO_CONSOLE_IO +# define PNG_NO_CONSOLE_IO +# endif +# ifdef PNG_DEBUG +# if (PNG_DEBUG > 0) +# include +# endif +# endif +# else +# include +# endif + +#if !(defined PNG_NO_CONSOLE_IO) && !defined(PNG_CONSOLE_IO_SUPPORTED) +# define PNG_CONSOLE_IO_SUPPORTED +#endif + +/* This macro protects us against machines that don't have function + * prototypes (ie K&R style headers). If your compiler does not handle + * function prototypes, define this macro and use the included ansi2knr. + * I've always been able to use _NO_PROTO as the indicator, but you may + * need to drag the empty declaration out in front of here, or change the + * ifdef to suit your own needs. + */ +#ifndef PNGARG + +#ifdef OF /* zlib prototype munger */ +# define PNGARG(arglist) OF(arglist) +#else + +#ifdef _NO_PROTO +# define PNGARG(arglist) () +#else +# define PNGARG(arglist) arglist +#endif /* _NO_PROTO */ + +#endif /* OF */ + +#endif /* PNGARG */ + +/* Try to determine if we are compiling on a Mac. Note that testing for + * just __MWERKS__ is not good enough, because the Codewarrior is now used + * on non-Mac platforms. + */ +#ifndef MACOS +# if (defined(__MWERKS__) && defined(macintosh)) || defined(applec) || \ + defined(THINK_C) || defined(__SC__) || defined(TARGET_OS_MAC) +# define MACOS +# endif +#endif + +/* Enough people need this for various reasons to include it here */ +#if !defined(MACOS) && !defined(RISCOS) +# include +#endif + +/* PNG_SETJMP_NOT_SUPPORTED and PNG_NO_SETJMP_SUPPORTED are deprecated. */ +#if !defined(PNG_NO_SETJMP) && \ + !defined(PNG_SETJMP_NOT_SUPPORTED) && !defined(PNG_NO_SETJMP_SUPPORTED) +# define PNG_SETJMP_SUPPORTED +#endif + +#ifdef PNG_SETJMP_SUPPORTED +/* This is an attempt to force a single setjmp behaviour on Linux. If + * the X config stuff didn't define _BSD_SOURCE we wouldn't need this. + * + * You can bypass this test if you know that your application uses exactly + * the same setjmp.h that was included when libpng was built. Only define + * PNG_SKIP_SETJMP_CHECK while building your application, prior to the + * application's '#include "png.h"'. Don't define PNG_SKIP_SETJMP_CHECK + * while building a separate libpng library for general use. + */ + +# ifndef PNG_SKIP_SETJMP_CHECK +# ifdef __linux__ +# ifdef _BSD_SOURCE +# define PNG_SAVE_BSD_SOURCE +# undef _BSD_SOURCE +# endif +# ifdef _SETJMP_H + /* If you encounter a compiler error here, see the explanation + * near the end of INSTALL. + */ + __pngconf.h__ in libpng already includes setjmp.h; + __dont__ include it again.; +# endif +# endif /* __linux__ */ +# endif /* PNG_SKIP_SETJMP_CHECK */ + + /* Include setjmp.h for error handling */ +# include + +# ifdef __linux__ +# ifdef PNG_SAVE_BSD_SOURCE +# ifdef _BSD_SOURCE +# undef _BSD_SOURCE +# endif +# define _BSD_SOURCE +# undef PNG_SAVE_BSD_SOURCE +# endif +# endif /* __linux__ */ +#endif /* PNG_SETJMP_SUPPORTED */ + +#ifdef BSD +# include +#else +# include +#endif + +/* Other defines for things like memory and the like can go here. */ + +/* This controls how fine the quantizing gets. As this allocates + * a largish chunk of memory (32K), those who are not as concerned + * with quantizing quality can decrease some or all of these. + */ + +/* Prior to libpng-1.4.2, these were PNG_DITHER_*_BITS + * These migration aids will be removed from libpng-1.5.0. + */ +#ifdef PNG_DITHER_RED_BITS +# define PNG_QUANTIZE_RED_BITS PNG_DITHER_RED_BITS +#endif +#ifdef PNG_DITHER_GREEN_BITS +# define PNG_QUANTIZE_GREEN_BITS PNG_DITHER_GREEN_BITS +#endif +#ifdef PNG_DITHER_BLUE_BITS +# define PNG_QUANTIZE_BLUE_BITS PNG_DITHER_BLUE_BITS +#endif + +#ifndef PNG_QUANTIZE_RED_BITS +# define PNG_QUANTIZE_RED_BITS 5 +#endif +#ifndef PNG_QUANTIZE_GREEN_BITS +# define PNG_QUANTIZE_GREEN_BITS 5 +#endif +#ifndef PNG_QUANTIZE_BLUE_BITS +# define PNG_QUANTIZE_BLUE_BITS 5 +#endif + +/* This controls how fine the gamma correction becomes when you + * are only interested in 8 bits anyway. Increasing this value + * results in more memory being used, and more pow() functions + * being called to fill in the gamma tables. Don't set this value + * less then 8, and even that may not work (I haven't tested it). + */ + +#ifndef PNG_MAX_GAMMA_8 +# define PNG_MAX_GAMMA_8 11 +#endif + +/* This controls how much a difference in gamma we can tolerate before + * we actually start doing gamma conversion. + */ +#ifndef PNG_GAMMA_THRESHOLD +# define PNG_GAMMA_THRESHOLD 0.05 +#endif + +/* The following uses const char * instead of char * for error + * and warning message functions, so some compilers won't complain. + * If you do not want to use const, define PNG_NO_CONST. + */ + +#ifndef PNG_CONST +# ifndef PNG_NO_CONST +# define PNG_CONST const +# else +# define PNG_CONST +# endif +#endif + +/* The following defines give you the ability to remove code from the + * library that you will not be using. I wish I could figure out how to + * automate this, but I can't do that without making it seriously hard + * on the users. So if you are not using an ability, change the #define + * to an #undef, or pass in PNG_NO_feature and that part of the library + * will not be compiled. + + * If your linker can't find a function, you may want to make sure the + * ability is defined here. Some of these depend upon some others being + * defined. I haven't figured out all the interactions here, so you may + * have to experiment awhile to get everything to compile. If you are + * creating or using a shared library, you probably shouldn't touch this, + * as it will affect the size of the structures, and this will cause bad + * things to happen if the library and/or application ever change. + */ + +/* Any features you will not be using can be undef'ed here */ + +/* GR-P, 0.96a: Set "*TRANSFORMS_SUPPORTED as default but allow user + * to turn it off with PNG_NO_READ|WRITE_TRANSFORMS on the compile line, + * then pick and choose which ones to define without having to edit this + * file. It is safe to use the PNG_NO_READ|WRITE_TRANSFORMS + * if you only want to have a png-compliant reader/writer but don't need + * any of the extra transformations. This saves about 80 kbytes in a + * typical installation of the library. (PNG_NO_* form added in version + * 1.0.1c, for consistency; PNG_*_TRANSFORMS_NOT_SUPPORTED deprecated in + * 1.4.0) + */ + +/* Ignore attempt to turn off both floating and fixed point support */ +#if !defined(PNG_FLOATING_POINT_SUPPORTED) || \ + !defined(PNG_NO_FIXED_POINT_SUPPORTED) +# define PNG_FIXED_POINT_SUPPORTED +#endif + +#ifdef PNG_READ_SUPPORTED + +/* PNG_READ_TRANSFORMS_NOT_SUPPORTED is deprecated. */ +#if !defined(PNG_READ_TRANSFORMS_NOT_SUPPORTED) && \ + !defined(PNG_NO_READ_TRANSFORMS) +# define PNG_READ_TRANSFORMS_SUPPORTED +#endif + +#ifdef PNG_READ_TRANSFORMS_SUPPORTED +# ifndef PNG_NO_READ_EXPAND +# define PNG_READ_EXPAND_SUPPORTED +# endif +# ifndef PNG_NO_READ_SHIFT +# define PNG_READ_SHIFT_SUPPORTED +# endif +# ifndef PNG_NO_READ_PACK +# define PNG_READ_PACK_SUPPORTED +# endif +# ifndef PNG_NO_READ_BGR +# define PNG_READ_BGR_SUPPORTED +# endif +# ifndef PNG_NO_READ_SWAP +# define PNG_READ_SWAP_SUPPORTED +# endif +# ifndef PNG_NO_READ_PACKSWAP +# define PNG_READ_PACKSWAP_SUPPORTED +# endif +# ifndef PNG_NO_READ_INVERT +# define PNG_READ_INVERT_SUPPORTED +# endif +# ifndef PNG_NO_READ_QUANTIZE + /* Prior to libpng-1.4.0 this was PNG_READ_DITHER_SUPPORTED */ +# ifndef PNG_NO_READ_DITHER /* This migration aid will be removed */ +# define PNG_READ_QUANTIZE_SUPPORTED +# endif +# endif +# ifndef PNG_NO_READ_BACKGROUND +# define PNG_READ_BACKGROUND_SUPPORTED +# endif +# ifndef PNG_NO_READ_16_TO_8 +# define PNG_READ_16_TO_8_SUPPORTED +# endif +# ifndef PNG_NO_READ_FILLER +# define PNG_READ_FILLER_SUPPORTED +# endif +# ifndef PNG_NO_READ_GAMMA +# define PNG_READ_GAMMA_SUPPORTED +# endif +# ifndef PNG_NO_READ_GRAY_TO_RGB +# define PNG_READ_GRAY_TO_RGB_SUPPORTED +# endif +# ifndef PNG_NO_READ_SWAP_ALPHA +# define PNG_READ_SWAP_ALPHA_SUPPORTED +# endif +# ifndef PNG_NO_READ_INVERT_ALPHA +# define PNG_READ_INVERT_ALPHA_SUPPORTED +# endif +# ifndef PNG_NO_READ_STRIP_ALPHA +# define PNG_READ_STRIP_ALPHA_SUPPORTED +# endif +# ifndef PNG_NO_READ_USER_TRANSFORM +# define PNG_READ_USER_TRANSFORM_SUPPORTED +# endif +# ifndef PNG_NO_READ_RGB_TO_GRAY +# define PNG_READ_RGB_TO_GRAY_SUPPORTED +# endif +#endif /* PNG_READ_TRANSFORMS_SUPPORTED */ + +/* PNG_PROGRESSIVE_READ_NOT_SUPPORTED is deprecated. */ +#if !defined(PNG_NO_PROGRESSIVE_READ) && \ + !defined(PNG_PROGRESSIVE_READ_NOT_SUPPORTED) /* if you don't do progressive */ +# define PNG_PROGRESSIVE_READ_SUPPORTED /* reading. This is not talking */ +#endif /* about interlacing capability! You'll */ + /* still have interlacing unless you change the following define: */ + +#define PNG_READ_INTERLACING_SUPPORTED /* required for PNG-compliant decoders */ + +/* PNG_NO_SEQUENTIAL_READ_SUPPORTED is deprecated. */ +#if !defined(PNG_NO_SEQUENTIAL_READ) && \ + !defined(PNG_SEQUENTIAL_READ_SUPPORTED) && \ + !defined(PNG_NO_SEQUENTIAL_READ_SUPPORTED) +# define PNG_SEQUENTIAL_READ_SUPPORTED +#endif + +#ifndef PNG_NO_READ_COMPOSITE_NODIV +# ifndef PNG_NO_READ_COMPOSITED_NODIV /* libpng-1.0.x misspelling */ +# define PNG_READ_COMPOSITE_NODIV_SUPPORTED /* well tested on Intel, SGI */ +# endif +#endif + +#if !defined(PNG_NO_GET_INT_32) || defined(PNG_READ_oFFS_SUPPORTED) || \ + defined(PNG_READ_pCAL_SUPPORTED) +# ifndef PNG_GET_INT_32_SUPPORTED +# define PNG_GET_INT_32_SUPPORTED +# endif +#endif + +#endif /* PNG_READ_SUPPORTED */ + +#ifdef PNG_WRITE_SUPPORTED + +/* PNG_WRITE_TRANSFORMS_NOT_SUPPORTED is deprecated. */ +#if !defined(PNG_WRITE_TRANSFORMS_NOT_SUPPORTED) && \ + !defined(PNG_NO_WRITE_TRANSFORMS) +# define PNG_WRITE_TRANSFORMS_SUPPORTED +#endif + +#ifdef PNG_WRITE_TRANSFORMS_SUPPORTED +# ifndef PNG_NO_WRITE_SHIFT +# define PNG_WRITE_SHIFT_SUPPORTED +# endif +# ifndef PNG_NO_WRITE_PACK +# define PNG_WRITE_PACK_SUPPORTED +# endif +# ifndef PNG_NO_WRITE_BGR +# define PNG_WRITE_BGR_SUPPORTED +# endif +# ifndef PNG_NO_WRITE_SWAP +# define PNG_WRITE_SWAP_SUPPORTED +# endif +# ifndef PNG_NO_WRITE_PACKSWAP +# define PNG_WRITE_PACKSWAP_SUPPORTED +# endif +# ifndef PNG_NO_WRITE_INVERT +# define PNG_WRITE_INVERT_SUPPORTED +# endif +# ifndef PNG_NO_WRITE_FILLER +# define PNG_WRITE_FILLER_SUPPORTED /* same as WRITE_STRIP_ALPHA */ +# endif +# ifndef PNG_NO_WRITE_SWAP_ALPHA +# define PNG_WRITE_SWAP_ALPHA_SUPPORTED +# endif +# ifndef PNG_NO_WRITE_INVERT_ALPHA +# define PNG_WRITE_INVERT_ALPHA_SUPPORTED +# endif +# ifndef PNG_NO_WRITE_USER_TRANSFORM +# define PNG_WRITE_USER_TRANSFORM_SUPPORTED +# endif +#endif /* PNG_WRITE_TRANSFORMS_SUPPORTED */ + +#if !defined(PNG_NO_WRITE_INTERLACING_SUPPORTED) && \ + !defined(PNG_WRITE_INTERLACING_SUPPORTED) + /* This is not required for PNG-compliant encoders, but can cause + * trouble if left undefined + */ +# define PNG_WRITE_INTERLACING_SUPPORTED +#endif + +#if !defined(PNG_NO_WRITE_WEIGHTED_FILTER) && \ + !defined(PNG_WRITE_WEIGHTED_FILTER) && \ + defined(PNG_FLOATING_POINT_SUPPORTED) +# define PNG_WRITE_WEIGHTED_FILTER_SUPPORTED +#endif + +#ifndef PNG_NO_WRITE_FLUSH +# define PNG_WRITE_FLUSH_SUPPORTED +#endif + +#if !defined(PNG_NO_SAVE_INT_32) || defined(PNG_WRITE_oFFS_SUPPORTED) || \ + defined(PNG_WRITE_pCAL_SUPPORTED) +# ifndef PNG_SAVE_INT_32_SUPPORTED +# define PNG_SAVE_INT_32_SUPPORTED +# endif +#endif + +#endif /* PNG_WRITE_SUPPORTED */ + +#define PNG_NO_ERROR_NUMBERS + +#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \ + defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) +# ifndef PNG_NO_USER_TRANSFORM_PTR +# define PNG_USER_TRANSFORM_PTR_SUPPORTED +# endif +#endif + +#if defined(PNG_STDIO_SUPPORTED) && !defined(PNG_TIME_RFC1123_SUPPORTED) +# define PNG_TIME_RFC1123_SUPPORTED +#endif + +/* This adds extra functions in pngget.c for accessing data from the + * info pointer (added in version 0.99) + * png_get_image_width() + * png_get_image_height() + * png_get_bit_depth() + * png_get_color_type() + * png_get_compression_type() + * png_get_filter_type() + * png_get_interlace_type() + * png_get_pixel_aspect_ratio() + * png_get_pixels_per_meter() + * png_get_x_offset_pixels() + * png_get_y_offset_pixels() + * png_get_x_offset_microns() + * png_get_y_offset_microns() + */ +#if !defined(PNG_NO_EASY_ACCESS) && !defined(PNG_EASY_ACCESS_SUPPORTED) +# define PNG_EASY_ACCESS_SUPPORTED +#endif + +/* Added at libpng-1.2.0 */ +#if !defined(PNG_NO_USER_MEM) && !defined(PNG_USER_MEM_SUPPORTED) +# define PNG_USER_MEM_SUPPORTED +#endif + +/* Added at libpng-1.2.6 */ +#ifndef PNG_NO_SET_USER_LIMITS +# ifndef PNG_SET_USER_LIMITS_SUPPORTED +# define PNG_SET_USER_LIMITS_SUPPORTED +# endif + /* Feature added at libpng-1.4.0, this flag added at 1.4.1 */ +# ifndef PNG_SET_CHUNK_CACHE_LIMIT_SUPPORTED +# define PNG_SET_CHUNK_CACHE_LIMIT_SUPPORTED +# endif + /* Feature added at libpng-1.4.1, this flag added at 1.4.1 */ +# ifndef PNG_SET_CHUNK_MALLOC_LIMIT_SUPPORTED +# define PNG_SET_CHUNK_MALLOC_LIMIT_SUPPORTED +# endif +#endif + +/* Added at libpng-1.2.43 */ +#ifndef PNG_USER_LIMITS_SUPPORTED +# ifndef PNG_NO_USER_LIMITS +# define PNG_USER_LIMITS_SUPPORTED +# endif +#endif + +/* Added at libpng-1.0.16 and 1.2.6. To accept all valid PNGs no matter + * how large, set these two limits to 0x7fffffffL + */ +#ifndef PNG_USER_WIDTH_MAX +# define PNG_USER_WIDTH_MAX 1000000L +#endif +#ifndef PNG_USER_HEIGHT_MAX +# define PNG_USER_HEIGHT_MAX 1000000L +#endif + +/* Added at libpng-1.2.43. To accept all valid PNGs no matter + * how large, set these two limits to 0. + */ +#ifndef PNG_USER_CHUNK_CACHE_MAX +# define PNG_USER_CHUNK_CACHE_MAX 0 +#endif + +/* Added at libpng-1.2.43 */ +#ifndef PNG_USER_CHUNK_MALLOC_MAX +# define PNG_USER_CHUNK_MALLOC_MAX 0 +#endif + +/* Added at libpng-1.4.0 */ +#if !defined(PNG_NO_IO_STATE) && !defined(PNG_IO_STATE_SUPPORTED) +# define PNG_IO_STATE_SUPPORTED +#endif + +#ifndef PNG_LITERAL_SHARP +# define PNG_LITERAL_SHARP 0x23 +#endif +#ifndef PNG_LITERAL_LEFT_SQUARE_BRACKET +# define PNG_LITERAL_LEFT_SQUARE_BRACKET 0x5b +#endif +#ifndef PNG_LITERAL_RIGHT_SQUARE_BRACKET +# define PNG_LITERAL_RIGHT_SQUARE_BRACKET 0x5d +#endif +#ifndef PNG_STRING_NEWLINE +#define PNG_STRING_NEWLINE "\n" +#endif + +/* These are currently experimental features, define them if you want */ + +/* Very little testing */ +/* +#ifdef PNG_READ_SUPPORTED +# ifndef PNG_READ_16_TO_8_ACCURATE_SCALE_SUPPORTED +# define PNG_READ_16_TO_8_ACCURATE_SCALE_SUPPORTED +# endif +#endif +*/ + +/* This is only for PowerPC big-endian and 680x0 systems */ +/* some testing */ +/* +#ifndef PNG_READ_BIG_ENDIAN_SUPPORTED +# define PNG_READ_BIG_ENDIAN_SUPPORTED +#endif +*/ + +#if !defined(PNG_NO_USE_READ_MACROS) && !defined(PNG_USE_READ_MACROS) +# define PNG_USE_READ_MACROS +#endif + +/* Buggy compilers (e.g., gcc 2.7.2.2) need PNG_NO_POINTER_INDEXING */ + +#if !defined(PNG_NO_POINTER_INDEXING) && \ + !defined(PNG_POINTER_INDEXING_SUPPORTED) +# define PNG_POINTER_INDEXING_SUPPORTED +#endif + + +/* Any chunks you are not interested in, you can undef here. The + * ones that allocate memory may be expecially important (hIST, + * tEXt, zTXt, tRNS, pCAL). Others will just save time and make png_info + * a bit smaller. + */ + +/* The size of the png_text structure changed in libpng-1.0.6 when + * iTXt support was added. iTXt support was turned off by default through + * libpng-1.2.x, to support old apps that malloc the png_text structure + * instead of calling png_set_text() and letting libpng malloc it. It + * was turned on by default in libpng-1.4.0. + */ + +/* PNG_READ_ANCILLARY_CHUNKS_NOT_SUPPORTED is deprecated. */ +#if defined(PNG_READ_SUPPORTED) && \ + !defined(PNG_READ_ANCILLARY_CHUNKS_NOT_SUPPORTED) && \ + !defined(PNG_NO_READ_ANCILLARY_CHUNKS) +# define PNG_READ_ANCILLARY_CHUNKS_SUPPORTED +#endif + +/* PNG_WRITE_ANCILLARY_CHUNKS_NOT_SUPPORTED is deprecated. */ +#if defined(PNG_WRITE_SUPPORTED) && \ + !defined(PNG_WRITE_ANCILLARY_CHUNKS_NOT_SUPPORTED) && \ + !defined(PNG_NO_WRITE_ANCILLARY_CHUNKS) +# define PNG_WRITE_ANCILLARY_CHUNKS_SUPPORTED +#endif + +#ifdef PNG_READ_ANCILLARY_CHUNKS_SUPPORTED + +#ifdef PNG_NO_READ_TEXT +# define PNG_NO_READ_iTXt +# define PNG_NO_READ_tEXt +# define PNG_NO_READ_zTXt +#endif + +#ifndef PNG_NO_READ_bKGD +# define PNG_READ_bKGD_SUPPORTED +# define PNG_bKGD_SUPPORTED +#endif +#ifndef PNG_NO_READ_cHRM +# define PNG_READ_cHRM_SUPPORTED +# define PNG_cHRM_SUPPORTED +#endif +#ifndef PNG_NO_READ_gAMA +# define PNG_READ_gAMA_SUPPORTED +# define PNG_gAMA_SUPPORTED +#endif +#ifndef PNG_NO_READ_hIST +# define PNG_READ_hIST_SUPPORTED +# define PNG_hIST_SUPPORTED +#endif +#ifndef PNG_NO_READ_iCCP +# define PNG_READ_iCCP_SUPPORTED +# define PNG_iCCP_SUPPORTED +#endif +#ifndef PNG_NO_READ_iTXt +# ifndef PNG_READ_iTXt_SUPPORTED +# define PNG_READ_iTXt_SUPPORTED +# endif +# ifndef PNG_iTXt_SUPPORTED +# define PNG_iTXt_SUPPORTED +# endif +#endif +#ifndef PNG_NO_READ_oFFs +# define PNG_READ_oFFs_SUPPORTED +# define PNG_oFFs_SUPPORTED +#endif +#ifndef PNG_NO_READ_pCAL +# define PNG_READ_pCAL_SUPPORTED +# define PNG_pCAL_SUPPORTED +#endif +#ifndef PNG_NO_READ_sCAL +# define PNG_READ_sCAL_SUPPORTED +# define PNG_sCAL_SUPPORTED +#endif +#ifndef PNG_NO_READ_pHYs +# define PNG_READ_pHYs_SUPPORTED +# define PNG_pHYs_SUPPORTED +#endif +#ifndef PNG_NO_READ_sBIT +# define PNG_READ_sBIT_SUPPORTED +# define PNG_sBIT_SUPPORTED +#endif +#ifndef PNG_NO_READ_sPLT +# define PNG_READ_sPLT_SUPPORTED +# define PNG_sPLT_SUPPORTED +#endif +#ifndef PNG_NO_READ_sRGB +# define PNG_READ_sRGB_SUPPORTED +# define PNG_sRGB_SUPPORTED +#endif +#ifndef PNG_NO_READ_tEXt +# define PNG_READ_tEXt_SUPPORTED +# define PNG_tEXt_SUPPORTED +#endif +#ifndef PNG_NO_READ_tIME +# define PNG_READ_tIME_SUPPORTED +# define PNG_tIME_SUPPORTED +#endif +#ifndef PNG_NO_READ_tRNS +# define PNG_READ_tRNS_SUPPORTED +# define PNG_tRNS_SUPPORTED +#endif +#ifndef PNG_NO_READ_zTXt +# define PNG_READ_zTXt_SUPPORTED +# define PNG_zTXt_SUPPORTED +#endif +#ifndef PNG_NO_READ_OPT_PLTE +# define PNG_READ_OPT_PLTE_SUPPORTED /* only affects support of the */ +#endif /* optional PLTE chunk in RGB and RGBA images */ +#if defined(PNG_READ_iTXt_SUPPORTED) || defined(PNG_READ_tEXt_SUPPORTED) || \ + defined(PNG_READ_zTXt_SUPPORTED) +# define PNG_READ_TEXT_SUPPORTED +# define PNG_TEXT_SUPPORTED +#endif + +#endif /* PNG_READ_ANCILLARY_CHUNKS_SUPPORTED */ + +#ifndef PNG_NO_READ_UNKNOWN_CHUNKS +# ifndef PNG_READ_UNKNOWN_CHUNKS_SUPPORTED +# define PNG_READ_UNKNOWN_CHUNKS_SUPPORTED +# endif +# ifndef PNG_UNKNOWN_CHUNKS_SUPPORTED +# define PNG_UNKNOWN_CHUNKS_SUPPORTED +# endif +# ifndef PNG_READ_USER_CHUNKS_SUPPORTED +# define PNG_READ_USER_CHUNKS_SUPPORTED +# endif +#endif +#ifndef PNG_NO_READ_USER_CHUNKS +# ifndef PNG_READ_USER_CHUNKS_SUPPORTED +# define PNG_READ_USER_CHUNKS_SUPPORTED +# endif +# ifndef PNG_USER_CHUNKS_SUPPORTED +# define PNG_USER_CHUNKS_SUPPORTED +# endif +#endif +#ifndef PNG_NO_HANDLE_AS_UNKNOWN +# ifndef PNG_HANDLE_AS_UNKNOWN_SUPPORTED +# define PNG_HANDLE_AS_UNKNOWN_SUPPORTED +# endif +#endif + +#ifdef PNG_WRITE_SUPPORTED +#ifdef PNG_WRITE_ANCILLARY_CHUNKS_SUPPORTED + +#ifdef PNG_NO_WRITE_TEXT +# define PNG_NO_WRITE_iTXt +# define PNG_NO_WRITE_tEXt +# define PNG_NO_WRITE_zTXt +#endif +#ifndef PNG_NO_WRITE_bKGD +# define PNG_WRITE_bKGD_SUPPORTED +# ifndef PNG_bKGD_SUPPORTED +# define PNG_bKGD_SUPPORTED +# endif +#endif +#ifndef PNG_NO_WRITE_cHRM +# define PNG_WRITE_cHRM_SUPPORTED +# ifndef PNG_cHRM_SUPPORTED +# define PNG_cHRM_SUPPORTED +# endif +#endif +#ifndef PNG_NO_WRITE_gAMA +# define PNG_WRITE_gAMA_SUPPORTED +# ifndef PNG_gAMA_SUPPORTED +# define PNG_gAMA_SUPPORTED +# endif +#endif +#ifndef PNG_NO_WRITE_hIST +# define PNG_WRITE_hIST_SUPPORTED +# ifndef PNG_hIST_SUPPORTED +# define PNG_hIST_SUPPORTED +# endif +#endif +#ifndef PNG_NO_WRITE_iCCP +# define PNG_WRITE_iCCP_SUPPORTED +# ifndef PNG_iCCP_SUPPORTED +# define PNG_iCCP_SUPPORTED +# endif +#endif +#ifndef PNG_NO_WRITE_iTXt +# ifndef PNG_WRITE_iTXt_SUPPORTED +# define PNG_WRITE_iTXt_SUPPORTED +# endif +# ifndef PNG_iTXt_SUPPORTED +# define PNG_iTXt_SUPPORTED +# endif +#endif +#ifndef PNG_NO_WRITE_oFFs +# define PNG_WRITE_oFFs_SUPPORTED +# ifndef PNG_oFFs_SUPPORTED +# define PNG_oFFs_SUPPORTED +# endif +#endif +#ifndef PNG_NO_WRITE_pCAL +# define PNG_WRITE_pCAL_SUPPORTED +# ifndef PNG_pCAL_SUPPORTED +# define PNG_pCAL_SUPPORTED +# endif +#endif +#ifndef PNG_NO_WRITE_sCAL +# define PNG_WRITE_sCAL_SUPPORTED +# ifndef PNG_sCAL_SUPPORTED +# define PNG_sCAL_SUPPORTED +# endif +#endif +#ifndef PNG_NO_WRITE_pHYs +# define PNG_WRITE_pHYs_SUPPORTED +# ifndef PNG_pHYs_SUPPORTED +# define PNG_pHYs_SUPPORTED +# endif +#endif +#ifndef PNG_NO_WRITE_sBIT +# define PNG_WRITE_sBIT_SUPPORTED +# ifndef PNG_sBIT_SUPPORTED +# define PNG_sBIT_SUPPORTED +# endif +#endif +#ifndef PNG_NO_WRITE_sPLT +# define PNG_WRITE_sPLT_SUPPORTED +# ifndef PNG_sPLT_SUPPORTED +# define PNG_sPLT_SUPPORTED +# endif +#endif +#ifndef PNG_NO_WRITE_sRGB +# define PNG_WRITE_sRGB_SUPPORTED +# ifndef PNG_sRGB_SUPPORTED +# define PNG_sRGB_SUPPORTED +# endif +#endif +#ifndef PNG_NO_WRITE_tEXt +# define PNG_WRITE_tEXt_SUPPORTED +# ifndef PNG_tEXt_SUPPORTED +# define PNG_tEXt_SUPPORTED +# endif +#endif +#ifndef PNG_NO_WRITE_tIME +# define PNG_WRITE_tIME_SUPPORTED +# ifndef PNG_tIME_SUPPORTED +# define PNG_tIME_SUPPORTED +# endif +#endif +#ifndef PNG_NO_WRITE_tRNS +# define PNG_WRITE_tRNS_SUPPORTED +# ifndef PNG_tRNS_SUPPORTED +# define PNG_tRNS_SUPPORTED +# endif +#endif +#ifndef PNG_NO_WRITE_zTXt +# define PNG_WRITE_zTXt_SUPPORTED +# ifndef PNG_zTXt_SUPPORTED +# define PNG_zTXt_SUPPORTED +# endif +#endif +#if defined(PNG_WRITE_iTXt_SUPPORTED) || defined(PNG_WRITE_tEXt_SUPPORTED) || \ + defined(PNG_WRITE_zTXt_SUPPORTED) +# define PNG_WRITE_TEXT_SUPPORTED +# ifndef PNG_TEXT_SUPPORTED +# define PNG_TEXT_SUPPORTED +# endif +#endif + +#ifdef PNG_WRITE_tIME_SUPPORTED +# ifndef PNG_NO_CONVERT_tIME +# ifndef _WIN32_WCE +/* The "tm" structure is not supported on WindowsCE */ +# ifndef PNG_CONVERT_tIME_SUPPORTED +# define PNG_CONVERT_tIME_SUPPORTED +# endif +# endif +# endif +#endif + +#endif /* PNG_WRITE_ANCILLARY_CHUNKS_SUPPORTED */ + +#ifndef PNG_NO_WRITE_FILTER +# ifndef PNG_WRITE_FILTER_SUPPORTED +# define PNG_WRITE_FILTER_SUPPORTED +# endif +#endif + +#ifndef PNG_NO_WRITE_UNKNOWN_CHUNKS +# define PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED +# ifndef PNG_UNKNOWN_CHUNKS_SUPPORTED +# define PNG_UNKNOWN_CHUNKS_SUPPORTED +# endif +#endif +#ifndef PNG_NO_HANDLE_AS_UNKNOWN +# ifndef PNG_HANDLE_AS_UNKNOWN_SUPPORTED +# define PNG_HANDLE_AS_UNKNOWN_SUPPORTED +# endif +#endif +#endif /* PNG_WRITE_SUPPORTED */ + +/* Turn this off to disable png_read_png() and + * png_write_png() and leave the row_pointers member + * out of the info structure. + */ +#ifndef PNG_NO_INFO_IMAGE +# define PNG_INFO_IMAGE_SUPPORTED +#endif + +/* Need the time information for converting tIME chunks */ +#ifdef PNG_CONVERT_tIME_SUPPORTED + /* "time.h" functions are not supported on WindowsCE */ +# include +#endif + +/* Some typedefs to get us started. These should be safe on most of the + * common platforms. The typedefs should be at least as large as the + * numbers suggest (a png_uint_32 must be at least 32 bits long), but they + * don't have to be exactly that size. Some compilers dislike passing + * unsigned shorts as function parameters, so you may be better off using + * unsigned int for png_uint_16. + */ + +#if defined(INT_MAX) && (INT_MAX > 0x7ffffffeL) +typedef unsigned int png_uint_32; +typedef int png_int_32; +#else +typedef unsigned long png_uint_32; +typedef long png_int_32; +#endif +typedef unsigned short png_uint_16; +typedef short png_int_16; +typedef unsigned char png_byte; + +#ifdef PNG_NO_SIZE_T + typedef unsigned int png_size_t; +#else + typedef size_t png_size_t; +#endif +#define png_sizeof(x) (sizeof (x)) + +/* The following is needed for medium model support. It cannot be in the + * pngpriv.h header. Needs modification for other compilers besides + * MSC. Model independent support declares all arrays and pointers to be + * large using the far keyword. The zlib version used must also support + * model independent data. As of version zlib 1.0.4, the necessary changes + * have been made in zlib. The USE_FAR_KEYWORD define triggers other + * changes that are needed. (Tim Wegner) + */ + +/* Separate compiler dependencies (problem here is that zlib.h always + * defines FAR. (SJT) + */ +#ifdef __BORLANDC__ +# if defined(__LARGE__) || defined(__HUGE__) || defined(__COMPACT__) +# define LDATA 1 +# else +# define LDATA 0 +# endif + /* GRR: why is Cygwin in here? Cygwin is not Borland C... */ +# if !defined(__WIN32__) && !defined(__FLAT__) && !defined(__CYGWIN__) +# define PNG_MAX_MALLOC_64K +# if (LDATA != 1) +# ifndef FAR +# define FAR __far +# endif +# define USE_FAR_KEYWORD +# endif /* LDATA != 1 */ + /* Possibly useful for moving data out of default segment. + * Uncomment it if you want. Could also define FARDATA as + * const if your compiler supports it. (SJT) +# define FARDATA FAR + */ +# endif /* __WIN32__, __FLAT__, __CYGWIN__ */ +#endif /* __BORLANDC__ */ + + +/* Suggest testing for specific compiler first before testing for + * FAR. The Watcom compiler defines both __MEDIUM__ and M_I86MM, + * making reliance oncertain keywords suspect. (SJT) + */ + +/* MSC Medium model */ +#ifdef FAR +# ifdef M_I86MM +# define USE_FAR_KEYWORD +# define FARDATA FAR +# include +# endif +#endif + +/* SJT: default case */ +#ifndef FAR +# define FAR +#endif + +/* At this point FAR is always defined */ +#ifndef FARDATA +# define FARDATA +#endif + +/* Typedef for floating-point numbers that are converted + to fixed-point with a multiple of 100,000, e.g., int_gamma */ +typedef png_int_32 png_fixed_point; + +/* Add typedefs for pointers */ +typedef void FAR * png_voidp; +typedef png_byte FAR * png_bytep; +typedef png_uint_32 FAR * png_uint_32p; +typedef png_int_32 FAR * png_int_32p; +typedef png_uint_16 FAR * png_uint_16p; +typedef png_int_16 FAR * png_int_16p; +typedef PNG_CONST char FAR * png_const_charp; +typedef char FAR * png_charp; +typedef png_fixed_point FAR * png_fixed_point_p; + +#ifndef PNG_NO_STDIO +typedef FILE * png_FILE_p; +#endif + +#ifdef PNG_FLOATING_POINT_SUPPORTED +typedef double FAR * png_doublep; +#endif + +/* Pointers to pointers; i.e. arrays */ +typedef png_byte FAR * FAR * png_bytepp; +typedef png_uint_32 FAR * FAR * png_uint_32pp; +typedef png_int_32 FAR * FAR * png_int_32pp; +typedef png_uint_16 FAR * FAR * png_uint_16pp; +typedef png_int_16 FAR * FAR * png_int_16pp; +typedef PNG_CONST char FAR * FAR * png_const_charpp; +typedef char FAR * FAR * png_charpp; +typedef png_fixed_point FAR * FAR * png_fixed_point_pp; +#ifdef PNG_FLOATING_POINT_SUPPORTED +typedef double FAR * FAR * png_doublepp; +#endif + +/* Pointers to pointers to pointers; i.e., pointer to array */ +typedef char FAR * FAR * FAR * png_charppp; + +/* Define PNG_BUILD_DLL if the module being built is a Windows + * LIBPNG DLL. + * + * Define PNG_USE_DLL if you want to *link* to the Windows LIBPNG DLL. + * It is equivalent to Microsoft predefined macro _DLL that is + * automatically defined when you compile using the share + * version of the CRT (C Run-Time library) + * + * The cygwin mods make this behavior a little different: + * Define PNG_BUILD_DLL if you are building a dll for use with cygwin + * Define PNG_STATIC if you are building a static library for use with cygwin, + * -or- if you are building an application that you want to link to the + * static library. + * PNG_USE_DLL is defined by default (no user action needed) unless one of + * the other flags is defined. + */ + +#if !defined(PNG_DLL) && (defined(PNG_BUILD_DLL) || defined(PNG_USE_DLL)) +# define PNG_DLL +#endif + +/* If you define PNGAPI, e.g., with compiler option "-DPNGAPI=__stdcall", + * you may get warnings regarding the linkage of png_zalloc and png_zfree. + * Don't ignore those warnings; you must also reset the default calling + * convention in your compiler to match your PNGAPI, and you must build + * zlib and your applications the same way you build libpng. + */ + +#ifdef __CYGWIN__ +# undef PNGAPI +# define PNGAPI __cdecl +# undef PNG_IMPEXP +# define PNG_IMPEXP +#endif + +#ifdef __WATCOMC__ +# ifndef PNGAPI +# define PNGAPI +# endif +#endif + +#if defined(__MINGW32__) && !defined(PNG_MODULEDEF) +# ifndef PNG_NO_MODULEDEF +# define PNG_NO_MODULEDEF +# endif +#endif + +#if !defined(PNG_IMPEXP) && defined(PNG_BUILD_DLL) && !defined(PNG_NO_MODULEDEF) +# define PNG_IMPEXP +#endif + +#if defined(PNG_DLL) || defined(_DLL) || defined(__DLL__ ) || \ + (( defined(_Windows) || defined(_WINDOWS) || \ + defined(WIN32) || defined(_WIN32) || defined(__WIN32__) )) + +# ifndef PNGAPI +# if defined(__GNUC__) || (defined (_MSC_VER) && (_MSC_VER >= 800)) +# define PNGAPI __cdecl +# else +# define PNGAPI _cdecl +# endif +# endif + +# if !defined(PNG_IMPEXP) && (!defined(PNG_DLL) || \ + 0 /* WINCOMPILER_WITH_NO_SUPPORT_FOR_DECLIMPEXP */) +# define PNG_IMPEXP +# endif + +# ifndef PNG_IMPEXP + +# define PNG_EXPORT_TYPE1(type,symbol) PNG_IMPEXP type PNGAPI symbol +# define PNG_EXPORT_TYPE2(type,symbol) type PNG_IMPEXP PNGAPI symbol + + /* Borland/Microsoft */ +# if defined(_MSC_VER) || defined(__BORLANDC__) +# if (_MSC_VER >= 800) || (__BORLANDC__ >= 0x500) +# define PNG_EXPORT PNG_EXPORT_TYPE1 +# else +# define PNG_EXPORT PNG_EXPORT_TYPE2 +# ifdef PNG_BUILD_DLL +# define PNG_IMPEXP __export +# else +# define PNG_IMPEXP /*__import */ /* doesn't exist AFAIK in VC++ */ +# endif /* Exists in Borland C++ for + C++ classes (== huge) */ +# endif +# endif + +# ifndef PNG_IMPEXP +# ifdef PNG_BUILD_DLL +# define PNG_IMPEXP __declspec(dllexport) +# else +# define PNG_IMPEXP __declspec(dllimport) +# endif +# endif +# endif /* PNG_IMPEXP */ +#else /* !(DLL || non-cygwin WINDOWS) */ +# if (defined(__IBMC__) || defined(__IBMCPP__)) && defined(__OS2__) +# ifndef PNGAPI +# define PNGAPI _System +# endif +# else +# if 0 /* ... other platforms, with other meanings */ +# endif +# endif +#endif + +#ifndef PNGAPI +# define PNGAPI +#endif +#ifndef PNG_IMPEXP +# define PNG_IMPEXP +#endif + +#ifdef PNG_BUILDSYMS +# ifndef PNG_EXPORT +# define PNG_EXPORT(type,symbol) PNG_FUNCTION_EXPORT symbol END +# endif +#endif + +#ifndef PNG_EXPORT +# define PNG_EXPORT(type,symbol) PNG_IMPEXP type PNGAPI symbol +#endif + +#define PNG_USE_LOCAL_ARRAYS /* Not used in libpng, defined for legacy apps */ + +/* Support for compiler specific function attributes. These are used + * so that where compiler support is available incorrect use of API + * functions in png.h will generate compiler warnings. + * + * Added at libpng-1.2.41. + */ + +#ifndef PNG_NO_PEDANTIC_WARNINGS +# ifndef PNG_PEDANTIC_WARNINGS_SUPPORTED +# define PNG_PEDANTIC_WARNINGS_SUPPORTED +# endif +#endif + +#ifdef PNG_PEDANTIC_WARNINGS_SUPPORTED +/* Support for compiler specific function attributes. These are used + * so that where compiler support is available incorrect use of API + * functions in png.h will generate compiler warnings. Added at libpng + * version 1.2.41. + */ +# ifdef __GNUC__ +# ifndef PNG_USE_RESULT +# define PNG_USE_RESULT __attribute__((__warn_unused_result__)) +# endif +# ifndef PNG_NORETURN +# define PNG_NORETURN __attribute__((__noreturn__)) +# endif +# ifndef PNG_ALLOCATED +# define PNG_ALLOCATED __attribute__((__malloc__)) +# endif + + /* This specifically protects structure members that should only be + * accessed from within the library, therefore should be empty during + * a library build. + */ +# ifndef PNG_DEPRECATED +# define PNG_DEPRECATED __attribute__((__deprecated__)) +# endif +# ifndef PNG_DEPSTRUCT +# define PNG_DEPSTRUCT __attribute__((__deprecated__)) +# endif +# ifndef PNG_PRIVATE +# if 0 /* Doesn't work so we use deprecated instead*/ +# define PNG_PRIVATE \ + __attribute__((warning("This function is not exported by libpng."))) +# else +# define PNG_PRIVATE \ + __attribute__((__deprecated__)) +# endif +# endif /* PNG_PRIVATE */ +# endif /* __GNUC__ */ +#endif /* PNG_PEDANTIC_WARNINGS */ + +#ifndef PNG_DEPRECATED +# define PNG_DEPRECATED /* Use of this function is deprecated */ +#endif +#ifndef PNG_USE_RESULT +# define PNG_USE_RESULT /* The result of this function must be checked */ +#endif +#ifndef PNG_NORETURN +# define PNG_NORETURN /* This function does not return */ +#endif +#ifndef PNG_ALLOCATED +# define PNG_ALLOCATED /* The result of the function is new memory */ +#endif +#ifndef PNG_DEPSTRUCT +# define PNG_DEPSTRUCT /* Access to this struct member is deprecated */ +#endif +#ifndef PNG_PRIVATE +# define PNG_PRIVATE /* This is a private libpng function */ +#endif + +/* Users may want to use these so they are not private. Any library + * functions that are passed far data must be model-independent. + */ + +/* memory model/platform independent fns */ +#ifndef PNG_ABORT +# if (defined(_Windows) || defined(_WINDOWS) || defined(_WINDOWS_)) +# define PNG_ABORT() ExitProcess(0) +# else +# define PNG_ABORT() abort() +# endif +#endif + +#ifdef USE_FAR_KEYWORD +/* Use this to make far-to-near assignments */ +# define CHECK 1 +# define NOCHECK 0 +# define CVT_PTR(ptr) (png_far_to_near(png_ptr,ptr,CHECK)) +# define CVT_PTR_NOCHECK(ptr) (png_far_to_near(png_ptr,ptr,NOCHECK)) +# define png_strcpy _fstrcpy +# define png_strncpy _fstrncpy /* Added to v 1.2.6 */ +# define png_strlen _fstrlen +# define png_memcmp _fmemcmp /* SJT: added */ +# define png_memcpy _fmemcpy +# define png_memset _fmemset +# define png_sprintf sprintf +#else +# if (defined(_Windows) || defined(_WINDOWS) || defined(_WINDOWS_)) +# /* Favor Windows over C runtime fns */ +# define CVT_PTR(ptr) (ptr) +# define CVT_PTR_NOCHECK(ptr) (ptr) +# define png_strcpy lstrcpyA +# define png_strncpy lstrcpynA +# define png_strlen lstrlenA +# define png_memcmp memcmp +# define png_memcpy CopyMemory +# define png_memset memset +# define png_sprintf wsprintfA +# else +# define CVT_PTR(ptr) (ptr) +# define CVT_PTR_NOCHECK(ptr) (ptr) +# define png_strcpy strcpy +# define png_strncpy strncpy /* Added to v 1.2.6 */ +# define png_strlen strlen +# define png_memcmp memcmp /* SJT: added */ +# define png_memcpy memcpy +# define png_memset memset +# define png_sprintf sprintf +# endif +#endif + +#ifndef PNG_NO_SNPRINTF +# ifdef _MSC_VER +# define png_snprintf _snprintf /* Added to v 1.2.19 */ +# define png_snprintf2 _snprintf +# define png_snprintf6 _snprintf +# else +# define png_snprintf snprintf /* Added to v 1.2.19 */ +# define png_snprintf2 snprintf +# define png_snprintf6 snprintf +# endif +#else + /* You don't have or don't want to use snprintf(). Caution: Using + * sprintf instead of snprintf exposes your application to accidental + * or malevolent buffer overflows. If you don't have snprintf() + * as a general rule you should provide one (you can get one from + * Portable OpenSSH). + */ +# define png_snprintf(s1,n,fmt,x1) png_sprintf(s1,fmt,x1) +# define png_snprintf2(s1,n,fmt,x1,x2) png_sprintf(s1,fmt,x1,x2) +# define png_snprintf6(s1,n,fmt,x1,x2,x3,x4,x5,x6) \ + png_sprintf(s1,fmt,x1,x2,x3,x4,x5,x6) +#endif + +/* png_alloc_size_t is guaranteed to be no smaller than png_size_t, + * and no smaller than png_uint_32. Casts from png_size_t or png_uint_32 + * to png_alloc_size_t are not necessary; in fact, it is recommended + * not to use them at all so that the compiler can complain when something + * turns out to be problematic. + * Casts in the other direction (from png_alloc_size_t to png_size_t or + * png_uint_32) should be explicitly applied; however, we do not expect + * to encounter practical situations that require such conversions. + */ +#if defined(__TURBOC__) && !defined(__FLAT__) + typedef unsigned long png_alloc_size_t; +#else +# if defined(_MSC_VER) && defined(MAXSEG_64K) + typedef unsigned long png_alloc_size_t; +# else + /* This is an attempt to detect an old Windows system where (int) is + * actually 16 bits, in that case png_malloc must have an argument with a + * bigger size to accomodate the requirements of the library. + */ +# if (defined(_Windows) || defined(_WINDOWS) || defined(_WINDOWS_)) && \ + (!defined(INT_MAX) || INT_MAX <= 0x7ffffffeL) + typedef DWORD png_alloc_size_t; +# else + typedef png_size_t png_alloc_size_t; +# endif +# endif +#endif +/* End of memory model/platform independent support */ + +/* Just a little check that someone hasn't tried to define something + * contradictory. + */ +#if (PNG_ZBUF_SIZE > 65536L) && defined(PNG_MAX_MALLOC_64K) +# undef PNG_ZBUF_SIZE +# define PNG_ZBUF_SIZE 65536L +#endif + + +/* Added at libpng-1.2.8 */ +#endif /* PNG_VERSION_INFO_ONLY */ + +#endif /* PNGCONF_H */ diff --git a/libpng/pngerror.c b/libpng/pngerror.c new file mode 100644 index 0000000..633eae2 --- /dev/null +++ b/libpng/pngerror.c @@ -0,0 +1,402 @@ + +/* pngerror.c - stub functions for i/o and memory allocation + * + * Last changed in libpng 1.4.0 [January 3, 2010] + * Copyright (c) 1998-2010 Glenn Randers-Pehrson + * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) + * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) + * + * This code is released under the libpng license. + * For conditions of distribution and use, see the disclaimer + * and license in png.h + * + * This file provides a location for all error handling. Users who + * need special error handling are expected to write replacement functions + * and use png_set_error_fn() to use those functions. See the instructions + * at each function. + */ + +#define PNG_NO_PEDANTIC_WARNINGS +#include "png.h" +#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED) +#include "pngpriv.h" + +static void /* PRIVATE */ +png_default_error PNGARG((png_structp png_ptr, + png_const_charp error_message)) PNG_NORETURN; +#ifdef PNG_WARNINGS_SUPPORTED +static void /* PRIVATE */ +png_default_warning PNGARG((png_structp png_ptr, + png_const_charp warning_message)); +#endif /* PNG_WARNINGS_SUPPORTED */ + +/* This function is called whenever there is a fatal error. This function + * should not be changed. If there is a need to handle errors differently, + * you should supply a replacement error function and use png_set_error_fn() + * to replace the error function at run-time. + */ +#ifdef PNG_ERROR_TEXT_SUPPORTED +void PNGAPI +png_error(png_structp png_ptr, png_const_charp error_message) +{ +#ifdef PNG_ERROR_NUMBERS_SUPPORTED + char msg[16]; + if (png_ptr != NULL) + { + if (png_ptr->flags& + (PNG_FLAG_STRIP_ERROR_NUMBERS|PNG_FLAG_STRIP_ERROR_TEXT)) + { + if (*error_message == PNG_LITERAL_SHARP) + { + /* Strip "#nnnn " from beginning of error message. */ + int offset; + for (offset = 1; offset<15; offset++) + if (error_message[offset] == ' ') + break; + if (png_ptr->flags&PNG_FLAG_STRIP_ERROR_TEXT) + { + int i; + for (i = 0; i < offset - 1; i++) + msg[i] = error_message[i + 1]; + msg[i - 1] = '\0'; + error_message = msg; + } + else + error_message += offset; + } + else + { + if (png_ptr->flags&PNG_FLAG_STRIP_ERROR_TEXT) + { + msg[0] = '0'; + msg[1] = '\0'; + error_message = msg; + } + } + } + } +#endif + if (png_ptr != NULL && png_ptr->error_fn != NULL) + (*(png_ptr->error_fn))(png_ptr, error_message); + + /* If the custom handler doesn't exist, or if it returns, + use the default handler, which will not return. */ + png_default_error(png_ptr, error_message); +} +#else +void PNGAPI +png_err(png_structp png_ptr) +{ + if (png_ptr != NULL && png_ptr->error_fn != NULL) + (*(png_ptr->error_fn))(png_ptr, '\0'); + + /* If the custom handler doesn't exist, or if it returns, + use the default handler, which will not return. */ + png_default_error(png_ptr, '\0'); +} +#endif /* PNG_ERROR_TEXT_SUPPORTED */ + +#ifdef PNG_WARNINGS_SUPPORTED +/* This function is called whenever there is a non-fatal error. This function + * should not be changed. If there is a need to handle warnings differently, + * you should supply a replacement warning function and use + * png_set_error_fn() to replace the warning function at run-time. + */ +void PNGAPI +png_warning(png_structp png_ptr, png_const_charp warning_message) +{ + int offset = 0; + if (png_ptr != NULL) + { +#ifdef PNG_ERROR_NUMBERS_SUPPORTED + if (png_ptr->flags& + (PNG_FLAG_STRIP_ERROR_NUMBERS|PNG_FLAG_STRIP_ERROR_TEXT)) +#endif + { + if (*warning_message == PNG_LITERAL_SHARP) + { + for (offset = 1; offset < 15; offset++) + if (warning_message[offset] == ' ') + break; + } + } + } + if (png_ptr != NULL && png_ptr->warning_fn != NULL) + (*(png_ptr->warning_fn))(png_ptr, warning_message + offset); + else + png_default_warning(png_ptr, warning_message + offset); +} +#endif /* PNG_WARNINGS_SUPPORTED */ + +#ifdef PNG_BENIGN_ERRORS_SUPPORTED +void PNGAPI +png_benign_error(png_structp png_ptr, png_const_charp error_message) +{ + if (png_ptr->flags & PNG_FLAG_BENIGN_ERRORS_WARN) + png_warning(png_ptr, error_message); + else + png_error(png_ptr, error_message); +} +#endif + +/* These utilities are used internally to build an error message that relates + * to the current chunk. The chunk name comes from png_ptr->chunk_name, + * this is used to prefix the message. The message is limited in length + * to 63 bytes, the name characters are output as hex digits wrapped in [] + * if the character is invalid. + */ +#define isnonalpha(c) ((c) < 65 || (c) > 122 || ((c) > 90 && (c) < 97)) +static PNG_CONST char png_digit[16] = { + '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', + 'A', 'B', 'C', 'D', 'E', 'F' +}; + +#define PNG_MAX_ERROR_TEXT 64 +#if defined(PNG_WARNINGS_SUPPORTED) || defined(PNG_ERROR_TEXT_SUPPORTED) +static void /* PRIVATE */ +png_format_buffer(png_structp png_ptr, png_charp buffer, png_const_charp + error_message) +{ + int iout = 0, iin = 0; + + while (iin < 4) + { + int c = png_ptr->chunk_name[iin++]; + if (isnonalpha(c)) + { + buffer[iout++] = PNG_LITERAL_LEFT_SQUARE_BRACKET; + buffer[iout++] = png_digit[(c & 0xf0) >> 4]; + buffer[iout++] = png_digit[c & 0x0f]; + buffer[iout++] = PNG_LITERAL_RIGHT_SQUARE_BRACKET; + } + else + { + buffer[iout++] = (png_byte)c; + } + } + + if (error_message == NULL) + buffer[iout] = '\0'; + else + { + buffer[iout++] = ':'; + buffer[iout++] = ' '; + png_memcpy(buffer + iout, error_message, PNG_MAX_ERROR_TEXT); + buffer[iout + PNG_MAX_ERROR_TEXT - 1] = '\0'; + } +} + +#ifdef PNG_READ_SUPPORTED +void PNGAPI +png_chunk_error(png_structp png_ptr, png_const_charp error_message) +{ + char msg[18+PNG_MAX_ERROR_TEXT]; + if (png_ptr == NULL) + png_error(png_ptr, error_message); + else + { + png_format_buffer(png_ptr, msg, error_message); + png_error(png_ptr, msg); + } +} +#endif /* PNG_READ_SUPPORTED */ +#endif /* PNG_WARNINGS_SUPPORTED || PNG_ERROR_TEXT_SUPPORTED */ + +#ifdef PNG_WARNINGS_SUPPORTED +void PNGAPI +png_chunk_warning(png_structp png_ptr, png_const_charp warning_message) +{ + char msg[18+PNG_MAX_ERROR_TEXT]; + if (png_ptr == NULL) + png_warning(png_ptr, warning_message); + else + { + png_format_buffer(png_ptr, msg, warning_message); + png_warning(png_ptr, msg); + } +} +#endif /* PNG_WARNINGS_SUPPORTED */ + +#ifdef PNG_READ_SUPPORTED +#ifdef PNG_BENIGN_ERRORS_SUPPORTED +void PNGAPI +png_chunk_benign_error(png_structp png_ptr, png_const_charp error_message) +{ + if (png_ptr->flags & PNG_FLAG_BENIGN_ERRORS_WARN) + png_chunk_warning(png_ptr, error_message); + else + png_chunk_error(png_ptr, error_message); +} +#endif +#endif /* PNG_READ_SUPPORTED */ + +#ifdef PNG_SETJMP_SUPPORTED +/* This API only exists if ANSI-C style error handling is used, + * otherwise it is necessary for png_default_error to be overridden. + */ +jmp_buf* PNGAPI +png_set_longjmp_fn(png_structp png_ptr, png_longjmp_ptr longjmp_fn, + size_t jmp_buf_size) +{ + if (png_ptr == NULL || jmp_buf_size != png_sizeof(jmp_buf)) + return NULL; + + png_ptr->longjmp_fn = longjmp_fn; + return &png_ptr->jmpbuf; +} +#endif + +/* This is the default error handling function. Note that replacements for + * this function MUST NOT RETURN, or the program will likely crash. This + * function is used by default, or if the program supplies NULL for the + * error function pointer in png_set_error_fn(). + */ +static void /* PRIVATE */ +png_default_error(png_structp png_ptr, png_const_charp error_message) +{ +#ifdef PNG_CONSOLE_IO_SUPPORTED +#ifdef PNG_ERROR_NUMBERS_SUPPORTED + if (*error_message == PNG_LITERAL_SHARP) + { + /* Strip "#nnnn " from beginning of error message. */ + int offset; + char error_number[16]; + for (offset = 0; offset<15; offset++) + { + error_number[offset] = error_message[offset + 1]; + if (error_message[offset] == ' ') + break; + } + if ((offset > 1) && (offset < 15)) + { + error_number[offset - 1] = '\0'; + fprintf(stderr, "libpng error no. %s: %s", + error_number, error_message + offset + 1); + fprintf(stderr, PNG_STRING_NEWLINE); + } + else + { + fprintf(stderr, "libpng error: %s, offset=%d", + error_message, offset); + fprintf(stderr, PNG_STRING_NEWLINE); + } + } + else +#endif + { + fprintf(stderr, "libpng error: %s", error_message); + fprintf(stderr, PNG_STRING_NEWLINE); + } +#endif + +#ifdef PNG_SETJMP_SUPPORTED + if (png_ptr && png_ptr->longjmp_fn) + { +# ifdef USE_FAR_KEYWORD + { + jmp_buf jmpbuf; + png_memcpy(jmpbuf, png_ptr->jmpbuf, png_sizeof(jmp_buf)); + png_ptr->longjmp_fn(jmpbuf, 1); + } +# else + png_ptr->longjmp_fn(png_ptr->jmpbuf, 1); +# endif + } +#endif + /* Here if not setjmp support or if png_ptr is null. */ + PNG_ABORT(); +#ifndef PNG_CONSOLE_IO_SUPPORTED + error_message = error_message; /* Make compiler happy */ +#endif +} + +#ifdef PNG_WARNINGS_SUPPORTED +/* This function is called when there is a warning, but the library thinks + * it can continue anyway. Replacement functions don't have to do anything + * here if you don't want them to. In the default configuration, png_ptr is + * not used, but it is passed in case it may be useful. + */ +static void /* PRIVATE */ +png_default_warning(png_structp png_ptr, png_const_charp warning_message) +{ +#ifdef PNG_CONSOLE_IO_SUPPORTED +# ifdef PNG_ERROR_NUMBERS_SUPPORTED + if (*warning_message == PNG_LITERAL_SHARP) + { + int offset; + char warning_number[16]; + for (offset = 0; offset < 15; offset++) + { + warning_number[offset] = warning_message[offset + 1]; + if (warning_message[offset] == ' ') + break; + } + if ((offset > 1) && (offset < 15)) + { + warning_number[offset + 1] = '\0'; + fprintf(stderr, "libpng warning no. %s: %s", + warning_number, warning_message + offset); + fprintf(stderr, PNG_STRING_NEWLINE); + } + else + { + fprintf(stderr, "libpng warning: %s", + warning_message); + fprintf(stderr, PNG_STRING_NEWLINE); + } + } + else +# endif + { + fprintf(stderr, "libpng warning: %s", warning_message); + fprintf(stderr, PNG_STRING_NEWLINE); + } +#else + warning_message = warning_message; /* Make compiler happy */ +#endif + png_ptr = png_ptr; /* Make compiler happy */ +} +#endif /* PNG_WARNINGS_SUPPORTED */ + +/* This function is called when the application wants to use another method + * of handling errors and warnings. Note that the error function MUST NOT + * return to the calling routine or serious problems will occur. The return + * method used in the default routine calls longjmp(png_ptr->jmpbuf, 1) + */ +void PNGAPI +png_set_error_fn(png_structp png_ptr, png_voidp error_ptr, + png_error_ptr error_fn, png_error_ptr warning_fn) +{ + if (png_ptr == NULL) + return; + png_ptr->error_ptr = error_ptr; + png_ptr->error_fn = error_fn; + png_ptr->warning_fn = warning_fn; +} + + +/* This function returns a pointer to the error_ptr associated with the user + * functions. The application should free any memory associated with this + * pointer before png_write_destroy and png_read_destroy are called. + */ +png_voidp PNGAPI +png_get_error_ptr(png_structp png_ptr) +{ + if (png_ptr == NULL) + return NULL; + return ((png_voidp)png_ptr->error_ptr); +} + + +#ifdef PNG_ERROR_NUMBERS_SUPPORTED +void PNGAPI +png_set_strip_error_numbers(png_structp png_ptr, png_uint_32 strip_mode) +{ + if (png_ptr != NULL) + { + png_ptr->flags &= + ((~(PNG_FLAG_STRIP_ERROR_NUMBERS|PNG_FLAG_STRIP_ERROR_TEXT))&strip_mode); + } +} +#endif +#endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */ diff --git a/libpng/pngget.c b/libpng/pngget.c new file mode 100644 index 0000000..abe721b --- /dev/null +++ b/libpng/pngget.c @@ -0,0 +1,925 @@ + +/* pngget.c - retrieval of values from info struct + * + * Last changed in libpng 1.4.2 [May 6, 2010] + * Copyright (c) 1998-2010 Glenn Randers-Pehrson + * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) + * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) + * + * This code is released under the libpng license. + * For conditions of distribution and use, see the disclaimer + * and license in png.h + * + */ + +#define PNG_NO_PEDANTIC_WARNINGS +#include "png.h" +#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED) +#include "pngpriv.h" + +png_uint_32 PNGAPI +png_get_valid(png_structp png_ptr, png_infop info_ptr, png_uint_32 flag) +{ + if (png_ptr != NULL && info_ptr != NULL) + return(info_ptr->valid & flag); + + else + return(0); +} + +png_size_t PNGAPI +png_get_rowbytes(png_structp png_ptr, png_infop info_ptr) +{ + if (png_ptr != NULL && info_ptr != NULL) + return(info_ptr->rowbytes); + + else + return(0); +} + +#ifdef PNG_INFO_IMAGE_SUPPORTED +png_bytepp PNGAPI +png_get_rows(png_structp png_ptr, png_infop info_ptr) +{ + if (png_ptr != NULL && info_ptr != NULL) + return(info_ptr->row_pointers); + + else + return(0); +} +#endif + +#ifdef PNG_EASY_ACCESS_SUPPORTED +/* Easy access to info, added in libpng-0.99 */ +png_uint_32 PNGAPI +png_get_image_width(png_structp png_ptr, png_infop info_ptr) +{ + if (png_ptr != NULL && info_ptr != NULL) + return info_ptr->width; + + return (0); +} + +png_uint_32 PNGAPI +png_get_image_height(png_structp png_ptr, png_infop info_ptr) +{ + if (png_ptr != NULL && info_ptr != NULL) + return info_ptr->height; + + return (0); +} + +png_byte PNGAPI +png_get_bit_depth(png_structp png_ptr, png_infop info_ptr) +{ + if (png_ptr != NULL && info_ptr != NULL) + return info_ptr->bit_depth; + + return (0); +} + +png_byte PNGAPI +png_get_color_type(png_structp png_ptr, png_infop info_ptr) +{ + if (png_ptr != NULL && info_ptr != NULL) + return info_ptr->color_type; + + return (0); +} + +png_byte PNGAPI +png_get_filter_type(png_structp png_ptr, png_infop info_ptr) +{ + if (png_ptr != NULL && info_ptr != NULL) + return info_ptr->filter_type; + + return (0); +} + +png_byte PNGAPI +png_get_interlace_type(png_structp png_ptr, png_infop info_ptr) +{ + if (png_ptr != NULL && info_ptr != NULL) + return info_ptr->interlace_type; + + return (0); +} + +png_byte PNGAPI +png_get_compression_type(png_structp png_ptr, png_infop info_ptr) +{ + if (png_ptr != NULL && info_ptr != NULL) + return info_ptr->compression_type; + + return (0); +} + +png_uint_32 PNGAPI +png_get_x_pixels_per_meter(png_structp png_ptr, png_infop info_ptr) +{ + if (png_ptr != NULL && info_ptr != NULL) +#ifdef PNG_pHYs_SUPPORTED + if (info_ptr->valid & PNG_INFO_pHYs) + { + png_debug1(1, "in %s retrieval function", "png_get_x_pixels_per_meter"); + + if (info_ptr->phys_unit_type != PNG_RESOLUTION_METER) + return (0); + + else + return (info_ptr->x_pixels_per_unit); + } +#else + return (0); +#endif + return (0); +} + +png_uint_32 PNGAPI +png_get_y_pixels_per_meter(png_structp png_ptr, png_infop info_ptr) +{ + if (png_ptr != NULL && info_ptr != NULL) +#ifdef PNG_pHYs_SUPPORTED + if (info_ptr->valid & PNG_INFO_pHYs) + { + png_debug1(1, "in %s retrieval function", "png_get_y_pixels_per_meter"); + + if (info_ptr->phys_unit_type != PNG_RESOLUTION_METER) + return (0); + + else + return (info_ptr->y_pixels_per_unit); + } +#else + return (0); +#endif + return (0); +} + +png_uint_32 PNGAPI +png_get_pixels_per_meter(png_structp png_ptr, png_infop info_ptr) +{ + if (png_ptr != NULL && info_ptr != NULL) +#ifdef PNG_pHYs_SUPPORTED + if (info_ptr->valid & PNG_INFO_pHYs) + { + png_debug1(1, "in %s retrieval function", "png_get_pixels_per_meter"); + + if (info_ptr->phys_unit_type != PNG_RESOLUTION_METER || + info_ptr->x_pixels_per_unit != info_ptr->y_pixels_per_unit) + return (0); + + else + return (info_ptr->x_pixels_per_unit); + } +#else + return (0); +#endif + return (0); +} + +#ifdef PNG_FLOATING_POINT_SUPPORTED +float PNGAPI +png_get_pixel_aspect_ratio(png_structp png_ptr, png_infop info_ptr) + { + if (png_ptr != NULL && info_ptr != NULL) +#ifdef PNG_pHYs_SUPPORTED + + if (info_ptr->valid & PNG_INFO_pHYs) + { + png_debug1(1, "in %s retrieval function", "png_get_aspect_ratio"); + + if (info_ptr->x_pixels_per_unit == 0) + return ((float)0.0); + + else + return ((float)((float)info_ptr->y_pixels_per_unit + /(float)info_ptr->x_pixels_per_unit)); + } +#else + return (0.0); +#endif + return ((float)0.0); +} +#endif + +png_int_32 PNGAPI +png_get_x_offset_microns(png_structp png_ptr, png_infop info_ptr) +{ + if (png_ptr != NULL && info_ptr != NULL) +#ifdef PNG_oFFs_SUPPORTED + + if (info_ptr->valid & PNG_INFO_oFFs) + { + png_debug1(1, "in %s retrieval function", "png_get_x_offset_microns"); + + if (info_ptr->offset_unit_type != PNG_OFFSET_MICROMETER) + return (0); + + else + return (info_ptr->x_offset); + } +#else + return (0); +#endif + return (0); +} + +png_int_32 PNGAPI +png_get_y_offset_microns(png_structp png_ptr, png_infop info_ptr) +{ + if (png_ptr != NULL && info_ptr != NULL) + +#ifdef PNG_oFFs_SUPPORTED + if (info_ptr->valid & PNG_INFO_oFFs) + { + png_debug1(1, "in %s retrieval function", "png_get_y_offset_microns"); + + if (info_ptr->offset_unit_type != PNG_OFFSET_MICROMETER) + return (0); + + else + return (info_ptr->y_offset); + } +#else + return (0); +#endif + return (0); +} + +png_int_32 PNGAPI +png_get_x_offset_pixels(png_structp png_ptr, png_infop info_ptr) +{ + if (png_ptr != NULL && info_ptr != NULL) + +#ifdef PNG_oFFs_SUPPORTED + if (info_ptr->valid & PNG_INFO_oFFs) + { + png_debug1(1, "in %s retrieval function", "png_get_x_offset_microns"); + + if (info_ptr->offset_unit_type != PNG_OFFSET_PIXEL) + return (0); + + else + return (info_ptr->x_offset); + } +#else + return (0); +#endif + return (0); +} + +png_int_32 PNGAPI +png_get_y_offset_pixels(png_structp png_ptr, png_infop info_ptr) +{ + if (png_ptr != NULL && info_ptr != NULL) + +#ifdef PNG_oFFs_SUPPORTED + if (info_ptr->valid & PNG_INFO_oFFs) + { + png_debug1(1, "in %s retrieval function", "png_get_y_offset_microns"); + + if (info_ptr->offset_unit_type != PNG_OFFSET_PIXEL) + return (0); + + else + return (info_ptr->y_offset); + } +#else + return (0); +#endif + return (0); +} + +#if defined(PNG_INCH_CONVERSIONS) && defined(PNG_FLOATING_POINT_SUPPORTED) +png_uint_32 PNGAPI +png_get_pixels_per_inch(png_structp png_ptr, png_infop info_ptr) +{ + return ((png_uint_32)((float)png_get_pixels_per_meter(png_ptr, info_ptr) + *.0254 +.5)); +} + +png_uint_32 PNGAPI +png_get_x_pixels_per_inch(png_structp png_ptr, png_infop info_ptr) +{ + return ((png_uint_32)((float)png_get_x_pixels_per_meter(png_ptr, info_ptr) + *.0254 +.5)); +} + +png_uint_32 PNGAPI +png_get_y_pixels_per_inch(png_structp png_ptr, png_infop info_ptr) +{ + return ((png_uint_32)((float)png_get_y_pixels_per_meter(png_ptr, info_ptr) + *.0254 +.5)); +} + +float PNGAPI +png_get_x_offset_inches(png_structp png_ptr, png_infop info_ptr) +{ + return ((float)png_get_x_offset_microns(png_ptr, info_ptr) + *.00003937); +} + +float PNGAPI +png_get_y_offset_inches(png_structp png_ptr, png_infop info_ptr) +{ + return ((float)png_get_y_offset_microns(png_ptr, info_ptr) + *.00003937); +} + +#ifdef PNG_pHYs_SUPPORTED +png_uint_32 PNGAPI +png_get_pHYs_dpi(png_structp png_ptr, png_infop info_ptr, + png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type) +{ + png_uint_32 retval = 0; + + if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs)) + { + png_debug1(1, "in %s retrieval function", "pHYs"); + + if (res_x != NULL) + { + *res_x = info_ptr->x_pixels_per_unit; + retval |= PNG_INFO_pHYs; + } + if (res_y != NULL) + { + *res_y = info_ptr->y_pixels_per_unit; + retval |= PNG_INFO_pHYs; + } + if (unit_type != NULL) + { + *unit_type = (int)info_ptr->phys_unit_type; + retval |= PNG_INFO_pHYs; + if (*unit_type == 1) + { + if (res_x != NULL) *res_x = (png_uint_32)(*res_x * .0254 + .50); + if (res_y != NULL) *res_y = (png_uint_32)(*res_y * .0254 + .50); + } + } + } + return (retval); +} +#endif /* PNG_pHYs_SUPPORTED */ +#endif /* PNG_INCH_CONVERSIONS && PNG_FLOATING_POINT_SUPPORTED */ + +/* png_get_channels really belongs in here, too, but it's been around longer */ + +#endif /* PNG_EASY_ACCESS_SUPPORTED */ + +png_byte PNGAPI +png_get_channels(png_structp png_ptr, png_infop info_ptr) +{ + if (png_ptr != NULL && info_ptr != NULL) + return(info_ptr->channels); + else + return (0); +} + +png_bytep PNGAPI +png_get_signature(png_structp png_ptr, png_infop info_ptr) +{ + if (png_ptr != NULL && info_ptr != NULL) + return(info_ptr->signature); + else + return (NULL); +} + +#ifdef PNG_bKGD_SUPPORTED +png_uint_32 PNGAPI +png_get_bKGD(png_structp png_ptr, png_infop info_ptr, + png_color_16p *background) +{ + if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_bKGD) + && background != NULL) + { + png_debug1(1, "in %s retrieval function", "bKGD"); + + *background = &(info_ptr->background); + return (PNG_INFO_bKGD); + } + return (0); +} +#endif + +#ifdef PNG_cHRM_SUPPORTED +#ifdef PNG_FLOATING_POINT_SUPPORTED +png_uint_32 PNGAPI +png_get_cHRM(png_structp png_ptr, png_infop info_ptr, + double *white_x, double *white_y, double *red_x, double *red_y, + double *green_x, double *green_y, double *blue_x, double *blue_y) +{ + if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_cHRM)) + { + png_debug1(1, "in %s retrieval function", "cHRM"); + + if (white_x != NULL) + *white_x = (double)info_ptr->x_white; + if (white_y != NULL) + *white_y = (double)info_ptr->y_white; + if (red_x != NULL) + *red_x = (double)info_ptr->x_red; + if (red_y != NULL) + *red_y = (double)info_ptr->y_red; + if (green_x != NULL) + *green_x = (double)info_ptr->x_green; + if (green_y != NULL) + *green_y = (double)info_ptr->y_green; + if (blue_x != NULL) + *blue_x = (double)info_ptr->x_blue; + if (blue_y != NULL) + *blue_y = (double)info_ptr->y_blue; + return (PNG_INFO_cHRM); + } + return (0); +} +#endif +#ifdef PNG_FIXED_POINT_SUPPORTED +png_uint_32 PNGAPI +png_get_cHRM_fixed(png_structp png_ptr, png_infop info_ptr, + png_fixed_point *white_x, png_fixed_point *white_y, png_fixed_point *red_x, + png_fixed_point *red_y, png_fixed_point *green_x, png_fixed_point *green_y, + png_fixed_point *blue_x, png_fixed_point *blue_y) +{ + png_debug1(1, "in %s retrieval function", "cHRM"); + + if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_cHRM)) + { + if (white_x != NULL) + *white_x = info_ptr->int_x_white; + if (white_y != NULL) + *white_y = info_ptr->int_y_white; + if (red_x != NULL) + *red_x = info_ptr->int_x_red; + if (red_y != NULL) + *red_y = info_ptr->int_y_red; + if (green_x != NULL) + *green_x = info_ptr->int_x_green; + if (green_y != NULL) + *green_y = info_ptr->int_y_green; + if (blue_x != NULL) + *blue_x = info_ptr->int_x_blue; + if (blue_y != NULL) + *blue_y = info_ptr->int_y_blue; + return (PNG_INFO_cHRM); + } + return (0); +} +#endif +#endif + +#ifdef PNG_gAMA_SUPPORTED +#ifdef PNG_FLOATING_POINT_SUPPORTED +png_uint_32 PNGAPI +png_get_gAMA(png_structp png_ptr, png_infop info_ptr, double *file_gamma) +{ + png_debug1(1, "in %s retrieval function", "gAMA"); + + if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_gAMA) + && file_gamma != NULL) + { + *file_gamma = (double)info_ptr->gamma; + return (PNG_INFO_gAMA); + } + return (0); +} +#endif +#ifdef PNG_FIXED_POINT_SUPPORTED +png_uint_32 PNGAPI +png_get_gAMA_fixed(png_structp png_ptr, png_infop info_ptr, + png_fixed_point *int_file_gamma) +{ + png_debug1(1, "in %s retrieval function", "gAMA"); + + if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_gAMA) + && int_file_gamma != NULL) + { + *int_file_gamma = info_ptr->int_gamma; + return (PNG_INFO_gAMA); + } + return (0); +} +#endif +#endif + +#ifdef PNG_sRGB_SUPPORTED +png_uint_32 PNGAPI +png_get_sRGB(png_structp png_ptr, png_infop info_ptr, int *file_srgb_intent) +{ + png_debug1(1, "in %s retrieval function", "sRGB"); + + if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_sRGB) + && file_srgb_intent != NULL) + { + *file_srgb_intent = (int)info_ptr->srgb_intent; + return (PNG_INFO_sRGB); + } + return (0); +} +#endif + +#ifdef PNG_iCCP_SUPPORTED +png_uint_32 PNGAPI +png_get_iCCP(png_structp png_ptr, png_infop info_ptr, + png_charpp name, int *compression_type, + png_charpp profile, png_uint_32 *proflen) +{ + png_debug1(1, "in %s retrieval function", "iCCP"); + + if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_iCCP) + && name != NULL && profile != NULL && proflen != NULL) + { + *name = info_ptr->iccp_name; + *profile = info_ptr->iccp_profile; + /* Compression_type is a dummy so the API won't have to change + * if we introduce multiple compression types later. + */ + *proflen = (int)info_ptr->iccp_proflen; + *compression_type = (int)info_ptr->iccp_compression; + return (PNG_INFO_iCCP); + } + return (0); +} +#endif + +#ifdef PNG_sPLT_SUPPORTED +png_uint_32 PNGAPI +png_get_sPLT(png_structp png_ptr, png_infop info_ptr, + png_sPLT_tpp spalettes) +{ + if (png_ptr != NULL && info_ptr != NULL && spalettes != NULL) + { + *spalettes = info_ptr->splt_palettes; + return ((png_uint_32)info_ptr->splt_palettes_num); + } + return (0); +} +#endif + +#ifdef PNG_hIST_SUPPORTED +png_uint_32 PNGAPI +png_get_hIST(png_structp png_ptr, png_infop info_ptr, png_uint_16p *hist) +{ + png_debug1(1, "in %s retrieval function", "hIST"); + + if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_hIST) + && hist != NULL) + { + *hist = info_ptr->hist; + return (PNG_INFO_hIST); + } + return (0); +} +#endif + +png_uint_32 PNGAPI +png_get_IHDR(png_structp png_ptr, png_infop info_ptr, + png_uint_32 *width, png_uint_32 *height, int *bit_depth, + int *color_type, int *interlace_type, int *compression_type, + int *filter_type) + +{ + png_debug1(1, "in %s retrieval function", "IHDR"); + + if (png_ptr == NULL || info_ptr == NULL || width == NULL || + height == NULL || bit_depth == NULL || color_type == NULL) + return (0); + + *width = info_ptr->width; + *height = info_ptr->height; + *bit_depth = info_ptr->bit_depth; + *color_type = info_ptr->color_type; + + if (compression_type != NULL) + *compression_type = info_ptr->compression_type; + + if (filter_type != NULL) + *filter_type = info_ptr->filter_type; + + if (interlace_type != NULL) + *interlace_type = info_ptr->interlace_type; + + /* This is redundant if we can be sure that the info_ptr values were all + * assigned in png_set_IHDR(). We do the check anyhow in case an + * application has ignored our advice not to mess with the members + * of info_ptr directly. + */ + png_check_IHDR (png_ptr, info_ptr->width, info_ptr->height, + info_ptr->bit_depth, info_ptr->color_type, info_ptr->interlace_type, + info_ptr->compression_type, info_ptr->filter_type); + + return (1); +} + +#ifdef PNG_oFFs_SUPPORTED +png_uint_32 PNGAPI +png_get_oFFs(png_structp png_ptr, png_infop info_ptr, + png_int_32 *offset_x, png_int_32 *offset_y, int *unit_type) +{ + png_debug1(1, "in %s retrieval function", "oFFs"); + + if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs) + && offset_x != NULL && offset_y != NULL && unit_type != NULL) + { + *offset_x = info_ptr->x_offset; + *offset_y = info_ptr->y_offset; + *unit_type = (int)info_ptr->offset_unit_type; + return (PNG_INFO_oFFs); + } + return (0); +} +#endif + +#ifdef PNG_pCAL_SUPPORTED +png_uint_32 PNGAPI +png_get_pCAL(png_structp png_ptr, png_infop info_ptr, + png_charp *purpose, png_int_32 *X0, png_int_32 *X1, int *type, int *nparams, + png_charp *units, png_charpp *params) +{ + png_debug1(1, "in %s retrieval function", "pCAL"); + + if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pCAL) + && purpose != NULL && X0 != NULL && X1 != NULL && type != NULL && + nparams != NULL && units != NULL && params != NULL) + { + *purpose = info_ptr->pcal_purpose; + *X0 = info_ptr->pcal_X0; + *X1 = info_ptr->pcal_X1; + *type = (int)info_ptr->pcal_type; + *nparams = (int)info_ptr->pcal_nparams; + *units = info_ptr->pcal_units; + *params = info_ptr->pcal_params; + return (PNG_INFO_pCAL); + } + return (0); +} +#endif + +#ifdef PNG_sCAL_SUPPORTED +#ifdef PNG_FLOATING_POINT_SUPPORTED +png_uint_32 PNGAPI +png_get_sCAL(png_structp png_ptr, png_infop info_ptr, + int *unit, double *width, double *height) +{ + if (png_ptr != NULL && info_ptr != NULL && + (info_ptr->valid & PNG_INFO_sCAL)) + { + *unit = info_ptr->scal_unit; + *width = info_ptr->scal_pixel_width; + *height = info_ptr->scal_pixel_height; + return (PNG_INFO_sCAL); + } + return(0); +} +#else +#ifdef PNG_FIXED_POINT_SUPPORTED +png_uint_32 PNGAPI +png_get_sCAL_s(png_structp png_ptr, png_infop info_ptr, + int *unit, png_charpp width, png_charpp height) +{ + if (png_ptr != NULL && info_ptr != NULL && + (info_ptr->valid & PNG_INFO_sCAL)) + { + *unit = info_ptr->scal_unit; + *width = info_ptr->scal_s_width; + *height = info_ptr->scal_s_height; + return (PNG_INFO_sCAL); + } + return(0); +} +#endif +#endif +#endif + +#ifdef PNG_pHYs_SUPPORTED +png_uint_32 PNGAPI +png_get_pHYs(png_structp png_ptr, png_infop info_ptr, + png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type) +{ + png_uint_32 retval = 0; + + png_debug1(1, "in %s retrieval function", "pHYs"); + + if (png_ptr != NULL && info_ptr != NULL && + (info_ptr->valid & PNG_INFO_pHYs)) + { + if (res_x != NULL) + { + *res_x = info_ptr->x_pixels_per_unit; + retval |= PNG_INFO_pHYs; + } + + if (res_y != NULL) + { + *res_y = info_ptr->y_pixels_per_unit; + retval |= PNG_INFO_pHYs; + } + + if (unit_type != NULL) + { + *unit_type = (int)info_ptr->phys_unit_type; + retval |= PNG_INFO_pHYs; + } + } + return (retval); +} +#endif + +png_uint_32 PNGAPI +png_get_PLTE(png_structp png_ptr, png_infop info_ptr, png_colorp *palette, + int *num_palette) +{ + png_debug1(1, "in %s retrieval function", "PLTE"); + + if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_PLTE) + && palette != NULL) + { + *palette = info_ptr->palette; + *num_palette = info_ptr->num_palette; + png_debug1(3, "num_palette = %d", *num_palette); + return (PNG_INFO_PLTE); + } + return (0); +} + +#ifdef PNG_sBIT_SUPPORTED +png_uint_32 PNGAPI +png_get_sBIT(png_structp png_ptr, png_infop info_ptr, png_color_8p *sig_bit) +{ + png_debug1(1, "in %s retrieval function", "sBIT"); + + if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_sBIT) + && sig_bit != NULL) + { + *sig_bit = &(info_ptr->sig_bit); + return (PNG_INFO_sBIT); + } + return (0); +} +#endif + +#ifdef PNG_TEXT_SUPPORTED +png_uint_32 PNGAPI +png_get_text(png_structp png_ptr, png_infop info_ptr, png_textp *text_ptr, + int *num_text) +{ + if (png_ptr != NULL && info_ptr != NULL && info_ptr->num_text > 0) + { + png_debug1(1, "in %s retrieval function", + (png_ptr->chunk_name[0] == '\0' ? "text" + : (png_const_charp)png_ptr->chunk_name)); + + if (text_ptr != NULL) + *text_ptr = info_ptr->text; + + if (num_text != NULL) + *num_text = info_ptr->num_text; + + return ((png_uint_32)info_ptr->num_text); + } + if (num_text != NULL) + *num_text = 0; + return(0); +} +#endif + +#ifdef PNG_tIME_SUPPORTED +png_uint_32 PNGAPI +png_get_tIME(png_structp png_ptr, png_infop info_ptr, png_timep *mod_time) +{ + png_debug1(1, "in %s retrieval function", "tIME"); + + if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_tIME) + && mod_time != NULL) + { + *mod_time = &(info_ptr->mod_time); + return (PNG_INFO_tIME); + } + return (0); +} +#endif + +#ifdef PNG_tRNS_SUPPORTED +png_uint_32 PNGAPI +png_get_tRNS(png_structp png_ptr, png_infop info_ptr, + png_bytep *trans_alpha, int *num_trans, png_color_16p *trans_color) +{ + png_uint_32 retval = 0; + if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_tRNS)) + { + png_debug1(1, "in %s retrieval function", "tRNS"); + + if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE) + { + if (trans_alpha != NULL) + { + *trans_alpha = info_ptr->trans_alpha; + retval |= PNG_INFO_tRNS; + } + + if (trans_color != NULL) + *trans_color = &(info_ptr->trans_color); + } + else /* if (info_ptr->color_type != PNG_COLOR_TYPE_PALETTE) */ + { + if (trans_color != NULL) + { + *trans_color = &(info_ptr->trans_color); + retval |= PNG_INFO_tRNS; + } + + if (trans_alpha != NULL) + *trans_alpha = NULL; + } + if (num_trans != NULL) + { + *num_trans = info_ptr->num_trans; + retval |= PNG_INFO_tRNS; + } + } + return (retval); +} +#endif + +#ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED +png_uint_32 PNGAPI +png_get_unknown_chunks(png_structp png_ptr, png_infop info_ptr, + png_unknown_chunkpp unknowns) +{ + if (png_ptr != NULL && info_ptr != NULL && unknowns != NULL) + { + *unknowns = info_ptr->unknown_chunks; + return ((png_uint_32)info_ptr->unknown_chunks_num); + } + return (0); +} +#endif + +#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED +png_byte PNGAPI +png_get_rgb_to_gray_status (png_structp png_ptr) +{ + return (png_byte)(png_ptr? png_ptr->rgb_to_gray_status : 0); +} +#endif + +#ifdef PNG_USER_CHUNKS_SUPPORTED +png_voidp PNGAPI +png_get_user_chunk_ptr(png_structp png_ptr) +{ + return (png_ptr? png_ptr->user_chunk_ptr : NULL); +} +#endif + +png_size_t PNGAPI +png_get_compression_buffer_size(png_structp png_ptr) +{ + return (png_ptr ? png_ptr->zbuf_size : 0L); +} + + +#ifdef PNG_SET_USER_LIMITS_SUPPORTED +/* These functions were added to libpng 1.2.6 and were enabled + * by default in libpng-1.4.0 */ +png_uint_32 PNGAPI +png_get_user_width_max (png_structp png_ptr) +{ + return (png_ptr? png_ptr->user_width_max : 0); +} +png_uint_32 PNGAPI +png_get_user_height_max (png_structp png_ptr) +{ + return (png_ptr? png_ptr->user_height_max : 0); +} +/* This function was added to libpng 1.4.0 */ +png_uint_32 PNGAPI +png_get_chunk_cache_max (png_structp png_ptr) +{ + return (png_ptr? png_ptr->user_chunk_cache_max : 0); +} +/* This function was added to libpng 1.4.1 */ +png_alloc_size_t PNGAPI +png_get_chunk_malloc_max (png_structp png_ptr) +{ + return (png_ptr? + png_ptr->user_chunk_malloc_max : 0); +} +#endif /* ?PNG_SET_USER_LIMITS_SUPPORTED */ + +/* These functions were added to libpng 1.4.0 */ +#ifdef PNG_IO_STATE_SUPPORTED +png_uint_32 PNGAPI +png_get_io_state (png_structp png_ptr) +{ + return png_ptr->io_state; +} + +png_bytep PNGAPI +png_get_io_chunk_name (png_structp png_ptr) +{ + return png_ptr->chunk_name; +} +#endif /* ?PNG_IO_STATE_SUPPORTED */ + +#endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */ diff --git a/libpng/pngmem.c b/libpng/pngmem.c new file mode 100644 index 0000000..c8a3f6f --- /dev/null +++ b/libpng/pngmem.c @@ -0,0 +1,611 @@ + +/* pngmem.c - stub functions for memory allocation + * + * Last changed in libpng 1.4.2 [May 6, 2010] + * Copyright (c) 1998-2010 Glenn Randers-Pehrson + * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) + * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) + * + * This code is released under the libpng license. + * For conditions of distribution and use, see the disclaimer + * and license in png.h + * + * This file provides a location for all memory allocation. Users who + * need special memory handling are expected to supply replacement + * functions for png_malloc() and png_free(), and to use + * png_create_read_struct_2() and png_create_write_struct_2() to + * identify the replacement functions. + */ + +#define PNG_NO_PEDANTIC_WARNINGS +#include "png.h" +#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED) +#include "pngpriv.h" + +/* Borland DOS special memory handler */ +#if defined(__TURBOC__) && !defined(_Windows) && !defined(__FLAT__) +/* If you change this, be sure to change the one in png.h also */ + +/* Allocate memory for a png_struct. The malloc and memset can be replaced + by a single call to calloc() if this is thought to improve performance. */ +png_voidp /* PRIVATE */ +png_create_struct(int type) +{ +#ifdef PNG_USER_MEM_SUPPORTED + return (png_create_struct_2(type, NULL, NULL)); +} + +/* Alternate version of png_create_struct, for use with user-defined malloc. */ +png_voidp /* PRIVATE */ +png_create_struct_2(int type, png_malloc_ptr malloc_fn, png_voidp mem_ptr) +{ +#endif /* PNG_USER_MEM_SUPPORTED */ + png_size_t size; + png_voidp struct_ptr; + + if (type == PNG_STRUCT_INFO) + size = png_sizeof(png_info); + else if (type == PNG_STRUCT_PNG) + size = png_sizeof(png_struct); + else + return (png_get_copyright(NULL)); + +#ifdef PNG_USER_MEM_SUPPORTED + if (malloc_fn != NULL) + { + png_struct dummy_struct; + png_structp png_ptr = &dummy_struct; + png_ptr->mem_ptr=mem_ptr; + struct_ptr = (*(malloc_fn))(png_ptr, (png_uint_32)size); + } + else +#endif /* PNG_USER_MEM_SUPPORTED */ + struct_ptr = (png_voidp)farmalloc(size); + if (struct_ptr != NULL) + png_memset(struct_ptr, 0, size); + return (struct_ptr); +} + +/* Free memory allocated by a png_create_struct() call */ +void /* PRIVATE */ +png_destroy_struct(png_voidp struct_ptr) +{ +#ifdef PNG_USER_MEM_SUPPORTED + png_destroy_struct_2(struct_ptr, NULL, NULL); +} + +/* Free memory allocated by a png_create_struct() call */ +void /* PRIVATE */ +png_destroy_struct_2(png_voidp struct_ptr, png_free_ptr free_fn, + png_voidp mem_ptr) +{ +#endif + if (struct_ptr != NULL) + { +#ifdef PNG_USER_MEM_SUPPORTED + if (free_fn != NULL) + { + png_struct dummy_struct; + png_structp png_ptr = &dummy_struct; + png_ptr->mem_ptr=mem_ptr; + (*(free_fn))(png_ptr, struct_ptr); + return; + } +#endif /* PNG_USER_MEM_SUPPORTED */ + farfree (struct_ptr); + } +} + +/* Allocate memory. For reasonable files, size should never exceed + * 64K. However, zlib may allocate more then 64K if you don't tell + * it not to. See zconf.h and png.h for more information. zlib does + * need to allocate exactly 64K, so whatever you call here must + * have the ability to do that. + * + * Borland seems to have a problem in DOS mode for exactly 64K. + * It gives you a segment with an offset of 8 (perhaps to store its + * memory stuff). zlib doesn't like this at all, so we have to + * detect and deal with it. This code should not be needed in + * Windows or OS/2 modes, and only in 16 bit mode. This code has + * been updated by Alexander Lehmann for version 0.89 to waste less + * memory. + * + * Note that we can't use png_size_t for the "size" declaration, + * since on some systems a png_size_t is a 16-bit quantity, and as a + * result, we would be truncating potentially larger memory requests + * (which should cause a fatal error) and introducing major problems. + */ +png_voidp PNGAPI +png_calloc(png_structp png_ptr, png_alloc_size_t size) +{ + png_voidp ret; + + ret = (png_malloc(png_ptr, size)); + if (ret != NULL) + png_memset(ret,0,(png_size_t)size); + return (ret); +} + +png_voidp PNGAPI +png_malloc(png_structp png_ptr, png_alloc_size_t size) +{ + png_voidp ret; + + if (png_ptr == NULL || size == 0) + return (NULL); + +#ifdef PNG_USER_MEM_SUPPORTED + if (png_ptr->malloc_fn != NULL) + ret = ((png_voidp)(*(png_ptr->malloc_fn))(png_ptr, (png_size_t)size)); + else + ret = (png_malloc_default(png_ptr, size)); + if (ret == NULL && (png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0) + png_error(png_ptr, "Out of memory"); + return (ret); +} + +png_voidp PNGAPI +png_malloc_default(png_structp png_ptr, png_alloc_size_t size) +{ + png_voidp ret; +#endif /* PNG_USER_MEM_SUPPORTED */ + + if (png_ptr == NULL || size == 0) + return (NULL); + +#ifdef PNG_MAX_MALLOC_64K + if (size > (png_uint_32)65536L) + { + png_warning(png_ptr, "Cannot Allocate > 64K"); + ret = NULL; + } + else +#endif + + if (size != (size_t)size) + ret = NULL; + else if (size == (png_uint_32)65536L) + { + if (png_ptr->offset_table == NULL) + { + /* Try to see if we need to do any of this fancy stuff */ + ret = farmalloc(size); + if (ret == NULL || ((png_size_t)ret & 0xffff)) + { + int num_blocks; + png_uint_32 total_size; + png_bytep table; + int i; + png_byte huge * hptr; + + if (ret != NULL) + { + farfree(ret); + ret = NULL; + } + + if (png_ptr->zlib_window_bits > 14) + num_blocks = (int)(1 << (png_ptr->zlib_window_bits - 14)); + else + num_blocks = 1; + if (png_ptr->zlib_mem_level >= 7) + num_blocks += (int)(1 << (png_ptr->zlib_mem_level - 7)); + else + num_blocks++; + + total_size = ((png_uint_32)65536L) * (png_uint_32)num_blocks+16; + + table = farmalloc(total_size); + + if (table == NULL) + { +#ifndef PNG_USER_MEM_SUPPORTED + if ((png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0) + png_error(png_ptr, "Out Of Memory"); /* Note "O", "M" */ + else + png_warning(png_ptr, "Out Of Memory"); +#endif + return (NULL); + } + + if ((png_size_t)table & 0xfff0) + { +#ifndef PNG_USER_MEM_SUPPORTED + if ((png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0) + png_error(png_ptr, + "Farmalloc didn't return normalized pointer"); + else + png_warning(png_ptr, + "Farmalloc didn't return normalized pointer"); +#endif + return (NULL); + } + + png_ptr->offset_table = table; + png_ptr->offset_table_ptr = farmalloc(num_blocks * + png_sizeof(png_bytep)); + + if (png_ptr->offset_table_ptr == NULL) + { +#ifndef PNG_USER_MEM_SUPPORTED + if ((png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0) + png_error(png_ptr, "Out Of memory"); /* Note "O", "m" */ + else + png_warning(png_ptr, "Out Of memory"); +#endif + return (NULL); + } + + hptr = (png_byte huge *)table; + if ((png_size_t)hptr & 0xf) + { + hptr = (png_byte huge *)((long)(hptr) & 0xfffffff0L); + hptr = hptr + 16L; /* "hptr += 16L" fails on Turbo C++ 3.0 */ + } + for (i = 0; i < num_blocks; i++) + { + png_ptr->offset_table_ptr[i] = (png_bytep)hptr; + hptr = hptr + (png_uint_32)65536L; /* "+=" fails on TC++3.0 */ + } + + png_ptr->offset_table_number = num_blocks; + png_ptr->offset_table_count = 0; + png_ptr->offset_table_count_free = 0; + } + } + + if (png_ptr->offset_table_count >= png_ptr->offset_table_number) + { +#ifndef PNG_USER_MEM_SUPPORTED + if ((png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0) + png_error(png_ptr, "Out of Memory"); /* Note "o" and "M" */ + else + png_warning(png_ptr, "Out of Memory"); +#endif + return (NULL); + } + + ret = png_ptr->offset_table_ptr[png_ptr->offset_table_count++]; + } + else + ret = farmalloc(size); + +#ifndef PNG_USER_MEM_SUPPORTED + if (ret == NULL) + { + if ((png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0) + png_error(png_ptr, "Out of memory"); /* Note "o" and "m" */ + else + png_warning(png_ptr, "Out of memory"); /* Note "o" and "m" */ + } +#endif + + return (ret); +} + +/* Free a pointer allocated by png_malloc(). In the default + * configuration, png_ptr is not used, but is passed in case it + * is needed. If ptr is NULL, return without taking any action. + */ +void PNGAPI +png_free(png_structp png_ptr, png_voidp ptr) +{ + if (png_ptr == NULL || ptr == NULL) + return; + +#ifdef PNG_USER_MEM_SUPPORTED + if (png_ptr->free_fn != NULL) + { + (*(png_ptr->free_fn))(png_ptr, ptr); + return; + } + else + png_free_default(png_ptr, ptr); +} + +void PNGAPI +png_free_default(png_structp png_ptr, png_voidp ptr) +{ +#endif /* PNG_USER_MEM_SUPPORTED */ + + if (png_ptr == NULL || ptr == NULL) + return; + + if (png_ptr->offset_table != NULL) + { + int i; + + for (i = 0; i < png_ptr->offset_table_count; i++) + { + if (ptr == png_ptr->offset_table_ptr[i]) + { + ptr = NULL; + png_ptr->offset_table_count_free++; + break; + } + } + if (png_ptr->offset_table_count_free == png_ptr->offset_table_count) + { + farfree(png_ptr->offset_table); + farfree(png_ptr->offset_table_ptr); + png_ptr->offset_table = NULL; + png_ptr->offset_table_ptr = NULL; + } + } + + if (ptr != NULL) + { + farfree(ptr); + } +} + +#else /* Not the Borland DOS special memory handler */ + +/* Allocate memory for a png_struct or a png_info. The malloc and + memset can be replaced by a single call to calloc() if this is thought + to improve performance noticably. */ +png_voidp /* PRIVATE */ +png_create_struct(int type) +{ +#ifdef PNG_USER_MEM_SUPPORTED + return (png_create_struct_2(type, NULL, NULL)); +} + +/* Allocate memory for a png_struct or a png_info. The malloc and + memset can be replaced by a single call to calloc() if this is thought + to improve performance noticably. */ +png_voidp /* PRIVATE */ +png_create_struct_2(int type, png_malloc_ptr malloc_fn, png_voidp mem_ptr) +{ +#endif /* PNG_USER_MEM_SUPPORTED */ + png_size_t size; + png_voidp struct_ptr; + + if (type == PNG_STRUCT_INFO) + size = png_sizeof(png_info); + else if (type == PNG_STRUCT_PNG) + size = png_sizeof(png_struct); + else + return (NULL); + +#ifdef PNG_USER_MEM_SUPPORTED + if (malloc_fn != NULL) + { + png_struct dummy_struct; + png_structp png_ptr = &dummy_struct; + png_ptr->mem_ptr=mem_ptr; + struct_ptr = (*(malloc_fn))(png_ptr, size); + if (struct_ptr != NULL) + png_memset(struct_ptr, 0, size); + return (struct_ptr); + } +#endif /* PNG_USER_MEM_SUPPORTED */ + +#if defined(__TURBOC__) && !defined(__FLAT__) + struct_ptr = (png_voidp)farmalloc(size); +#else +# if defined(_MSC_VER) && defined(MAXSEG_64K) + struct_ptr = (png_voidp)halloc(size, 1); +# else + struct_ptr = (png_voidp)malloc(size); +# endif +#endif + if (struct_ptr != NULL) + png_memset(struct_ptr, 0, size); + + return (struct_ptr); +} + + +/* Free memory allocated by a png_create_struct() call */ +void /* PRIVATE */ +png_destroy_struct(png_voidp struct_ptr) +{ +#ifdef PNG_USER_MEM_SUPPORTED + png_destroy_struct_2(struct_ptr, NULL, NULL); +} + +/* Free memory allocated by a png_create_struct() call */ +void /* PRIVATE */ +png_destroy_struct_2(png_voidp struct_ptr, png_free_ptr free_fn, + png_voidp mem_ptr) +{ +#endif /* PNG_USER_MEM_SUPPORTED */ + if (struct_ptr != NULL) + { +#ifdef PNG_USER_MEM_SUPPORTED + if (free_fn != NULL) + { + png_struct dummy_struct; + png_structp png_ptr = &dummy_struct; + png_ptr->mem_ptr=mem_ptr; + (*(free_fn))(png_ptr, struct_ptr); + return; + } +#endif /* PNG_USER_MEM_SUPPORTED */ +#if defined(__TURBOC__) && !defined(__FLAT__) + farfree(struct_ptr); +#else +# if defined(_MSC_VER) && defined(MAXSEG_64K) + hfree(struct_ptr); +# else + free(struct_ptr); +# endif +#endif + } +} + +/* Allocate memory. For reasonable files, size should never exceed + * 64K. However, zlib may allocate more then 64K if you don't tell + * it not to. See zconf.h and png.h for more information. zlib does + * need to allocate exactly 64K, so whatever you call here must + * have the ability to do that. + */ + +png_voidp PNGAPI +png_calloc(png_structp png_ptr, png_alloc_size_t size) +{ + png_voidp ret; + + ret = (png_malloc(png_ptr, size)); + if (ret != NULL) + png_memset(ret,0,(png_size_t)size); + return (ret); +} + +png_voidp PNGAPI +png_malloc(png_structp png_ptr, png_alloc_size_t size) +{ + png_voidp ret; + +#ifdef PNG_USER_MEM_SUPPORTED + if (png_ptr == NULL || size == 0) + return (NULL); + + if (png_ptr->malloc_fn != NULL) + ret = ((png_voidp)(*(png_ptr->malloc_fn))(png_ptr, (png_size_t)size)); + else + ret = (png_malloc_default(png_ptr, size)); + if (ret == NULL && (png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0) + png_error(png_ptr, "Out of Memory"); + return (ret); +} + +png_voidp PNGAPI +png_malloc_default(png_structp png_ptr, png_alloc_size_t size) +{ + png_voidp ret; +#endif /* PNG_USER_MEM_SUPPORTED */ + + if (png_ptr == NULL || size == 0) + return (NULL); + +#ifdef PNG_MAX_MALLOC_64K + if (size > (png_uint_32)65536L) + { +#ifndef PNG_USER_MEM_SUPPORTED + if ((png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0) + png_error(png_ptr, "Cannot Allocate > 64K"); + else +#endif + return NULL; + } +#endif + + /* Check for overflow */ +#if defined(__TURBOC__) && !defined(__FLAT__) + if (size != (unsigned long)size) + ret = NULL; + else + ret = farmalloc(size); +#else +# if defined(_MSC_VER) && defined(MAXSEG_64K) + if (size != (unsigned long)size) + ret = NULL; + else + ret = halloc(size, 1); +# else + if (size != (size_t)size) + ret = NULL; + else + ret = malloc((size_t)size); +# endif +#endif + +#ifndef PNG_USER_MEM_SUPPORTED + if (ret == NULL && (png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0) + png_error(png_ptr, "Out of Memory"); +#endif + + return (ret); +} + +/* Free a pointer allocated by png_malloc(). If ptr is NULL, return + * without taking any action. + */ +void PNGAPI +png_free(png_structp png_ptr, png_voidp ptr) +{ + if (png_ptr == NULL || ptr == NULL) + return; + +#ifdef PNG_USER_MEM_SUPPORTED + if (png_ptr->free_fn != NULL) + { + (*(png_ptr->free_fn))(png_ptr, ptr); + return; + } + else + png_free_default(png_ptr, ptr); +} +void PNGAPI +png_free_default(png_structp png_ptr, png_voidp ptr) +{ + if (png_ptr == NULL || ptr == NULL) + return; + +#endif /* PNG_USER_MEM_SUPPORTED */ + +#if defined(__TURBOC__) && !defined(__FLAT__) + farfree(ptr); +#else +# if defined(_MSC_VER) && defined(MAXSEG_64K) + hfree(ptr); +# else + free(ptr); +# endif +#endif +} + +#endif /* Not Borland DOS special memory handler */ + +/* This function was added at libpng version 1.2.3. The png_malloc_warn() + * function will set up png_malloc() to issue a png_warning and return NULL + * instead of issuing a png_error, if it fails to allocate the requested + * memory. + */ +png_voidp PNGAPI +png_malloc_warn(png_structp png_ptr, png_alloc_size_t size) +{ + png_voidp ptr; + png_uint_32 save_flags; + if (png_ptr == NULL) + return (NULL); + + save_flags = png_ptr->flags; + png_ptr->flags|=PNG_FLAG_MALLOC_NULL_MEM_OK; + ptr = (png_voidp)png_malloc((png_structp)png_ptr, size); + png_ptr->flags=save_flags; + return(ptr); +} + + +#ifdef PNG_USER_MEM_SUPPORTED +/* This function is called when the application wants to use another method + * of allocating and freeing memory. + */ +void PNGAPI +png_set_mem_fn(png_structp png_ptr, png_voidp mem_ptr, png_malloc_ptr + malloc_fn, png_free_ptr free_fn) +{ + if (png_ptr != NULL) + { + png_ptr->mem_ptr = mem_ptr; + png_ptr->malloc_fn = malloc_fn; + png_ptr->free_fn = free_fn; + } +} + +/* This function returns a pointer to the mem_ptr associated with the user + * functions. The application should free any memory associated with this + * pointer before png_write_destroy and png_read_destroy are called. + */ +png_voidp PNGAPI +png_get_mem_ptr(png_structp png_ptr) +{ + if (png_ptr == NULL) + return (NULL); + return ((png_voidp)png_ptr->mem_ptr); +} +#endif /* PNG_USER_MEM_SUPPORTED */ +#endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */ diff --git a/libpng/pngpread.c b/libpng/pngpread.c new file mode 100644 index 0000000..e33b428 --- /dev/null +++ b/libpng/pngpread.c @@ -0,0 +1,1765 @@ + +/* pngpread.c - read a png file in push mode + * + * Last changed in libpng 1.4.3 [June 26, 2010] + * Copyright (c) 1998-2010 Glenn Randers-Pehrson + * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) + * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) + * + * This code is released under the libpng license. + * For conditions of distribution and use, see the disclaimer + * and license in png.h + */ + +#define PNG_NO_PEDANTIC_WARNINGS +#include "png.h" +#ifdef PNG_PROGRESSIVE_READ_SUPPORTED +#include "pngpriv.h" + +/* Push model modes */ +#define PNG_READ_SIG_MODE 0 +#define PNG_READ_CHUNK_MODE 1 +#define PNG_READ_IDAT_MODE 2 +#define PNG_SKIP_MODE 3 +#define PNG_READ_tEXt_MODE 4 +#define PNG_READ_zTXt_MODE 5 +#define PNG_READ_DONE_MODE 6 +#define PNG_READ_iTXt_MODE 7 +#define PNG_ERROR_MODE 8 + +void PNGAPI +png_process_data(png_structp png_ptr, png_infop info_ptr, + png_bytep buffer, png_size_t buffer_size) +{ + if (png_ptr == NULL || info_ptr == NULL) + return; + + png_push_restore_buffer(png_ptr, buffer, buffer_size); + + while (png_ptr->buffer_size) + { + png_process_some_data(png_ptr, info_ptr); + } +} + +/* What we do with the incoming data depends on what we were previously + * doing before we ran out of data... + */ +void /* PRIVATE */ +png_process_some_data(png_structp png_ptr, png_infop info_ptr) +{ + if (png_ptr == NULL) + return; + + switch (png_ptr->process_mode) + { + case PNG_READ_SIG_MODE: + { + png_push_read_sig(png_ptr, info_ptr); + break; + } + + case PNG_READ_CHUNK_MODE: + { + png_push_read_chunk(png_ptr, info_ptr); + break; + } + + case PNG_READ_IDAT_MODE: + { + png_push_read_IDAT(png_ptr); + break; + } + +#ifdef PNG_READ_tEXt_SUPPORTED + case PNG_READ_tEXt_MODE: + { + png_push_read_tEXt(png_ptr, info_ptr); + break; + } + +#endif +#ifdef PNG_READ_zTXt_SUPPORTED + case PNG_READ_zTXt_MODE: + { + png_push_read_zTXt(png_ptr, info_ptr); + break; + } + +#endif +#ifdef PNG_READ_iTXt_SUPPORTED + case PNG_READ_iTXt_MODE: + { + png_push_read_iTXt(png_ptr, info_ptr); + break; + } + +#endif + case PNG_SKIP_MODE: + { + png_push_crc_finish(png_ptr); + break; + } + + default: + { + png_ptr->buffer_size = 0; + break; + } + } +} + +/* Read any remaining signature bytes from the stream and compare them with + * the correct PNG signature. It is possible that this routine is called + * with bytes already read from the signature, either because they have been + * checked by the calling application, or because of multiple calls to this + * routine. + */ +void /* PRIVATE */ +png_push_read_sig(png_structp png_ptr, png_infop info_ptr) +{ + png_size_t num_checked = png_ptr->sig_bytes, + num_to_check = 8 - num_checked; + + if (png_ptr->buffer_size < num_to_check) + { + num_to_check = png_ptr->buffer_size; + } + + png_push_fill_buffer(png_ptr, &(info_ptr->signature[num_checked]), + num_to_check); + png_ptr->sig_bytes = (png_byte)(png_ptr->sig_bytes + num_to_check); + + if (png_sig_cmp(info_ptr->signature, num_checked, num_to_check)) + { + if (num_checked < 4 && + png_sig_cmp(info_ptr->signature, num_checked, num_to_check - 4)) + png_error(png_ptr, "Not a PNG file"); + else + png_error(png_ptr, "PNG file corrupted by ASCII conversion"); + } + else + { + if (png_ptr->sig_bytes >= 8) + { + png_ptr->process_mode = PNG_READ_CHUNK_MODE; + } + } +} + +void /* PRIVATE */ +png_push_read_chunk(png_structp png_ptr, png_infop info_ptr) +{ + PNG_IHDR; + PNG_IDAT; + PNG_IEND; + PNG_PLTE; +#ifdef PNG_READ_bKGD_SUPPORTED + PNG_bKGD; +#endif +#ifdef PNG_READ_cHRM_SUPPORTED + PNG_cHRM; +#endif +#ifdef PNG_READ_gAMA_SUPPORTED + PNG_gAMA; +#endif +#ifdef PNG_READ_hIST_SUPPORTED + PNG_hIST; +#endif +#ifdef PNG_READ_iCCP_SUPPORTED + PNG_iCCP; +#endif +#ifdef PNG_READ_iTXt_SUPPORTED + PNG_iTXt; +#endif +#ifdef PNG_READ_oFFs_SUPPORTED + PNG_oFFs; +#endif +#ifdef PNG_READ_pCAL_SUPPORTED + PNG_pCAL; +#endif +#ifdef PNG_READ_pHYs_SUPPORTED + PNG_pHYs; +#endif +#ifdef PNG_READ_sBIT_SUPPORTED + PNG_sBIT; +#endif +#ifdef PNG_READ_sCAL_SUPPORTED + PNG_sCAL; +#endif +#ifdef PNG_READ_sRGB_SUPPORTED + PNG_sRGB; +#endif +#ifdef PNG_READ_sPLT_SUPPORTED + PNG_sPLT; +#endif +#ifdef PNG_READ_tEXt_SUPPORTED + PNG_tEXt; +#endif +#ifdef PNG_READ_tIME_SUPPORTED + PNG_tIME; +#endif +#ifdef PNG_READ_tRNS_SUPPORTED + PNG_tRNS; +#endif +#ifdef PNG_READ_zTXt_SUPPORTED + PNG_zTXt; +#endif + + /* First we make sure we have enough data for the 4 byte chunk name + * and the 4 byte chunk length before proceeding with decoding the + * chunk data. To fully decode each of these chunks, we also make + * sure we have enough data in the buffer for the 4 byte CRC at the + * end of every chunk (except IDAT, which is handled separately). + */ + if (!(png_ptr->mode & PNG_HAVE_CHUNK_HEADER)) + { + png_byte chunk_length[4]; + + if (png_ptr->buffer_size < 8) + { + png_push_save_buffer(png_ptr); + return; + } + + png_push_fill_buffer(png_ptr, chunk_length, 4); + png_ptr->push_length = png_get_uint_31(png_ptr, chunk_length); + png_reset_crc(png_ptr); + png_crc_read(png_ptr, png_ptr->chunk_name, 4); + png_check_chunk_name(png_ptr, png_ptr->chunk_name); + png_ptr->mode |= PNG_HAVE_CHUNK_HEADER; + } + + if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) + if (png_ptr->mode & PNG_AFTER_IDAT) + png_ptr->mode |= PNG_HAVE_CHUNK_AFTER_IDAT; + + if (!png_memcmp(png_ptr->chunk_name, png_IHDR, 4)) + { + if (png_ptr->push_length != 13) + png_error(png_ptr, "Invalid IHDR length"); + + if (png_ptr->push_length + 4 > png_ptr->buffer_size) + { + png_push_save_buffer(png_ptr); + return; + } + + png_handle_IHDR(png_ptr, info_ptr, png_ptr->push_length); + } + + else if (!png_memcmp(png_ptr->chunk_name, png_IEND, 4)) + { + if (png_ptr->push_length + 4 > png_ptr->buffer_size) + { + png_push_save_buffer(png_ptr); + return; + } + + png_handle_IEND(png_ptr, info_ptr, png_ptr->push_length); + + png_ptr->process_mode = PNG_READ_DONE_MODE; + png_push_have_end(png_ptr, info_ptr); + } + +#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED + else if (png_handle_as_unknown(png_ptr, png_ptr->chunk_name)) + { + if (png_ptr->push_length + 4 > png_ptr->buffer_size) + { + png_push_save_buffer(png_ptr); + return; + } + + if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) + png_ptr->mode |= PNG_HAVE_IDAT; + + png_handle_unknown(png_ptr, info_ptr, png_ptr->push_length); + + if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4)) + png_ptr->mode |= PNG_HAVE_PLTE; + + else if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) + { + if (!(png_ptr->mode & PNG_HAVE_IHDR)) + png_error(png_ptr, "Missing IHDR before IDAT"); + + else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE && + !(png_ptr->mode & PNG_HAVE_PLTE)) + png_error(png_ptr, "Missing PLTE before IDAT"); + } + } + +#endif + else if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4)) + { + if (png_ptr->push_length + 4 > png_ptr->buffer_size) + { + png_push_save_buffer(png_ptr); + return; + } + png_handle_PLTE(png_ptr, info_ptr, png_ptr->push_length); + } + + else if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) + { + /* If we reach an IDAT chunk, this means we have read all of the + * header chunks, and we can start reading the image (or if this + * is called after the image has been read - we have an error). + */ + + if (!(png_ptr->mode & PNG_HAVE_IHDR)) + png_error(png_ptr, "Missing IHDR before IDAT"); + + else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE && + !(png_ptr->mode & PNG_HAVE_PLTE)) + png_error(png_ptr, "Missing PLTE before IDAT"); + + if (png_ptr->mode & PNG_HAVE_IDAT) + { + if (!(png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT)) + if (png_ptr->push_length == 0) + return; + + if (png_ptr->mode & PNG_AFTER_IDAT) + png_benign_error(png_ptr, "Too many IDATs found"); + } + + png_ptr->idat_size = png_ptr->push_length; + png_ptr->mode |= PNG_HAVE_IDAT; + png_ptr->process_mode = PNG_READ_IDAT_MODE; + png_push_have_info(png_ptr, info_ptr); + png_ptr->zstream.avail_out = + (uInt) PNG_ROWBYTES(png_ptr->pixel_depth, + png_ptr->iwidth) + 1; + png_ptr->zstream.next_out = png_ptr->row_buf; + return; + } + +#ifdef PNG_READ_gAMA_SUPPORTED + else if (!png_memcmp(png_ptr->chunk_name, png_gAMA, 4)) + { + if (png_ptr->push_length + 4 > png_ptr->buffer_size) + { + png_push_save_buffer(png_ptr); + return; + } + + png_handle_gAMA(png_ptr, info_ptr, png_ptr->push_length); + } + +#endif +#ifdef PNG_READ_sBIT_SUPPORTED + else if (!png_memcmp(png_ptr->chunk_name, png_sBIT, 4)) + { + if (png_ptr->push_length + 4 > png_ptr->buffer_size) + { + png_push_save_buffer(png_ptr); + return; + } + + png_handle_sBIT(png_ptr, info_ptr, png_ptr->push_length); + } + +#endif +#ifdef PNG_READ_cHRM_SUPPORTED + else if (!png_memcmp(png_ptr->chunk_name, png_cHRM, 4)) + { + if (png_ptr->push_length + 4 > png_ptr->buffer_size) + { + png_push_save_buffer(png_ptr); + return; + } + + png_handle_cHRM(png_ptr, info_ptr, png_ptr->push_length); + } + +#endif +#ifdef PNG_READ_sRGB_SUPPORTED + else if (!png_memcmp(png_ptr->chunk_name, png_sRGB, 4)) + { + if (png_ptr->push_length + 4 > png_ptr->buffer_size) + { + png_push_save_buffer(png_ptr); + return; + } + + png_handle_sRGB(png_ptr, info_ptr, png_ptr->push_length); + } + +#endif +#ifdef PNG_READ_iCCP_SUPPORTED + else if (!png_memcmp(png_ptr->chunk_name, png_iCCP, 4)) + { + if (png_ptr->push_length + 4 > png_ptr->buffer_size) + { + png_push_save_buffer(png_ptr); + return; + } + + png_handle_iCCP(png_ptr, info_ptr, png_ptr->push_length); + } + +#endif +#ifdef PNG_READ_sPLT_SUPPORTED + else if (!png_memcmp(png_ptr->chunk_name, png_sPLT, 4)) + { + if (png_ptr->push_length + 4 > png_ptr->buffer_size) + { + png_push_save_buffer(png_ptr); + return; + } + + png_handle_sPLT(png_ptr, info_ptr, png_ptr->push_length); + } + +#endif +#ifdef PNG_READ_tRNS_SUPPORTED + else if (!png_memcmp(png_ptr->chunk_name, png_tRNS, 4)) + { + if (png_ptr->push_length + 4 > png_ptr->buffer_size) + { + png_push_save_buffer(png_ptr); + return; + } + + png_handle_tRNS(png_ptr, info_ptr, png_ptr->push_length); + } + +#endif +#ifdef PNG_READ_bKGD_SUPPORTED + else if (!png_memcmp(png_ptr->chunk_name, png_bKGD, 4)) + { + if (png_ptr->push_length + 4 > png_ptr->buffer_size) + { + png_push_save_buffer(png_ptr); + return; + } + + png_handle_bKGD(png_ptr, info_ptr, png_ptr->push_length); + } + +#endif +#ifdef PNG_READ_hIST_SUPPORTED + else if (!png_memcmp(png_ptr->chunk_name, png_hIST, 4)) + { + if (png_ptr->push_length + 4 > png_ptr->buffer_size) + { + png_push_save_buffer(png_ptr); + return; + } + + png_handle_hIST(png_ptr, info_ptr, png_ptr->push_length); + } + +#endif +#ifdef PNG_READ_pHYs_SUPPORTED + else if (!png_memcmp(png_ptr->chunk_name, png_pHYs, 4)) + { + if (png_ptr->push_length + 4 > png_ptr->buffer_size) + { + png_push_save_buffer(png_ptr); + return; + } + + png_handle_pHYs(png_ptr, info_ptr, png_ptr->push_length); + } + +#endif +#ifdef PNG_READ_oFFs_SUPPORTED + else if (!png_memcmp(png_ptr->chunk_name, png_oFFs, 4)) + { + if (png_ptr->push_length + 4 > png_ptr->buffer_size) + { + png_push_save_buffer(png_ptr); + return; + } + + png_handle_oFFs(png_ptr, info_ptr, png_ptr->push_length); + } +#endif + +#ifdef PNG_READ_pCAL_SUPPORTED + else if (!png_memcmp(png_ptr->chunk_name, png_pCAL, 4)) + { + if (png_ptr->push_length + 4 > png_ptr->buffer_size) + { + png_push_save_buffer(png_ptr); + return; + } + + png_handle_pCAL(png_ptr, info_ptr, png_ptr->push_length); + } + +#endif +#ifdef PNG_READ_sCAL_SUPPORTED + else if (!png_memcmp(png_ptr->chunk_name, png_sCAL, 4)) + { + if (png_ptr->push_length + 4 > png_ptr->buffer_size) + { + png_push_save_buffer(png_ptr); + return; + } + + png_handle_sCAL(png_ptr, info_ptr, png_ptr->push_length); + } + +#endif +#ifdef PNG_READ_tIME_SUPPORTED + else if (!png_memcmp(png_ptr->chunk_name, png_tIME, 4)) + { + if (png_ptr->push_length + 4 > png_ptr->buffer_size) + { + png_push_save_buffer(png_ptr); + return; + } + + png_handle_tIME(png_ptr, info_ptr, png_ptr->push_length); + } + +#endif +#ifdef PNG_READ_tEXt_SUPPORTED + else if (!png_memcmp(png_ptr->chunk_name, png_tEXt, 4)) + { + if (png_ptr->push_length + 4 > png_ptr->buffer_size) + { + png_push_save_buffer(png_ptr); + return; + } + + png_push_handle_tEXt(png_ptr, info_ptr, png_ptr->push_length); + } + +#endif +#ifdef PNG_READ_zTXt_SUPPORTED + else if (!png_memcmp(png_ptr->chunk_name, png_zTXt, 4)) + { + if (png_ptr->push_length + 4 > png_ptr->buffer_size) + { + png_push_save_buffer(png_ptr); + return; + } + + png_push_handle_zTXt(png_ptr, info_ptr, png_ptr->push_length); + } + +#endif +#ifdef PNG_READ_iTXt_SUPPORTED + else if (!png_memcmp(png_ptr->chunk_name, png_iTXt, 4)) + { + if (png_ptr->push_length + 4 > png_ptr->buffer_size) + { + png_push_save_buffer(png_ptr); + return; + } + + png_push_handle_iTXt(png_ptr, info_ptr, png_ptr->push_length); + } + +#endif + else + { + if (png_ptr->push_length + 4 > png_ptr->buffer_size) + { + png_push_save_buffer(png_ptr); + return; + } + png_push_handle_unknown(png_ptr, info_ptr, png_ptr->push_length); + } + + png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER; +} + +void /* PRIVATE */ +png_push_crc_skip(png_structp png_ptr, png_uint_32 skip) +{ + png_ptr->process_mode = PNG_SKIP_MODE; + png_ptr->skip_length = skip; +} + +void /* PRIVATE */ +png_push_crc_finish(png_structp png_ptr) +{ + if (png_ptr->skip_length && png_ptr->save_buffer_size) + { + png_size_t save_size; + + if (png_ptr->skip_length < (png_uint_32)png_ptr->save_buffer_size) + save_size = (png_size_t)png_ptr->skip_length; + else + save_size = png_ptr->save_buffer_size; + + png_calculate_crc(png_ptr, png_ptr->save_buffer_ptr, save_size); + + png_ptr->skip_length -= save_size; + png_ptr->buffer_size -= save_size; + png_ptr->save_buffer_size -= save_size; + png_ptr->save_buffer_ptr += save_size; + } + if (png_ptr->skip_length && png_ptr->current_buffer_size) + { + png_size_t save_size; + + if (png_ptr->skip_length < (png_uint_32)png_ptr->current_buffer_size) + save_size = (png_size_t)png_ptr->skip_length; + else + save_size = png_ptr->current_buffer_size; + + png_calculate_crc(png_ptr, png_ptr->current_buffer_ptr, save_size); + + png_ptr->skip_length -= save_size; + png_ptr->buffer_size -= save_size; + png_ptr->current_buffer_size -= save_size; + png_ptr->current_buffer_ptr += save_size; + } + if (!png_ptr->skip_length) + { + if (png_ptr->buffer_size < 4) + { + png_push_save_buffer(png_ptr); + return; + } + + png_crc_finish(png_ptr, 0); + png_ptr->process_mode = PNG_READ_CHUNK_MODE; + } +} + +void PNGAPI +png_push_fill_buffer(png_structp png_ptr, png_bytep buffer, png_size_t length) +{ + png_bytep ptr; + + if (png_ptr == NULL) + return; + + ptr = buffer; + if (png_ptr->save_buffer_size) + { + png_size_t save_size; + + if (length < png_ptr->save_buffer_size) + save_size = length; + else + save_size = png_ptr->save_buffer_size; + + png_memcpy(ptr, png_ptr->save_buffer_ptr, save_size); + length -= save_size; + ptr += save_size; + png_ptr->buffer_size -= save_size; + png_ptr->save_buffer_size -= save_size; + png_ptr->save_buffer_ptr += save_size; + } + if (length && png_ptr->current_buffer_size) + { + png_size_t save_size; + + if (length < png_ptr->current_buffer_size) + save_size = length; + + else + save_size = png_ptr->current_buffer_size; + + png_memcpy(ptr, png_ptr->current_buffer_ptr, save_size); + png_ptr->buffer_size -= save_size; + png_ptr->current_buffer_size -= save_size; + png_ptr->current_buffer_ptr += save_size; + } +} + +void /* PRIVATE */ +png_push_save_buffer(png_structp png_ptr) +{ + if (png_ptr->save_buffer_size) + { + if (png_ptr->save_buffer_ptr != png_ptr->save_buffer) + { + png_size_t i, istop; + png_bytep sp; + png_bytep dp; + + istop = png_ptr->save_buffer_size; + for (i = 0, sp = png_ptr->save_buffer_ptr, dp = png_ptr->save_buffer; + i < istop; i++, sp++, dp++) + { + *dp = *sp; + } + } + } + if (png_ptr->save_buffer_size + png_ptr->current_buffer_size > + png_ptr->save_buffer_max) + { + png_size_t new_max; + png_bytep old_buffer; + + if (png_ptr->save_buffer_size > PNG_SIZE_MAX - + (png_ptr->current_buffer_size + 256)) + { + png_error(png_ptr, "Potential overflow of save_buffer"); + } + + new_max = png_ptr->save_buffer_size + png_ptr->current_buffer_size + 256; + old_buffer = png_ptr->save_buffer; + png_ptr->save_buffer = (png_bytep)png_malloc_warn(png_ptr, + (png_size_t)new_max); + if (png_ptr->save_buffer == NULL) + { + png_free(png_ptr, old_buffer); + png_error(png_ptr, "Insufficient memory for save_buffer"); + } + png_memcpy(png_ptr->save_buffer, old_buffer, png_ptr->save_buffer_size); + png_free(png_ptr, old_buffer); + png_ptr->save_buffer_max = new_max; + } + if (png_ptr->current_buffer_size) + { + png_memcpy(png_ptr->save_buffer + png_ptr->save_buffer_size, + png_ptr->current_buffer_ptr, png_ptr->current_buffer_size); + png_ptr->save_buffer_size += png_ptr->current_buffer_size; + png_ptr->current_buffer_size = 0; + } + png_ptr->save_buffer_ptr = png_ptr->save_buffer; + png_ptr->buffer_size = 0; +} + +void /* PRIVATE */ +png_push_restore_buffer(png_structp png_ptr, png_bytep buffer, + png_size_t buffer_length) +{ + png_ptr->current_buffer = buffer; + png_ptr->current_buffer_size = buffer_length; + png_ptr->buffer_size = buffer_length + png_ptr->save_buffer_size; + png_ptr->current_buffer_ptr = png_ptr->current_buffer; +} + +void /* PRIVATE */ +png_push_read_IDAT(png_structp png_ptr) +{ + PNG_IDAT; + if (!(png_ptr->mode & PNG_HAVE_CHUNK_HEADER)) + { + png_byte chunk_length[4]; + + if (png_ptr->buffer_size < 8) + { + png_push_save_buffer(png_ptr); + return; + } + + png_push_fill_buffer(png_ptr, chunk_length, 4); + png_ptr->push_length = png_get_uint_31(png_ptr, chunk_length); + png_reset_crc(png_ptr); + png_crc_read(png_ptr, png_ptr->chunk_name, 4); + png_ptr->mode |= PNG_HAVE_CHUNK_HEADER; + + if (png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) + { + png_ptr->process_mode = PNG_READ_CHUNK_MODE; + if (!(png_ptr->flags & PNG_FLAG_ZLIB_FINISHED)) + png_error(png_ptr, "Not enough compressed data"); + return; + } + + png_ptr->idat_size = png_ptr->push_length; + } + if (png_ptr->idat_size && png_ptr->save_buffer_size) + { + png_size_t save_size; + + if (png_ptr->idat_size < (png_uint_32)png_ptr->save_buffer_size) + { + save_size = (png_size_t)png_ptr->idat_size; + + /* Check for overflow */ + if ((png_uint_32)save_size != png_ptr->idat_size) + png_error(png_ptr, "save_size overflowed in pngpread"); + } + else + save_size = png_ptr->save_buffer_size; + + png_calculate_crc(png_ptr, png_ptr->save_buffer_ptr, save_size); + + png_process_IDAT_data(png_ptr, png_ptr->save_buffer_ptr, save_size); + + png_ptr->idat_size -= save_size; + png_ptr->buffer_size -= save_size; + png_ptr->save_buffer_size -= save_size; + png_ptr->save_buffer_ptr += save_size; + } + if (png_ptr->idat_size && png_ptr->current_buffer_size) + { + png_size_t save_size; + + if (png_ptr->idat_size < (png_uint_32)png_ptr->current_buffer_size) + { + save_size = (png_size_t)png_ptr->idat_size; + + /* Check for overflow */ + if ((png_uint_32)save_size != png_ptr->idat_size) + png_error(png_ptr, "save_size overflowed in pngpread"); + } + else + save_size = png_ptr->current_buffer_size; + + png_calculate_crc(png_ptr, png_ptr->current_buffer_ptr, save_size); + + png_process_IDAT_data(png_ptr, png_ptr->current_buffer_ptr, save_size); + + png_ptr->idat_size -= save_size; + png_ptr->buffer_size -= save_size; + png_ptr->current_buffer_size -= save_size; + png_ptr->current_buffer_ptr += save_size; + } + if (!png_ptr->idat_size) + { + if (png_ptr->buffer_size < 4) + { + png_push_save_buffer(png_ptr); + return; + } + + png_crc_finish(png_ptr, 0); + png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER; + png_ptr->mode |= PNG_AFTER_IDAT; + } +} + +void /* PRIVATE */ +png_process_IDAT_data(png_structp png_ptr, png_bytep buffer, + png_size_t buffer_length) +{ + /* The caller checks for a non-zero buffer length. */ + if (!(buffer_length > 0) || buffer == NULL) + png_error(png_ptr, "No IDAT data (internal error)"); + + /* This routine must process all the data it has been given + * before returning, calling the row callback as required to + * handle the uncompressed results. + */ + png_ptr->zstream.next_in = buffer; + png_ptr->zstream.avail_in = (uInt)buffer_length; + + /* Keep going until the decompressed data is all processed + * or the stream marked as finished. + */ + while (png_ptr->zstream.avail_in > 0 && + !(png_ptr->flags & PNG_FLAG_ZLIB_FINISHED)) + { + int ret; + + /* We have data for zlib, but we must check that zlib + * has somewhere to put the results. It doesn't matter + * if we don't expect any results -- it may be the input + * data is just the LZ end code. + */ + if (!(png_ptr->zstream.avail_out > 0)) + { + png_ptr->zstream.avail_out = + (uInt) PNG_ROWBYTES(png_ptr->pixel_depth, + png_ptr->iwidth) + 1; + png_ptr->zstream.next_out = png_ptr->row_buf; + } + + /* Using Z_SYNC_FLUSH here means that an unterminated + * LZ stream can still be handled (a stream with a missing + * end code), otherwise (Z_NO_FLUSH) a future zlib + * implementation might defer output and, therefore, + * change the current behavior. (See comments in inflate.c + * for why this doesn't happen at present with zlib 1.2.5.) + */ + ret = inflate(&png_ptr->zstream, Z_SYNC_FLUSH); + + /* Check for any failure before proceeding. */ + if (ret != Z_OK && ret != Z_STREAM_END) + { + /* Terminate the decompression. */ + png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED; + + /* This may be a truncated stream (missing or + * damaged end code). Treat that as a warning. + */ + if (png_ptr->row_number >= png_ptr->num_rows || + png_ptr->pass > 6) + png_warning(png_ptr, "Truncated compressed data in IDAT"); + else + png_error(png_ptr, "Decompression error in IDAT"); + + /* Skip the check on unprocessed input */ + return; + } + + /* Did inflate output any data? */ + if (png_ptr->zstream.next_out != png_ptr->row_buf) + { + /* Is this unexpected data after the last row? + * If it is, artificially terminate the LZ output + * here. + */ + if (png_ptr->row_number >= png_ptr->num_rows || + png_ptr->pass > 6) + { + /* Extra data. */ + png_warning(png_ptr, "Extra compressed data in IDAT"); + png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED; + /* Do no more processing; skip the unprocessed + * input check below. + */ + return; + } + + /* Do we have a complete row? */ + if (png_ptr->zstream.avail_out == 0) + png_push_process_row(png_ptr); + } + + /* And check for the end of the stream. */ + if (ret == Z_STREAM_END) + png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED; + } + + /* All the data should have been processed, if anything + * is left at this point we have bytes of IDAT data + * after the zlib end code. + */ + if (png_ptr->zstream.avail_in > 0) + png_warning(png_ptr, "Extra compression data"); +} + +void /* PRIVATE */ +png_push_process_row(png_structp png_ptr) +{ + png_ptr->row_info.color_type = png_ptr->color_type; + png_ptr->row_info.width = png_ptr->iwidth; + png_ptr->row_info.channels = png_ptr->channels; + png_ptr->row_info.bit_depth = png_ptr->bit_depth; + png_ptr->row_info.pixel_depth = png_ptr->pixel_depth; + + png_ptr->row_info.rowbytes = PNG_ROWBYTES(png_ptr->row_info.pixel_depth, + png_ptr->row_info.width); + + png_read_filter_row(png_ptr, &(png_ptr->row_info), + png_ptr->row_buf + 1, png_ptr->prev_row + 1, + (int)(png_ptr->row_buf[0])); + + png_memcpy(png_ptr->prev_row, png_ptr->row_buf, png_ptr->rowbytes + 1); + + if (png_ptr->transformations || (png_ptr->flags&PNG_FLAG_STRIP_ALPHA)) + png_do_read_transformations(png_ptr); + +#ifdef PNG_READ_INTERLACING_SUPPORTED + /* Blow up interlaced rows to full size */ + if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE)) + { + if (png_ptr->pass < 6) +/* old interface (pre-1.0.9): + png_do_read_interlace(&(png_ptr->row_info), + png_ptr->row_buf + 1, png_ptr->pass, png_ptr->transformations); + */ + png_do_read_interlace(png_ptr); + + switch (png_ptr->pass) + { + case 0: + { + int i; + for (i = 0; i < 8 && png_ptr->pass == 0; i++) + { + png_push_have_row(png_ptr, png_ptr->row_buf + 1); + png_read_push_finish_row(png_ptr); /* Updates png_ptr->pass */ + } + + if (png_ptr->pass == 2) /* Pass 1 might be empty */ + { + for (i = 0; i < 4 && png_ptr->pass == 2; i++) + { + png_push_have_row(png_ptr, NULL); + png_read_push_finish_row(png_ptr); + } + } + + if (png_ptr->pass == 4 && png_ptr->height <= 4) + { + for (i = 0; i < 2 && png_ptr->pass == 4; i++) + { + png_push_have_row(png_ptr, NULL); + png_read_push_finish_row(png_ptr); + } + } + + if (png_ptr->pass == 6 && png_ptr->height <= 4) + { + png_push_have_row(png_ptr, NULL); + png_read_push_finish_row(png_ptr); + } + + break; + } + + case 1: + { + int i; + for (i = 0; i < 8 && png_ptr->pass == 1; i++) + { + png_push_have_row(png_ptr, png_ptr->row_buf + 1); + png_read_push_finish_row(png_ptr); + } + + if (png_ptr->pass == 2) /* Skip top 4 generated rows */ + { + for (i = 0; i < 4 && png_ptr->pass == 2; i++) + { + png_push_have_row(png_ptr, NULL); + png_read_push_finish_row(png_ptr); + } + } + + break; + } + + case 2: + { + int i; + + for (i = 0; i < 4 && png_ptr->pass == 2; i++) + { + png_push_have_row(png_ptr, png_ptr->row_buf + 1); + png_read_push_finish_row(png_ptr); + } + + for (i = 0; i < 4 && png_ptr->pass == 2; i++) + { + png_push_have_row(png_ptr, NULL); + png_read_push_finish_row(png_ptr); + } + + if (png_ptr->pass == 4) /* Pass 3 might be empty */ + { + for (i = 0; i < 2 && png_ptr->pass == 4; i++) + { + png_push_have_row(png_ptr, NULL); + png_read_push_finish_row(png_ptr); + } + } + + break; + } + + case 3: + { + int i; + + for (i = 0; i < 4 && png_ptr->pass == 3; i++) + { + png_push_have_row(png_ptr, png_ptr->row_buf + 1); + png_read_push_finish_row(png_ptr); + } + + if (png_ptr->pass == 4) /* Skip top two generated rows */ + { + for (i = 0; i < 2 && png_ptr->pass == 4; i++) + { + png_push_have_row(png_ptr, NULL); + png_read_push_finish_row(png_ptr); + } + } + + break; + } + + case 4: + { + int i; + + for (i = 0; i < 2 && png_ptr->pass == 4; i++) + { + png_push_have_row(png_ptr, png_ptr->row_buf + 1); + png_read_push_finish_row(png_ptr); + } + + for (i = 0; i < 2 && png_ptr->pass == 4; i++) + { + png_push_have_row(png_ptr, NULL); + png_read_push_finish_row(png_ptr); + } + + if (png_ptr->pass == 6) /* Pass 5 might be empty */ + { + png_push_have_row(png_ptr, NULL); + png_read_push_finish_row(png_ptr); + } + + break; + } + + case 5: + { + int i; + + for (i = 0; i < 2 && png_ptr->pass == 5; i++) + { + png_push_have_row(png_ptr, png_ptr->row_buf + 1); + png_read_push_finish_row(png_ptr); + } + + if (png_ptr->pass == 6) /* Skip top generated row */ + { + png_push_have_row(png_ptr, NULL); + png_read_push_finish_row(png_ptr); + } + + break; + } + case 6: + { + png_push_have_row(png_ptr, png_ptr->row_buf + 1); + png_read_push_finish_row(png_ptr); + + if (png_ptr->pass != 6) + break; + + png_push_have_row(png_ptr, NULL); + png_read_push_finish_row(png_ptr); + } + } + } + else +#endif + { + png_push_have_row(png_ptr, png_ptr->row_buf + 1); + png_read_push_finish_row(png_ptr); + } +} + +void /* PRIVATE */ +png_read_push_finish_row(png_structp png_ptr) +{ + /* Arrays to facilitate easy interlacing - use pass (0 - 6) as index */ + + /* Start of interlace block */ + PNG_CONST int FARDATA png_pass_start[] = {0, 4, 0, 2, 0, 1, 0}; + + /* Offset to next interlace block */ + PNG_CONST int FARDATA png_pass_inc[] = {8, 8, 4, 4, 2, 2, 1}; + + /* Start of interlace block in the y direction */ + PNG_CONST int FARDATA png_pass_ystart[] = {0, 0, 4, 0, 2, 0, 1}; + + /* Offset to next interlace block in the y direction */ + PNG_CONST int FARDATA png_pass_yinc[] = {8, 8, 8, 4, 4, 2, 2}; + + /* Height of interlace block. This is not currently used - if you need + * it, uncomment it here and in png.h + PNG_CONST int FARDATA png_pass_height[] = {8, 8, 4, 4, 2, 2, 1}; + */ + + png_ptr->row_number++; + if (png_ptr->row_number < png_ptr->num_rows) + return; + +#ifdef PNG_READ_INTERLACING_SUPPORTED + if (png_ptr->interlaced) + { + png_ptr->row_number = 0; + png_memset(png_ptr->prev_row, 0, + png_ptr->rowbytes + 1); + do + { + png_ptr->pass++; + if ((png_ptr->pass == 1 && png_ptr->width < 5) || + (png_ptr->pass == 3 && png_ptr->width < 3) || + (png_ptr->pass == 5 && png_ptr->width < 2)) + png_ptr->pass++; + + if (png_ptr->pass > 7) + png_ptr->pass--; + + if (png_ptr->pass >= 7) + break; + + png_ptr->iwidth = (png_ptr->width + + png_pass_inc[png_ptr->pass] - 1 - + png_pass_start[png_ptr->pass]) / + png_pass_inc[png_ptr->pass]; + + if (png_ptr->transformations & PNG_INTERLACE) + break; + + png_ptr->num_rows = (png_ptr->height + + png_pass_yinc[png_ptr->pass] - 1 - + png_pass_ystart[png_ptr->pass]) / + png_pass_yinc[png_ptr->pass]; + + } while (png_ptr->iwidth == 0 || png_ptr->num_rows == 0); + } +#endif /* PNG_READ_INTERLACING_SUPPORTED */ +} + +#ifdef PNG_READ_tEXt_SUPPORTED +void /* PRIVATE */ +png_push_handle_tEXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 + length) +{ + if (!(png_ptr->mode & PNG_HAVE_IHDR) || (png_ptr->mode & PNG_HAVE_IEND)) + { + png_error(png_ptr, "Out of place tEXt"); + info_ptr = info_ptr; /* To quiet some compiler warnings */ + } + +#ifdef PNG_MAX_MALLOC_64K + png_ptr->skip_length = 0; /* This may not be necessary */ + + if (length > (png_uint_32)65535L) /* Can't hold entire string in memory */ + { + png_warning(png_ptr, "tEXt chunk too large to fit in memory"); + png_ptr->skip_length = length - (png_uint_32)65535L; + length = (png_uint_32)65535L; + } +#endif + + png_ptr->current_text = (png_charp)png_malloc(png_ptr, + (png_size_t)(length + 1)); + png_ptr->current_text[length] = '\0'; + png_ptr->current_text_ptr = png_ptr->current_text; + png_ptr->current_text_size = (png_size_t)length; + png_ptr->current_text_left = (png_size_t)length; + png_ptr->process_mode = PNG_READ_tEXt_MODE; +} + +void /* PRIVATE */ +png_push_read_tEXt(png_structp png_ptr, png_infop info_ptr) +{ + if (png_ptr->buffer_size && png_ptr->current_text_left) + { + png_size_t text_size; + + if (png_ptr->buffer_size < png_ptr->current_text_left) + text_size = png_ptr->buffer_size; + + else + text_size = png_ptr->current_text_left; + + png_crc_read(png_ptr, (png_bytep)png_ptr->current_text_ptr, text_size); + png_ptr->current_text_left -= text_size; + png_ptr->current_text_ptr += text_size; + } + if (!(png_ptr->current_text_left)) + { + png_textp text_ptr; + png_charp text; + png_charp key; + int ret; + + if (png_ptr->buffer_size < 4) + { + png_push_save_buffer(png_ptr); + return; + } + + png_push_crc_finish(png_ptr); + +#ifdef PNG_MAX_MALLOC_64K + if (png_ptr->skip_length) + return; +#endif + + key = png_ptr->current_text; + + for (text = key; *text; text++) + /* Empty loop */ ; + + if (text < key + png_ptr->current_text_size) + text++; + + text_ptr = (png_textp)png_malloc(png_ptr, + png_sizeof(png_text)); + text_ptr->compression = PNG_TEXT_COMPRESSION_NONE; + text_ptr->key = key; +#ifdef PNG_iTXt_SUPPORTED + text_ptr->lang = NULL; + text_ptr->lang_key = NULL; +#endif + text_ptr->text = text; + + ret = png_set_text_2(png_ptr, info_ptr, text_ptr, 1); + + png_free(png_ptr, key); + png_free(png_ptr, text_ptr); + png_ptr->current_text = NULL; + + if (ret) + png_warning(png_ptr, "Insufficient memory to store text chunk"); + } +} +#endif + +#ifdef PNG_READ_zTXt_SUPPORTED +void /* PRIVATE */ +png_push_handle_zTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 + length) +{ + if (!(png_ptr->mode & PNG_HAVE_IHDR) || (png_ptr->mode & PNG_HAVE_IEND)) + { + png_error(png_ptr, "Out of place zTXt"); + info_ptr = info_ptr; /* To quiet some compiler warnings */ + } + +#ifdef PNG_MAX_MALLOC_64K + /* We can't handle zTXt chunks > 64K, since we don't have enough space + * to be able to store the uncompressed data. Actually, the threshold + * is probably around 32K, but it isn't as definite as 64K is. + */ + if (length > (png_uint_32)65535L) + { + png_warning(png_ptr, "zTXt chunk too large to fit in memory"); + png_push_crc_skip(png_ptr, length); + return; + } +#endif + + png_ptr->current_text = (png_charp)png_malloc(png_ptr, + (png_size_t)(length + 1)); + png_ptr->current_text[length] = '\0'; + png_ptr->current_text_ptr = png_ptr->current_text; + png_ptr->current_text_size = (png_size_t)length; + png_ptr->current_text_left = (png_size_t)length; + png_ptr->process_mode = PNG_READ_zTXt_MODE; +} + +void /* PRIVATE */ +png_push_read_zTXt(png_structp png_ptr, png_infop info_ptr) +{ + if (png_ptr->buffer_size && png_ptr->current_text_left) + { + png_size_t text_size; + + if (png_ptr->buffer_size < (png_uint_32)png_ptr->current_text_left) + text_size = png_ptr->buffer_size; + + else + text_size = png_ptr->current_text_left; + + png_crc_read(png_ptr, (png_bytep)png_ptr->current_text_ptr, text_size); + png_ptr->current_text_left -= text_size; + png_ptr->current_text_ptr += text_size; + } + if (!(png_ptr->current_text_left)) + { + png_textp text_ptr; + png_charp text; + png_charp key; + int ret; + png_size_t text_size, key_size; + + if (png_ptr->buffer_size < 4) + { + png_push_save_buffer(png_ptr); + return; + } + + png_push_crc_finish(png_ptr); + + key = png_ptr->current_text; + + for (text = key; *text; text++) + /* Empty loop */ ; + + /* zTXt can't have zero text */ + if (text >= key + png_ptr->current_text_size) + { + png_ptr->current_text = NULL; + png_free(png_ptr, key); + return; + } + + text++; + + if (*text != PNG_TEXT_COMPRESSION_zTXt) /* Check compression byte */ + { + png_ptr->current_text = NULL; + png_free(png_ptr, key); + return; + } + + text++; + + png_ptr->zstream.next_in = (png_bytep )text; + png_ptr->zstream.avail_in = (uInt)(png_ptr->current_text_size - + (text - key)); + png_ptr->zstream.next_out = png_ptr->zbuf; + png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size; + + key_size = text - key; + text_size = 0; + text = NULL; + ret = Z_STREAM_END; + + while (png_ptr->zstream.avail_in) + { + ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH); + if (ret != Z_OK && ret != Z_STREAM_END) + { + inflateReset(&png_ptr->zstream); + png_ptr->zstream.avail_in = 0; + png_ptr->current_text = NULL; + png_free(png_ptr, key); + png_free(png_ptr, text); + return; + } + if (!(png_ptr->zstream.avail_out) || ret == Z_STREAM_END) + { + if (text == NULL) + { + text = (png_charp)png_malloc(png_ptr, + (png_ptr->zbuf_size + - png_ptr->zstream.avail_out + key_size + 1)); + + png_memcpy(text + key_size, png_ptr->zbuf, + png_ptr->zbuf_size - png_ptr->zstream.avail_out); + + png_memcpy(text, key, key_size); + + text_size = key_size + png_ptr->zbuf_size - + png_ptr->zstream.avail_out; + + *(text + text_size) = '\0'; + } + else + { + png_charp tmp; + + tmp = text; + text = (png_charp)png_malloc(png_ptr, text_size + + (png_ptr->zbuf_size + - png_ptr->zstream.avail_out + 1)); + + png_memcpy(text, tmp, text_size); + png_free(png_ptr, tmp); + + png_memcpy(text + text_size, png_ptr->zbuf, + png_ptr->zbuf_size - png_ptr->zstream.avail_out); + + text_size += png_ptr->zbuf_size - png_ptr->zstream.avail_out; + *(text + text_size) = '\0'; + } + if (ret != Z_STREAM_END) + { + png_ptr->zstream.next_out = png_ptr->zbuf; + png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size; + } + } + else + { + break; + } + + if (ret == Z_STREAM_END) + break; + } + + inflateReset(&png_ptr->zstream); + png_ptr->zstream.avail_in = 0; + + if (ret != Z_STREAM_END) + { + png_ptr->current_text = NULL; + png_free(png_ptr, key); + png_free(png_ptr, text); + return; + } + + png_ptr->current_text = NULL; + png_free(png_ptr, key); + key = text; + text += key_size; + + text_ptr = (png_textp)png_malloc(png_ptr, + png_sizeof(png_text)); + text_ptr->compression = PNG_TEXT_COMPRESSION_zTXt; + text_ptr->key = key; +#ifdef PNG_iTXt_SUPPORTED + text_ptr->lang = NULL; + text_ptr->lang_key = NULL; +#endif + text_ptr->text = text; + + ret = png_set_text_2(png_ptr, info_ptr, text_ptr, 1); + + png_free(png_ptr, key); + png_free(png_ptr, text_ptr); + + if (ret) + png_warning(png_ptr, "Insufficient memory to store text chunk"); + } +} +#endif + +#ifdef PNG_READ_iTXt_SUPPORTED +void /* PRIVATE */ +png_push_handle_iTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 + length) +{ + if (!(png_ptr->mode & PNG_HAVE_IHDR) || (png_ptr->mode & PNG_HAVE_IEND)) + { + png_error(png_ptr, "Out of place iTXt"); + info_ptr = info_ptr; /* To quiet some compiler warnings */ + } + +#ifdef PNG_MAX_MALLOC_64K + png_ptr->skip_length = 0; /* This may not be necessary */ + + if (length > (png_uint_32)65535L) /* Can't hold entire string in memory */ + { + png_warning(png_ptr, "iTXt chunk too large to fit in memory"); + png_ptr->skip_length = length - (png_uint_32)65535L; + length = (png_uint_32)65535L; + } +#endif + + png_ptr->current_text = (png_charp)png_malloc(png_ptr, + (png_size_t)(length + 1)); + png_ptr->current_text[length] = '\0'; + png_ptr->current_text_ptr = png_ptr->current_text; + png_ptr->current_text_size = (png_size_t)length; + png_ptr->current_text_left = (png_size_t)length; + png_ptr->process_mode = PNG_READ_iTXt_MODE; +} + +void /* PRIVATE */ +png_push_read_iTXt(png_structp png_ptr, png_infop info_ptr) +{ + + if (png_ptr->buffer_size && png_ptr->current_text_left) + { + png_size_t text_size; + + if (png_ptr->buffer_size < png_ptr->current_text_left) + text_size = png_ptr->buffer_size; + + else + text_size = png_ptr->current_text_left; + + png_crc_read(png_ptr, (png_bytep)png_ptr->current_text_ptr, text_size); + png_ptr->current_text_left -= text_size; + png_ptr->current_text_ptr += text_size; + } + if (!(png_ptr->current_text_left)) + { + png_textp text_ptr; + png_charp key; + int comp_flag; + png_charp lang; + png_charp lang_key; + png_charp text; + int ret; + + if (png_ptr->buffer_size < 4) + { + png_push_save_buffer(png_ptr); + return; + } + + png_push_crc_finish(png_ptr); + +#ifdef PNG_MAX_MALLOC_64K + if (png_ptr->skip_length) + return; +#endif + + key = png_ptr->current_text; + + for (lang = key; *lang; lang++) + /* Empty loop */ ; + + if (lang < key + png_ptr->current_text_size - 3) + lang++; + + comp_flag = *lang++; + lang++; /* Skip comp_type, always zero */ + + for (lang_key = lang; *lang_key; lang_key++) + /* Empty loop */ ; + + lang_key++; /* Skip NUL separator */ + + text=lang_key; + + if (lang_key < key + png_ptr->current_text_size - 1) + { + for (; *text; text++) + /* Empty loop */ ; + } + + if (text < key + png_ptr->current_text_size) + text++; + + text_ptr = (png_textp)png_malloc(png_ptr, + png_sizeof(png_text)); + + text_ptr->compression = comp_flag + 2; + text_ptr->key = key; + text_ptr->lang = lang; + text_ptr->lang_key = lang_key; + text_ptr->text = text; + text_ptr->text_length = 0; + text_ptr->itxt_length = png_strlen(text); + + ret = png_set_text_2(png_ptr, info_ptr, text_ptr, 1); + + png_ptr->current_text = NULL; + + png_free(png_ptr, text_ptr); + if (ret) + png_warning(png_ptr, "Insufficient memory to store iTXt chunk"); + } +} +#endif + +/* This function is called when we haven't found a handler for this + * chunk. If there isn't a problem with the chunk itself (ie a bad chunk + * name or a critical chunk), the chunk is (currently) silently ignored. + */ +void /* PRIVATE */ +png_push_handle_unknown(png_structp png_ptr, png_infop info_ptr, png_uint_32 + length) +{ + png_uint_32 skip = 0; + + if (!(png_ptr->chunk_name[0] & 0x20)) + { +#ifdef PNG_READ_UNKNOWN_CHUNKS_SUPPORTED + if (png_handle_as_unknown(png_ptr, png_ptr->chunk_name) != + PNG_HANDLE_CHUNK_ALWAYS +#ifdef PNG_READ_USER_CHUNKS_SUPPORTED + && png_ptr->read_user_chunk_fn == NULL +#endif + ) +#endif + png_chunk_error(png_ptr, "unknown critical chunk"); + + info_ptr = info_ptr; /* To quiet some compiler warnings */ + } + +#ifdef PNG_READ_UNKNOWN_CHUNKS_SUPPORTED + if (png_ptr->flags & PNG_FLAG_KEEP_UNKNOWN_CHUNKS) + { +#ifdef PNG_MAX_MALLOC_64K + if (length > (png_uint_32)65535L) + { + png_warning(png_ptr, "unknown chunk too large to fit in memory"); + skip = length - (png_uint_32)65535L; + length = (png_uint_32)65535L; + } +#endif + png_memcpy((png_charp)png_ptr->unknown_chunk.name, + (png_charp)png_ptr->chunk_name, + png_sizeof(png_ptr->unknown_chunk.name)); + png_ptr->unknown_chunk.name[png_sizeof(png_ptr->unknown_chunk.name) - 1] + = '\0'; + + png_ptr->unknown_chunk.size = (png_size_t)length; + + if (length == 0) + png_ptr->unknown_chunk.data = NULL; + + else + { + png_ptr->unknown_chunk.data = (png_bytep)png_malloc(png_ptr, + (png_size_t)length); + png_crc_read(png_ptr, (png_bytep)png_ptr->unknown_chunk.data, length); + } + +#ifdef PNG_READ_USER_CHUNKS_SUPPORTED + if (png_ptr->read_user_chunk_fn != NULL) + { + /* Callback to user unknown chunk handler */ + int ret; + ret = (*(png_ptr->read_user_chunk_fn)) + (png_ptr, &png_ptr->unknown_chunk); + + if (ret < 0) + png_chunk_error(png_ptr, "error in user chunk"); + + if (ret == 0) + { + if (!(png_ptr->chunk_name[0] & 0x20)) + if (png_handle_as_unknown(png_ptr, png_ptr->chunk_name) != + PNG_HANDLE_CHUNK_ALWAYS) + png_chunk_error(png_ptr, "unknown critical chunk"); + png_set_unknown_chunks(png_ptr, info_ptr, + &png_ptr->unknown_chunk, 1); + } + } + + else +#endif + png_set_unknown_chunks(png_ptr, info_ptr, &png_ptr->unknown_chunk, 1); + png_free(png_ptr, png_ptr->unknown_chunk.data); + png_ptr->unknown_chunk.data = NULL; + } + + else +#endif + skip=length; + png_push_crc_skip(png_ptr, skip); +} + +void /* PRIVATE */ +png_push_have_info(png_structp png_ptr, png_infop info_ptr) +{ + if (png_ptr->info_fn != NULL) + (*(png_ptr->info_fn))(png_ptr, info_ptr); +} + +void /* PRIVATE */ +png_push_have_end(png_structp png_ptr, png_infop info_ptr) +{ + if (png_ptr->end_fn != NULL) + (*(png_ptr->end_fn))(png_ptr, info_ptr); +} + +void /* PRIVATE */ +png_push_have_row(png_structp png_ptr, png_bytep row) +{ + if (png_ptr->row_fn != NULL) + (*(png_ptr->row_fn))(png_ptr, row, png_ptr->row_number, + (int)png_ptr->pass); +} + +void PNGAPI +png_progressive_combine_row (png_structp png_ptr, + png_bytep old_row, png_bytep new_row) +{ + PNG_CONST int FARDATA png_pass_dsp_mask[7] = + {0xff, 0x0f, 0xff, 0x33, 0xff, 0x55, 0xff}; + + if (png_ptr == NULL) + return; + + if (new_row != NULL) /* new_row must == png_ptr->row_buf here. */ + png_combine_row(png_ptr, old_row, png_pass_dsp_mask[png_ptr->pass]); +} + +void PNGAPI +png_set_progressive_read_fn(png_structp png_ptr, png_voidp progressive_ptr, + png_progressive_info_ptr info_fn, png_progressive_row_ptr row_fn, + png_progressive_end_ptr end_fn) +{ + if (png_ptr == NULL) + return; + + png_ptr->info_fn = info_fn; + png_ptr->row_fn = row_fn; + png_ptr->end_fn = end_fn; + + png_set_read_fn(png_ptr, progressive_ptr, png_push_fill_buffer); +} + +png_voidp PNGAPI +png_get_progressive_ptr(png_structp png_ptr) +{ + if (png_ptr == NULL) + return (NULL); + + return png_ptr->io_ptr; +} +#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */ diff --git a/libpng/pngpriv.h b/libpng/pngpriv.h new file mode 100644 index 0000000..8b0621c --- /dev/null +++ b/libpng/pngpriv.h @@ -0,0 +1,954 @@ + +/* pngpriv.h - private declarations for use inside libpng + * + * libpng version 1.4.4 - September 23, 2010 + * For conditions of distribution and use, see copyright notice in png.h + * Copyright (c) 1998-2010 Glenn Randers-Pehrson + * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) + * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) + * + * This code is released under the libpng license. + * For conditions of distribution and use, see the disclaimer + * and license in png.h + */ + +/* The symbols declared in this file (including the functions declared + * as PNG_EXTERN) are PRIVATE. They are not part of the libpng public + * interface, and are not recommended for use by regular applications. + * Some of them may become public in the future; others may stay private, + * change in an incompatible way, or even disappear. + * Although the libpng users are not forbidden to include this header, + * they should be well aware of the issues that may arise from doing so. + */ + +#ifndef PNGPRIV_H +#define PNGPRIV_H + +#ifndef PNG_VERSION_INFO_ONLY + +#include + +#ifndef PNG_EXTERN +/* The functions exported by PNG_EXTERN are internal functions, which + * aren't usually used outside the library (as far as I know), so it is + * debatable if they should be exported at all. In the future, when it + * is possible to have run-time registry of chunk-handling functions, + * some of these will be made available again. +# define PNG_EXTERN extern + */ +# define PNG_EXTERN +#endif + +/* Other defines specific to compilers can go here. Try to keep + * them inside an appropriate ifdef/endif pair for portability. + */ + +#ifdef PNG_FLOATING_POINT_SUPPORTED +# ifdef MACOS + /* We need to check that hasn't already been included earlier + * as it seems it doesn't agree with , yet we should really use + * if possible. + */ +# if !defined(__MATH_H__) && !defined(__MATH_H) && !defined(__cmath__) +# include +# endif +# else +# include +# endif +# if defined(_AMIGA) && defined(__SASC) && defined(_M68881) + /* Amiga SAS/C: We must include builtin FPU functions when compiling using + * MATH=68881 + */ +# include +# endif +#endif + +/* Codewarrior on NT has linking problems without this. */ +#if (defined(__MWERKS__) && defined(WIN32)) || defined(__STDC__) +# define PNG_ALWAYS_EXTERN +#endif + +/* This provides the non-ANSI (far) memory allocation routines. */ +#if defined(__TURBOC__) && defined(__MSDOS__) +# include +# include +#endif + +#if defined(WIN32) || defined(_Windows) || defined(_WINDOWS) || \ + defined(_WIN32) || defined(__WIN32__) +# include /* defines _WINDOWS_ macro */ +#endif + +/* Various modes of operation. Note that after an init, mode is set to + * zero automatically when the structure is created. + */ +#define PNG_HAVE_IHDR 0x01 +#define PNG_HAVE_PLTE 0x02 +#define PNG_HAVE_IDAT 0x04 +#define PNG_AFTER_IDAT 0x08 /* Have complete zlib datastream */ +#define PNG_HAVE_IEND 0x10 +#define PNG_HAVE_gAMA 0x20 +#define PNG_HAVE_cHRM 0x40 +#define PNG_HAVE_sRGB 0x80 +#define PNG_HAVE_CHUNK_HEADER 0x100 +#define PNG_WROTE_tIME 0x200 +#define PNG_WROTE_INFO_BEFORE_PLTE 0x400 +#define PNG_BACKGROUND_IS_GRAY 0x800 +#define PNG_HAVE_PNG_SIGNATURE 0x1000 +#define PNG_HAVE_CHUNK_AFTER_IDAT 0x2000 /* Have another chunk after IDAT */ + +/* Flags for the transformations the PNG library does on the image data */ +#define PNG_BGR 0x0001 +#define PNG_INTERLACE 0x0002 +#define PNG_PACK 0x0004 +#define PNG_SHIFT 0x0008 +#define PNG_SWAP_BYTES 0x0010 +#define PNG_INVERT_MONO 0x0020 +#define PNG_QUANTIZE 0x0040 /* formerly PNG_DITHER */ +#define PNG_BACKGROUND 0x0080 +#define PNG_BACKGROUND_EXPAND 0x0100 + /* 0x0200 unused */ +#define PNG_16_TO_8 0x0400 +#define PNG_RGBA 0x0800 +#define PNG_EXPAND 0x1000 +#define PNG_GAMMA 0x2000 +#define PNG_GRAY_TO_RGB 0x4000 +#define PNG_FILLER 0x8000L +#define PNG_PACKSWAP 0x10000L +#define PNG_SWAP_ALPHA 0x20000L +#define PNG_STRIP_ALPHA 0x40000L +#define PNG_INVERT_ALPHA 0x80000L +#define PNG_USER_TRANSFORM 0x100000L +#define PNG_RGB_TO_GRAY_ERR 0x200000L +#define PNG_RGB_TO_GRAY_WARN 0x400000L +#define PNG_RGB_TO_GRAY 0x600000L /* two bits, RGB_TO_GRAY_ERR|WARN */ + /* 0x800000L Unused */ +#define PNG_ADD_ALPHA 0x1000000L /* Added to libpng-1.2.7 */ +#define PNG_EXPAND_tRNS 0x2000000L /* Added to libpng-1.2.9 */ + /* 0x4000000L unused */ + /* 0x8000000L unused */ + /* 0x10000000L unused */ + /* 0x20000000L unused */ + /* 0x40000000L unused */ + +/* Flags for png_create_struct */ +#define PNG_STRUCT_PNG 0x0001 +#define PNG_STRUCT_INFO 0x0002 + +/* Scaling factor for filter heuristic weighting calculations */ +#define PNG_WEIGHT_SHIFT 8 +#define PNG_WEIGHT_FACTOR (1<<(PNG_WEIGHT_SHIFT)) +#define PNG_COST_SHIFT 3 +#define PNG_COST_FACTOR (1<<(PNG_COST_SHIFT)) + +/* Flags for the png_ptr->flags rather than declaring a byte for each one */ +#define PNG_FLAG_ZLIB_CUSTOM_STRATEGY 0x0001 +#define PNG_FLAG_ZLIB_CUSTOM_LEVEL 0x0002 +#define PNG_FLAG_ZLIB_CUSTOM_MEM_LEVEL 0x0004 +#define PNG_FLAG_ZLIB_CUSTOM_WINDOW_BITS 0x0008 +#define PNG_FLAG_ZLIB_CUSTOM_METHOD 0x0010 +#define PNG_FLAG_ZLIB_FINISHED 0x0020 +#define PNG_FLAG_ROW_INIT 0x0040 +#define PNG_FLAG_FILLER_AFTER 0x0080 +#define PNG_FLAG_CRC_ANCILLARY_USE 0x0100 +#define PNG_FLAG_CRC_ANCILLARY_NOWARN 0x0200 +#define PNG_FLAG_CRC_CRITICAL_USE 0x0400 +#define PNG_FLAG_CRC_CRITICAL_IGNORE 0x0800 + /* 0x1000 unused */ + /* 0x2000 unused */ + /* 0x4000 unused */ +#define PNG_FLAG_KEEP_UNKNOWN_CHUNKS 0x8000L +#define PNG_FLAG_KEEP_UNSAFE_CHUNKS 0x10000L +#define PNG_FLAG_LIBRARY_MISMATCH 0x20000L +#define PNG_FLAG_STRIP_ERROR_NUMBERS 0x40000L +#define PNG_FLAG_STRIP_ERROR_TEXT 0x80000L +#define PNG_FLAG_MALLOC_NULL_MEM_OK 0x100000L +#define PNG_FLAG_ADD_ALPHA 0x200000L /* Added to libpng-1.2.8 */ +#define PNG_FLAG_STRIP_ALPHA 0x400000L /* Added to libpng-1.2.8 */ +#define PNG_FLAG_BENIGN_ERRORS_WARN 0x800000L /* Added to libpng-1.4.0 */ + /* 0x1000000L unused */ + /* 0x2000000L unused */ + /* 0x4000000L unused */ + /* 0x8000000L unused */ + /* 0x10000000L unused */ + /* 0x20000000L unused */ + /* 0x40000000L unused */ + +#define PNG_FLAG_CRC_ANCILLARY_MASK (PNG_FLAG_CRC_ANCILLARY_USE | \ + PNG_FLAG_CRC_ANCILLARY_NOWARN) + +#define PNG_FLAG_CRC_CRITICAL_MASK (PNG_FLAG_CRC_CRITICAL_USE | \ + PNG_FLAG_CRC_CRITICAL_IGNORE) + +#define PNG_FLAG_CRC_MASK (PNG_FLAG_CRC_ANCILLARY_MASK | \ + PNG_FLAG_CRC_CRITICAL_MASK) + +/* Save typing and make code easier to understand */ + +#define PNG_COLOR_DIST(c1, c2) (abs((int)((c1).red) - (int)((c2).red)) + \ + abs((int)((c1).green) - (int)((c2).green)) + \ + abs((int)((c1).blue) - (int)((c2).blue))) + +/* Added to libpng-1.2.6 JB */ +#define PNG_ROWBYTES(pixel_bits, width) \ + ((pixel_bits) >= 8 ? \ + ((png_size_t)(width) * (((png_size_t)(pixel_bits)) >> 3)) : \ + (( ((png_size_t)(width) * ((png_size_t)(pixel_bits))) + 7) >> 3) ) + +/* PNG_OUT_OF_RANGE returns true if value is outside the range + * ideal-delta..ideal+delta. Each argument is evaluated twice. + * "ideal" and "delta" should be constants, normally simple + * integers, "value" a variable. Added to libpng-1.2.6 JB + */ +#define PNG_OUT_OF_RANGE(value, ideal, delta) \ + ( (value) < (ideal)-(delta) || (value) > (ideal)+(delta) ) + +/* Constant strings for known chunk types. If you need to add a chunk, + * define the name here, and add an invocation of the macro wherever it's + * needed. + */ +#define PNG_IHDR PNG_CONST png_byte png_IHDR[5] = { 73, 72, 68, 82, '\0'} +#define PNG_IDAT PNG_CONST png_byte png_IDAT[5] = { 73, 68, 65, 84, '\0'} +#define PNG_IEND PNG_CONST png_byte png_IEND[5] = { 73, 69, 78, 68, '\0'} +#define PNG_PLTE PNG_CONST png_byte png_PLTE[5] = { 80, 76, 84, 69, '\0'} +#define PNG_bKGD PNG_CONST png_byte png_bKGD[5] = { 98, 75, 71, 68, '\0'} +#define PNG_cHRM PNG_CONST png_byte png_cHRM[5] = { 99, 72, 82, 77, '\0'} +#define PNG_gAMA PNG_CONST png_byte png_gAMA[5] = {103, 65, 77, 65, '\0'} +#define PNG_hIST PNG_CONST png_byte png_hIST[5] = {104, 73, 83, 84, '\0'} +#define PNG_iCCP PNG_CONST png_byte png_iCCP[5] = {105, 67, 67, 80, '\0'} +#define PNG_iTXt PNG_CONST png_byte png_iTXt[5] = {105, 84, 88, 116, '\0'} +#define PNG_oFFs PNG_CONST png_byte png_oFFs[5] = {111, 70, 70, 115, '\0'} +#define PNG_pCAL PNG_CONST png_byte png_pCAL[5] = {112, 67, 65, 76, '\0'} +#define PNG_sCAL PNG_CONST png_byte png_sCAL[5] = {115, 67, 65, 76, '\0'} +#define PNG_pHYs PNG_CONST png_byte png_pHYs[5] = {112, 72, 89, 115, '\0'} +#define PNG_sBIT PNG_CONST png_byte png_sBIT[5] = {115, 66, 73, 84, '\0'} +#define PNG_sPLT PNG_CONST png_byte png_sPLT[5] = {115, 80, 76, 84, '\0'} +#define PNG_sRGB PNG_CONST png_byte png_sRGB[5] = {115, 82, 71, 66, '\0'} +#define PNG_sTER PNG_CONST png_byte png_sTER[5] = {115, 84, 69, 82, '\0'} +#define PNG_tEXt PNG_CONST png_byte png_tEXt[5] = {116, 69, 88, 116, '\0'} +#define PNG_tIME PNG_CONST png_byte png_tIME[5] = {116, 73, 77, 69, '\0'} +#define PNG_tRNS PNG_CONST png_byte png_tRNS[5] = {116, 82, 78, 83, '\0'} +#define PNG_zTXt PNG_CONST png_byte png_zTXt[5] = {122, 84, 88, 116, '\0'} + + +/* Inhibit C++ name-mangling for libpng functions but not for system calls. */ +#ifdef __cplusplus +extern "C" { +#endif /* __cplusplus */ + +/* These functions are used internally in the code. They generally + * shouldn't be used unless you are writing code to add or replace some + * functionality in libpng. More information about most functions can + * be found in the files where the functions are located. + */ + +/* Allocate memory for an internal libpng struct */ +PNG_EXTERN png_voidp png_create_struct PNGARG((int type)); + +/* Free memory from internal libpng struct */ +PNG_EXTERN void png_destroy_struct PNGARG((png_voidp struct_ptr)); + +PNG_EXTERN png_voidp png_create_struct_2 PNGARG((int type, png_malloc_ptr + malloc_fn, png_voidp mem_ptr)); +PNG_EXTERN void png_destroy_struct_2 PNGARG((png_voidp struct_ptr, + png_free_ptr free_fn, png_voidp mem_ptr)); + +/* Free any memory that info_ptr points to and reset struct. */ +PNG_EXTERN void png_info_destroy PNGARG((png_structp png_ptr, + png_infop info_ptr)); + +/* Function to allocate memory for zlib. PNGAPI is disallowed. */ +PNG_EXTERN voidpf png_zalloc PNGARG((voidpf png_ptr, uInt items, uInt size)); + +/* Function to free memory for zlib. PNGAPI is disallowed. */ +PNG_EXTERN void png_zfree PNGARG((voidpf png_ptr, voidpf ptr)); + +/* Next four functions are used internally as callbacks. PNGAPI is required + * but not PNG_EXPORT. PNGAPI added at libpng version 1.2.3. */ + +PNG_EXTERN void PNGAPI png_default_read_data PNGARG((png_structp png_ptr, + png_bytep data, png_size_t length)); + +#ifdef PNG_PROGRESSIVE_READ_SUPPORTED +PNG_EXTERN void PNGAPI png_push_fill_buffer PNGARG((png_structp png_ptr, + png_bytep buffer, png_size_t length)); +#endif + +PNG_EXTERN void PNGAPI png_default_write_data PNGARG((png_structp png_ptr, + png_bytep data, png_size_t length)); + +#ifdef PNG_WRITE_FLUSH_SUPPORTED +#ifdef PNG_STDIO_SUPPORTED +PNG_EXTERN void PNGAPI png_default_flush PNGARG((png_structp png_ptr)); +#endif +#endif + +/* Reset the CRC variable */ +PNG_EXTERN void png_reset_crc PNGARG((png_structp png_ptr)); + +/* Write the "data" buffer to whatever output you are using */ +PNG_EXTERN void png_write_data PNGARG((png_structp png_ptr, png_bytep data, + png_size_t length)); + +/* Read the chunk header (length + type name) */ +PNG_EXTERN png_uint_32 png_read_chunk_header PNGARG((png_structp png_ptr)); + +/* Read data from whatever input you are using into the "data" buffer */ +PNG_EXTERN void png_read_data PNGARG((png_structp png_ptr, png_bytep data, + png_size_t length)); + +/* Read bytes into buf, and update png_ptr->crc */ +PNG_EXTERN void png_crc_read PNGARG((png_structp png_ptr, png_bytep buf, + png_size_t length)); + +/* Decompress data in a chunk that uses compression */ +#if defined(PNG_zTXt_SUPPORTED) || defined(PNG_iTXt_SUPPORTED) || \ + defined(PNG_iCCP_SUPPORTED) || defined(PNG_sPLT_SUPPORTED) +PNG_EXTERN void png_decompress_chunk PNGARG((png_structp png_ptr, + int comp_type, png_size_t chunklength, png_size_t prefix_length, + png_size_t *data_length)); +#endif + +/* Read "skip" bytes, read the file crc, and (optionally) verify png_ptr->crc */ +PNG_EXTERN int png_crc_finish PNGARG((png_structp png_ptr, png_uint_32 skip)); + +/* Read the CRC from the file and compare it to the libpng calculated CRC */ +PNG_EXTERN int png_crc_error PNGARG((png_structp png_ptr)); + +/* Calculate the CRC over a section of data. Note that we are only + * passing a maximum of 64K on systems that have this as a memory limit, + * since this is the maximum buffer size we can specify. + */ +PNG_EXTERN void png_calculate_crc PNGARG((png_structp png_ptr, png_bytep ptr, + png_size_t length)); + +#ifdef PNG_WRITE_FLUSH_SUPPORTED +PNG_EXTERN void png_flush PNGARG((png_structp png_ptr)); +#endif + +/* Write various chunks */ + +/* Write the IHDR chunk, and update the png_struct with the necessary + * information. + */ +PNG_EXTERN void png_write_IHDR PNGARG((png_structp png_ptr, png_uint_32 width, + png_uint_32 height, + int bit_depth, int color_type, int compression_method, int filter_method, + int interlace_method)); + +PNG_EXTERN void png_write_PLTE PNGARG((png_structp png_ptr, png_colorp palette, + png_uint_32 num_pal)); + +PNG_EXTERN void png_write_IDAT PNGARG((png_structp png_ptr, png_bytep data, + png_size_t length)); + +PNG_EXTERN void png_write_IEND PNGARG((png_structp png_ptr)); + +#ifdef PNG_WRITE_gAMA_SUPPORTED +#ifdef PNG_FLOATING_POINT_SUPPORTED +PNG_EXTERN void png_write_gAMA PNGARG((png_structp png_ptr, double file_gamma)); +#endif +#ifdef PNG_FIXED_POINT_SUPPORTED +PNG_EXTERN void png_write_gAMA_fixed PNGARG((png_structp png_ptr, + png_fixed_point file_gamma)); +#endif +#endif + +#ifdef PNG_WRITE_sBIT_SUPPORTED +PNG_EXTERN void png_write_sBIT PNGARG((png_structp png_ptr, png_color_8p sbit, + int color_type)); +#endif + +#ifdef PNG_WRITE_cHRM_SUPPORTED +#ifdef PNG_FLOATING_POINT_SUPPORTED +PNG_EXTERN void png_write_cHRM PNGARG((png_structp png_ptr, + double white_x, double white_y, + double red_x, double red_y, double green_x, double green_y, + double blue_x, double blue_y)); +#endif +PNG_EXTERN void png_write_cHRM_fixed PNGARG((png_structp png_ptr, + png_fixed_point int_white_x, png_fixed_point int_white_y, + png_fixed_point int_red_x, png_fixed_point int_red_y, png_fixed_point + int_green_x, png_fixed_point int_green_y, png_fixed_point int_blue_x, + png_fixed_point int_blue_y)); +#endif + +#ifdef PNG_WRITE_sRGB_SUPPORTED +PNG_EXTERN void png_write_sRGB PNGARG((png_structp png_ptr, + int intent)); +#endif + +#ifdef PNG_WRITE_iCCP_SUPPORTED +PNG_EXTERN void png_write_iCCP PNGARG((png_structp png_ptr, + png_charp name, int compression_type, + png_charp profile, int proflen)); + /* Note to maintainer: profile should be png_bytep */ +#endif + +#ifdef PNG_WRITE_sPLT_SUPPORTED +PNG_EXTERN void png_write_sPLT PNGARG((png_structp png_ptr, + png_sPLT_tp palette)); +#endif + +#ifdef PNG_WRITE_tRNS_SUPPORTED +PNG_EXTERN void png_write_tRNS PNGARG((png_structp png_ptr, png_bytep trans, + png_color_16p values, int number, int color_type)); +#endif + +#ifdef PNG_WRITE_bKGD_SUPPORTED +PNG_EXTERN void png_write_bKGD PNGARG((png_structp png_ptr, + png_color_16p values, int color_type)); +#endif + +#ifdef PNG_WRITE_hIST_SUPPORTED +PNG_EXTERN void png_write_hIST PNGARG((png_structp png_ptr, png_uint_16p hist, + int num_hist)); +#endif + +#if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_pCAL_SUPPORTED) || \ + defined(PNG_WRITE_iCCP_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED) +PNG_EXTERN png_size_t png_check_keyword PNGARG((png_structp png_ptr, + png_charp key, png_charpp new_key)); +#endif + +#ifdef PNG_WRITE_tEXt_SUPPORTED +PNG_EXTERN void png_write_tEXt PNGARG((png_structp png_ptr, png_charp key, + png_charp text, png_size_t text_len)); +#endif + +#ifdef PNG_WRITE_zTXt_SUPPORTED +PNG_EXTERN void png_write_zTXt PNGARG((png_structp png_ptr, png_charp key, + png_charp text, png_size_t text_len, int compression)); +#endif + +#ifdef PNG_WRITE_iTXt_SUPPORTED +PNG_EXTERN void png_write_iTXt PNGARG((png_structp png_ptr, + int compression, png_charp key, png_charp lang, png_charp lang_key, + png_charp text)); +#endif + +#ifdef PNG_TEXT_SUPPORTED /* Added at version 1.0.14 and 1.2.4 */ +PNG_EXTERN int png_set_text_2 PNGARG((png_structp png_ptr, + png_infop info_ptr, png_textp text_ptr, int num_text)); +#endif + +#ifdef PNG_WRITE_oFFs_SUPPORTED +PNG_EXTERN void png_write_oFFs PNGARG((png_structp png_ptr, + png_int_32 x_offset, png_int_32 y_offset, int unit_type)); +#endif + +#ifdef PNG_WRITE_pCAL_SUPPORTED +PNG_EXTERN void png_write_pCAL PNGARG((png_structp png_ptr, png_charp purpose, + png_int_32 X0, png_int_32 X1, int type, int nparams, + png_charp units, png_charpp params)); +#endif + +#ifdef PNG_WRITE_pHYs_SUPPORTED +PNG_EXTERN void png_write_pHYs PNGARG((png_structp png_ptr, + png_uint_32 x_pixels_per_unit, png_uint_32 y_pixels_per_unit, + int unit_type)); +#endif + +#ifdef PNG_WRITE_tIME_SUPPORTED +PNG_EXTERN void png_write_tIME PNGARG((png_structp png_ptr, + png_timep mod_time)); +#endif + +#ifdef PNG_WRITE_sCAL_SUPPORTED +#if defined(PNG_FLOATING_POINT_SUPPORTED) && defined(PNG_STDIO_SUPPORTED) +PNG_EXTERN void png_write_sCAL PNGARG((png_structp png_ptr, + int unit, double width, double height)); +#else +#ifdef PNG_FIXED_POINT_SUPPORTED +PNG_EXTERN void png_write_sCAL_s PNGARG((png_structp png_ptr, + int unit, png_charp width, png_charp height)); +#endif +#endif +#endif + +/* Called when finished processing a row of data */ +PNG_EXTERN void png_write_finish_row PNGARG((png_structp png_ptr)); + +/* Internal use only. Called before first row of data */ +PNG_EXTERN void png_write_start_row PNGARG((png_structp png_ptr)); + +#ifdef PNG_READ_GAMMA_SUPPORTED +PNG_EXTERN void png_build_gamma_table PNGARG((png_structp png_ptr, + png_byte bit_depth)); +#endif + +/* Combine a row of data, dealing with alpha, etc. if requested */ +PNG_EXTERN void png_combine_row PNGARG((png_structp png_ptr, png_bytep row, + int mask)); + +#ifdef PNG_READ_INTERLACING_SUPPORTED +/* Expand an interlaced row */ +/* OLD pre-1.0.9 interface: +PNG_EXTERN void png_do_read_interlace PNGARG((png_row_infop row_info, + png_bytep row, int pass, png_uint_32 transformations)); + */ +PNG_EXTERN void png_do_read_interlace PNGARG((png_structp png_ptr)); +#endif + +/* GRR TO DO (2.0 or whenever): simplify other internal calling interfaces */ + +#ifdef PNG_WRITE_INTERLACING_SUPPORTED +/* Grab pixels out of a row for an interlaced pass */ +PNG_EXTERN void png_do_write_interlace PNGARG((png_row_infop row_info, + png_bytep row, int pass)); +#endif + +/* Unfilter a row */ +PNG_EXTERN void png_read_filter_row PNGARG((png_structp png_ptr, + png_row_infop row_info, png_bytep row, png_bytep prev_row, int filter)); + +/* Choose the best filter to use and filter the row data */ +PNG_EXTERN void png_write_find_filter PNGARG((png_structp png_ptr, + png_row_infop row_info)); + +/* Write out the filtered row. */ +PNG_EXTERN void png_write_filtered_row PNGARG((png_structp png_ptr, + png_bytep filtered_row)); +/* Finish a row while reading, dealing with interlacing passes, etc. */ +PNG_EXTERN void png_read_finish_row PNGARG((png_structp png_ptr)); + +/* Initialize the row buffers, etc. */ +PNG_EXTERN void png_read_start_row PNGARG((png_structp png_ptr)); +/* Optional call to update the users info structure */ +PNG_EXTERN void png_read_transform_info PNGARG((png_structp png_ptr, + png_infop info_ptr)); + +/* These are the functions that do the transformations */ +#ifdef PNG_READ_FILLER_SUPPORTED +PNG_EXTERN void png_do_read_filler PNGARG((png_row_infop row_info, + png_bytep row, png_uint_32 filler, png_uint_32 flags)); +#endif + +#ifdef PNG_READ_SWAP_ALPHA_SUPPORTED +PNG_EXTERN void png_do_read_swap_alpha PNGARG((png_row_infop row_info, + png_bytep row)); +#endif + +#ifdef PNG_WRITE_SWAP_ALPHA_SUPPORTED +PNG_EXTERN void png_do_write_swap_alpha PNGARG((png_row_infop row_info, + png_bytep row)); +#endif + +#ifdef PNG_READ_INVERT_ALPHA_SUPPORTED +PNG_EXTERN void png_do_read_invert_alpha PNGARG((png_row_infop row_info, + png_bytep row)); +#endif + +#ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED +PNG_EXTERN void png_do_write_invert_alpha PNGARG((png_row_infop row_info, + png_bytep row)); +#endif + +#if defined(PNG_WRITE_FILLER_SUPPORTED) || \ + defined(PNG_READ_STRIP_ALPHA_SUPPORTED) +PNG_EXTERN void png_do_strip_filler PNGARG((png_row_infop row_info, + png_bytep row, png_uint_32 flags)); +#endif + +#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED) +PNG_EXTERN void png_do_swap PNGARG((png_row_infop row_info, png_bytep row)); +#endif + +#if defined(PNG_READ_PACKSWAP_SUPPORTED) || \ + defined(PNG_WRITE_PACKSWAP_SUPPORTED) +PNG_EXTERN void png_do_packswap PNGARG((png_row_infop row_info, png_bytep row)); +#endif + +#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED +PNG_EXTERN int png_do_rgb_to_gray PNGARG((png_structp png_ptr, png_row_infop + row_info, png_bytep row)); +#endif + +#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED +PNG_EXTERN void png_do_gray_to_rgb PNGARG((png_row_infop row_info, + png_bytep row)); +#endif + +#ifdef PNG_READ_PACK_SUPPORTED +PNG_EXTERN void png_do_unpack PNGARG((png_row_infop row_info, png_bytep row)); +#endif + +#ifdef PNG_READ_SHIFT_SUPPORTED +PNG_EXTERN void png_do_unshift PNGARG((png_row_infop row_info, png_bytep row, + png_color_8p sig_bits)); +#endif + +#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED) +PNG_EXTERN void png_do_invert PNGARG((png_row_infop row_info, png_bytep row)); +#endif + +#ifdef PNG_READ_16_TO_8_SUPPORTED +PNG_EXTERN void png_do_chop PNGARG((png_row_infop row_info, png_bytep row)); +#endif + +#ifdef PNG_READ_QUANTIZE_SUPPORTED +PNG_EXTERN void png_do_quantize PNGARG((png_row_infop row_info, + png_bytep row, png_bytep palette_lookup, png_bytep quantize_lookup)); + +# ifdef PNG_CORRECT_PALETTE_SUPPORTED +PNG_EXTERN void png_correct_palette PNGARG((png_structp png_ptr, + png_colorp palette, int num_palette)); +# endif +#endif + +#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED) +PNG_EXTERN void png_do_bgr PNGARG((png_row_infop row_info, png_bytep row)); +#endif + +#ifdef PNG_WRITE_PACK_SUPPORTED +PNG_EXTERN void png_do_pack PNGARG((png_row_infop row_info, + png_bytep row, png_uint_32 bit_depth)); +#endif + +#ifdef PNG_WRITE_SHIFT_SUPPORTED +PNG_EXTERN void png_do_shift PNGARG((png_row_infop row_info, png_bytep row, + png_color_8p bit_depth)); +#endif + +#ifdef PNG_READ_BACKGROUND_SUPPORTED +#ifdef PNG_READ_GAMMA_SUPPORTED +PNG_EXTERN void png_do_background PNGARG((png_row_infop row_info, png_bytep row, + png_color_16p trans_color, png_color_16p background, + png_color_16p background_1, + png_bytep gamma_table, png_bytep gamma_from_1, png_bytep gamma_to_1, + png_uint_16pp gamma_16, png_uint_16pp gamma_16_from_1, + png_uint_16pp gamma_16_to_1, int gamma_shift)); +#else +PNG_EXTERN void png_do_background PNGARG((png_row_infop row_info, png_bytep row, + png_color_16p trans_color, png_color_16p background)); +#endif +#endif + +#ifdef PNG_READ_GAMMA_SUPPORTED +PNG_EXTERN void png_do_gamma PNGARG((png_row_infop row_info, png_bytep row, + png_bytep gamma_table, png_uint_16pp gamma_16_table, + int gamma_shift)); +#endif + +#ifdef PNG_READ_EXPAND_SUPPORTED +PNG_EXTERN void png_do_expand_palette PNGARG((png_row_infop row_info, + png_bytep row, png_colorp palette, png_bytep trans, int num_trans)); +PNG_EXTERN void png_do_expand PNGARG((png_row_infop row_info, + png_bytep row, png_color_16p trans_value)); +#endif + +/* The following decodes the appropriate chunks, and does error correction, + * then calls the appropriate callback for the chunk if it is valid. + */ + +/* Decode the IHDR chunk */ +PNG_EXTERN void png_handle_IHDR PNGARG((png_structp png_ptr, png_infop info_ptr, + png_uint_32 length)); +PNG_EXTERN void png_handle_PLTE PNGARG((png_structp png_ptr, png_infop info_ptr, + png_uint_32 length)); +PNG_EXTERN void png_handle_IEND PNGARG((png_structp png_ptr, png_infop info_ptr, + png_uint_32 length)); + +#ifdef PNG_READ_bKGD_SUPPORTED +PNG_EXTERN void png_handle_bKGD PNGARG((png_structp png_ptr, png_infop info_ptr, + png_uint_32 length)); +#endif + +#ifdef PNG_READ_cHRM_SUPPORTED +PNG_EXTERN void png_handle_cHRM PNGARG((png_structp png_ptr, png_infop info_ptr, + png_uint_32 length)); +#endif + +#ifdef PNG_READ_gAMA_SUPPORTED +PNG_EXTERN void png_handle_gAMA PNGARG((png_structp png_ptr, png_infop info_ptr, + png_uint_32 length)); +#endif + +#ifdef PNG_READ_hIST_SUPPORTED +PNG_EXTERN void png_handle_hIST PNGARG((png_structp png_ptr, png_infop info_ptr, + png_uint_32 length)); +#endif + +#ifdef PNG_READ_iCCP_SUPPORTED +PNG_EXTERN void png_handle_iCCP PNGARG((png_structp png_ptr, png_infop info_ptr, + png_uint_32 length)); +#endif /* PNG_READ_iCCP_SUPPORTED */ + +#ifdef PNG_READ_iTXt_SUPPORTED +PNG_EXTERN void png_handle_iTXt PNGARG((png_structp png_ptr, png_infop info_ptr, + png_uint_32 length)); +#endif + +#ifdef PNG_READ_oFFs_SUPPORTED +PNG_EXTERN void png_handle_oFFs PNGARG((png_structp png_ptr, png_infop info_ptr, + png_uint_32 length)); +#endif + +#ifdef PNG_READ_pCAL_SUPPORTED +PNG_EXTERN void png_handle_pCAL PNGARG((png_structp png_ptr, png_infop info_ptr, + png_uint_32 length)); +#endif + +#ifdef PNG_READ_pHYs_SUPPORTED +PNG_EXTERN void png_handle_pHYs PNGARG((png_structp png_ptr, png_infop info_ptr, + png_uint_32 length)); +#endif + +#ifdef PNG_READ_sBIT_SUPPORTED +PNG_EXTERN void png_handle_sBIT PNGARG((png_structp png_ptr, png_infop info_ptr, + png_uint_32 length)); +#endif + +#ifdef PNG_READ_sCAL_SUPPORTED +PNG_EXTERN void png_handle_sCAL PNGARG((png_structp png_ptr, png_infop info_ptr, + png_uint_32 length)); +#endif + +#ifdef PNG_READ_sPLT_SUPPORTED +PNG_EXTERN void png_handle_sPLT PNGARG((png_structp png_ptr, png_infop info_ptr, + png_uint_32 length)); +#endif /* PNG_READ_sPLT_SUPPORTED */ + +#ifdef PNG_READ_sRGB_SUPPORTED +PNG_EXTERN void png_handle_sRGB PNGARG((png_structp png_ptr, png_infop info_ptr, + png_uint_32 length)); +#endif + +#ifdef PNG_READ_tEXt_SUPPORTED +PNG_EXTERN void png_handle_tEXt PNGARG((png_structp png_ptr, png_infop info_ptr, + png_uint_32 length)); +#endif + +#ifdef PNG_READ_tIME_SUPPORTED +PNG_EXTERN void png_handle_tIME PNGARG((png_structp png_ptr, png_infop info_ptr, + png_uint_32 length)); +#endif + +#ifdef PNG_READ_tRNS_SUPPORTED +PNG_EXTERN void png_handle_tRNS PNGARG((png_structp png_ptr, png_infop info_ptr, + png_uint_32 length)); +#endif + +#ifdef PNG_READ_zTXt_SUPPORTED +PNG_EXTERN void png_handle_zTXt PNGARG((png_structp png_ptr, png_infop info_ptr, + png_uint_32 length)); +#endif + +PNG_EXTERN void png_handle_unknown PNGARG((png_structp png_ptr, + png_infop info_ptr, png_uint_32 length)); + +PNG_EXTERN void png_check_chunk_name PNGARG((png_structp png_ptr, + png_bytep chunk_name)); + +/* Handle the transformations for reading and writing */ +PNG_EXTERN void png_do_read_transformations PNGARG((png_structp png_ptr)); +PNG_EXTERN void png_do_write_transformations PNGARG((png_structp png_ptr)); + +PNG_EXTERN void png_init_read_transformations PNGARG((png_structp png_ptr)); + +#ifdef PNG_PROGRESSIVE_READ_SUPPORTED +PNG_EXTERN void png_push_read_chunk PNGARG((png_structp png_ptr, + png_infop info_ptr)); +PNG_EXTERN void png_push_read_sig PNGARG((png_structp png_ptr, + png_infop info_ptr)); +PNG_EXTERN void png_push_check_crc PNGARG((png_structp png_ptr)); +PNG_EXTERN void png_push_crc_skip PNGARG((png_structp png_ptr, + png_uint_32 length)); +PNG_EXTERN void png_push_crc_finish PNGARG((png_structp png_ptr)); +PNG_EXTERN void png_push_save_buffer PNGARG((png_structp png_ptr)); +PNG_EXTERN void png_push_restore_buffer PNGARG((png_structp png_ptr, + png_bytep buffer, png_size_t buffer_length)); +PNG_EXTERN void png_push_read_IDAT PNGARG((png_structp png_ptr)); +PNG_EXTERN void png_process_IDAT_data PNGARG((png_structp png_ptr, + png_bytep buffer, png_size_t buffer_length)); +PNG_EXTERN void png_push_process_row PNGARG((png_structp png_ptr)); +PNG_EXTERN void png_push_handle_unknown PNGARG((png_structp png_ptr, + png_infop info_ptr, png_uint_32 length)); +PNG_EXTERN void png_push_have_info PNGARG((png_structp png_ptr, + png_infop info_ptr)); +PNG_EXTERN void png_push_have_end PNGARG((png_structp png_ptr, + png_infop info_ptr)); +PNG_EXTERN void png_push_have_row PNGARG((png_structp png_ptr, png_bytep row)); +PNG_EXTERN void png_push_read_end PNGARG((png_structp png_ptr, + png_infop info_ptr)); +PNG_EXTERN void png_process_some_data PNGARG((png_structp png_ptr, + png_infop info_ptr)); +PNG_EXTERN void png_read_push_finish_row PNGARG((png_structp png_ptr)); +#ifdef PNG_READ_tEXt_SUPPORTED +PNG_EXTERN void png_push_handle_tEXt PNGARG((png_structp png_ptr, + png_infop info_ptr, png_uint_32 length)); +PNG_EXTERN void png_push_read_tEXt PNGARG((png_structp png_ptr, + png_infop info_ptr)); +#endif +#ifdef PNG_READ_zTXt_SUPPORTED +PNG_EXTERN void png_push_handle_zTXt PNGARG((png_structp png_ptr, + png_infop info_ptr, png_uint_32 length)); +PNG_EXTERN void png_push_read_zTXt PNGARG((png_structp png_ptr, + png_infop info_ptr)); +#endif +#ifdef PNG_READ_iTXt_SUPPORTED +PNG_EXTERN void png_push_handle_iTXt PNGARG((png_structp png_ptr, + png_infop info_ptr, png_uint_32 length)); +PNG_EXTERN void png_push_read_iTXt PNGARG((png_structp png_ptr, + png_infop info_ptr)); +#endif + +#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */ + +#ifdef PNG_MNG_FEATURES_SUPPORTED +PNG_EXTERN void png_do_read_intrapixel PNGARG((png_row_infop row_info, + png_bytep row)); +PNG_EXTERN void png_do_write_intrapixel PNGARG((png_row_infop row_info, + png_bytep row)); +#endif + +/* Added at libpng version 1.4.0 */ +#ifdef PNG_cHRM_SUPPORTED +PNG_EXTERN int png_check_cHRM_fixed PNGARG((png_structp png_ptr, + png_fixed_point int_white_x, png_fixed_point int_white_y, + png_fixed_point int_red_x, png_fixed_point int_red_y, png_fixed_point + int_green_x, png_fixed_point int_green_y, png_fixed_point int_blue_x, + png_fixed_point int_blue_y)); +#endif + +#ifdef PNG_cHRM_SUPPORTED +#ifdef PNG_CHECK_cHRM_SUPPORTED +/* Added at libpng version 1.2.34 and 1.4.0 */ +PNG_EXTERN void png_64bit_product PNGARG((long v1, long v2, + unsigned long *hi_product, unsigned long *lo_product)); +#endif +#endif + +/* Added at libpng version 1.4.0 */ +PNG_EXTERN void png_check_IHDR PNGARG((png_structp png_ptr, + png_uint_32 width, png_uint_32 height, int bit_depth, + int color_type, int interlace_type, int compression_type, + int filter_type)); + +/* Free all memory used by the read (old method - NOT DLL EXPORTED) */ +PNG_EXTERN void png_read_destroy PNGARG((png_structp png_ptr, png_infop info_ptr, + png_infop end_info_ptr)); + +/* Free any memory used in png_ptr struct (old method - NOT DLL EXPORTED) */ +PNG_EXTERN void png_write_destroy PNGARG((png_structp png_ptr)); + +#ifdef USE_FAR_KEYWORD /* memory model conversion function */ +PNG_EXTERN void *png_far_to_near PNGARG((png_structp png_ptr,png_voidp ptr, + int check)); +#endif /* USE_FAR_KEYWORD */ + +/* Define PNG_DEBUG at compile time for debugging information. Higher + * numbers for PNG_DEBUG mean more debugging information. This has + * only been added since version 0.95 so it is not implemented throughout + * libpng yet, but more support will be added as needed. + */ +#ifdef PNG_DEBUG +#if (PNG_DEBUG > 0) +#if !defined(PNG_DEBUG_FILE) && defined(_MSC_VER) +#include +#if (PNG_DEBUG > 1) +#ifndef _DEBUG +# define _DEBUG +#endif +#ifndef png_debug +#define png_debug(l,m) _RPT0(_CRT_WARN,m PNG_STRING_NEWLINE) +#endif +#ifndef png_debug1 +#define png_debug1(l,m,p1) _RPT1(_CRT_WARN,m PNG_STRING_NEWLINE,p1) +#endif +#ifndef png_debug2 +#define png_debug2(l,m,p1,p2) _RPT2(_CRT_WARN,m PNG_STRING_NEWLINE,p1,p2) +#endif +#endif +#else /* PNG_DEBUG_FILE || !_MSC_VER */ +#ifndef PNG_DEBUG_FILE +#define PNG_DEBUG_FILE stderr +#endif /* PNG_DEBUG_FILE */ + +#if (PNG_DEBUG > 1) +/* Note: ["%s"m PNG_STRING_NEWLINE] probably does not work on + * non-ISO compilers + */ +# ifdef __STDC__ +# ifndef png_debug +# define png_debug(l,m) \ + { \ + int num_tabs=l; \ + fprintf(PNG_DEBUG_FILE,"%s"m PNG_STRING_NEWLINE,(num_tabs==1 ? "\t" : \ + (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":"")))); \ + } +# endif +# ifndef png_debug1 +# define png_debug1(l,m,p1) \ + { \ + int num_tabs=l; \ + fprintf(PNG_DEBUG_FILE,"%s"m PNG_STRING_NEWLINE,(num_tabs==1 ? "\t" : \ + (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":""))),p1); \ + } +# endif +# ifndef png_debug2 +# define png_debug2(l,m,p1,p2) \ + { \ + int num_tabs=l; \ + fprintf(PNG_DEBUG_FILE,"%s"m PNG_STRING_NEWLINE,(num_tabs==1 ? "\t" : \ + (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":""))),p1,p2); \ + } +# endif +# else /* __STDC __ */ +# ifndef png_debug +# define png_debug(l,m) \ + { \ + int num_tabs=l; \ + char format[256]; \ + snprintf(format,256,"%s%s%s",(num_tabs==1 ? "\t" : \ + (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":""))), \ + m,PNG_STRING_NEWLINE); \ + fprintf(PNG_DEBUG_FILE,format); \ + } +# endif +# ifndef png_debug1 +# define png_debug1(l,m,p1) \ + { \ + int num_tabs=l; \ + char format[256]; \ + snprintf(format,256,"%s%s%s",(num_tabs==1 ? "\t" : \ + (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":""))), \ + m,PNG_STRING_NEWLINE); \ + fprintf(PNG_DEBUG_FILE,format,p1); \ + } +# endif +# ifndef png_debug2 +# define png_debug2(l,m,p1,p2) \ + { \ + int num_tabs=l; \ + char format[256]; \ + snprintf(format,256,"%s%s%s",(num_tabs==1 ? "\t" : \ + (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":""))), \ + m,PNG_STRING_NEWLINE); \ + fprintf(PNG_DEBUG_FILE,format,p1,p2); \ + } +# endif +# endif /* __STDC __ */ +#endif /* (PNG_DEBUG > 1) */ + +#endif /* _MSC_VER */ +#endif /* (PNG_DEBUG > 0) */ +#endif /* PNG_DEBUG */ +#ifndef png_debug +#define png_debug(l, m) +#endif +#ifndef png_debug1 +#define png_debug1(l, m, p1) +#endif +#ifndef png_debug2 +#define png_debug2(l, m, p1, p2) +#endif + +/* Maintainer: Put new private prototypes here ^ and in libpngpf.3 */ + +#ifdef __cplusplus +} +#endif + +#endif /* PNG_VERSION_INFO_ONLY */ +#endif /* PNGPRIV_H */ diff --git a/libpng/pngread.c b/libpng/pngread.c new file mode 100644 index 0000000..92060d2 --- /dev/null +++ b/libpng/pngread.c @@ -0,0 +1,1361 @@ + +/* pngread.c - read a PNG file + * + * Last changed in libpng 1.4.1 [February 25, 2010] + * Copyright (c) 1998-2010 Glenn Randers-Pehrson + * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) + * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) + * + * This code is released under the libpng license. + * For conditions of distribution and use, see the disclaimer + * and license in png.h + * + * This file contains routines that an application calls directly to + * read a PNG file or stream. + */ + +#define PNG_NO_PEDANTIC_WARNINGS +#include "png.h" +#ifdef PNG_READ_SUPPORTED +#include "pngpriv.h" + + +/* Create a PNG structure for reading, and allocate any memory needed. */ +png_structp PNGAPI +png_create_read_struct(png_const_charp user_png_ver, png_voidp error_ptr, + png_error_ptr error_fn, png_error_ptr warn_fn) +{ + +#ifdef PNG_USER_MEM_SUPPORTED + return (png_create_read_struct_2(user_png_ver, error_ptr, error_fn, + warn_fn, NULL, NULL, NULL)); +} + +/* Alternate create PNG structure for reading, and allocate any memory + * needed. + */ +png_structp PNGAPI +png_create_read_struct_2(png_const_charp user_png_ver, png_voidp error_ptr, + png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr, + png_malloc_ptr malloc_fn, png_free_ptr free_fn) +{ +#endif /* PNG_USER_MEM_SUPPORTED */ + +#ifdef PNG_SETJMP_SUPPORTED + volatile +#endif + png_structp png_ptr; + volatile int png_cleanup_needed = 0; + +#ifdef PNG_SETJMP_SUPPORTED +#ifdef USE_FAR_KEYWORD + jmp_buf jmpbuf; +#endif +#endif + + int i; + + png_debug(1, "in png_create_read_struct"); + +#ifdef PNG_USER_MEM_SUPPORTED + png_ptr = (png_structp)png_create_struct_2(PNG_STRUCT_PNG, + malloc_fn, mem_ptr); +#else + png_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG); +#endif + if (png_ptr == NULL) + return (NULL); + + /* Added at libpng-1.2.6 */ +#ifdef PNG_USER_LIMITS_SUPPORTED + png_ptr->user_width_max = PNG_USER_WIDTH_MAX; + png_ptr->user_height_max = PNG_USER_HEIGHT_MAX; +# ifdef PNG_USER_CHUNK_CACHE_MAX + /* Added at libpng-1.2.43 and 1.4.0 */ + png_ptr->user_chunk_cache_max = PNG_USER_CHUNK_CACHE_MAX; +# endif +# ifdef PNG_SET_USER_CHUNK_MALLOC_MAX + /* Added at libpng-1.2.43 and 1.4.1 */ + png_ptr->user_chunk_malloc_max = PNG_USER_CHUNK_MALLOC_MAX; +# endif +#endif + +#ifdef PNG_SETJMP_SUPPORTED +/* Applications that neglect to set up their own setjmp() and then + encounter a png_error() will longjmp here. Since the jmpbuf is + then meaningless we abort instead of returning. */ +#ifdef USE_FAR_KEYWORD + if (setjmp(jmpbuf)) +#else + if (setjmp(png_jmpbuf(png_ptr))) /* Sets longjmp to match setjmp */ +#endif + PNG_ABORT(); +#ifdef USE_FAR_KEYWORD + png_memcpy(png_jmpbuf(png_ptr), jmpbuf, png_sizeof(jmp_buf)); +#endif +#endif /* PNG_SETJMP_SUPPORTED */ + +#ifdef PNG_USER_MEM_SUPPORTED + png_set_mem_fn(png_ptr, mem_ptr, malloc_fn, free_fn); +#endif + + png_set_error_fn(png_ptr, error_ptr, error_fn, warn_fn); + + if (user_png_ver) + { + i = 0; + do + { + if (user_png_ver[i] != png_libpng_ver[i]) + png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH; + } while (png_libpng_ver[i++]); + } + else + png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH; + + + if (png_ptr->flags & PNG_FLAG_LIBRARY_MISMATCH) + { + /* Libpng 0.90 and later are binary incompatible with libpng 0.89, so + * we must recompile any applications that use any older library version. + * For versions after libpng 1.0, we will be compatible, so we need + * only check the first digit. + */ + if (user_png_ver == NULL || user_png_ver[0] != png_libpng_ver[0] || + (user_png_ver[0] == '1' && user_png_ver[2] != png_libpng_ver[2]) || + (user_png_ver[0] == '0' && user_png_ver[2] < '9')) + { +#ifdef PNG_STDIO_SUPPORTED + char msg[80]; + if (user_png_ver) + { + png_snprintf(msg, 80, + "Application was compiled with png.h from libpng-%.20s", + user_png_ver); + png_warning(png_ptr, msg); + } + png_snprintf(msg, 80, + "Application is running with png.c from libpng-%.20s", + png_libpng_ver); + png_warning(png_ptr, msg); +#endif +#ifdef PNG_ERROR_NUMBERS_SUPPORTED + png_ptr->flags = 0; +#endif + png_warning(png_ptr, + "Incompatible libpng version in application and library"); + + png_cleanup_needed = 1; + } + } + + if (!png_cleanup_needed) + { + /* Initialize zbuf - compression buffer */ + png_ptr->zbuf_size = PNG_ZBUF_SIZE; + png_ptr->zbuf = (png_bytep)png_malloc_warn(png_ptr, + png_ptr->zbuf_size); + if (png_ptr->zbuf == NULL) + png_cleanup_needed = 1; + } + png_ptr->zstream.zalloc = png_zalloc; + png_ptr->zstream.zfree = png_zfree; + png_ptr->zstream.opaque = (voidpf)png_ptr; + + if (!png_cleanup_needed) + { + switch (inflateInit(&png_ptr->zstream)) + { + case Z_OK: /* Do nothing */ break; + case Z_MEM_ERROR: + case Z_STREAM_ERROR: png_warning(png_ptr, "zlib memory error"); + png_cleanup_needed = 1; break; + case Z_VERSION_ERROR: png_warning(png_ptr, "zlib version error"); + png_cleanup_needed = 1; break; + default: png_warning(png_ptr, "Unknown zlib error"); + png_cleanup_needed = 1; + } + } + + if (png_cleanup_needed) + { + /* Clean up PNG structure and deallocate any memory. */ + png_free(png_ptr, png_ptr->zbuf); + png_ptr->zbuf = NULL; +#ifdef PNG_USER_MEM_SUPPORTED + png_destroy_struct_2((png_voidp)png_ptr, + (png_free_ptr)free_fn, (png_voidp)mem_ptr); +#else + png_destroy_struct((png_voidp)png_ptr); +#endif + return (NULL); + } + + png_ptr->zstream.next_out = png_ptr->zbuf; + png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size; + + png_set_read_fn(png_ptr, NULL, NULL); + + + return (png_ptr); +} + + +#ifdef PNG_SEQUENTIAL_READ_SUPPORTED +/* Read the information before the actual image data. This has been + * changed in v0.90 to allow reading a file that already has the magic + * bytes read from the stream. You can tell libpng how many bytes have + * been read from the beginning of the stream (up to the maximum of 8) + * via png_set_sig_bytes(), and we will only check the remaining bytes + * here. The application can then have access to the signature bytes we + * read if it is determined that this isn't a valid PNG file. + */ +void PNGAPI +png_read_info(png_structp png_ptr, png_infop info_ptr) +{ + png_debug(1, "in png_read_info"); + + if (png_ptr == NULL || info_ptr == NULL) + return; + + /* If we haven't checked all of the PNG signature bytes, do so now. */ + if (png_ptr->sig_bytes < 8) + { + png_size_t num_checked = png_ptr->sig_bytes, + num_to_check = 8 - num_checked; + +#ifdef PNG_IO_STATE_SUPPORTED + png_ptr->io_state = PNG_IO_READING | PNG_IO_SIGNATURE; +#endif + + png_read_data(png_ptr, &(info_ptr->signature[num_checked]), num_to_check); + png_ptr->sig_bytes = 8; + + if (png_sig_cmp(info_ptr->signature, num_checked, num_to_check)) + { + if (num_checked < 4 && + png_sig_cmp(info_ptr->signature, num_checked, num_to_check - 4)) + png_error(png_ptr, "Not a PNG file"); + else + png_error(png_ptr, "PNG file corrupted by ASCII conversion"); + } + if (num_checked < 3) + png_ptr->mode |= PNG_HAVE_PNG_SIGNATURE; + } + + for (;;) + { + PNG_IHDR; + PNG_IDAT; + PNG_IEND; + PNG_PLTE; +#ifdef PNG_READ_bKGD_SUPPORTED + PNG_bKGD; +#endif +#ifdef PNG_READ_cHRM_SUPPORTED + PNG_cHRM; +#endif +#ifdef PNG_READ_gAMA_SUPPORTED + PNG_gAMA; +#endif +#ifdef PNG_READ_hIST_SUPPORTED + PNG_hIST; +#endif +#ifdef PNG_READ_iCCP_SUPPORTED + PNG_iCCP; +#endif +#ifdef PNG_READ_iTXt_SUPPORTED + PNG_iTXt; +#endif +#ifdef PNG_READ_oFFs_SUPPORTED + PNG_oFFs; +#endif +#ifdef PNG_READ_pCAL_SUPPORTED + PNG_pCAL; +#endif +#ifdef PNG_READ_pHYs_SUPPORTED + PNG_pHYs; +#endif +#ifdef PNG_READ_sBIT_SUPPORTED + PNG_sBIT; +#endif +#ifdef PNG_READ_sCAL_SUPPORTED + PNG_sCAL; +#endif +#ifdef PNG_READ_sPLT_SUPPORTED + PNG_sPLT; +#endif +#ifdef PNG_READ_sRGB_SUPPORTED + PNG_sRGB; +#endif +#ifdef PNG_READ_tEXt_SUPPORTED + PNG_tEXt; +#endif +#ifdef PNG_READ_tIME_SUPPORTED + PNG_tIME; +#endif +#ifdef PNG_READ_tRNS_SUPPORTED + PNG_tRNS; +#endif +#ifdef PNG_READ_zTXt_SUPPORTED + PNG_zTXt; +#endif + png_uint_32 length = png_read_chunk_header(png_ptr); + PNG_CONST png_bytep chunk_name = png_ptr->chunk_name; + + /* This should be a binary subdivision search or a hash for + * matching the chunk name rather than a linear search. + */ + if (!png_memcmp(chunk_name, png_IDAT, 4)) + if (png_ptr->mode & PNG_AFTER_IDAT) + png_ptr->mode |= PNG_HAVE_CHUNK_AFTER_IDAT; + + if (!png_memcmp(chunk_name, png_IHDR, 4)) + png_handle_IHDR(png_ptr, info_ptr, length); + else if (!png_memcmp(chunk_name, png_IEND, 4)) + png_handle_IEND(png_ptr, info_ptr, length); +#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED + else if (png_handle_as_unknown(png_ptr, chunk_name)) + { + if (!png_memcmp(chunk_name, png_IDAT, 4)) + png_ptr->mode |= PNG_HAVE_IDAT; + png_handle_unknown(png_ptr, info_ptr, length); + if (!png_memcmp(chunk_name, png_PLTE, 4)) + png_ptr->mode |= PNG_HAVE_PLTE; + else if (!png_memcmp(chunk_name, png_IDAT, 4)) + { + if (!(png_ptr->mode & PNG_HAVE_IHDR)) + png_error(png_ptr, "Missing IHDR before IDAT"); + else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE && + !(png_ptr->mode & PNG_HAVE_PLTE)) + png_error(png_ptr, "Missing PLTE before IDAT"); + break; + } + } +#endif + else if (!png_memcmp(chunk_name, png_PLTE, 4)) + png_handle_PLTE(png_ptr, info_ptr, length); + else if (!png_memcmp(chunk_name, png_IDAT, 4)) + { + if (!(png_ptr->mode & PNG_HAVE_IHDR)) + png_error(png_ptr, "Missing IHDR before IDAT"); + else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE && + !(png_ptr->mode & PNG_HAVE_PLTE)) + png_error(png_ptr, "Missing PLTE before IDAT"); + + png_ptr->idat_size = length; + png_ptr->mode |= PNG_HAVE_IDAT; + break; + } +#ifdef PNG_READ_bKGD_SUPPORTED + else if (!png_memcmp(chunk_name, png_bKGD, 4)) + png_handle_bKGD(png_ptr, info_ptr, length); +#endif +#ifdef PNG_READ_cHRM_SUPPORTED + else if (!png_memcmp(chunk_name, png_cHRM, 4)) + png_handle_cHRM(png_ptr, info_ptr, length); +#endif +#ifdef PNG_READ_gAMA_SUPPORTED + else if (!png_memcmp(chunk_name, png_gAMA, 4)) + png_handle_gAMA(png_ptr, info_ptr, length); +#endif +#ifdef PNG_READ_hIST_SUPPORTED + else if (!png_memcmp(chunk_name, png_hIST, 4)) + png_handle_hIST(png_ptr, info_ptr, length); +#endif +#ifdef PNG_READ_oFFs_SUPPORTED + else if (!png_memcmp(chunk_name, png_oFFs, 4)) + png_handle_oFFs(png_ptr, info_ptr, length); +#endif +#ifdef PNG_READ_pCAL_SUPPORTED + else if (!png_memcmp(chunk_name, png_pCAL, 4)) + png_handle_pCAL(png_ptr, info_ptr, length); +#endif +#ifdef PNG_READ_sCAL_SUPPORTED + else if (!png_memcmp(chunk_name, png_sCAL, 4)) + png_handle_sCAL(png_ptr, info_ptr, length); +#endif +#ifdef PNG_READ_pHYs_SUPPORTED + else if (!png_memcmp(chunk_name, png_pHYs, 4)) + png_handle_pHYs(png_ptr, info_ptr, length); +#endif +#ifdef PNG_READ_sBIT_SUPPORTED + else if (!png_memcmp(chunk_name, png_sBIT, 4)) + png_handle_sBIT(png_ptr, info_ptr, length); +#endif +#ifdef PNG_READ_sRGB_SUPPORTED + else if (!png_memcmp(chunk_name, png_sRGB, 4)) + png_handle_sRGB(png_ptr, info_ptr, length); +#endif +#ifdef PNG_READ_iCCP_SUPPORTED + else if (!png_memcmp(chunk_name, png_iCCP, 4)) + png_handle_iCCP(png_ptr, info_ptr, length); +#endif +#ifdef PNG_READ_sPLT_SUPPORTED + else if (!png_memcmp(chunk_name, png_sPLT, 4)) + png_handle_sPLT(png_ptr, info_ptr, length); +#endif +#ifdef PNG_READ_tEXt_SUPPORTED + else if (!png_memcmp(chunk_name, png_tEXt, 4)) + png_handle_tEXt(png_ptr, info_ptr, length); +#endif +#ifdef PNG_READ_tIME_SUPPORTED + else if (!png_memcmp(chunk_name, png_tIME, 4)) + png_handle_tIME(png_ptr, info_ptr, length); +#endif +#ifdef PNG_READ_tRNS_SUPPORTED + else if (!png_memcmp(chunk_name, png_tRNS, 4)) + png_handle_tRNS(png_ptr, info_ptr, length); +#endif +#ifdef PNG_READ_zTXt_SUPPORTED + else if (!png_memcmp(chunk_name, png_zTXt, 4)) + png_handle_zTXt(png_ptr, info_ptr, length); +#endif +#ifdef PNG_READ_iTXt_SUPPORTED + else if (!png_memcmp(chunk_name, png_iTXt, 4)) + png_handle_iTXt(png_ptr, info_ptr, length); +#endif + else + png_handle_unknown(png_ptr, info_ptr, length); + } +} +#endif /* PNG_SEQUENTIAL_READ_SUPPORTED */ + +/* Optional call to update the users info_ptr structure */ +void PNGAPI +png_read_update_info(png_structp png_ptr, png_infop info_ptr) +{ + png_debug(1, "in png_read_update_info"); + + if (png_ptr == NULL) + return; + if (!(png_ptr->flags & PNG_FLAG_ROW_INIT)) + png_read_start_row(png_ptr); + else + png_warning(png_ptr, + "Ignoring extra png_read_update_info() call; row buffer not reallocated"); + + png_read_transform_info(png_ptr, info_ptr); +} + +#ifdef PNG_SEQUENTIAL_READ_SUPPORTED +/* Initialize palette, background, etc, after transformations + * are set, but before any reading takes place. This allows + * the user to obtain a gamma-corrected palette, for example. + * If the user doesn't call this, we will do it ourselves. + */ +void PNGAPI +png_start_read_image(png_structp png_ptr) +{ + png_debug(1, "in png_start_read_image"); + + if (png_ptr == NULL) + return; + if (!(png_ptr->flags & PNG_FLAG_ROW_INIT)) + png_read_start_row(png_ptr); +} +#endif /* PNG_SEQUENTIAL_READ_SUPPORTED */ + +#ifdef PNG_SEQUENTIAL_READ_SUPPORTED +void PNGAPI +png_read_row(png_structp png_ptr, png_bytep row, png_bytep dsp_row) +{ + PNG_IDAT; + PNG_CONST int png_pass_dsp_mask[7] = {0xff, 0x0f, 0xff, 0x33, 0xff, 0x55, + 0xff}; + PNG_CONST int png_pass_mask[7] = {0x80, 0x08, 0x88, 0x22, 0xaa, 0x55, 0xff}; + int ret; + + if (png_ptr == NULL) + return; + + png_debug2(1, "in png_read_row (row %lu, pass %d)", + (unsigned long) png_ptr->row_number, png_ptr->pass); + + if (!(png_ptr->flags & PNG_FLAG_ROW_INIT)) + png_read_start_row(png_ptr); + if (png_ptr->row_number == 0 && png_ptr->pass == 0) + { + /* Check for transforms that have been set but were defined out */ +#if defined(PNG_WRITE_INVERT_SUPPORTED) && !defined(PNG_READ_INVERT_SUPPORTED) + if (png_ptr->transformations & PNG_INVERT_MONO) + png_warning(png_ptr, "PNG_READ_INVERT_SUPPORTED is not defined"); +#endif +#if defined(PNG_WRITE_FILLER_SUPPORTED) && !defined(PNG_READ_FILLER_SUPPORTED) + if (png_ptr->transformations & PNG_FILLER) + png_warning(png_ptr, "PNG_READ_FILLER_SUPPORTED is not defined"); +#endif +#if defined(PNG_WRITE_PACKSWAP_SUPPORTED) && \ + !defined(PNG_READ_PACKSWAP_SUPPORTED) + if (png_ptr->transformations & PNG_PACKSWAP) + png_warning(png_ptr, "PNG_READ_PACKSWAP_SUPPORTED is not defined"); +#endif +#if defined(PNG_WRITE_PACK_SUPPORTED) && !defined(PNG_READ_PACK_SUPPORTED) + if (png_ptr->transformations & PNG_PACK) + png_warning(png_ptr, "PNG_READ_PACK_SUPPORTED is not defined"); +#endif +#if defined(PNG_WRITE_SHIFT_SUPPORTED) && !defined(PNG_READ_SHIFT_SUPPORTED) + if (png_ptr->transformations & PNG_SHIFT) + png_warning(png_ptr, "PNG_READ_SHIFT_SUPPORTED is not defined"); +#endif +#if defined(PNG_WRITE_BGR_SUPPORTED) && !defined(PNG_READ_BGR_SUPPORTED) + if (png_ptr->transformations & PNG_BGR) + png_warning(png_ptr, "PNG_READ_BGR_SUPPORTED is not defined"); +#endif +#if defined(PNG_WRITE_SWAP_SUPPORTED) && !defined(PNG_READ_SWAP_SUPPORTED) + if (png_ptr->transformations & PNG_SWAP_BYTES) + png_warning(png_ptr, "PNG_READ_SWAP_SUPPORTED is not defined"); +#endif + } + +#ifdef PNG_READ_INTERLACING_SUPPORTED + /* If interlaced and we do not need a new row, combine row and return */ + if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE)) + { + switch (png_ptr->pass) + { + case 0: + if (png_ptr->row_number & 0x07) + { + if (dsp_row != NULL) + png_combine_row(png_ptr, dsp_row, + png_pass_dsp_mask[png_ptr->pass]); + png_read_finish_row(png_ptr); + return; + } + break; + case 1: + if ((png_ptr->row_number & 0x07) || png_ptr->width < 5) + { + if (dsp_row != NULL) + png_combine_row(png_ptr, dsp_row, + png_pass_dsp_mask[png_ptr->pass]); + png_read_finish_row(png_ptr); + return; + } + break; + case 2: + if ((png_ptr->row_number & 0x07) != 4) + { + if (dsp_row != NULL && (png_ptr->row_number & 4)) + png_combine_row(png_ptr, dsp_row, + png_pass_dsp_mask[png_ptr->pass]); + png_read_finish_row(png_ptr); + return; + } + break; + case 3: + if ((png_ptr->row_number & 3) || png_ptr->width < 3) + { + if (dsp_row != NULL) + png_combine_row(png_ptr, dsp_row, + png_pass_dsp_mask[png_ptr->pass]); + png_read_finish_row(png_ptr); + return; + } + break; + case 4: + if ((png_ptr->row_number & 3) != 2) + { + if (dsp_row != NULL && (png_ptr->row_number & 2)) + png_combine_row(png_ptr, dsp_row, + png_pass_dsp_mask[png_ptr->pass]); + png_read_finish_row(png_ptr); + return; + } + break; + case 5: + if ((png_ptr->row_number & 1) || png_ptr->width < 2) + { + if (dsp_row != NULL) + png_combine_row(png_ptr, dsp_row, + png_pass_dsp_mask[png_ptr->pass]); + png_read_finish_row(png_ptr); + return; + } + break; + case 6: + if (!(png_ptr->row_number & 1)) + { + png_read_finish_row(png_ptr); + return; + } + break; + } + } +#endif + + if (!(png_ptr->mode & PNG_HAVE_IDAT)) + png_error(png_ptr, "Invalid attempt to read row data"); + + png_ptr->zstream.next_out = png_ptr->row_buf; + png_ptr->zstream.avail_out = + (uInt)(PNG_ROWBYTES(png_ptr->pixel_depth, + png_ptr->iwidth) + 1); + do + { + if (!(png_ptr->zstream.avail_in)) + { + while (!png_ptr->idat_size) + { + png_crc_finish(png_ptr, 0); + + png_ptr->idat_size = png_read_chunk_header(png_ptr); + if (png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) + png_error(png_ptr, "Not enough image data"); + } + png_ptr->zstream.avail_in = (uInt)png_ptr->zbuf_size; + png_ptr->zstream.next_in = png_ptr->zbuf; + if (png_ptr->zbuf_size > png_ptr->idat_size) + png_ptr->zstream.avail_in = (uInt)png_ptr->idat_size; + png_crc_read(png_ptr, png_ptr->zbuf, + (png_size_t)png_ptr->zstream.avail_in); + png_ptr->idat_size -= png_ptr->zstream.avail_in; + } + ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH); + if (ret == Z_STREAM_END) + { + if (png_ptr->zstream.avail_out || png_ptr->zstream.avail_in || + png_ptr->idat_size) + png_benign_error(png_ptr, "Extra compressed data"); + png_ptr->mode |= PNG_AFTER_IDAT; + png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED; + break; + } + if (ret != Z_OK) + png_error(png_ptr, png_ptr->zstream.msg ? png_ptr->zstream.msg : + "Decompression error"); + + } while (png_ptr->zstream.avail_out); + + png_ptr->row_info.color_type = png_ptr->color_type; + png_ptr->row_info.width = png_ptr->iwidth; + png_ptr->row_info.channels = png_ptr->channels; + png_ptr->row_info.bit_depth = png_ptr->bit_depth; + png_ptr->row_info.pixel_depth = png_ptr->pixel_depth; + png_ptr->row_info.rowbytes = PNG_ROWBYTES(png_ptr->row_info.pixel_depth, + png_ptr->row_info.width); + + if (png_ptr->row_buf[0]) + png_read_filter_row(png_ptr, &(png_ptr->row_info), + png_ptr->row_buf + 1, png_ptr->prev_row + 1, + (int)(png_ptr->row_buf[0])); + + png_memcpy(png_ptr->prev_row, png_ptr->row_buf, png_ptr->rowbytes + 1); + +#ifdef PNG_MNG_FEATURES_SUPPORTED + if ((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) && + (png_ptr->filter_type == PNG_INTRAPIXEL_DIFFERENCING)) + { + /* Intrapixel differencing */ + png_do_read_intrapixel(&(png_ptr->row_info), png_ptr->row_buf + 1); + } +#endif + + + if (png_ptr->transformations || (png_ptr->flags&PNG_FLAG_STRIP_ALPHA)) + png_do_read_transformations(png_ptr); + +#ifdef PNG_READ_INTERLACING_SUPPORTED + /* Blow up interlaced rows to full size */ + if (png_ptr->interlaced && + (png_ptr->transformations & PNG_INTERLACE)) + { + if (png_ptr->pass < 6) + /* Old interface (pre-1.0.9): + * png_do_read_interlace(&(png_ptr->row_info), + * png_ptr->row_buf + 1, png_ptr->pass, png_ptr->transformations); + */ + png_do_read_interlace(png_ptr); + + if (dsp_row != NULL) + png_combine_row(png_ptr, dsp_row, + png_pass_dsp_mask[png_ptr->pass]); + if (row != NULL) + png_combine_row(png_ptr, row, + png_pass_mask[png_ptr->pass]); + } + else +#endif + { + if (row != NULL) + png_combine_row(png_ptr, row, 0xff); + if (dsp_row != NULL) + png_combine_row(png_ptr, dsp_row, 0xff); + } + png_read_finish_row(png_ptr); + + if (png_ptr->read_row_fn != NULL) + (*(png_ptr->read_row_fn))(png_ptr, png_ptr->row_number, png_ptr->pass); +} +#endif /* PNG_SEQUENTIAL_READ_SUPPORTED */ + +#ifdef PNG_SEQUENTIAL_READ_SUPPORTED +/* Read one or more rows of image data. If the image is interlaced, + * and png_set_interlace_handling() has been called, the rows need to + * contain the contents of the rows from the previous pass. If the + * image has alpha or transparency, and png_handle_alpha()[*] has been + * called, the rows contents must be initialized to the contents of the + * screen. + * + * "row" holds the actual image, and pixels are placed in it + * as they arrive. If the image is displayed after each pass, it will + * appear to "sparkle" in. "display_row" can be used to display a + * "chunky" progressive image, with finer detail added as it becomes + * available. If you do not want this "chunky" display, you may pass + * NULL for display_row. If you do not want the sparkle display, and + * you have not called png_handle_alpha(), you may pass NULL for rows. + * If you have called png_handle_alpha(), and the image has either an + * alpha channel or a transparency chunk, you must provide a buffer for + * rows. In this case, you do not have to provide a display_row buffer + * also, but you may. If the image is not interlaced, or if you have + * not called png_set_interlace_handling(), the display_row buffer will + * be ignored, so pass NULL to it. + * + * [*] png_handle_alpha() does not exist yet, as of this version of libpng + */ + +void PNGAPI +png_read_rows(png_structp png_ptr, png_bytepp row, + png_bytepp display_row, png_uint_32 num_rows) +{ + png_uint_32 i; + png_bytepp rp; + png_bytepp dp; + + png_debug(1, "in png_read_rows"); + + if (png_ptr == NULL) + return; + rp = row; + dp = display_row; + if (rp != NULL && dp != NULL) + for (i = 0; i < num_rows; i++) + { + png_bytep rptr = *rp++; + png_bytep dptr = *dp++; + + png_read_row(png_ptr, rptr, dptr); + } + else if (rp != NULL) + for (i = 0; i < num_rows; i++) + { + png_bytep rptr = *rp; + png_read_row(png_ptr, rptr, NULL); + rp++; + } + else if (dp != NULL) + for (i = 0; i < num_rows; i++) + { + png_bytep dptr = *dp; + png_read_row(png_ptr, NULL, dptr); + dp++; + } +} +#endif /* PNG_SEQUENTIAL_READ_SUPPORTED */ + +#ifdef PNG_SEQUENTIAL_READ_SUPPORTED +/* Read the entire image. If the image has an alpha channel or a tRNS + * chunk, and you have called png_handle_alpha()[*], you will need to + * initialize the image to the current image that PNG will be overlaying. + * We set the num_rows again here, in case it was incorrectly set in + * png_read_start_row() by a call to png_read_update_info() or + * png_start_read_image() if png_set_interlace_handling() wasn't called + * prior to either of these functions like it should have been. You can + * only call this function once. If you desire to have an image for + * each pass of a interlaced image, use png_read_rows() instead. + * + * [*] png_handle_alpha() does not exist yet, as of this version of libpng + */ +void PNGAPI +png_read_image(png_structp png_ptr, png_bytepp image) +{ + png_uint_32 i, image_height; + int pass, j; + png_bytepp rp; + + png_debug(1, "in png_read_image"); + + if (png_ptr == NULL) + return; + +#ifdef PNG_READ_INTERLACING_SUPPORTED + pass = png_set_interlace_handling(png_ptr); +#else + if (png_ptr->interlaced) + png_error(png_ptr, + "Cannot read interlaced image -- interlace handler disabled"); + pass = 1; +#endif + + + image_height=png_ptr->height; + png_ptr->num_rows = image_height; /* Make sure this is set correctly */ + + for (j = 0; j < pass; j++) + { + rp = image; + for (i = 0; i < image_height; i++) + { + png_read_row(png_ptr, *rp, NULL); + rp++; + } + } +} +#endif /* PNG_SEQUENTIAL_READ_SUPPORTED */ + +#ifdef PNG_SEQUENTIAL_READ_SUPPORTED +/* Read the end of the PNG file. Will not read past the end of the + * file, will verify the end is accurate, and will read any comments + * or time information at the end of the file, if info is not NULL. + */ +void PNGAPI +png_read_end(png_structp png_ptr, png_infop info_ptr) +{ + png_debug(1, "in png_read_end"); + + if (png_ptr == NULL) + return; + png_crc_finish(png_ptr, 0); /* Finish off CRC from last IDAT chunk */ + + do + { + PNG_IHDR; + PNG_IDAT; + PNG_IEND; + PNG_PLTE; +#ifdef PNG_READ_bKGD_SUPPORTED + PNG_bKGD; +#endif +#ifdef PNG_READ_cHRM_SUPPORTED + PNG_cHRM; +#endif +#ifdef PNG_READ_gAMA_SUPPORTED + PNG_gAMA; +#endif +#ifdef PNG_READ_hIST_SUPPORTED + PNG_hIST; +#endif +#ifdef PNG_READ_iCCP_SUPPORTED + PNG_iCCP; +#endif +#ifdef PNG_READ_iTXt_SUPPORTED + PNG_iTXt; +#endif +#ifdef PNG_READ_oFFs_SUPPORTED + PNG_oFFs; +#endif +#ifdef PNG_READ_pCAL_SUPPORTED + PNG_pCAL; +#endif +#ifdef PNG_READ_pHYs_SUPPORTED + PNG_pHYs; +#endif +#ifdef PNG_READ_sBIT_SUPPORTED + PNG_sBIT; +#endif +#ifdef PNG_READ_sCAL_SUPPORTED + PNG_sCAL; +#endif +#ifdef PNG_READ_sPLT_SUPPORTED + PNG_sPLT; +#endif +#ifdef PNG_READ_sRGB_SUPPORTED + PNG_sRGB; +#endif +#ifdef PNG_READ_tEXt_SUPPORTED + PNG_tEXt; +#endif +#ifdef PNG_READ_tIME_SUPPORTED + PNG_tIME; +#endif +#ifdef PNG_READ_tRNS_SUPPORTED + PNG_tRNS; +#endif +#ifdef PNG_READ_zTXt_SUPPORTED + PNG_zTXt; +#endif + png_uint_32 length = png_read_chunk_header(png_ptr); + PNG_CONST png_bytep chunk_name = png_ptr->chunk_name; + + if (!png_memcmp(chunk_name, png_IHDR, 4)) + png_handle_IHDR(png_ptr, info_ptr, length); + else if (!png_memcmp(chunk_name, png_IEND, 4)) + png_handle_IEND(png_ptr, info_ptr, length); +#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED + else if (png_handle_as_unknown(png_ptr, chunk_name)) + { + if (!png_memcmp(chunk_name, png_IDAT, 4)) + { + if ((length > 0) || (png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT)) + png_benign_error(png_ptr, "Too many IDATs found"); + } + png_handle_unknown(png_ptr, info_ptr, length); + if (!png_memcmp(chunk_name, png_PLTE, 4)) + png_ptr->mode |= PNG_HAVE_PLTE; + } +#endif + else if (!png_memcmp(chunk_name, png_IDAT, 4)) + { + /* Zero length IDATs are legal after the last IDAT has been + * read, but not after other chunks have been read. + */ + if ((length > 0) || (png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT)) + png_benign_error(png_ptr, "Too many IDATs found"); + png_crc_finish(png_ptr, length); + } + else if (!png_memcmp(chunk_name, png_PLTE, 4)) + png_handle_PLTE(png_ptr, info_ptr, length); +#ifdef PNG_READ_bKGD_SUPPORTED + else if (!png_memcmp(chunk_name, png_bKGD, 4)) + png_handle_bKGD(png_ptr, info_ptr, length); +#endif +#ifdef PNG_READ_cHRM_SUPPORTED + else if (!png_memcmp(chunk_name, png_cHRM, 4)) + png_handle_cHRM(png_ptr, info_ptr, length); +#endif +#ifdef PNG_READ_gAMA_SUPPORTED + else if (!png_memcmp(chunk_name, png_gAMA, 4)) + png_handle_gAMA(png_ptr, info_ptr, length); +#endif +#ifdef PNG_READ_hIST_SUPPORTED + else if (!png_memcmp(chunk_name, png_hIST, 4)) + png_handle_hIST(png_ptr, info_ptr, length); +#endif +#ifdef PNG_READ_oFFs_SUPPORTED + else if (!png_memcmp(chunk_name, png_oFFs, 4)) + png_handle_oFFs(png_ptr, info_ptr, length); +#endif +#ifdef PNG_READ_pCAL_SUPPORTED + else if (!png_memcmp(chunk_name, png_pCAL, 4)) + png_handle_pCAL(png_ptr, info_ptr, length); +#endif +#ifdef PNG_READ_sCAL_SUPPORTED + else if (!png_memcmp(chunk_name, png_sCAL, 4)) + png_handle_sCAL(png_ptr, info_ptr, length); +#endif +#ifdef PNG_READ_pHYs_SUPPORTED + else if (!png_memcmp(chunk_name, png_pHYs, 4)) + png_handle_pHYs(png_ptr, info_ptr, length); +#endif +#ifdef PNG_READ_sBIT_SUPPORTED + else if (!png_memcmp(chunk_name, png_sBIT, 4)) + png_handle_sBIT(png_ptr, info_ptr, length); +#endif +#ifdef PNG_READ_sRGB_SUPPORTED + else if (!png_memcmp(chunk_name, png_sRGB, 4)) + png_handle_sRGB(png_ptr, info_ptr, length); +#endif +#ifdef PNG_READ_iCCP_SUPPORTED + else if (!png_memcmp(chunk_name, png_iCCP, 4)) + png_handle_iCCP(png_ptr, info_ptr, length); +#endif +#ifdef PNG_READ_sPLT_SUPPORTED + else if (!png_memcmp(chunk_name, png_sPLT, 4)) + png_handle_sPLT(png_ptr, info_ptr, length); +#endif +#ifdef PNG_READ_tEXt_SUPPORTED + else if (!png_memcmp(chunk_name, png_tEXt, 4)) + png_handle_tEXt(png_ptr, info_ptr, length); +#endif +#ifdef PNG_READ_tIME_SUPPORTED + else if (!png_memcmp(chunk_name, png_tIME, 4)) + png_handle_tIME(png_ptr, info_ptr, length); +#endif +#ifdef PNG_READ_tRNS_SUPPORTED + else if (!png_memcmp(chunk_name, png_tRNS, 4)) + png_handle_tRNS(png_ptr, info_ptr, length); +#endif +#ifdef PNG_READ_zTXt_SUPPORTED + else if (!png_memcmp(chunk_name, png_zTXt, 4)) + png_handle_zTXt(png_ptr, info_ptr, length); +#endif +#ifdef PNG_READ_iTXt_SUPPORTED + else if (!png_memcmp(chunk_name, png_iTXt, 4)) + png_handle_iTXt(png_ptr, info_ptr, length); +#endif + else + png_handle_unknown(png_ptr, info_ptr, length); + } while (!(png_ptr->mode & PNG_HAVE_IEND)); +} +#endif /* PNG_SEQUENTIAL_READ_SUPPORTED */ + +/* Free all memory used by the read */ +void PNGAPI +png_destroy_read_struct(png_structpp png_ptr_ptr, png_infopp info_ptr_ptr, + png_infopp end_info_ptr_ptr) +{ + png_structp png_ptr = NULL; + png_infop info_ptr = NULL, end_info_ptr = NULL; +#ifdef PNG_USER_MEM_SUPPORTED + png_free_ptr free_fn = NULL; + png_voidp mem_ptr = NULL; +#endif + + png_debug(1, "in png_destroy_read_struct"); + + if (png_ptr_ptr != NULL) + png_ptr = *png_ptr_ptr; + if (png_ptr == NULL) + return; + +#ifdef PNG_USER_MEM_SUPPORTED + free_fn = png_ptr->free_fn; + mem_ptr = png_ptr->mem_ptr; +#endif + + if (info_ptr_ptr != NULL) + info_ptr = *info_ptr_ptr; + + if (end_info_ptr_ptr != NULL) + end_info_ptr = *end_info_ptr_ptr; + + png_read_destroy(png_ptr, info_ptr, end_info_ptr); + + if (info_ptr != NULL) + { +#ifdef PNG_TEXT_SUPPORTED + png_free_data(png_ptr, info_ptr, PNG_FREE_TEXT, -1); +#endif + +#ifdef PNG_USER_MEM_SUPPORTED + png_destroy_struct_2((png_voidp)info_ptr, (png_free_ptr)free_fn, + (png_voidp)mem_ptr); +#else + png_destroy_struct((png_voidp)info_ptr); +#endif + *info_ptr_ptr = NULL; + } + + if (end_info_ptr != NULL) + { +#ifdef PNG_READ_TEXT_SUPPORTED + png_free_data(png_ptr, end_info_ptr, PNG_FREE_TEXT, -1); +#endif +#ifdef PNG_USER_MEM_SUPPORTED + png_destroy_struct_2((png_voidp)end_info_ptr, (png_free_ptr)free_fn, + (png_voidp)mem_ptr); +#else + png_destroy_struct((png_voidp)end_info_ptr); +#endif + *end_info_ptr_ptr = NULL; + } + + if (png_ptr != NULL) + { +#ifdef PNG_USER_MEM_SUPPORTED + png_destroy_struct_2((png_voidp)png_ptr, (png_free_ptr)free_fn, + (png_voidp)mem_ptr); +#else + png_destroy_struct((png_voidp)png_ptr); +#endif + *png_ptr_ptr = NULL; + } +} + +/* Free all memory used by the read (old method) */ +void /* PRIVATE */ +png_read_destroy(png_structp png_ptr, png_infop info_ptr, + png_infop end_info_ptr) +{ +#ifdef PNG_SETJMP_SUPPORTED + jmp_buf tmp_jmp; +#endif + png_error_ptr error_fn; + png_error_ptr warning_fn; + png_voidp error_ptr; +#ifdef PNG_USER_MEM_SUPPORTED + png_free_ptr free_fn; +#endif + + png_debug(1, "in png_read_destroy"); + + if (info_ptr != NULL) + png_info_destroy(png_ptr, info_ptr); + + if (end_info_ptr != NULL) + png_info_destroy(png_ptr, end_info_ptr); + + png_free(png_ptr, png_ptr->zbuf); + png_free(png_ptr, png_ptr->big_row_buf); + png_free(png_ptr, png_ptr->prev_row); + png_free(png_ptr, png_ptr->chunkdata); +#ifdef PNG_READ_QUANTIZE_SUPPORTED + png_free(png_ptr, png_ptr->palette_lookup); + png_free(png_ptr, png_ptr->quantize_index); +#endif +#ifdef PNG_READ_GAMMA_SUPPORTED + png_free(png_ptr, png_ptr->gamma_table); +#endif +#ifdef PNG_READ_BACKGROUND_SUPPORTED + png_free(png_ptr, png_ptr->gamma_from_1); + png_free(png_ptr, png_ptr->gamma_to_1); +#endif + if (png_ptr->free_me & PNG_FREE_PLTE) + png_zfree(png_ptr, png_ptr->palette); + png_ptr->free_me &= ~PNG_FREE_PLTE; +#if defined(PNG_tRNS_SUPPORTED) || \ + defined(PNG_READ_EXPAND_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) + if (png_ptr->free_me & PNG_FREE_TRNS) + png_free(png_ptr, png_ptr->trans_alpha); + png_ptr->free_me &= ~PNG_FREE_TRNS; +#endif +#ifdef PNG_READ_hIST_SUPPORTED + if (png_ptr->free_me & PNG_FREE_HIST) + png_free(png_ptr, png_ptr->hist); + png_ptr->free_me &= ~PNG_FREE_HIST; +#endif +#ifdef PNG_READ_GAMMA_SUPPORTED + if (png_ptr->gamma_16_table != NULL) + { + int i; + int istop = (1 << (8 - png_ptr->gamma_shift)); + for (i = 0; i < istop; i++) + { + png_free(png_ptr, png_ptr->gamma_16_table[i]); + } + png_free(png_ptr, png_ptr->gamma_16_table); + } +#ifdef PNG_READ_BACKGROUND_SUPPORTED + if (png_ptr->gamma_16_from_1 != NULL) + { + int i; + int istop = (1 << (8 - png_ptr->gamma_shift)); + for (i = 0; i < istop; i++) + { + png_free(png_ptr, png_ptr->gamma_16_from_1[i]); + } + png_free(png_ptr, png_ptr->gamma_16_from_1); + } + if (png_ptr->gamma_16_to_1 != NULL) + { + int i; + int istop = (1 << (8 - png_ptr->gamma_shift)); + for (i = 0; i < istop; i++) + { + png_free(png_ptr, png_ptr->gamma_16_to_1[i]); + } + png_free(png_ptr, png_ptr->gamma_16_to_1); + } +#endif +#endif +#ifdef PNG_TIME_RFC1123_SUPPORTED + png_free(png_ptr, png_ptr->time_buffer); +#endif + + inflateEnd(&png_ptr->zstream); +#ifdef PNG_PROGRESSIVE_READ_SUPPORTED + png_free(png_ptr, png_ptr->save_buffer); +#endif + +#ifdef PNG_PROGRESSIVE_READ_SUPPORTED +#ifdef PNG_TEXT_SUPPORTED + png_free(png_ptr, png_ptr->current_text); +#endif /* PNG_TEXT_SUPPORTED */ +#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */ + + /* Save the important info out of the png_struct, in case it is + * being used again. + */ +#ifdef PNG_SETJMP_SUPPORTED + png_memcpy(tmp_jmp, png_ptr->jmpbuf, png_sizeof(jmp_buf)); +#endif + + error_fn = png_ptr->error_fn; + warning_fn = png_ptr->warning_fn; + error_ptr = png_ptr->error_ptr; +#ifdef PNG_USER_MEM_SUPPORTED + free_fn = png_ptr->free_fn; +#endif + + png_memset(png_ptr, 0, png_sizeof(png_struct)); + + png_ptr->error_fn = error_fn; + png_ptr->warning_fn = warning_fn; + png_ptr->error_ptr = error_ptr; +#ifdef PNG_USER_MEM_SUPPORTED + png_ptr->free_fn = free_fn; +#endif + +#ifdef PNG_SETJMP_SUPPORTED + png_memcpy(png_ptr->jmpbuf, tmp_jmp, png_sizeof(jmp_buf)); +#endif + +} + +void PNGAPI +png_set_read_status_fn(png_structp png_ptr, png_read_status_ptr read_row_fn) +{ + if (png_ptr == NULL) + return; + png_ptr->read_row_fn = read_row_fn; +} + + +#ifdef PNG_SEQUENTIAL_READ_SUPPORTED +#ifdef PNG_INFO_IMAGE_SUPPORTED +void PNGAPI +png_read_png(png_structp png_ptr, png_infop info_ptr, + int transforms, + voidp params) +{ + int row; + + if (png_ptr == NULL) + return; + + /* png_read_info() gives us all of the information from the + * PNG file before the first IDAT (image data chunk). + */ + png_read_info(png_ptr, info_ptr); + if (info_ptr->height > PNG_UINT_32_MAX/png_sizeof(png_bytep)) + png_error(png_ptr, "Image is too high to process with png_read_png()"); + + /* -------------- image transformations start here ------------------- */ + +#ifdef PNG_READ_16_TO_8_SUPPORTED + /* Tell libpng to strip 16 bit/color files down to 8 bits per color. + */ + if (transforms & PNG_TRANSFORM_STRIP_16) + png_set_strip_16(png_ptr); +#endif + +#ifdef PNG_READ_STRIP_ALPHA_SUPPORTED + /* Strip alpha bytes from the input data without combining with + * the background (not recommended). + */ + if (transforms & PNG_TRANSFORM_STRIP_ALPHA) + png_set_strip_alpha(png_ptr); +#endif + +#if defined(PNG_READ_PACK_SUPPORTED) && !defined(PNG_READ_EXPAND_SUPPORTED) + /* Extract multiple pixels with bit depths of 1, 2, or 4 from a single + * byte into separate bytes (useful for paletted and grayscale images). + */ + if (transforms & PNG_TRANSFORM_PACKING) + png_set_packing(png_ptr); +#endif + +#ifdef PNG_READ_PACKSWAP_SUPPORTED + /* Change the order of packed pixels to least significant bit first + * (not useful if you are using png_set_packing). + */ + if (transforms & PNG_TRANSFORM_PACKSWAP) + png_set_packswap(png_ptr); +#endif + +#ifdef PNG_READ_EXPAND_SUPPORTED + /* Expand paletted colors into true RGB triplets + * Expand grayscale images to full 8 bits from 1, 2, or 4 bits/pixel + * Expand paletted or RGB images with transparency to full alpha + * channels so the data will be available as RGBA quartets. + */ + if (transforms & PNG_TRANSFORM_EXPAND) + if ((png_ptr->bit_depth < 8) || + (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) || + (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS))) + png_set_expand(png_ptr); +#endif + + /* We don't handle background color or gamma transformation or quantizing. + */ + +#ifdef PNG_READ_INVERT_SUPPORTED + /* Invert monochrome files to have 0 as white and 1 as black + */ + if (transforms & PNG_TRANSFORM_INVERT_MONO) + png_set_invert_mono(png_ptr); +#endif + +#ifdef PNG_READ_SHIFT_SUPPORTED + /* If you want to shift the pixel values from the range [0,255] or + * [0,65535] to the original [0,7] or [0,31], or whatever range the + * colors were originally in: + */ + if ((transforms & PNG_TRANSFORM_SHIFT) + && png_get_valid(png_ptr, info_ptr, PNG_INFO_sBIT)) + { + png_color_8p sig_bit; + + png_get_sBIT(png_ptr, info_ptr, &sig_bit); + png_set_shift(png_ptr, sig_bit); + } +#endif + +#ifdef PNG_READ_BGR_SUPPORTED + /* Flip the RGB pixels to BGR (or RGBA to BGRA) + */ + if (transforms & PNG_TRANSFORM_BGR) + png_set_bgr(png_ptr); +#endif + +#ifdef PNG_READ_SWAP_ALPHA_SUPPORTED + /* Swap the RGBA or GA data to ARGB or AG (or BGRA to ABGR) + */ + if (transforms & PNG_TRANSFORM_SWAP_ALPHA) + png_set_swap_alpha(png_ptr); +#endif + +#ifdef PNG_READ_SWAP_SUPPORTED + /* Swap bytes of 16 bit files to least significant byte first + */ + if (transforms & PNG_TRANSFORM_SWAP_ENDIAN) + png_set_swap(png_ptr); +#endif + +/* Added at libpng-1.2.41 */ +#ifdef PNG_READ_INVERT_ALPHA_SUPPORTED + /* Invert the alpha channel from opacity to transparency + */ + if (transforms & PNG_TRANSFORM_INVERT_ALPHA) + png_set_invert_alpha(png_ptr); +#endif + +/* Added at libpng-1.2.41 */ +#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED + /* Expand grayscale image to RGB + */ + if (transforms & PNG_TRANSFORM_GRAY_TO_RGB) + png_set_gray_to_rgb(png_ptr); +#endif + + /* We don't handle adding filler bytes */ + + /* Optional call to gamma correct and add the background to the palette + * and update info structure. REQUIRED if you are expecting libpng to + * update the palette for you (i.e., you selected such a transform above). + */ + png_read_update_info(png_ptr, info_ptr); + + /* -------------- image transformations end here ------------------- */ + + png_free_data(png_ptr, info_ptr, PNG_FREE_ROWS, 0); + if (info_ptr->row_pointers == NULL) + { + png_uint_32 iptr; + + info_ptr->row_pointers = (png_bytepp)png_malloc(png_ptr, + info_ptr->height * png_sizeof(png_bytep)); + for (iptr=0; iptrheight; iptr++) + info_ptr->row_pointers[iptr] = NULL; + + info_ptr->free_me |= PNG_FREE_ROWS; + + for (row = 0; row < (int)info_ptr->height; row++) + info_ptr->row_pointers[row] = (png_bytep)png_malloc(png_ptr, + png_get_rowbytes(png_ptr, info_ptr)); + } + + png_read_image(png_ptr, info_ptr->row_pointers); + info_ptr->valid |= PNG_INFO_IDAT; + + /* Read rest of file, and get additional chunks in info_ptr - REQUIRED */ + png_read_end(png_ptr, info_ptr); + + transforms = transforms; /* Quiet compiler warnings */ + params = params; + +} +#endif /* PNG_INFO_IMAGE_SUPPORTED */ +#endif /* PNG_SEQUENTIAL_READ_SUPPORTED */ +#endif /* PNG_READ_SUPPORTED */ diff --git a/libpng/pngrio.c b/libpng/pngrio.c new file mode 100644 index 0000000..59059ca --- /dev/null +++ b/libpng/pngrio.c @@ -0,0 +1,163 @@ + +/* pngrio.c - functions for data input + * + * Last changed in libpng 1.4.1 [February 25, 2010] + * Copyright (c) 1998-2010 Glenn Randers-Pehrson + * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) + * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) + * + * This code is released under the libpng license. + * For conditions of distribution and use, see the disclaimer + * and license in png.h + * + * This file provides a location for all input. Users who need + * special handling are expected to write a function that has the same + * arguments as this and performs a similar function, but that possibly + * has a different input method. Note that you shouldn't change this + * function, but rather write a replacement function and then make + * libpng use it at run time with png_set_read_fn(...). + */ + +#define PNG_NO_PEDANTIC_WARNINGS +#include "png.h" +#ifdef PNG_READ_SUPPORTED +#include "pngpriv.h" + +/* Read the data from whatever input you are using. The default routine + * reads from a file pointer. Note that this routine sometimes gets called + * with very small lengths, so you should implement some kind of simple + * buffering if you are using unbuffered reads. This should never be asked + * to read more then 64K on a 16 bit machine. + */ +void /* PRIVATE */ +png_read_data(png_structp png_ptr, png_bytep data, png_size_t length) +{ + png_debug1(4, "reading %d bytes", (int)length); + + if (png_ptr->read_data_fn != NULL) + (*(png_ptr->read_data_fn))(png_ptr, data, length); + else + png_error(png_ptr, "Call to NULL read function"); +} + +#ifdef PNG_STDIO_SUPPORTED +/* This is the function that does the actual reading of data. If you are + * not reading from a standard C stream, you should create a replacement + * read_data function and use it at run time with png_set_read_fn(), rather + * than changing the library. + */ +#ifndef USE_FAR_KEYWORD +void PNGAPI +png_default_read_data(png_structp png_ptr, png_bytep data, png_size_t length) +{ + png_size_t check; + + if (png_ptr == NULL) + return; + /* fread() returns 0 on error, so it is OK to store this in a png_size_t + * instead of an int, which is what fread() actually returns. + */ + check = fread(data, 1, length, (png_FILE_p)png_ptr->io_ptr); + + if (check != length) + png_error(png_ptr, "Read Error"); +} +#else +/* This is the model-independent version. Since the standard I/O library + can't handle far buffers in the medium and small models, we have to copy + the data. +*/ + +#define NEAR_BUF_SIZE 1024 +#define MIN(a,b) (a <= b ? a : b) + +static void PNGAPI +png_default_read_data(png_structp png_ptr, png_bytep data, png_size_t length) +{ + png_size_t check; + png_byte *n_data; + png_FILE_p io_ptr; + + if (png_ptr == NULL) + return; + /* Check if data really is near. If so, use usual code. */ + n_data = (png_byte *)CVT_PTR_NOCHECK(data); + io_ptr = (png_FILE_p)CVT_PTR(png_ptr->io_ptr); + if ((png_bytep)n_data == data) + { + check = fread(n_data, 1, length, io_ptr); + } + else + { + png_byte buf[NEAR_BUF_SIZE]; + png_size_t read, remaining, err; + check = 0; + remaining = length; + do + { + read = MIN(NEAR_BUF_SIZE, remaining); + err = fread(buf, 1, read, io_ptr); + png_memcpy(data, buf, read); /* copy far buffer to near buffer */ + if (err != read) + break; + else + check += err; + data += read; + remaining -= read; + } + while (remaining != 0); + } + if ((png_uint_32)check != (png_uint_32)length) + png_error(png_ptr, "read Error"); +} +#endif +#endif + +/* This function allows the application to supply a new input function + * for libpng if standard C streams aren't being used. + * + * This function takes as its arguments: + * png_ptr - pointer to a png input data structure + * io_ptr - pointer to user supplied structure containing info about + * the input functions. May be NULL. + * read_data_fn - pointer to a new input function that takes as its + * arguments a pointer to a png_struct, a pointer to + * a location where input data can be stored, and a 32-bit + * unsigned int that is the number of bytes to be read. + * To exit and output any fatal error messages the new write + * function should call png_error(png_ptr, "Error msg"). + * May be NULL, in which case libpng's default function will + * be used. + */ +void PNGAPI +png_set_read_fn(png_structp png_ptr, png_voidp io_ptr, + png_rw_ptr read_data_fn) +{ + if (png_ptr == NULL) + return; + png_ptr->io_ptr = io_ptr; + +#ifdef PNG_STDIO_SUPPORTED + if (read_data_fn != NULL) + png_ptr->read_data_fn = read_data_fn; + else + png_ptr->read_data_fn = png_default_read_data; +#else + png_ptr->read_data_fn = read_data_fn; +#endif + + /* It is an error to write to a read device */ + if (png_ptr->write_data_fn != NULL) + { + png_ptr->write_data_fn = NULL; + png_warning(png_ptr, + "It's an error to set both read_data_fn and write_data_fn in the "); + png_warning(png_ptr, + "same structure. Resetting write_data_fn to NULL"); + } + +#ifdef PNG_WRITE_FLUSH_SUPPORTED + png_ptr->output_flush_fn = NULL; +#endif +} +#endif /* PNG_READ_SUPPORTED */ diff --git a/libpng/pngrtran.c b/libpng/pngrtran.c new file mode 100644 index 0000000..b5e8f1a --- /dev/null +++ b/libpng/pngrtran.c @@ -0,0 +1,4203 @@ + +/* pngrtran.c - transforms the data in a row for PNG readers + * + * Last changed in libpng 1.4.2 [May 6, 2010] + * Copyright (c) 1998-2010 Glenn Randers-Pehrson + * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) + * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) + * + * This code is released under the libpng license. + * For conditions of distribution and use, see the disclaimer + * and license in png.h + * + * This file contains functions optionally called by an application + * in order to tell libpng how to handle data when reading a PNG. + * Transformations that are used in both reading and writing are + * in pngtrans.c. + */ + +#define PNG_NO_PEDANTIC_WARNINGS +#include "png.h" +#ifdef PNG_READ_SUPPORTED +#include "pngpriv.h" + +/* Set the action on getting a CRC error for an ancillary or critical chunk. */ +void PNGAPI +png_set_crc_action(png_structp png_ptr, int crit_action, int ancil_action) +{ + png_debug(1, "in png_set_crc_action"); + + if (png_ptr == NULL) + return; + + /* Tell libpng how we react to CRC errors in critical chunks */ + switch (crit_action) + { + case PNG_CRC_NO_CHANGE: /* Leave setting as is */ + break; + + case PNG_CRC_WARN_USE: /* Warn/use data */ + png_ptr->flags &= ~PNG_FLAG_CRC_CRITICAL_MASK; + png_ptr->flags |= PNG_FLAG_CRC_CRITICAL_USE; + break; + + case PNG_CRC_QUIET_USE: /* Quiet/use data */ + png_ptr->flags &= ~PNG_FLAG_CRC_CRITICAL_MASK; + png_ptr->flags |= PNG_FLAG_CRC_CRITICAL_USE | + PNG_FLAG_CRC_CRITICAL_IGNORE; + break; + + case PNG_CRC_WARN_DISCARD: /* Not a valid action for critical data */ + png_warning(png_ptr, + "Can't discard critical data on CRC error"); + case PNG_CRC_ERROR_QUIT: /* Error/quit */ + + case PNG_CRC_DEFAULT: + default: + png_ptr->flags &= ~PNG_FLAG_CRC_CRITICAL_MASK; + break; + } + + /* Tell libpng how we react to CRC errors in ancillary chunks */ + switch (ancil_action) + { + case PNG_CRC_NO_CHANGE: /* Leave setting as is */ + break; + + case PNG_CRC_WARN_USE: /* Warn/use data */ + png_ptr->flags &= ~PNG_FLAG_CRC_ANCILLARY_MASK; + png_ptr->flags |= PNG_FLAG_CRC_ANCILLARY_USE; + break; + + case PNG_CRC_QUIET_USE: /* Quiet/use data */ + png_ptr->flags &= ~PNG_FLAG_CRC_ANCILLARY_MASK; + png_ptr->flags |= PNG_FLAG_CRC_ANCILLARY_USE | + PNG_FLAG_CRC_ANCILLARY_NOWARN; + break; + + case PNG_CRC_ERROR_QUIT: /* Error/quit */ + png_ptr->flags &= ~PNG_FLAG_CRC_ANCILLARY_MASK; + png_ptr->flags |= PNG_FLAG_CRC_ANCILLARY_NOWARN; + break; + + case PNG_CRC_WARN_DISCARD: /* Warn/discard data */ + + case PNG_CRC_DEFAULT: + default: + png_ptr->flags &= ~PNG_FLAG_CRC_ANCILLARY_MASK; + break; + } +} + +#if defined(PNG_READ_BACKGROUND_SUPPORTED) && \ + defined(PNG_FLOATING_POINT_SUPPORTED) +/* Handle alpha and tRNS via a background color */ +void PNGAPI +png_set_background(png_structp png_ptr, + png_color_16p background_color, int background_gamma_code, + int need_expand, double background_gamma) +{ + png_debug(1, "in png_set_background"); + + if (png_ptr == NULL) + return; + if (background_gamma_code == PNG_BACKGROUND_GAMMA_UNKNOWN) + { + png_warning(png_ptr, "Application must supply a known background gamma"); + return; + } + + png_ptr->transformations |= PNG_BACKGROUND; + png_memcpy(&(png_ptr->background), background_color, + png_sizeof(png_color_16)); + png_ptr->background_gamma = (float)background_gamma; + png_ptr->background_gamma_type = (png_byte)(background_gamma_code); + png_ptr->transformations |= (need_expand ? PNG_BACKGROUND_EXPAND : 0); +} +#endif + +#ifdef PNG_READ_16_TO_8_SUPPORTED +/* Strip 16 bit depth files to 8 bit depth */ +void PNGAPI +png_set_strip_16(png_structp png_ptr) +{ + png_debug(1, "in png_set_strip_16"); + + if (png_ptr == NULL) + return; + png_ptr->transformations |= PNG_16_TO_8; +} +#endif + +#ifdef PNG_READ_STRIP_ALPHA_SUPPORTED +void PNGAPI +png_set_strip_alpha(png_structp png_ptr) +{ + png_debug(1, "in png_set_strip_alpha"); + + if (png_ptr == NULL) + return; + png_ptr->flags |= PNG_FLAG_STRIP_ALPHA; +} +#endif + +#ifdef PNG_READ_QUANTIZE_SUPPORTED +/* Quantize file to 8 bit. Supply a palette, the current number + * of elements in the palette, the maximum number of elements + * allowed, and a histogram if possible. If the current number + * of colors is greater then the maximum number, the palette will be + * modified to fit in the maximum number. "full_quantize" indicates + * whether we need a quantizeing cube set up for RGB images, or if we + * simply are reducing the number of colors in a paletted image. + */ + +typedef struct png_dsort_struct +{ + struct png_dsort_struct FAR * next; + png_byte left; + png_byte right; +} png_dsort; +typedef png_dsort FAR * png_dsortp; +typedef png_dsort FAR * FAR * png_dsortpp; + +void PNGAPI +png_set_quantize(png_structp png_ptr, png_colorp palette, + int num_palette, int maximum_colors, png_uint_16p histogram, + int full_quantize) +{ + png_debug(1, "in png_set_quantize"); + + if (png_ptr == NULL) + return; + png_ptr->transformations |= PNG_QUANTIZE; + + if (!full_quantize) + { + int i; + + png_ptr->quantize_index = (png_bytep)png_malloc(png_ptr, + (png_uint_32)(num_palette * png_sizeof(png_byte))); + for (i = 0; i < num_palette; i++) + png_ptr->quantize_index[i] = (png_byte)i; + } + + if (num_palette > maximum_colors) + { + if (histogram != NULL) + { + /* This is easy enough, just throw out the least used colors. + * Perhaps not the best solution, but good enough. + */ + + int i; + + /* Initialize an array to sort colors */ + png_ptr->quantize_sort = (png_bytep)png_malloc(png_ptr, + (png_uint_32)(num_palette * png_sizeof(png_byte))); + + /* Initialize the quantize_sort array */ + for (i = 0; i < num_palette; i++) + png_ptr->quantize_sort[i] = (png_byte)i; + + /* Find the least used palette entries by starting a + * bubble sort, and running it until we have sorted + * out enough colors. Note that we don't care about + * sorting all the colors, just finding which are + * least used. + */ + + for (i = num_palette - 1; i >= maximum_colors; i--) + { + int done; /* To stop early if the list is pre-sorted */ + int j; + + done = 1; + for (j = 0; j < i; j++) + { + if (histogram[png_ptr->quantize_sort[j]] + < histogram[png_ptr->quantize_sort[j + 1]]) + { + png_byte t; + + t = png_ptr->quantize_sort[j]; + png_ptr->quantize_sort[j] = png_ptr->quantize_sort[j + 1]; + png_ptr->quantize_sort[j + 1] = t; + done = 0; + } + } + if (done) + break; + } + + /* Swap the palette around, and set up a table, if necessary */ + if (full_quantize) + { + int j = num_palette; + + /* Put all the useful colors within the max, but don't + * move the others. + */ + for (i = 0; i < maximum_colors; i++) + { + if ((int)png_ptr->quantize_sort[i] >= maximum_colors) + { + do + j--; + while ((int)png_ptr->quantize_sort[j] >= maximum_colors); + palette[i] = palette[j]; + } + } + } + else + { + int j = num_palette; + + /* Move all the used colors inside the max limit, and + * develop a translation table. + */ + for (i = 0; i < maximum_colors; i++) + { + /* Only move the colors we need to */ + if ((int)png_ptr->quantize_sort[i] >= maximum_colors) + { + png_color tmp_color; + + do + j--; + while ((int)png_ptr->quantize_sort[j] >= maximum_colors); + + tmp_color = palette[j]; + palette[j] = palette[i]; + palette[i] = tmp_color; + /* Indicate where the color went */ + png_ptr->quantize_index[j] = (png_byte)i; + png_ptr->quantize_index[i] = (png_byte)j; + } + } + + /* Find closest color for those colors we are not using */ + for (i = 0; i < num_palette; i++) + { + if ((int)png_ptr->quantize_index[i] >= maximum_colors) + { + int min_d, k, min_k, d_index; + + /* Find the closest color to one we threw out */ + d_index = png_ptr->quantize_index[i]; + min_d = PNG_COLOR_DIST(palette[d_index], palette[0]); + for (k = 1, min_k = 0; k < maximum_colors; k++) + { + int d; + + d = PNG_COLOR_DIST(palette[d_index], palette[k]); + + if (d < min_d) + { + min_d = d; + min_k = k; + } + } + /* Point to closest color */ + png_ptr->quantize_index[i] = (png_byte)min_k; + } + } + } + png_free(png_ptr, png_ptr->quantize_sort); + png_ptr->quantize_sort = NULL; + } + else + { + /* This is much harder to do simply (and quickly). Perhaps + * we need to go through a median cut routine, but those + * don't always behave themselves with only a few colors + * as input. So we will just find the closest two colors, + * and throw out one of them (chosen somewhat randomly). + * [We don't understand this at all, so if someone wants to + * work on improving it, be our guest - AED, GRP] + */ + int i; + int max_d; + int num_new_palette; + png_dsortp t; + png_dsortpp hash; + + t = NULL; + + /* Initialize palette index arrays */ + png_ptr->index_to_palette = (png_bytep)png_malloc(png_ptr, + (png_uint_32)(num_palette * png_sizeof(png_byte))); + png_ptr->palette_to_index = (png_bytep)png_malloc(png_ptr, + (png_uint_32)(num_palette * png_sizeof(png_byte))); + + /* Initialize the sort array */ + for (i = 0; i < num_palette; i++) + { + png_ptr->index_to_palette[i] = (png_byte)i; + png_ptr->palette_to_index[i] = (png_byte)i; + } + + hash = (png_dsortpp)png_calloc(png_ptr, (png_uint_32)(769 * + png_sizeof(png_dsortp))); + + num_new_palette = num_palette; + + /* Initial wild guess at how far apart the farthest pixel + * pair we will be eliminating will be. Larger + * numbers mean more areas will be allocated, Smaller + * numbers run the risk of not saving enough data, and + * having to do this all over again. + * + * I have not done extensive checking on this number. + */ + max_d = 96; + + while (num_new_palette > maximum_colors) + { + for (i = 0; i < num_new_palette - 1; i++) + { + int j; + + for (j = i + 1; j < num_new_palette; j++) + { + int d; + + d = PNG_COLOR_DIST(palette[i], palette[j]); + + if (d <= max_d) + { + + t = (png_dsortp)png_malloc_warn(png_ptr, + (png_uint_32)(png_sizeof(png_dsort))); + if (t == NULL) + break; + t->next = hash[d]; + t->left = (png_byte)i; + t->right = (png_byte)j; + hash[d] = t; + } + } + if (t == NULL) + break; + } + + if (t != NULL) + for (i = 0; i <= max_d; i++) + { + if (hash[i] != NULL) + { + png_dsortp p; + + for (p = hash[i]; p; p = p->next) + { + if ((int)png_ptr->index_to_palette[p->left] + < num_new_palette && + (int)png_ptr->index_to_palette[p->right] + < num_new_palette) + { + int j, next_j; + + if (num_new_palette & 0x01) + { + j = p->left; + next_j = p->right; + } + else + { + j = p->right; + next_j = p->left; + } + + num_new_palette--; + palette[png_ptr->index_to_palette[j]] + = palette[num_new_palette]; + if (!full_quantize) + { + int k; + + for (k = 0; k < num_palette; k++) + { + if (png_ptr->quantize_index[k] == + png_ptr->index_to_palette[j]) + png_ptr->quantize_index[k] = + png_ptr->index_to_palette[next_j]; + if ((int)png_ptr->quantize_index[k] == + num_new_palette) + png_ptr->quantize_index[k] = + png_ptr->index_to_palette[j]; + } + } + + png_ptr->index_to_palette[png_ptr->palette_to_index + [num_new_palette]] = png_ptr->index_to_palette[j]; + png_ptr->palette_to_index[png_ptr->index_to_palette[j]] + = png_ptr->palette_to_index[num_new_palette]; + + png_ptr->index_to_palette[j] = + (png_byte)num_new_palette; + png_ptr->palette_to_index[num_new_palette] = + (png_byte)j; + } + if (num_new_palette <= maximum_colors) + break; + } + if (num_new_palette <= maximum_colors) + break; + } + } + + for (i = 0; i < 769; i++) + { + if (hash[i] != NULL) + { + png_dsortp p = hash[i]; + while (p) + { + t = p->next; + png_free(png_ptr, p); + p = t; + } + } + hash[i] = 0; + } + max_d += 96; + } + png_free(png_ptr, hash); + png_free(png_ptr, png_ptr->palette_to_index); + png_free(png_ptr, png_ptr->index_to_palette); + png_ptr->palette_to_index = NULL; + png_ptr->index_to_palette = NULL; + } + num_palette = maximum_colors; + } + if (png_ptr->palette == NULL) + { + png_ptr->palette = palette; + } + png_ptr->num_palette = (png_uint_16)num_palette; + + if (full_quantize) + { + int i; + png_bytep distance; + int total_bits = PNG_QUANTIZE_RED_BITS + PNG_QUANTIZE_GREEN_BITS + + PNG_QUANTIZE_BLUE_BITS; + int num_red = (1 << PNG_QUANTIZE_RED_BITS); + int num_green = (1 << PNG_QUANTIZE_GREEN_BITS); + int num_blue = (1 << PNG_QUANTIZE_BLUE_BITS); + png_size_t num_entries = ((png_size_t)1 << total_bits); + + png_ptr->palette_lookup = (png_bytep )png_calloc(png_ptr, + (png_uint_32)(num_entries * png_sizeof(png_byte))); + + distance = (png_bytep)png_malloc(png_ptr, (png_uint_32)(num_entries * + png_sizeof(png_byte))); + png_memset(distance, 0xff, num_entries * png_sizeof(png_byte)); + + for (i = 0; i < num_palette; i++) + { + int ir, ig, ib; + int r = (palette[i].red >> (8 - PNG_QUANTIZE_RED_BITS)); + int g = (palette[i].green >> (8 - PNG_QUANTIZE_GREEN_BITS)); + int b = (palette[i].blue >> (8 - PNG_QUANTIZE_BLUE_BITS)); + + for (ir = 0; ir < num_red; ir++) + { + /* int dr = abs(ir - r); */ + int dr = ((ir > r) ? ir - r : r - ir); + int index_r = (ir << (PNG_QUANTIZE_BLUE_BITS + + PNG_QUANTIZE_GREEN_BITS)); + + for (ig = 0; ig < num_green; ig++) + { + /* int dg = abs(ig - g); */ + int dg = ((ig > g) ? ig - g : g - ig); + int dt = dr + dg; + int dm = ((dr > dg) ? dr : dg); + int index_g = index_r | (ig << PNG_QUANTIZE_BLUE_BITS); + + for (ib = 0; ib < num_blue; ib++) + { + int d_index = index_g | ib; + /* int db = abs(ib - b); */ + int db = ((ib > b) ? ib - b : b - ib); + int dmax = ((dm > db) ? dm : db); + int d = dmax + dt + db; + + if (d < (int)distance[d_index]) + { + distance[d_index] = (png_byte)d; + png_ptr->palette_lookup[d_index] = (png_byte)i; + } + } + } + } + } + + png_free(png_ptr, distance); + } +} +#endif /* PNG_READ_QUANTIZE_SUPPORTED */ + +#if defined(PNG_READ_GAMMA_SUPPORTED) && defined(PNG_FLOATING_POINT_SUPPORTED) +/* Transform the image from the file_gamma to the screen_gamma. We + * only do transformations on images where the file_gamma and screen_gamma + * are not close reciprocals, otherwise it slows things down slightly, and + * also needlessly introduces small errors. + * + * We will turn off gamma transformation later if no semitransparent entries + * are present in the tRNS array for palette images. We can't do it here + * because we don't necessarily have the tRNS chunk yet. + */ +void PNGAPI +png_set_gamma(png_structp png_ptr, double scrn_gamma, double file_gamma) +{ + png_debug(1, "in png_set_gamma"); + + if (png_ptr == NULL) + return; + + if ((fabs(scrn_gamma * file_gamma - 1.0) > PNG_GAMMA_THRESHOLD) || + (png_ptr->color_type & PNG_COLOR_MASK_ALPHA) || + (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)) + png_ptr->transformations |= PNG_GAMMA; + png_ptr->gamma = (float)file_gamma; + png_ptr->screen_gamma = (float)scrn_gamma; +} +#endif + +#ifdef PNG_READ_EXPAND_SUPPORTED +/* Expand paletted images to RGB, expand grayscale images of + * less than 8-bit depth to 8-bit depth, and expand tRNS chunks + * to alpha channels. + */ +void PNGAPI +png_set_expand(png_structp png_ptr) +{ + png_debug(1, "in png_set_expand"); + + if (png_ptr == NULL) + return; + + png_ptr->transformations |= (PNG_EXPAND | PNG_EXPAND_tRNS); + png_ptr->flags &= ~PNG_FLAG_ROW_INIT; +} + +/* GRR 19990627: the following three functions currently are identical + * to png_set_expand(). However, it is entirely reasonable that someone + * might wish to expand an indexed image to RGB but *not* expand a single, + * fully transparent palette entry to a full alpha channel--perhaps instead + * convert tRNS to the grayscale/RGB format (16-bit RGB value), or replace + * the transparent color with a particular RGB value, or drop tRNS entirely. + * IOW, a future version of the library may make the transformations flag + * a bit more fine-grained, with separate bits for each of these three + * functions. + * + * More to the point, these functions make it obvious what libpng will be + * doing, whereas "expand" can (and does) mean any number of things. + * + * GRP 20060307: In libpng-1.2.9, png_set_gray_1_2_4_to_8() was modified + * to expand only the sample depth but not to expand the tRNS to alpha + * and its name was changed to png_set_expand_gray_1_2_4_to_8(). + */ + +/* Expand paletted images to RGB. */ +void PNGAPI +png_set_palette_to_rgb(png_structp png_ptr) +{ + png_debug(1, "in png_set_palette_to_rgb"); + + if (png_ptr == NULL) + return; + + png_ptr->transformations |= (PNG_EXPAND | PNG_EXPAND_tRNS); + png_ptr->flags &= ~PNG_FLAG_ROW_INIT; +} + +/* Expand grayscale images of less than 8-bit depth to 8 bits. */ +void PNGAPI +png_set_expand_gray_1_2_4_to_8(png_structp png_ptr) +{ + png_debug(1, "in png_set_expand_gray_1_2_4_to_8"); + + if (png_ptr == NULL) + return; + + png_ptr->transformations |= PNG_EXPAND; + png_ptr->flags &= ~PNG_FLAG_ROW_INIT; +} + + + +/* Expand tRNS chunks to alpha channels. */ +void PNGAPI +png_set_tRNS_to_alpha(png_structp png_ptr) +{ + png_debug(1, "in png_set_tRNS_to_alpha"); + + png_ptr->transformations |= (PNG_EXPAND | PNG_EXPAND_tRNS); + png_ptr->flags &= ~PNG_FLAG_ROW_INIT; +} +#endif /* defined(PNG_READ_EXPAND_SUPPORTED) */ + +#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED +void PNGAPI +png_set_gray_to_rgb(png_structp png_ptr) +{ + png_debug(1, "in png_set_gray_to_rgb"); + + png_ptr->transformations |= PNG_GRAY_TO_RGB; + png_ptr->flags &= ~PNG_FLAG_ROW_INIT; +} +#endif + +#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED +#ifdef PNG_FLOATING_POINT_SUPPORTED +/* Convert a RGB image to a grayscale of the same width. This allows us, + * for example, to convert a 24 bpp RGB image into an 8 bpp grayscale image. + */ + +void PNGAPI +png_set_rgb_to_gray(png_structp png_ptr, int error_action, double red, + double green) +{ + int red_fixed = (int)((float)red*100000.0 + 0.5); + int green_fixed = (int)((float)green*100000.0 + 0.5); + if (png_ptr == NULL) + return; + png_set_rgb_to_gray_fixed(png_ptr, error_action, red_fixed, green_fixed); +} +#endif + +void PNGAPI +png_set_rgb_to_gray_fixed(png_structp png_ptr, int error_action, + png_fixed_point red, png_fixed_point green) +{ + png_debug(1, "in png_set_rgb_to_gray"); + + if (png_ptr == NULL) + return; + + switch(error_action) + { + case 1: png_ptr->transformations |= PNG_RGB_TO_GRAY; + break; + + case 2: png_ptr->transformations |= PNG_RGB_TO_GRAY_WARN; + break; + + case 3: png_ptr->transformations |= PNG_RGB_TO_GRAY_ERR; + } + if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) +#ifdef PNG_READ_EXPAND_SUPPORTED + png_ptr->transformations |= PNG_EXPAND; +#else + { + png_warning(png_ptr, + "Cannot do RGB_TO_GRAY without EXPAND_SUPPORTED"); + png_ptr->transformations &= ~PNG_RGB_TO_GRAY; + } +#endif + { + png_uint_16 red_int, green_int; + if (red < 0 || green < 0) + { + red_int = 6968; /* .212671 * 32768 + .5 */ + green_int = 23434; /* .715160 * 32768 + .5 */ + } + else if (red + green < 100000L) + { + red_int = (png_uint_16)(((png_uint_32)red*32768L)/100000L); + green_int = (png_uint_16)(((png_uint_32)green*32768L)/100000L); + } + else + { + png_warning(png_ptr, "ignoring out of range rgb_to_gray coefficients"); + red_int = 6968; + green_int = 23434; + } + png_ptr->rgb_to_gray_red_coeff = red_int; + png_ptr->rgb_to_gray_green_coeff = green_int; + png_ptr->rgb_to_gray_blue_coeff = + (png_uint_16)(32768 - red_int - green_int); + } +} +#endif + +#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \ + defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) +void PNGAPI +png_set_read_user_transform_fn(png_structp png_ptr, png_user_transform_ptr + read_user_transform_fn) +{ + png_debug(1, "in png_set_read_user_transform_fn"); + + if (png_ptr == NULL) + return; + +#ifdef PNG_READ_USER_TRANSFORM_SUPPORTED + png_ptr->transformations |= PNG_USER_TRANSFORM; + png_ptr->read_user_transform_fn = read_user_transform_fn; +#endif +} +#endif + +/* Initialize everything needed for the read. This includes modifying + * the palette. + */ +void /* PRIVATE */ +png_init_read_transformations(png_structp png_ptr) +{ + png_debug(1, "in png_init_read_transformations"); + + { +#if defined(PNG_READ_BACKGROUND_SUPPORTED) || \ + defined(PNG_READ_SHIFT_SUPPORTED) || \ + defined(PNG_READ_GAMMA_SUPPORTED) + int color_type = png_ptr->color_type; +#endif + +#if defined(PNG_READ_EXPAND_SUPPORTED) && defined(PNG_READ_BACKGROUND_SUPPORTED) + +#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED + /* Detect gray background and attempt to enable optimization + * for gray --> RGB case + * + * Note: if PNG_BACKGROUND_EXPAND is set and color_type is either RGB or + * RGB_ALPHA (in which case need_expand is superfluous anyway), the + * background color might actually be gray yet not be flagged as such. + * This is not a problem for the current code, which uses + * PNG_BACKGROUND_IS_GRAY only to decide when to do the + * png_do_gray_to_rgb() transformation. + */ + if ((png_ptr->transformations & PNG_BACKGROUND_EXPAND) && + !(color_type & PNG_COLOR_MASK_COLOR)) + { + png_ptr->mode |= PNG_BACKGROUND_IS_GRAY; + } else if ((png_ptr->transformations & PNG_BACKGROUND) && + !(png_ptr->transformations & PNG_BACKGROUND_EXPAND) && + (png_ptr->transformations & PNG_GRAY_TO_RGB) && + png_ptr->background.red == png_ptr->background.green && + png_ptr->background.red == png_ptr->background.blue) + { + png_ptr->mode |= PNG_BACKGROUND_IS_GRAY; + png_ptr->background.gray = png_ptr->background.red; + } +#endif + + if ((png_ptr->transformations & PNG_BACKGROUND_EXPAND) && + (png_ptr->transformations & PNG_EXPAND)) + { + if (!(color_type & PNG_COLOR_MASK_COLOR)) /* i.e., GRAY or GRAY_ALPHA */ + { + /* Expand background and tRNS chunks */ + switch (png_ptr->bit_depth) + { + case 1: + png_ptr->background.gray *= (png_uint_16)0xff; + png_ptr->background.red = png_ptr->background.green + = png_ptr->background.blue = png_ptr->background.gray; + if (!(png_ptr->transformations & PNG_EXPAND_tRNS)) + { + png_ptr->trans_color.gray *= (png_uint_16)0xff; + png_ptr->trans_color.red = png_ptr->trans_color.green + = png_ptr->trans_color.blue = png_ptr->trans_color.gray; + } + break; + + case 2: + png_ptr->background.gray *= (png_uint_16)0x55; + png_ptr->background.red = png_ptr->background.green + = png_ptr->background.blue = png_ptr->background.gray; + if (!(png_ptr->transformations & PNG_EXPAND_tRNS)) + { + png_ptr->trans_color.gray *= (png_uint_16)0x55; + png_ptr->trans_color.red = png_ptr->trans_color.green + = png_ptr->trans_color.blue = png_ptr->trans_color.gray; + } + break; + + case 4: + png_ptr->background.gray *= (png_uint_16)0x11; + png_ptr->background.red = png_ptr->background.green + = png_ptr->background.blue = png_ptr->background.gray; + if (!(png_ptr->transformations & PNG_EXPAND_tRNS)) + { + png_ptr->trans_color.gray *= (png_uint_16)0x11; + png_ptr->trans_color.red = png_ptr->trans_color.green + = png_ptr->trans_color.blue = png_ptr->trans_color.gray; + } + break; + + case 8: + + case 16: + png_ptr->background.red = png_ptr->background.green + = png_ptr->background.blue = png_ptr->background.gray; + break; + } + } + else if (color_type == PNG_COLOR_TYPE_PALETTE) + { + png_ptr->background.red = + png_ptr->palette[png_ptr->background.index].red; + png_ptr->background.green = + png_ptr->palette[png_ptr->background.index].green; + png_ptr->background.blue = + png_ptr->palette[png_ptr->background.index].blue; + +#ifdef PNG_READ_INVERT_ALPHA_SUPPORTED + if (png_ptr->transformations & PNG_INVERT_ALPHA) + { +#ifdef PNG_READ_EXPAND_SUPPORTED + if (!(png_ptr->transformations & PNG_EXPAND_tRNS)) +#endif + { + /* Invert the alpha channel (in tRNS) unless the pixels are + * going to be expanded, in which case leave it for later + */ + int i, istop; + istop=(int)png_ptr->num_trans; + for (i=0; itrans_alpha[i] = (png_byte)(255 - png_ptr->trans_alpha[i]); + } + } +#endif + + } + } +#endif + +#if defined(PNG_READ_BACKGROUND_SUPPORTED) && defined(PNG_READ_GAMMA_SUPPORTED) + png_ptr->background_1 = png_ptr->background; +#endif +#if defined(PNG_READ_GAMMA_SUPPORTED) && defined(PNG_FLOATING_POINT_SUPPORTED) + + if ((color_type == PNG_COLOR_TYPE_PALETTE && png_ptr->num_trans != 0) + && (fabs(png_ptr->screen_gamma * png_ptr->gamma - 1.0) + < PNG_GAMMA_THRESHOLD)) + { + int i, k; + k=0; + for (i=0; inum_trans; i++) + { + if (png_ptr->trans_alpha[i] != 0 && png_ptr->trans_alpha[i] != 0xff) + k=1; /* Partial transparency is present */ + } + if (k == 0) + png_ptr->transformations &= ~PNG_GAMMA; + } + + if ((png_ptr->transformations & (PNG_GAMMA | PNG_RGB_TO_GRAY)) && + png_ptr->gamma != 0.0) + { + png_build_gamma_table(png_ptr, png_ptr->bit_depth); + +#ifdef PNG_READ_BACKGROUND_SUPPORTED + if (png_ptr->transformations & PNG_BACKGROUND) + { + if (color_type == PNG_COLOR_TYPE_PALETTE) + { + /* Could skip if no transparency */ + png_color back, back_1; + png_colorp palette = png_ptr->palette; + int num_palette = png_ptr->num_palette; + int i; + if (png_ptr->background_gamma_type == PNG_BACKGROUND_GAMMA_FILE) + { + back.red = png_ptr->gamma_table[png_ptr->background.red]; + back.green = png_ptr->gamma_table[png_ptr->background.green]; + back.blue = png_ptr->gamma_table[png_ptr->background.blue]; + + back_1.red = png_ptr->gamma_to_1[png_ptr->background.red]; + back_1.green = png_ptr->gamma_to_1[png_ptr->background.green]; + back_1.blue = png_ptr->gamma_to_1[png_ptr->background.blue]; + } + else + { + double g, gs; + + switch (png_ptr->background_gamma_type) + { + case PNG_BACKGROUND_GAMMA_SCREEN: + g = (png_ptr->screen_gamma); + gs = 1.0; + break; + + case PNG_BACKGROUND_GAMMA_FILE: + g = 1.0 / (png_ptr->gamma); + gs = 1.0 / (png_ptr->gamma * png_ptr->screen_gamma); + break; + + case PNG_BACKGROUND_GAMMA_UNIQUE: + g = 1.0 / (png_ptr->background_gamma); + gs = 1.0 / (png_ptr->background_gamma * + png_ptr->screen_gamma); + break; + default: + g = 1.0; /* back_1 */ + gs = 1.0; /* back */ + } + + if ( fabs(gs - 1.0) < PNG_GAMMA_THRESHOLD) + { + back.red = (png_byte)png_ptr->background.red; + back.green = (png_byte)png_ptr->background.green; + back.blue = (png_byte)png_ptr->background.blue; + } + else + { + back.red = (png_byte)(pow( + (double)png_ptr->background.red/255.0, gs) * 255.0 + .5); + back.green = (png_byte)(pow( + (double)png_ptr->background.green/255.0, gs) * 255.0 + + .5); + back.blue = (png_byte)(pow( + (double)png_ptr->background.blue/255.0, gs) * 255.0 + .5); + } + + back_1.red = (png_byte)(pow( + (double)png_ptr->background.red/255.0, g) * 255.0 + .5); + back_1.green = (png_byte)(pow( + (double)png_ptr->background.green/255.0, g) * 255.0 + .5); + back_1.blue = (png_byte)(pow( + (double)png_ptr->background.blue/255.0, g) * 255.0 + .5); + } + for (i = 0; i < num_palette; i++) + { + if (i < (int)png_ptr->num_trans && png_ptr->trans_alpha[i] != 0xff) + { + if (png_ptr->trans_alpha[i] == 0) + { + palette[i] = back; + } + else /* if (png_ptr->trans_alpha[i] != 0xff) */ + { + png_byte v, w; + + v = png_ptr->gamma_to_1[palette[i].red]; + png_composite(w, v, png_ptr->trans_alpha[i], back_1.red); + palette[i].red = png_ptr->gamma_from_1[w]; + + v = png_ptr->gamma_to_1[palette[i].green]; + png_composite(w, v, png_ptr->trans_alpha[i], back_1.green); + palette[i].green = png_ptr->gamma_from_1[w]; + + v = png_ptr->gamma_to_1[palette[i].blue]; + png_composite(w, v, png_ptr->trans_alpha[i], back_1.blue); + palette[i].blue = png_ptr->gamma_from_1[w]; + } + } + else + { + palette[i].red = png_ptr->gamma_table[palette[i].red]; + palette[i].green = png_ptr->gamma_table[palette[i].green]; + palette[i].blue = png_ptr->gamma_table[palette[i].blue]; + } + } + /* Prevent the transformations being done again, and make sure + * that the now spurious alpha channel is stripped - the code + * has just reduced background composition and gamma correction + * to a simple alpha channel strip. + */ + png_ptr->transformations &= ~PNG_BACKGROUND; + png_ptr->transformations &= ~PNG_GAMMA; + png_ptr->transformations |= PNG_STRIP_ALPHA; + } + /* if (png_ptr->background_gamma_type!=PNG_BACKGROUND_GAMMA_UNKNOWN) */ + else + /* color_type != PNG_COLOR_TYPE_PALETTE */ + { + double m = (double)(((png_uint_32)1 << png_ptr->bit_depth) - 1); + double g = 1.0; + double gs = 1.0; + + switch (png_ptr->background_gamma_type) + { + case PNG_BACKGROUND_GAMMA_SCREEN: + g = (png_ptr->screen_gamma); + gs = 1.0; + break; + + case PNG_BACKGROUND_GAMMA_FILE: + g = 1.0 / (png_ptr->gamma); + gs = 1.0 / (png_ptr->gamma * png_ptr->screen_gamma); + break; + + case PNG_BACKGROUND_GAMMA_UNIQUE: + g = 1.0 / (png_ptr->background_gamma); + gs = 1.0 / (png_ptr->background_gamma * + png_ptr->screen_gamma); + break; + } + + png_ptr->background_1.gray = (png_uint_16)(pow( + (double)png_ptr->background.gray / m, g) * m + .5); + png_ptr->background.gray = (png_uint_16)(pow( + (double)png_ptr->background.gray / m, gs) * m + .5); + + if ((png_ptr->background.red != png_ptr->background.green) || + (png_ptr->background.red != png_ptr->background.blue) || + (png_ptr->background.red != png_ptr->background.gray)) + { + /* RGB or RGBA with color background */ + png_ptr->background_1.red = (png_uint_16)(pow( + (double)png_ptr->background.red / m, g) * m + .5); + png_ptr->background_1.green = (png_uint_16)(pow( + (double)png_ptr->background.green / m, g) * m + .5); + png_ptr->background_1.blue = (png_uint_16)(pow( + (double)png_ptr->background.blue / m, g) * m + .5); + png_ptr->background.red = (png_uint_16)(pow( + (double)png_ptr->background.red / m, gs) * m + .5); + png_ptr->background.green = (png_uint_16)(pow( + (double)png_ptr->background.green / m, gs) * m + .5); + png_ptr->background.blue = (png_uint_16)(pow( + (double)png_ptr->background.blue / m, gs) * m + .5); + } + else + { + /* GRAY, GRAY ALPHA, RGB, or RGBA with gray background */ + png_ptr->background_1.red = png_ptr->background_1.green + = png_ptr->background_1.blue = png_ptr->background_1.gray; + png_ptr->background.red = png_ptr->background.green + = png_ptr->background.blue = png_ptr->background.gray; + } + } + } + else + /* Transformation does not include PNG_BACKGROUND */ +#endif /* PNG_READ_BACKGROUND_SUPPORTED */ + if (color_type == PNG_COLOR_TYPE_PALETTE) + { + png_colorp palette = png_ptr->palette; + int num_palette = png_ptr->num_palette; + int i; + + for (i = 0; i < num_palette; i++) + { + palette[i].red = png_ptr->gamma_table[palette[i].red]; + palette[i].green = png_ptr->gamma_table[palette[i].green]; + palette[i].blue = png_ptr->gamma_table[palette[i].blue]; + } + + /* Done the gamma correction. */ + png_ptr->transformations &= ~PNG_GAMMA; + } + } +#ifdef PNG_READ_BACKGROUND_SUPPORTED + else +#endif +#endif /* PNG_READ_GAMMA_SUPPORTED && PNG_FLOATING_POINT_SUPPORTED */ +#ifdef PNG_READ_BACKGROUND_SUPPORTED + /* No GAMMA transformation */ + if ((png_ptr->transformations & PNG_BACKGROUND) && + (color_type == PNG_COLOR_TYPE_PALETTE)) + { + int i; + int istop = (int)png_ptr->num_trans; + png_color back; + png_colorp palette = png_ptr->palette; + + back.red = (png_byte)png_ptr->background.red; + back.green = (png_byte)png_ptr->background.green; + back.blue = (png_byte)png_ptr->background.blue; + + for (i = 0; i < istop; i++) + { + if (png_ptr->trans_alpha[i] == 0) + { + palette[i] = back; + } + else if (png_ptr->trans_alpha[i] != 0xff) + { + /* The png_composite() macro is defined in png.h */ + png_composite(palette[i].red, palette[i].red, + png_ptr->trans_alpha[i], back.red); + png_composite(palette[i].green, palette[i].green, + png_ptr->trans_alpha[i], back.green); + png_composite(palette[i].blue, palette[i].blue, + png_ptr->trans_alpha[i], back.blue); + } + } + + /* Handled alpha, still need to strip the channel. */ + png_ptr->transformations &= ~PNG_BACKGROUND; + png_ptr->transformations |= PNG_STRIP_ALPHA; + } +#endif /* PNG_READ_BACKGROUND_SUPPORTED */ + +#ifdef PNG_READ_SHIFT_SUPPORTED + if ((png_ptr->transformations & PNG_SHIFT) && + (color_type == PNG_COLOR_TYPE_PALETTE)) + { + png_uint_16 i; + png_uint_16 istop = png_ptr->num_palette; + int sr = 8 - png_ptr->sig_bit.red; + int sg = 8 - png_ptr->sig_bit.green; + int sb = 8 - png_ptr->sig_bit.blue; + + if (sr < 0 || sr > 8) + sr = 0; + if (sg < 0 || sg > 8) + sg = 0; + if (sb < 0 || sb > 8) + sb = 0; + for (i = 0; i < istop; i++) + { + png_ptr->palette[i].red >>= sr; + png_ptr->palette[i].green >>= sg; + png_ptr->palette[i].blue >>= sb; + } + } +#endif /* PNG_READ_SHIFT_SUPPORTED */ + } +#if !defined(PNG_READ_GAMMA_SUPPORTED) && !defined(PNG_READ_SHIFT_SUPPORTED) \ + && !defined(PNG_READ_BACKGROUND_SUPPORTED) + if (png_ptr) + return; +#endif +} + +/* Modify the info structure to reflect the transformations. The + * info should be updated so a PNG file could be written with it, + * assuming the transformations result in valid PNG data. + */ +void /* PRIVATE */ +png_read_transform_info(png_structp png_ptr, png_infop info_ptr) +{ + png_debug(1, "in png_read_transform_info"); + +#ifdef PNG_READ_EXPAND_SUPPORTED + if (png_ptr->transformations & PNG_EXPAND) + { + if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE) + { + if (png_ptr->num_trans && + (png_ptr->transformations & PNG_EXPAND_tRNS)) + info_ptr->color_type = PNG_COLOR_TYPE_RGB_ALPHA; + else + info_ptr->color_type = PNG_COLOR_TYPE_RGB; + info_ptr->bit_depth = 8; + info_ptr->num_trans = 0; + } + else + { + if (png_ptr->num_trans) + { + if (png_ptr->transformations & PNG_EXPAND_tRNS) + info_ptr->color_type |= PNG_COLOR_MASK_ALPHA; + } + if (info_ptr->bit_depth < 8) + info_ptr->bit_depth = 8; + info_ptr->num_trans = 0; + } + } +#endif + +#ifdef PNG_READ_BACKGROUND_SUPPORTED + if (png_ptr->transformations & PNG_BACKGROUND) + { + info_ptr->color_type &= ~PNG_COLOR_MASK_ALPHA; + info_ptr->num_trans = 0; + info_ptr->background = png_ptr->background; + } +#endif + +#ifdef PNG_READ_GAMMA_SUPPORTED + if (png_ptr->transformations & PNG_GAMMA) + { +#ifdef PNG_FLOATING_POINT_SUPPORTED + info_ptr->gamma = png_ptr->gamma; +#endif +#ifdef PNG_FIXED_POINT_SUPPORTED + info_ptr->int_gamma = png_ptr->int_gamma; +#endif + } +#endif + +#ifdef PNG_READ_16_TO_8_SUPPORTED + if ((png_ptr->transformations & PNG_16_TO_8) && (info_ptr->bit_depth == 16)) + info_ptr->bit_depth = 8; +#endif + +#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED + if (png_ptr->transformations & PNG_GRAY_TO_RGB) + info_ptr->color_type |= PNG_COLOR_MASK_COLOR; +#endif + +#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED + if (png_ptr->transformations & PNG_RGB_TO_GRAY) + info_ptr->color_type &= ~PNG_COLOR_MASK_COLOR; +#endif + +#ifdef PNG_READ_QUANTIZE_SUPPORTED + if (png_ptr->transformations & PNG_QUANTIZE) + { + if (((info_ptr->color_type == PNG_COLOR_TYPE_RGB) || + (info_ptr->color_type == PNG_COLOR_TYPE_RGB_ALPHA)) && + png_ptr->palette_lookup && info_ptr->bit_depth == 8) + { + info_ptr->color_type = PNG_COLOR_TYPE_PALETTE; + } + } +#endif + +#ifdef PNG_READ_PACK_SUPPORTED + if ((png_ptr->transformations & PNG_PACK) && (info_ptr->bit_depth < 8)) + info_ptr->bit_depth = 8; +#endif + + if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE) + info_ptr->channels = 1; + else if (info_ptr->color_type & PNG_COLOR_MASK_COLOR) + info_ptr->channels = 3; + else + info_ptr->channels = 1; + +#ifdef PNG_READ_STRIP_ALPHA_SUPPORTED + if (png_ptr->flags & PNG_FLAG_STRIP_ALPHA) + info_ptr->color_type &= ~PNG_COLOR_MASK_ALPHA; +#endif + + if (info_ptr->color_type & PNG_COLOR_MASK_ALPHA) + info_ptr->channels++; + +#ifdef PNG_READ_FILLER_SUPPORTED + /* STRIP_ALPHA and FILLER allowed: MASK_ALPHA bit stripped above */ + if ((png_ptr->transformations & PNG_FILLER) && + ((info_ptr->color_type == PNG_COLOR_TYPE_RGB) || + (info_ptr->color_type == PNG_COLOR_TYPE_GRAY))) + { + info_ptr->channels++; + /* If adding a true alpha channel not just filler */ + if (png_ptr->transformations & PNG_ADD_ALPHA) + info_ptr->color_type |= PNG_COLOR_MASK_ALPHA; + } +#endif + +#if defined(PNG_USER_TRANSFORM_PTR_SUPPORTED) && \ +defined(PNG_READ_USER_TRANSFORM_SUPPORTED) + if (png_ptr->transformations & PNG_USER_TRANSFORM) + { + if (info_ptr->bit_depth < png_ptr->user_transform_depth) + info_ptr->bit_depth = png_ptr->user_transform_depth; + if (info_ptr->channels < png_ptr->user_transform_channels) + info_ptr->channels = png_ptr->user_transform_channels; + } +#endif + + info_ptr->pixel_depth = (png_byte)(info_ptr->channels * + info_ptr->bit_depth); + + info_ptr->rowbytes = PNG_ROWBYTES(info_ptr->pixel_depth, info_ptr->width); + +#ifndef PNG_READ_EXPAND_SUPPORTED + if (png_ptr) + return; +#endif +} + +/* Transform the row. The order of transformations is significant, + * and is very touchy. If you add a transformation, take care to + * decide how it fits in with the other transformations here. + */ +void /* PRIVATE */ +png_do_read_transformations(png_structp png_ptr) +{ + png_debug(1, "in png_do_read_transformations"); + + if (png_ptr->row_buf == NULL) + { +#ifdef PNG_STDIO_SUPPORTED + char msg[50]; + + png_snprintf2(msg, 50, + "NULL row buffer for row %ld, pass %d", (long)png_ptr->row_number, + png_ptr->pass); + png_error(png_ptr, msg); +#else + png_error(png_ptr, "NULL row buffer"); +#endif + } +#ifdef PNG_WARN_UNINITIALIZED_ROW + if (!(png_ptr->flags & PNG_FLAG_ROW_INIT)) + /* Application has failed to call either png_read_start_image() + * or png_read_update_info() after setting transforms that expand + * pixels. This check added to libpng-1.2.19 + */ +#if (PNG_WARN_UNINITIALIZED_ROW==1) + png_error(png_ptr, "Uninitialized row"); +#else + png_warning(png_ptr, "Uninitialized row"); +#endif +#endif + +#ifdef PNG_READ_EXPAND_SUPPORTED + if (png_ptr->transformations & PNG_EXPAND) + { + if (png_ptr->row_info.color_type == PNG_COLOR_TYPE_PALETTE) + { + png_do_expand_palette(&(png_ptr->row_info), png_ptr->row_buf + 1, + png_ptr->palette, png_ptr->trans_alpha, png_ptr->num_trans); + } + else + { + if (png_ptr->num_trans && + (png_ptr->transformations & PNG_EXPAND_tRNS)) + png_do_expand(&(png_ptr->row_info), png_ptr->row_buf + 1, + &(png_ptr->trans_color)); + else + png_do_expand(&(png_ptr->row_info), png_ptr->row_buf + 1, + NULL); + } + } +#endif + +#ifdef PNG_READ_STRIP_ALPHA_SUPPORTED + if (png_ptr->flags & PNG_FLAG_STRIP_ALPHA) + png_do_strip_filler(&(png_ptr->row_info), png_ptr->row_buf + 1, + PNG_FLAG_FILLER_AFTER | (png_ptr->flags & PNG_FLAG_STRIP_ALPHA)); +#endif + +#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED + if (png_ptr->transformations & PNG_RGB_TO_GRAY) + { + int rgb_error = + png_do_rgb_to_gray(png_ptr, &(png_ptr->row_info), + png_ptr->row_buf + 1); + if (rgb_error) + { + png_ptr->rgb_to_gray_status=1; + if ((png_ptr->transformations & PNG_RGB_TO_GRAY) == + PNG_RGB_TO_GRAY_WARN) + png_warning(png_ptr, "png_do_rgb_to_gray found nongray pixel"); + if ((png_ptr->transformations & PNG_RGB_TO_GRAY) == + PNG_RGB_TO_GRAY_ERR) + png_error(png_ptr, "png_do_rgb_to_gray found nongray pixel"); + } + } +#endif + +/* From Andreas Dilger e-mail to png-implement, 26 March 1998: + * + * In most cases, the "simple transparency" should be done prior to doing + * gray-to-RGB, or you will have to test 3x as many bytes to check if a + * pixel is transparent. You would also need to make sure that the + * transparency information is upgraded to RGB. + * + * To summarize, the current flow is: + * - Gray + simple transparency -> compare 1 or 2 gray bytes and composite + * with background "in place" if transparent, + * convert to RGB if necessary + * - Gray + alpha -> composite with gray background and remove alpha bytes, + * convert to RGB if necessary + * + * To support RGB backgrounds for gray images we need: + * - Gray + simple transparency -> convert to RGB + simple transparency, + * compare 3 or 6 bytes and composite with + * background "in place" if transparent + * (3x compare/pixel compared to doing + * composite with gray bkgrnd) + * - Gray + alpha -> convert to RGB + alpha, composite with background and + * remove alpha bytes (3x float + * operations/pixel compared with composite + * on gray background) + * + * Greg's change will do this. The reason it wasn't done before is for + * performance, as this increases the per-pixel operations. If we would check + * in advance if the background was gray or RGB, and position the gray-to-RGB + * transform appropriately, then it would save a lot of work/time. + */ + +#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED + /* If gray -> RGB, do so now only if background is non-gray; else do later + * for performance reasons + */ + if ((png_ptr->transformations & PNG_GRAY_TO_RGB) && + !(png_ptr->mode & PNG_BACKGROUND_IS_GRAY)) + png_do_gray_to_rgb(&(png_ptr->row_info), png_ptr->row_buf + 1); +#endif + +#ifdef PNG_READ_BACKGROUND_SUPPORTED + if ((png_ptr->transformations & PNG_BACKGROUND) && + ((png_ptr->num_trans != 0 ) || + (png_ptr->color_type & PNG_COLOR_MASK_ALPHA))) + png_do_background(&(png_ptr->row_info), png_ptr->row_buf + 1, + &(png_ptr->trans_color), &(png_ptr->background) +#ifdef PNG_READ_GAMMA_SUPPORTED + , &(png_ptr->background_1), + png_ptr->gamma_table, png_ptr->gamma_from_1, + png_ptr->gamma_to_1, png_ptr->gamma_16_table, + png_ptr->gamma_16_from_1, png_ptr->gamma_16_to_1, + png_ptr->gamma_shift +#endif +); +#endif + +#ifdef PNG_READ_GAMMA_SUPPORTED + if ((png_ptr->transformations & PNG_GAMMA) && +#ifdef PNG_READ_BACKGROUND_SUPPORTED + !((png_ptr->transformations & PNG_BACKGROUND) && + ((png_ptr->num_trans != 0) || + (png_ptr->color_type & PNG_COLOR_MASK_ALPHA))) && +#endif + (png_ptr->color_type != PNG_COLOR_TYPE_PALETTE)) + png_do_gamma(&(png_ptr->row_info), png_ptr->row_buf + 1, + png_ptr->gamma_table, png_ptr->gamma_16_table, + png_ptr->gamma_shift); +#endif + +#ifdef PNG_READ_16_TO_8_SUPPORTED + if (png_ptr->transformations & PNG_16_TO_8) + png_do_chop(&(png_ptr->row_info), png_ptr->row_buf + 1); +#endif + +#ifdef PNG_READ_QUANTIZE_SUPPORTED + if (png_ptr->transformations & PNG_QUANTIZE) + { + png_do_quantize((png_row_infop)&(png_ptr->row_info), png_ptr->row_buf + 1, + png_ptr->palette_lookup, png_ptr->quantize_index); + if (png_ptr->row_info.rowbytes == (png_uint_32)0) + png_error(png_ptr, "png_do_quantize returned rowbytes=0"); + } +#endif + +#ifdef PNG_READ_INVERT_SUPPORTED + if (png_ptr->transformations & PNG_INVERT_MONO) + png_do_invert(&(png_ptr->row_info), png_ptr->row_buf + 1); +#endif + +#ifdef PNG_READ_SHIFT_SUPPORTED + if (png_ptr->transformations & PNG_SHIFT) + png_do_unshift(&(png_ptr->row_info), png_ptr->row_buf + 1, + &(png_ptr->shift)); +#endif + +#ifdef PNG_READ_PACK_SUPPORTED + if (png_ptr->transformations & PNG_PACK) + png_do_unpack(&(png_ptr->row_info), png_ptr->row_buf + 1); +#endif + +#ifdef PNG_READ_BGR_SUPPORTED + if (png_ptr->transformations & PNG_BGR) + png_do_bgr(&(png_ptr->row_info), png_ptr->row_buf + 1); +#endif + +#ifdef PNG_READ_PACKSWAP_SUPPORTED + if (png_ptr->transformations & PNG_PACKSWAP) + png_do_packswap(&(png_ptr->row_info), png_ptr->row_buf + 1); +#endif + +#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED + /* If gray -> RGB, do so now only if we did not do so above */ + if ((png_ptr->transformations & PNG_GRAY_TO_RGB) && + (png_ptr->mode & PNG_BACKGROUND_IS_GRAY)) + png_do_gray_to_rgb(&(png_ptr->row_info), png_ptr->row_buf + 1); +#endif + +#ifdef PNG_READ_FILLER_SUPPORTED + if (png_ptr->transformations & PNG_FILLER) + png_do_read_filler(&(png_ptr->row_info), png_ptr->row_buf + 1, + (png_uint_32)png_ptr->filler, png_ptr->flags); +#endif + +#ifdef PNG_READ_INVERT_ALPHA_SUPPORTED + if (png_ptr->transformations & PNG_INVERT_ALPHA) + png_do_read_invert_alpha(&(png_ptr->row_info), png_ptr->row_buf + 1); +#endif + +#ifdef PNG_READ_SWAP_ALPHA_SUPPORTED + if (png_ptr->transformations & PNG_SWAP_ALPHA) + png_do_read_swap_alpha(&(png_ptr->row_info), png_ptr->row_buf + 1); +#endif + +#ifdef PNG_READ_SWAP_SUPPORTED + if (png_ptr->transformations & PNG_SWAP_BYTES) + png_do_swap(&(png_ptr->row_info), png_ptr->row_buf + 1); +#endif + +#ifdef PNG_READ_USER_TRANSFORM_SUPPORTED + if (png_ptr->transformations & PNG_USER_TRANSFORM) + { + if (png_ptr->read_user_transform_fn != NULL) + (*(png_ptr->read_user_transform_fn)) /* User read transform function */ + (png_ptr, /* png_ptr */ + &(png_ptr->row_info), /* row_info: */ + /* png_uint_32 width; width of row */ + /* png_uint_32 rowbytes; number of bytes in row */ + /* png_byte color_type; color type of pixels */ + /* png_byte bit_depth; bit depth of samples */ + /* png_byte channels; number of channels (1-4) */ + /* png_byte pixel_depth; bits per pixel (depth*channels) */ + png_ptr->row_buf + 1); /* start of pixel data for row */ +#ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED + if (png_ptr->user_transform_depth) + png_ptr->row_info.bit_depth = png_ptr->user_transform_depth; + if (png_ptr->user_transform_channels) + png_ptr->row_info.channels = png_ptr->user_transform_channels; +#endif + png_ptr->row_info.pixel_depth = (png_byte)(png_ptr->row_info.bit_depth * + png_ptr->row_info.channels); + png_ptr->row_info.rowbytes = PNG_ROWBYTES(png_ptr->row_info.pixel_depth, + png_ptr->row_info.width); + } +#endif + +} + +#ifdef PNG_READ_PACK_SUPPORTED +/* Unpack pixels of 1, 2, or 4 bits per pixel into 1 byte per pixel, + * without changing the actual values. Thus, if you had a row with + * a bit depth of 1, you would end up with bytes that only contained + * the numbers 0 or 1. If you would rather they contain 0 and 255, use + * png_do_shift() after this. + */ +void /* PRIVATE */ +png_do_unpack(png_row_infop row_info, png_bytep row) +{ + png_debug(1, "in png_do_unpack"); + + if (row_info->bit_depth < 8) + { + png_uint_32 i; + png_uint_32 row_width=row_info->width; + + switch (row_info->bit_depth) + { + case 1: + { + png_bytep sp = row + (png_size_t)((row_width - 1) >> 3); + png_bytep dp = row + (png_size_t)row_width - 1; + png_uint_32 shift = 7 - (int)((row_width + 7) & 0x07); + for (i = 0; i < row_width; i++) + { + *dp = (png_byte)((*sp >> shift) & 0x01); + if (shift == 7) + { + shift = 0; + sp--; + } + else + shift++; + + dp--; + } + break; + } + + case 2: + { + + png_bytep sp = row + (png_size_t)((row_width - 1) >> 2); + png_bytep dp = row + (png_size_t)row_width - 1; + png_uint_32 shift = (int)((3 - ((row_width + 3) & 0x03)) << 1); + for (i = 0; i < row_width; i++) + { + *dp = (png_byte)((*sp >> shift) & 0x03); + if (shift == 6) + { + shift = 0; + sp--; + } + else + shift += 2; + + dp--; + } + break; + } + + case 4: + { + png_bytep sp = row + (png_size_t)((row_width - 1) >> 1); + png_bytep dp = row + (png_size_t)row_width - 1; + png_uint_32 shift = (int)((1 - ((row_width + 1) & 0x01)) << 2); + for (i = 0; i < row_width; i++) + { + *dp = (png_byte)((*sp >> shift) & 0x0f); + if (shift == 4) + { + shift = 0; + sp--; + } + else + shift = 4; + + dp--; + } + break; + } + } + row_info->bit_depth = 8; + row_info->pixel_depth = (png_byte)(8 * row_info->channels); + row_info->rowbytes = row_width * row_info->channels; + } +} +#endif + +#ifdef PNG_READ_SHIFT_SUPPORTED +/* Reverse the effects of png_do_shift. This routine merely shifts the + * pixels back to their significant bits values. Thus, if you have + * a row of bit depth 8, but only 5 are significant, this will shift + * the values back to 0 through 31. + */ +void /* PRIVATE */ +png_do_unshift(png_row_infop row_info, png_bytep row, png_color_8p sig_bits) +{ + png_debug(1, "in png_do_unshift"); + + if ( + row_info->color_type != PNG_COLOR_TYPE_PALETTE) + { + int shift[4]; + int channels = 0; + int c; + png_uint_16 value = 0; + png_uint_32 row_width = row_info->width; + + if (row_info->color_type & PNG_COLOR_MASK_COLOR) + { + shift[channels++] = row_info->bit_depth - sig_bits->red; + shift[channels++] = row_info->bit_depth - sig_bits->green; + shift[channels++] = row_info->bit_depth - sig_bits->blue; + } + else + { + shift[channels++] = row_info->bit_depth - sig_bits->gray; + } + if (row_info->color_type & PNG_COLOR_MASK_ALPHA) + { + shift[channels++] = row_info->bit_depth - sig_bits->alpha; + } + + for (c = 0; c < channels; c++) + { + if (shift[c] <= 0) + shift[c] = 0; + else + value = 1; + } + + if (!value) + return; + + switch (row_info->bit_depth) + { + case 2: + { + png_bytep bp; + png_uint_32 i; + png_uint_32 istop = row_info->rowbytes; + + for (bp = row, i = 0; i < istop; i++) + { + *bp >>= 1; + *bp++ &= 0x55; + } + break; + } + + case 4: + { + png_bytep bp = row; + png_uint_32 i; + png_uint_32 istop = row_info->rowbytes; + png_byte mask = (png_byte)((((int)0xf0 >> shift[0]) & (int)0xf0) | + (png_byte)((int)0xf >> shift[0])); + + for (i = 0; i < istop; i++) + { + *bp >>= shift[0]; + *bp++ &= mask; + } + break; + } + + case 8: + { + png_bytep bp = row; + png_uint_32 i; + png_uint_32 istop = row_width * channels; + + for (i = 0; i < istop; i++) + { + *bp++ >>= shift[i%channels]; + } + break; + } + + case 16: + { + png_bytep bp = row; + png_uint_32 i; + png_uint_32 istop = channels * row_width; + + for (i = 0; i < istop; i++) + { + value = (png_uint_16)((*bp << 8) + *(bp + 1)); + value >>= shift[i%channels]; + *bp++ = (png_byte)(value >> 8); + *bp++ = (png_byte)(value & 0xff); + } + break; + } + } + } +} +#endif + +#ifdef PNG_READ_16_TO_8_SUPPORTED +/* Chop rows of bit depth 16 down to 8 */ +void /* PRIVATE */ +png_do_chop(png_row_infop row_info, png_bytep row) +{ + png_debug(1, "in png_do_chop"); + + if (row_info->bit_depth == 16) + { + png_bytep sp = row; + png_bytep dp = row; + png_uint_32 i; + png_uint_32 istop = row_info->width * row_info->channels; + + for (i = 0; i> 8)) >> 8; + * + * Approximate calculation with shift/add instead of multiply/divide: + * *dp = ((((png_uint_32)(*sp) << 8) | + * (png_uint_32)((int)(*(sp + 1)) - *sp)) + 128) >> 8; + * + * What we actually do to avoid extra shifting and conversion: + */ + + *dp = *sp + ((((int)(*(sp + 1)) - *sp) > 128) ? 1 : 0); +#else + /* Simply discard the low order byte */ + *dp = *sp; +#endif + } + row_info->bit_depth = 8; + row_info->pixel_depth = (png_byte)(8 * row_info->channels); + row_info->rowbytes = row_info->width * row_info->channels; + } +} +#endif + +#ifdef PNG_READ_SWAP_ALPHA_SUPPORTED +void /* PRIVATE */ +png_do_read_swap_alpha(png_row_infop row_info, png_bytep row) +{ + png_debug(1, "in png_do_read_swap_alpha"); + + { + png_uint_32 row_width = row_info->width; + if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) + { + /* This converts from RGBA to ARGB */ + if (row_info->bit_depth == 8) + { + png_bytep sp = row + row_info->rowbytes; + png_bytep dp = sp; + png_byte save; + png_uint_32 i; + + for (i = 0; i < row_width; i++) + { + save = *(--sp); + *(--dp) = *(--sp); + *(--dp) = *(--sp); + *(--dp) = *(--sp); + *(--dp) = save; + } + } + /* This converts from RRGGBBAA to AARRGGBB */ + else + { + png_bytep sp = row + row_info->rowbytes; + png_bytep dp = sp; + png_byte save[2]; + png_uint_32 i; + + for (i = 0; i < row_width; i++) + { + save[0] = *(--sp); + save[1] = *(--sp); + *(--dp) = *(--sp); + *(--dp) = *(--sp); + *(--dp) = *(--sp); + *(--dp) = *(--sp); + *(--dp) = *(--sp); + *(--dp) = *(--sp); + *(--dp) = save[0]; + *(--dp) = save[1]; + } + } + } + else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA) + { + /* This converts from GA to AG */ + if (row_info->bit_depth == 8) + { + png_bytep sp = row + row_info->rowbytes; + png_bytep dp = sp; + png_byte save; + png_uint_32 i; + + for (i = 0; i < row_width; i++) + { + save = *(--sp); + *(--dp) = *(--sp); + *(--dp) = save; + } + } + /* This converts from GGAA to AAGG */ + else + { + png_bytep sp = row + row_info->rowbytes; + png_bytep dp = sp; + png_byte save[2]; + png_uint_32 i; + + for (i = 0; i < row_width; i++) + { + save[0] = *(--sp); + save[1] = *(--sp); + *(--dp) = *(--sp); + *(--dp) = *(--sp); + *(--dp) = save[0]; + *(--dp) = save[1]; + } + } + } + } +} +#endif + +#ifdef PNG_READ_INVERT_ALPHA_SUPPORTED +void /* PRIVATE */ +png_do_read_invert_alpha(png_row_infop row_info, png_bytep row) +{ + png_debug(1, "in png_do_read_invert_alpha"); + + { + png_uint_32 row_width = row_info->width; + if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) + { + /* This inverts the alpha channel in RGBA */ + if (row_info->bit_depth == 8) + { + png_bytep sp = row + row_info->rowbytes; + png_bytep dp = sp; + png_uint_32 i; + + for (i = 0; i < row_width; i++) + { + *(--dp) = (png_byte)(255 - *(--sp)); + +/* This does nothing: + *(--dp) = *(--sp); + *(--dp) = *(--sp); + *(--dp) = *(--sp); + We can replace it with: +*/ + sp-=3; + dp=sp; + } + } + /* This inverts the alpha channel in RRGGBBAA */ + else + { + png_bytep sp = row + row_info->rowbytes; + png_bytep dp = sp; + png_uint_32 i; + + for (i = 0; i < row_width; i++) + { + *(--dp) = (png_byte)(255 - *(--sp)); + *(--dp) = (png_byte)(255 - *(--sp)); + +/* This does nothing: + *(--dp) = *(--sp); + *(--dp) = *(--sp); + *(--dp) = *(--sp); + *(--dp) = *(--sp); + *(--dp) = *(--sp); + *(--dp) = *(--sp); + We can replace it with: +*/ + sp-=6; + dp=sp; + } + } + } + else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA) + { + /* This inverts the alpha channel in GA */ + if (row_info->bit_depth == 8) + { + png_bytep sp = row + row_info->rowbytes; + png_bytep dp = sp; + png_uint_32 i; + + for (i = 0; i < row_width; i++) + { + *(--dp) = (png_byte)(255 - *(--sp)); + *(--dp) = *(--sp); + } + } + /* This inverts the alpha channel in GGAA */ + else + { + png_bytep sp = row + row_info->rowbytes; + png_bytep dp = sp; + png_uint_32 i; + + for (i = 0; i < row_width; i++) + { + *(--dp) = (png_byte)(255 - *(--sp)); + *(--dp) = (png_byte)(255 - *(--sp)); +/* + *(--dp) = *(--sp); + *(--dp) = *(--sp); +*/ + sp-=2; + dp=sp; + } + } + } + } +} +#endif + +#ifdef PNG_READ_FILLER_SUPPORTED +/* Add filler channel if we have RGB color */ +void /* PRIVATE */ +png_do_read_filler(png_row_infop row_info, png_bytep row, + png_uint_32 filler, png_uint_32 flags) +{ + png_uint_32 i; + png_uint_32 row_width = row_info->width; + + png_byte hi_filler = (png_byte)((filler>>8) & 0xff); + png_byte lo_filler = (png_byte)(filler & 0xff); + + png_debug(1, "in png_do_read_filler"); + + if ( + row_info->color_type == PNG_COLOR_TYPE_GRAY) + { + if (row_info->bit_depth == 8) + { + /* This changes the data from G to GX */ + if (flags & PNG_FLAG_FILLER_AFTER) + { + png_bytep sp = row + (png_size_t)row_width; + png_bytep dp = sp + (png_size_t)row_width; + for (i = 1; i < row_width; i++) + { + *(--dp) = lo_filler; + *(--dp) = *(--sp); + } + *(--dp) = lo_filler; + row_info->channels = 2; + row_info->pixel_depth = 16; + row_info->rowbytes = row_width * 2; + } + /* This changes the data from G to XG */ + else + { + png_bytep sp = row + (png_size_t)row_width; + png_bytep dp = sp + (png_size_t)row_width; + for (i = 0; i < row_width; i++) + { + *(--dp) = *(--sp); + *(--dp) = lo_filler; + } + row_info->channels = 2; + row_info->pixel_depth = 16; + row_info->rowbytes = row_width * 2; + } + } + else if (row_info->bit_depth == 16) + { + /* This changes the data from GG to GGXX */ + if (flags & PNG_FLAG_FILLER_AFTER) + { + png_bytep sp = row + (png_size_t)row_width * 2; + png_bytep dp = sp + (png_size_t)row_width * 2; + for (i = 1; i < row_width; i++) + { + *(--dp) = hi_filler; + *(--dp) = lo_filler; + *(--dp) = *(--sp); + *(--dp) = *(--sp); + } + *(--dp) = hi_filler; + *(--dp) = lo_filler; + row_info->channels = 2; + row_info->pixel_depth = 32; + row_info->rowbytes = row_width * 4; + } + /* This changes the data from GG to XXGG */ + else + { + png_bytep sp = row + (png_size_t)row_width * 2; + png_bytep dp = sp + (png_size_t)row_width * 2; + for (i = 0; i < row_width; i++) + { + *(--dp) = *(--sp); + *(--dp) = *(--sp); + *(--dp) = hi_filler; + *(--dp) = lo_filler; + } + row_info->channels = 2; + row_info->pixel_depth = 32; + row_info->rowbytes = row_width * 4; + } + } + } /* COLOR_TYPE == GRAY */ + else if (row_info->color_type == PNG_COLOR_TYPE_RGB) + { + if (row_info->bit_depth == 8) + { + /* This changes the data from RGB to RGBX */ + if (flags & PNG_FLAG_FILLER_AFTER) + { + png_bytep sp = row + (png_size_t)row_width * 3; + png_bytep dp = sp + (png_size_t)row_width; + for (i = 1; i < row_width; i++) + { + *(--dp) = lo_filler; + *(--dp) = *(--sp); + *(--dp) = *(--sp); + *(--dp) = *(--sp); + } + *(--dp) = lo_filler; + row_info->channels = 4; + row_info->pixel_depth = 32; + row_info->rowbytes = row_width * 4; + } + /* This changes the data from RGB to XRGB */ + else + { + png_bytep sp = row + (png_size_t)row_width * 3; + png_bytep dp = sp + (png_size_t)row_width; + for (i = 0; i < row_width; i++) + { + *(--dp) = *(--sp); + *(--dp) = *(--sp); + *(--dp) = *(--sp); + *(--dp) = lo_filler; + } + row_info->channels = 4; + row_info->pixel_depth = 32; + row_info->rowbytes = row_width * 4; + } + } + else if (row_info->bit_depth == 16) + { + /* This changes the data from RRGGBB to RRGGBBXX */ + if (flags & PNG_FLAG_FILLER_AFTER) + { + png_bytep sp = row + (png_size_t)row_width * 6; + png_bytep dp = sp + (png_size_t)row_width * 2; + for (i = 1; i < row_width; i++) + { + *(--dp) = hi_filler; + *(--dp) = lo_filler; + *(--dp) = *(--sp); + *(--dp) = *(--sp); + *(--dp) = *(--sp); + *(--dp) = *(--sp); + *(--dp) = *(--sp); + *(--dp) = *(--sp); + } + *(--dp) = hi_filler; + *(--dp) = lo_filler; + row_info->channels = 4; + row_info->pixel_depth = 64; + row_info->rowbytes = row_width * 8; + } + /* This changes the data from RRGGBB to XXRRGGBB */ + else + { + png_bytep sp = row + (png_size_t)row_width * 6; + png_bytep dp = sp + (png_size_t)row_width * 2; + for (i = 0; i < row_width; i++) + { + *(--dp) = *(--sp); + *(--dp) = *(--sp); + *(--dp) = *(--sp); + *(--dp) = *(--sp); + *(--dp) = *(--sp); + *(--dp) = *(--sp); + *(--dp) = hi_filler; + *(--dp) = lo_filler; + } + row_info->channels = 4; + row_info->pixel_depth = 64; + row_info->rowbytes = row_width * 8; + } + } + } /* COLOR_TYPE == RGB */ +} +#endif + +#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED +/* Expand grayscale files to RGB, with or without alpha */ +void /* PRIVATE */ +png_do_gray_to_rgb(png_row_infop row_info, png_bytep row) +{ + png_uint_32 i; + png_uint_32 row_width = row_info->width; + + png_debug(1, "in png_do_gray_to_rgb"); + + if (row_info->bit_depth >= 8 && + !(row_info->color_type & PNG_COLOR_MASK_COLOR)) + { + if (row_info->color_type == PNG_COLOR_TYPE_GRAY) + { + if (row_info->bit_depth == 8) + { + png_bytep sp = row + (png_size_t)row_width - 1; + png_bytep dp = sp + (png_size_t)row_width * 2; + for (i = 0; i < row_width; i++) + { + *(dp--) = *sp; + *(dp--) = *sp; + *(dp--) = *(sp--); + } + } + else + { + png_bytep sp = row + (png_size_t)row_width * 2 - 1; + png_bytep dp = sp + (png_size_t)row_width * 4; + for (i = 0; i < row_width; i++) + { + *(dp--) = *sp; + *(dp--) = *(sp - 1); + *(dp--) = *sp; + *(dp--) = *(sp - 1); + *(dp--) = *(sp--); + *(dp--) = *(sp--); + } + } + } + else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA) + { + if (row_info->bit_depth == 8) + { + png_bytep sp = row + (png_size_t)row_width * 2 - 1; + png_bytep dp = sp + (png_size_t)row_width * 2; + for (i = 0; i < row_width; i++) + { + *(dp--) = *(sp--); + *(dp--) = *sp; + *(dp--) = *sp; + *(dp--) = *(sp--); + } + } + else + { + png_bytep sp = row + (png_size_t)row_width * 4 - 1; + png_bytep dp = sp + (png_size_t)row_width * 4; + for (i = 0; i < row_width; i++) + { + *(dp--) = *(sp--); + *(dp--) = *(sp--); + *(dp--) = *sp; + *(dp--) = *(sp - 1); + *(dp--) = *sp; + *(dp--) = *(sp - 1); + *(dp--) = *(sp--); + *(dp--) = *(sp--); + } + } + } + row_info->channels += (png_byte)2; + row_info->color_type |= PNG_COLOR_MASK_COLOR; + row_info->pixel_depth = (png_byte)(row_info->channels * + row_info->bit_depth); + row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth, row_width); + } +} +#endif + +#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED +/* Reduce RGB files to grayscale, with or without alpha + * using the equation given in Poynton's ColorFAQ at + * (THIS LINK IS DEAD June 2008) + * New link: + * + * Charles Poynton poynton at poynton.com + * + * Y = 0.212671 * R + 0.715160 * G + 0.072169 * B + * + * We approximate this with + * + * Y = 0.21268 * R + 0.7151 * G + 0.07217 * B + * + * which can be expressed with integers as + * + * Y = (6969 * R + 23434 * G + 2365 * B)/32768 + * + * The calculation is to be done in a linear colorspace. + * + * Other integer coefficents can be used via png_set_rgb_to_gray(). + */ +int /* PRIVATE */ +png_do_rgb_to_gray(png_structp png_ptr, png_row_infop row_info, png_bytep row) + +{ + png_uint_32 i; + + png_uint_32 row_width = row_info->width; + int rgb_error = 0; + + png_debug(1, "in png_do_rgb_to_gray"); + + if ( + (row_info->color_type & PNG_COLOR_MASK_COLOR)) + { + png_uint_32 rc = png_ptr->rgb_to_gray_red_coeff; + png_uint_32 gc = png_ptr->rgb_to_gray_green_coeff; + png_uint_32 bc = png_ptr->rgb_to_gray_blue_coeff; + + if (row_info->color_type == PNG_COLOR_TYPE_RGB) + { + if (row_info->bit_depth == 8) + { +#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) + if (png_ptr->gamma_from_1 != NULL && png_ptr->gamma_to_1 != NULL) + { + png_bytep sp = row; + png_bytep dp = row; + + for (i = 0; i < row_width; i++) + { + png_byte red = png_ptr->gamma_to_1[*(sp++)]; + png_byte green = png_ptr->gamma_to_1[*(sp++)]; + png_byte blue = png_ptr->gamma_to_1[*(sp++)]; + if (red != green || red != blue) + { + rgb_error |= 1; + *(dp++) = png_ptr->gamma_from_1[ + (rc*red + gc*green + bc*blue)>>15]; + } + else + *(dp++) = *(sp - 1); + } + } + else +#endif + { + png_bytep sp = row; + png_bytep dp = row; + for (i = 0; i < row_width; i++) + { + png_byte red = *(sp++); + png_byte green = *(sp++); + png_byte blue = *(sp++); + if (red != green || red != blue) + { + rgb_error |= 1; + *(dp++) = (png_byte)((rc*red + gc*green + bc*blue)>>15); + } + else + *(dp++) = *(sp - 1); + } + } + } + + else /* RGB bit_depth == 16 */ + { +#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) + if (png_ptr->gamma_16_to_1 != NULL && + png_ptr->gamma_16_from_1 != NULL) + { + png_bytep sp = row; + png_bytep dp = row; + for (i = 0; i < row_width; i++) + { + png_uint_16 red, green, blue, w; + + red = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2; + green = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2; + blue = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2; + + if (red == green && red == blue) + w = red; + else + { + png_uint_16 red_1 = png_ptr->gamma_16_to_1[(red&0xff) >> + png_ptr->gamma_shift][red>>8]; + png_uint_16 green_1 = + png_ptr->gamma_16_to_1[(green&0xff) >> + png_ptr->gamma_shift][green>>8]; + png_uint_16 blue_1 = png_ptr->gamma_16_to_1[(blue&0xff) >> + png_ptr->gamma_shift][blue>>8]; + png_uint_16 gray16 = (png_uint_16)((rc*red_1 + gc*green_1 + + bc*blue_1)>>15); + w = png_ptr->gamma_16_from_1[(gray16&0xff) >> + png_ptr->gamma_shift][gray16 >> 8]; + rgb_error |= 1; + } + + *(dp++) = (png_byte)((w>>8) & 0xff); + *(dp++) = (png_byte)(w & 0xff); + } + } + else +#endif + { + png_bytep sp = row; + png_bytep dp = row; + for (i = 0; i < row_width; i++) + { + png_uint_16 red, green, blue, gray16; + + red = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2; + green = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2; + blue = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2; + + if (red != green || red != blue) + rgb_error |= 1; + gray16 = (png_uint_16)((rc*red + gc*green + bc*blue)>>15); + *(dp++) = (png_byte)((gray16>>8) & 0xff); + *(dp++) = (png_byte)(gray16 & 0xff); + } + } + } + } + if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) + { + if (row_info->bit_depth == 8) + { +#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) + if (png_ptr->gamma_from_1 != NULL && png_ptr->gamma_to_1 != NULL) + { + png_bytep sp = row; + png_bytep dp = row; + for (i = 0; i < row_width; i++) + { + png_byte red = png_ptr->gamma_to_1[*(sp++)]; + png_byte green = png_ptr->gamma_to_1[*(sp++)]; + png_byte blue = png_ptr->gamma_to_1[*(sp++)]; + if (red != green || red != blue) + rgb_error |= 1; + *(dp++) = png_ptr->gamma_from_1 + [(rc*red + gc*green + bc*blue)>>15]; + *(dp++) = *(sp++); /* alpha */ + } + } + else +#endif + { + png_bytep sp = row; + png_bytep dp = row; + for (i = 0; i < row_width; i++) + { + png_byte red = *(sp++); + png_byte green = *(sp++); + png_byte blue = *(sp++); + if (red != green || red != blue) + rgb_error |= 1; + *(dp++) = (png_byte)((rc*red + gc*green + bc*blue)>>15); + *(dp++) = *(sp++); /* alpha */ + } + } + } + else /* RGBA bit_depth == 16 */ + { +#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) + if (png_ptr->gamma_16_to_1 != NULL && + png_ptr->gamma_16_from_1 != NULL) + { + png_bytep sp = row; + png_bytep dp = row; + for (i = 0; i < row_width; i++) + { + png_uint_16 red, green, blue, w; + + red = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2; + green = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2; + blue = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2; + + if (red == green && red == blue) + w = red; + else + { + png_uint_16 red_1 = png_ptr->gamma_16_to_1[(red&0xff) >> + png_ptr->gamma_shift][red>>8]; + png_uint_16 green_1 = + png_ptr->gamma_16_to_1[(green&0xff) >> + png_ptr->gamma_shift][green>>8]; + png_uint_16 blue_1 = png_ptr->gamma_16_to_1[(blue&0xff) >> + png_ptr->gamma_shift][blue>>8]; + png_uint_16 gray16 = (png_uint_16)((rc * red_1 + + gc * green_1 + bc * blue_1)>>15); + w = png_ptr->gamma_16_from_1[(gray16&0xff) >> + png_ptr->gamma_shift][gray16 >> 8]; + rgb_error |= 1; + } + + *(dp++) = (png_byte)((w>>8) & 0xff); + *(dp++) = (png_byte)(w & 0xff); + *(dp++) = *(sp++); /* alpha */ + *(dp++) = *(sp++); + } + } + else +#endif + { + png_bytep sp = row; + png_bytep dp = row; + for (i = 0; i < row_width; i++) + { + png_uint_16 red, green, blue, gray16; + red = (png_uint_16)((*(sp)<<8) | *(sp+1)); sp+=2; + green = (png_uint_16)((*(sp)<<8) | *(sp+1)); sp+=2; + blue = (png_uint_16)((*(sp)<<8) | *(sp+1)); sp+=2; + if (red != green || red != blue) + rgb_error |= 1; + gray16 = (png_uint_16)((rc*red + gc*green + bc*blue)>>15); + *(dp++) = (png_byte)((gray16>>8) & 0xff); + *(dp++) = (png_byte)(gray16 & 0xff); + *(dp++) = *(sp++); /* alpha */ + *(dp++) = *(sp++); + } + } + } + } + row_info->channels -= (png_byte)2; + row_info->color_type &= ~PNG_COLOR_MASK_COLOR; + row_info->pixel_depth = (png_byte)(row_info->channels * + row_info->bit_depth); + row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth, row_width); + } + return rgb_error; +} +#endif + +/* Build a grayscale palette. Palette is assumed to be 1 << bit_depth + * large of png_color. This lets grayscale images be treated as + * paletted. Most useful for gamma correction and simplification + * of code. + */ +void PNGAPI +png_build_grayscale_palette(int bit_depth, png_colorp palette) +{ + int num_palette; + int color_inc; + int i; + int v; + + png_debug(1, "in png_do_build_grayscale_palette"); + + if (palette == NULL) + return; + + switch (bit_depth) + { + case 1: + num_palette = 2; + color_inc = 0xff; + break; + + case 2: + num_palette = 4; + color_inc = 0x55; + break; + + case 4: + num_palette = 16; + color_inc = 0x11; + break; + + case 8: + num_palette = 256; + color_inc = 1; + break; + + default: + num_palette = 0; + color_inc = 0; + break; + } + + for (i = 0, v = 0; i < num_palette; i++, v += color_inc) + { + palette[i].red = (png_byte)v; + palette[i].green = (png_byte)v; + palette[i].blue = (png_byte)v; + } +} + + +#ifdef PNG_READ_BACKGROUND_SUPPORTED +/* Replace any alpha or transparency with the supplied background color. + * "background" is already in the screen gamma, while "background_1" is + * at a gamma of 1.0. Paletted files have already been taken care of. + */ +void /* PRIVATE */ +png_do_background(png_row_infop row_info, png_bytep row, + png_color_16p trans_color, png_color_16p background +#ifdef PNG_READ_GAMMA_SUPPORTED + , png_color_16p background_1, + png_bytep gamma_table, png_bytep gamma_from_1, png_bytep gamma_to_1, + png_uint_16pp gamma_16, png_uint_16pp gamma_16_from_1, + png_uint_16pp gamma_16_to_1, int gamma_shift +#endif + ) +{ + png_bytep sp, dp; + png_uint_32 i; + png_uint_32 row_width=row_info->width; + int shift; + + png_debug(1, "in png_do_background"); + + if (background != NULL && + (!(row_info->color_type & PNG_COLOR_MASK_ALPHA) || + (row_info->color_type != PNG_COLOR_TYPE_PALETTE && trans_color))) + { + switch (row_info->color_type) + { + case PNG_COLOR_TYPE_GRAY: + { + switch (row_info->bit_depth) + { + case 1: + { + sp = row; + shift = 7; + for (i = 0; i < row_width; i++) + { + if ((png_uint_16)((*sp >> shift) & 0x01) + == trans_color->gray) + { + *sp &= (png_byte)((0x7f7f >> (7 - shift)) & 0xff); + *sp |= (png_byte)(background->gray << shift); + } + if (!shift) + { + shift = 7; + sp++; + } + else + shift--; + } + break; + } + + case 2: + { +#ifdef PNG_READ_GAMMA_SUPPORTED + if (gamma_table != NULL) + { + sp = row; + shift = 6; + for (i = 0; i < row_width; i++) + { + if ((png_uint_16)((*sp >> shift) & 0x03) + == trans_color->gray) + { + *sp &= (png_byte)((0x3f3f >> (6 - shift)) & 0xff); + *sp |= (png_byte)(background->gray << shift); + } + else + { + png_byte p = (png_byte)((*sp >> shift) & 0x03); + png_byte g = (png_byte)((gamma_table [p | (p << 2) | + (p << 4) | (p << 6)] >> 6) & 0x03); + *sp &= (png_byte)((0x3f3f >> (6 - shift)) & 0xff); + *sp |= (png_byte)(g << shift); + } + if (!shift) + { + shift = 6; + sp++; + } + else + shift -= 2; + } + } + else +#endif + { + sp = row; + shift = 6; + for (i = 0; i < row_width; i++) + { + if ((png_uint_16)((*sp >> shift) & 0x03) + == trans_color->gray) + { + *sp &= (png_byte)((0x3f3f >> (6 - shift)) & 0xff); + *sp |= (png_byte)(background->gray << shift); + } + if (!shift) + { + shift = 6; + sp++; + } + else + shift -= 2; + } + } + break; + } + + case 4: + { +#ifdef PNG_READ_GAMMA_SUPPORTED + if (gamma_table != NULL) + { + sp = row; + shift = 4; + for (i = 0; i < row_width; i++) + { + if ((png_uint_16)((*sp >> shift) & 0x0f) + == trans_color->gray) + { + *sp &= (png_byte)((0xf0f >> (4 - shift)) & 0xff); + *sp |= (png_byte)(background->gray << shift); + } + else + { + png_byte p = (png_byte)((*sp >> shift) & 0x0f); + png_byte g = (png_byte)((gamma_table[p | + (p << 4)] >> 4) & 0x0f); + *sp &= (png_byte)((0xf0f >> (4 - shift)) & 0xff); + *sp |= (png_byte)(g << shift); + } + if (!shift) + { + shift = 4; + sp++; + } + else + shift -= 4; + } + } + else +#endif + { + sp = row; + shift = 4; + for (i = 0; i < row_width; i++) + { + if ((png_uint_16)((*sp >> shift) & 0x0f) + == trans_color->gray) + { + *sp &= (png_byte)((0xf0f >> (4 - shift)) & 0xff); + *sp |= (png_byte)(background->gray << shift); + } + if (!shift) + { + shift = 4; + sp++; + } + else + shift -= 4; + } + } + break; + } + + case 8: + { +#ifdef PNG_READ_GAMMA_SUPPORTED + if (gamma_table != NULL) + { + sp = row; + for (i = 0; i < row_width; i++, sp++) + { + if (*sp == trans_color->gray) + { + *sp = (png_byte)background->gray; + } + else + { + *sp = gamma_table[*sp]; + } + } + } + else +#endif + { + sp = row; + for (i = 0; i < row_width; i++, sp++) + { + if (*sp == trans_color->gray) + { + *sp = (png_byte)background->gray; + } + } + } + break; + } + + case 16: + { +#ifdef PNG_READ_GAMMA_SUPPORTED + if (gamma_16 != NULL) + { + sp = row; + for (i = 0; i < row_width; i++, sp += 2) + { + png_uint_16 v; + + v = (png_uint_16)(((*sp) << 8) + *(sp + 1)); + if (v == trans_color->gray) + { + /* Background is already in screen gamma */ + *sp = (png_byte)((background->gray >> 8) & 0xff); + *(sp + 1) = (png_byte)(background->gray & 0xff); + } + else + { + v = gamma_16[*(sp + 1) >> gamma_shift][*sp]; + *sp = (png_byte)((v >> 8) & 0xff); + *(sp + 1) = (png_byte)(v & 0xff); + } + } + } + else +#endif + { + sp = row; + for (i = 0; i < row_width; i++, sp += 2) + { + png_uint_16 v; + + v = (png_uint_16)(((*sp) << 8) + *(sp + 1)); + if (v == trans_color->gray) + { + *sp = (png_byte)((background->gray >> 8) & 0xff); + *(sp + 1) = (png_byte)(background->gray & 0xff); + } + } + } + break; + } + } + break; + } + + case PNG_COLOR_TYPE_RGB: + { + if (row_info->bit_depth == 8) + { +#ifdef PNG_READ_GAMMA_SUPPORTED + if (gamma_table != NULL) + { + sp = row; + for (i = 0; i < row_width; i++, sp += 3) + { + if (*sp == trans_color->red && + *(sp + 1) == trans_color->green && + *(sp + 2) == trans_color->blue) + { + *sp = (png_byte)background->red; + *(sp + 1) = (png_byte)background->green; + *(sp + 2) = (png_byte)background->blue; + } + else + { + *sp = gamma_table[*sp]; + *(sp + 1) = gamma_table[*(sp + 1)]; + *(sp + 2) = gamma_table[*(sp + 2)]; + } + } + } + else +#endif + { + sp = row; + for (i = 0; i < row_width; i++, sp += 3) + { + if (*sp == trans_color->red && + *(sp + 1) == trans_color->green && + *(sp + 2) == trans_color->blue) + { + *sp = (png_byte)background->red; + *(sp + 1) = (png_byte)background->green; + *(sp + 2) = (png_byte)background->blue; + } + } + } + } + else /* if (row_info->bit_depth == 16) */ + { +#ifdef PNG_READ_GAMMA_SUPPORTED + if (gamma_16 != NULL) + { + sp = row; + for (i = 0; i < row_width; i++, sp += 6) + { + png_uint_16 r = (png_uint_16)(((*sp) << 8) + *(sp + 1)); + png_uint_16 g = (png_uint_16)(((*(sp+2)) << 8) + *(sp+3)); + png_uint_16 b = (png_uint_16)(((*(sp+4)) << 8) + *(sp+5)); + if (r == trans_color->red && g == trans_color->green && + b == trans_color->blue) + { + /* Background is already in screen gamma */ + *sp = (png_byte)((background->red >> 8) & 0xff); + *(sp + 1) = (png_byte)(background->red & 0xff); + *(sp + 2) = (png_byte)((background->green >> 8) & 0xff); + *(sp + 3) = (png_byte)(background->green & 0xff); + *(sp + 4) = (png_byte)((background->blue >> 8) & 0xff); + *(sp + 5) = (png_byte)(background->blue & 0xff); + } + else + { + png_uint_16 v = gamma_16[*(sp + 1) >> gamma_shift][*sp]; + *sp = (png_byte)((v >> 8) & 0xff); + *(sp + 1) = (png_byte)(v & 0xff); + v = gamma_16[*(sp + 3) >> gamma_shift][*(sp + 2)]; + *(sp + 2) = (png_byte)((v >> 8) & 0xff); + *(sp + 3) = (png_byte)(v & 0xff); + v = gamma_16[*(sp + 5) >> gamma_shift][*(sp + 4)]; + *(sp + 4) = (png_byte)((v >> 8) & 0xff); + *(sp + 5) = (png_byte)(v & 0xff); + } + } + } + else +#endif + { + sp = row; + for (i = 0; i < row_width; i++, sp += 6) + { + png_uint_16 r = (png_uint_16)(((*sp) << 8) + *(sp+1)); + png_uint_16 g = (png_uint_16)(((*(sp+2)) << 8) + *(sp+3)); + png_uint_16 b = (png_uint_16)(((*(sp+4)) << 8) + *(sp+5)); + + if (r == trans_color->red && g == trans_color->green && + b == trans_color->blue) + { + *sp = (png_byte)((background->red >> 8) & 0xff); + *(sp + 1) = (png_byte)(background->red & 0xff); + *(sp + 2) = (png_byte)((background->green >> 8) & 0xff); + *(sp + 3) = (png_byte)(background->green & 0xff); + *(sp + 4) = (png_byte)((background->blue >> 8) & 0xff); + *(sp + 5) = (png_byte)(background->blue & 0xff); + } + } + } + } + break; + } + + case PNG_COLOR_TYPE_GRAY_ALPHA: + { + if (row_info->bit_depth == 8) + { +#ifdef PNG_READ_GAMMA_SUPPORTED + if (gamma_to_1 != NULL && gamma_from_1 != NULL && + gamma_table != NULL) + { + sp = row; + dp = row; + for (i = 0; i < row_width; i++, sp += 2, dp++) + { + png_uint_16 a = *(sp + 1); + + if (a == 0xff) + { + *dp = gamma_table[*sp]; + } + else if (a == 0) + { + /* Background is already in screen gamma */ + *dp = (png_byte)background->gray; + } + else + { + png_byte v, w; + + v = gamma_to_1[*sp]; + png_composite(w, v, a, background_1->gray); + *dp = gamma_from_1[w]; + } + } + } + else +#endif + { + sp = row; + dp = row; + for (i = 0; i < row_width; i++, sp += 2, dp++) + { + png_byte a = *(sp + 1); + + if (a == 0xff) + { + *dp = *sp; + } +#ifdef PNG_READ_GAMMA_SUPPORTED + else if (a == 0) + { + *dp = (png_byte)background->gray; + } + else + { + png_composite(*dp, *sp, a, background_1->gray); + } +#else + *dp = (png_byte)background->gray; +#endif + } + } + } + else /* if (png_ptr->bit_depth == 16) */ + { +#ifdef PNG_READ_GAMMA_SUPPORTED + if (gamma_16 != NULL && gamma_16_from_1 != NULL && + gamma_16_to_1 != NULL) + { + sp = row; + dp = row; + for (i = 0; i < row_width; i++, sp += 4, dp += 2) + { + png_uint_16 a = (png_uint_16)(((*(sp+2)) << 8) + *(sp+3)); + + if (a == (png_uint_16)0xffff) + { + png_uint_16 v; + + v = gamma_16[*(sp + 1) >> gamma_shift][*sp]; + *dp = (png_byte)((v >> 8) & 0xff); + *(dp + 1) = (png_byte)(v & 0xff); + } +#ifdef PNG_READ_GAMMA_SUPPORTED + else if (a == 0) +#else + else +#endif + { + /* Background is already in screen gamma */ + *dp = (png_byte)((background->gray >> 8) & 0xff); + *(dp + 1) = (png_byte)(background->gray & 0xff); + } +#ifdef PNG_READ_GAMMA_SUPPORTED + else + { + png_uint_16 g, v, w; + + g = gamma_16_to_1[*(sp + 1) >> gamma_shift][*sp]; + png_composite_16(v, g, a, background_1->gray); + w = gamma_16_from_1[(v&0xff) >> gamma_shift][v >> 8]; + *dp = (png_byte)((w >> 8) & 0xff); + *(dp + 1) = (png_byte)(w & 0xff); + } +#endif + } + } + else +#endif + { + sp = row; + dp = row; + for (i = 0; i < row_width; i++, sp += 4, dp += 2) + { + png_uint_16 a = (png_uint_16)(((*(sp+2)) << 8) + *(sp+3)); + if (a == (png_uint_16)0xffff) + { + png_memcpy(dp, sp, 2); + } +#ifdef PNG_READ_GAMMA_SUPPORTED + else if (a == 0) +#else + else +#endif + { + *dp = (png_byte)((background->gray >> 8) & 0xff); + *(dp + 1) = (png_byte)(background->gray & 0xff); + } +#ifdef PNG_READ_GAMMA_SUPPORTED + else + { + png_uint_16 g, v; + + g = (png_uint_16)(((*sp) << 8) + *(sp + 1)); + png_composite_16(v, g, a, background_1->gray); + *dp = (png_byte)((v >> 8) & 0xff); + *(dp + 1) = (png_byte)(v & 0xff); + } +#endif + } + } + } + break; + } + + case PNG_COLOR_TYPE_RGB_ALPHA: + { + if (row_info->bit_depth == 8) + { +#ifdef PNG_READ_GAMMA_SUPPORTED + if (gamma_to_1 != NULL && gamma_from_1 != NULL && + gamma_table != NULL) + { + sp = row; + dp = row; + for (i = 0; i < row_width; i++, sp += 4, dp += 3) + { + png_byte a = *(sp + 3); + + if (a == 0xff) + { + *dp = gamma_table[*sp]; + *(dp + 1) = gamma_table[*(sp + 1)]; + *(dp + 2) = gamma_table[*(sp + 2)]; + } + else if (a == 0) + { + /* Background is already in screen gamma */ + *dp = (png_byte)background->red; + *(dp + 1) = (png_byte)background->green; + *(dp + 2) = (png_byte)background->blue; + } + else + { + png_byte v, w; + + v = gamma_to_1[*sp]; + png_composite(w, v, a, background_1->red); + *dp = gamma_from_1[w]; + v = gamma_to_1[*(sp + 1)]; + png_composite(w, v, a, background_1->green); + *(dp + 1) = gamma_from_1[w]; + v = gamma_to_1[*(sp + 2)]; + png_composite(w, v, a, background_1->blue); + *(dp + 2) = gamma_from_1[w]; + } + } + } + else +#endif + { + sp = row; + dp = row; + for (i = 0; i < row_width; i++, sp += 4, dp += 3) + { + png_byte a = *(sp + 3); + + if (a == 0xff) + { + *dp = *sp; + *(dp + 1) = *(sp + 1); + *(dp + 2) = *(sp + 2); + } + else if (a == 0) + { + *dp = (png_byte)background->red; + *(dp + 1) = (png_byte)background->green; + *(dp + 2) = (png_byte)background->blue; + } + else + { + png_composite(*dp, *sp, a, background->red); + png_composite(*(dp + 1), *(sp + 1), a, + background->green); + png_composite(*(dp + 2), *(sp + 2), a, + background->blue); + } + } + } + } + else /* if (row_info->bit_depth == 16) */ + { +#ifdef PNG_READ_GAMMA_SUPPORTED + if (gamma_16 != NULL && gamma_16_from_1 != NULL && + gamma_16_to_1 != NULL) + { + sp = row; + dp = row; + for (i = 0; i < row_width; i++, sp += 8, dp += 6) + { + png_uint_16 a = (png_uint_16)(((png_uint_16)(*(sp + 6)) + << 8) + (png_uint_16)(*(sp + 7))); + if (a == (png_uint_16)0xffff) + { + png_uint_16 v; + + v = gamma_16[*(sp + 1) >> gamma_shift][*sp]; + *dp = (png_byte)((v >> 8) & 0xff); + *(dp + 1) = (png_byte)(v & 0xff); + v = gamma_16[*(sp + 3) >> gamma_shift][*(sp + 2)]; + *(dp + 2) = (png_byte)((v >> 8) & 0xff); + *(dp + 3) = (png_byte)(v & 0xff); + v = gamma_16[*(sp + 5) >> gamma_shift][*(sp + 4)]; + *(dp + 4) = (png_byte)((v >> 8) & 0xff); + *(dp + 5) = (png_byte)(v & 0xff); + } + else if (a == 0) + { + /* Background is already in screen gamma */ + *dp = (png_byte)((background->red >> 8) & 0xff); + *(dp + 1) = (png_byte)(background->red & 0xff); + *(dp + 2) = (png_byte)((background->green >> 8) & 0xff); + *(dp + 3) = (png_byte)(background->green & 0xff); + *(dp + 4) = (png_byte)((background->blue >> 8) & 0xff); + *(dp + 5) = (png_byte)(background->blue & 0xff); + } + else + { + png_uint_16 v, w, x; + + v = gamma_16_to_1[*(sp + 1) >> gamma_shift][*sp]; + png_composite_16(w, v, a, background_1->red); + x = gamma_16_from_1[((w&0xff) >> gamma_shift)][w >> 8]; + *dp = (png_byte)((x >> 8) & 0xff); + *(dp + 1) = (png_byte)(x & 0xff); + v = gamma_16_to_1[*(sp + 3) >> gamma_shift][*(sp + 2)]; + png_composite_16(w, v, a, background_1->green); + x = gamma_16_from_1[((w&0xff) >> gamma_shift)][w >> 8]; + *(dp + 2) = (png_byte)((x >> 8) & 0xff); + *(dp + 3) = (png_byte)(x & 0xff); + v = gamma_16_to_1[*(sp + 5) >> gamma_shift][*(sp + 4)]; + png_composite_16(w, v, a, background_1->blue); + x = gamma_16_from_1[(w & 0xff) >> gamma_shift][w >> 8]; + *(dp + 4) = (png_byte)((x >> 8) & 0xff); + *(dp + 5) = (png_byte)(x & 0xff); + } + } + } + else +#endif + { + sp = row; + dp = row; + for (i = 0; i < row_width; i++, sp += 8, dp += 6) + { + png_uint_16 a = (png_uint_16)(((png_uint_16)(*(sp + 6)) + << 8) + (png_uint_16)(*(sp + 7))); + if (a == (png_uint_16)0xffff) + { + png_memcpy(dp, sp, 6); + } + else if (a == 0) + { + *dp = (png_byte)((background->red >> 8) & 0xff); + *(dp + 1) = (png_byte)(background->red & 0xff); + *(dp + 2) = (png_byte)((background->green >> 8) & 0xff); + *(dp + 3) = (png_byte)(background->green & 0xff); + *(dp + 4) = (png_byte)((background->blue >> 8) & 0xff); + *(dp + 5) = (png_byte)(background->blue & 0xff); + } + else + { + png_uint_16 v; + + png_uint_16 r = (png_uint_16)(((*sp) << 8) + *(sp + 1)); + png_uint_16 g = (png_uint_16)(((*(sp + 2)) << 8) + + *(sp + 3)); + png_uint_16 b = (png_uint_16)(((*(sp + 4)) << 8) + + *(sp + 5)); + + png_composite_16(v, r, a, background->red); + *dp = (png_byte)((v >> 8) & 0xff); + *(dp + 1) = (png_byte)(v & 0xff); + png_composite_16(v, g, a, background->green); + *(dp + 2) = (png_byte)((v >> 8) & 0xff); + *(dp + 3) = (png_byte)(v & 0xff); + png_composite_16(v, b, a, background->blue); + *(dp + 4) = (png_byte)((v >> 8) & 0xff); + *(dp + 5) = (png_byte)(v & 0xff); + } + } + } + } + break; + } + } + + if (row_info->color_type & PNG_COLOR_MASK_ALPHA) + { + row_info->color_type &= ~PNG_COLOR_MASK_ALPHA; + row_info->channels--; + row_info->pixel_depth = (png_byte)(row_info->channels * + row_info->bit_depth); + row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth, row_width); + } + } +} +#endif + +#ifdef PNG_READ_GAMMA_SUPPORTED +/* Gamma correct the image, avoiding the alpha channel. Make sure + * you do this after you deal with the transparency issue on grayscale + * or RGB images. If your bit depth is 8, use gamma_table, if it + * is 16, use gamma_16_table and gamma_shift. Build these with + * build_gamma_table(). + */ +void /* PRIVATE */ +png_do_gamma(png_row_infop row_info, png_bytep row, + png_bytep gamma_table, png_uint_16pp gamma_16_table, + int gamma_shift) +{ + png_bytep sp; + png_uint_32 i; + png_uint_32 row_width=row_info->width; + + png_debug(1, "in png_do_gamma"); + + if ( + ((row_info->bit_depth <= 8 && gamma_table != NULL) || + (row_info->bit_depth == 16 && gamma_16_table != NULL))) + { + switch (row_info->color_type) + { + case PNG_COLOR_TYPE_RGB: + { + if (row_info->bit_depth == 8) + { + sp = row; + for (i = 0; i < row_width; i++) + { + *sp = gamma_table[*sp]; + sp++; + *sp = gamma_table[*sp]; + sp++; + *sp = gamma_table[*sp]; + sp++; + } + } + else /* if (row_info->bit_depth == 16) */ + { + sp = row; + for (i = 0; i < row_width; i++) + { + png_uint_16 v; + + v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp]; + *sp = (png_byte)((v >> 8) & 0xff); + *(sp + 1) = (png_byte)(v & 0xff); + sp += 2; + v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp]; + *sp = (png_byte)((v >> 8) & 0xff); + *(sp + 1) = (png_byte)(v & 0xff); + sp += 2; + v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp]; + *sp = (png_byte)((v >> 8) & 0xff); + *(sp + 1) = (png_byte)(v & 0xff); + sp += 2; + } + } + break; + } + + case PNG_COLOR_TYPE_RGB_ALPHA: + { + if (row_info->bit_depth == 8) + { + sp = row; + for (i = 0; i < row_width; i++) + { + *sp = gamma_table[*sp]; + sp++; + *sp = gamma_table[*sp]; + sp++; + *sp = gamma_table[*sp]; + sp++; + sp++; + } + } + else /* if (row_info->bit_depth == 16) */ + { + sp = row; + for (i = 0; i < row_width; i++) + { + png_uint_16 v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp]; + *sp = (png_byte)((v >> 8) & 0xff); + *(sp + 1) = (png_byte)(v & 0xff); + sp += 2; + v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp]; + *sp = (png_byte)((v >> 8) & 0xff); + *(sp + 1) = (png_byte)(v & 0xff); + sp += 2; + v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp]; + *sp = (png_byte)((v >> 8) & 0xff); + *(sp + 1) = (png_byte)(v & 0xff); + sp += 4; + } + } + break; + } + + case PNG_COLOR_TYPE_GRAY_ALPHA: + { + if (row_info->bit_depth == 8) + { + sp = row; + for (i = 0; i < row_width; i++) + { + *sp = gamma_table[*sp]; + sp += 2; + } + } + else /* if (row_info->bit_depth == 16) */ + { + sp = row; + for (i = 0; i < row_width; i++) + { + png_uint_16 v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp]; + *sp = (png_byte)((v >> 8) & 0xff); + *(sp + 1) = (png_byte)(v & 0xff); + sp += 4; + } + } + break; + } + + case PNG_COLOR_TYPE_GRAY: + { + if (row_info->bit_depth == 2) + { + sp = row; + for (i = 0; i < row_width; i += 4) + { + int a = *sp & 0xc0; + int b = *sp & 0x30; + int c = *sp & 0x0c; + int d = *sp & 0x03; + + *sp = (png_byte)( + ((((int)gamma_table[a|(a>>2)|(a>>4)|(a>>6)]) ) & 0xc0)| + ((((int)gamma_table[(b<<2)|b|(b>>2)|(b>>4)])>>2) & 0x30)| + ((((int)gamma_table[(c<<4)|(c<<2)|c|(c>>2)])>>4) & 0x0c)| + ((((int)gamma_table[(d<<6)|(d<<4)|(d<<2)|d])>>6) )); + sp++; + } + } + + if (row_info->bit_depth == 4) + { + sp = row; + for (i = 0; i < row_width; i += 2) + { + int msb = *sp & 0xf0; + int lsb = *sp & 0x0f; + + *sp = (png_byte)((((int)gamma_table[msb | (msb >> 4)]) & 0xf0) + | (((int)gamma_table[(lsb << 4) | lsb]) >> 4)); + sp++; + } + } + + else if (row_info->bit_depth == 8) + { + sp = row; + for (i = 0; i < row_width; i++) + { + *sp = gamma_table[*sp]; + sp++; + } + } + + else if (row_info->bit_depth == 16) + { + sp = row; + for (i = 0; i < row_width; i++) + { + png_uint_16 v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp]; + *sp = (png_byte)((v >> 8) & 0xff); + *(sp + 1) = (png_byte)(v & 0xff); + sp += 2; + } + } + break; + } + } + } +} +#endif + +#ifdef PNG_READ_EXPAND_SUPPORTED +/* Expands a palette row to an RGB or RGBA row depending + * upon whether you supply trans and num_trans. + */ +void /* PRIVATE */ +png_do_expand_palette(png_row_infop row_info, png_bytep row, + png_colorp palette, png_bytep trans_alpha, int num_trans) +{ + int shift, value; + png_bytep sp, dp; + png_uint_32 i; + png_uint_32 row_width=row_info->width; + + png_debug(1, "in png_do_expand_palette"); + + if ( + row_info->color_type == PNG_COLOR_TYPE_PALETTE) + { + if (row_info->bit_depth < 8) + { + switch (row_info->bit_depth) + { + case 1: + { + sp = row + (png_size_t)((row_width - 1) >> 3); + dp = row + (png_size_t)row_width - 1; + shift = 7 - (int)((row_width + 7) & 0x07); + for (i = 0; i < row_width; i++) + { + if ((*sp >> shift) & 0x01) + *dp = 1; + else + *dp = 0; + if (shift == 7) + { + shift = 0; + sp--; + } + else + shift++; + + dp--; + } + break; + } + + case 2: + { + sp = row + (png_size_t)((row_width - 1) >> 2); + dp = row + (png_size_t)row_width - 1; + shift = (int)((3 - ((row_width + 3) & 0x03)) << 1); + for (i = 0; i < row_width; i++) + { + value = (*sp >> shift) & 0x03; + *dp = (png_byte)value; + if (shift == 6) + { + shift = 0; + sp--; + } + else + shift += 2; + + dp--; + } + break; + } + + case 4: + { + sp = row + (png_size_t)((row_width - 1) >> 1); + dp = row + (png_size_t)row_width - 1; + shift = (int)((row_width & 0x01) << 2); + for (i = 0; i < row_width; i++) + { + value = (*sp >> shift) & 0x0f; + *dp = (png_byte)value; + if (shift == 4) + { + shift = 0; + sp--; + } + else + shift += 4; + + dp--; + } + break; + } + } + row_info->bit_depth = 8; + row_info->pixel_depth = 8; + row_info->rowbytes = row_width; + } + switch (row_info->bit_depth) + { + case 8: + { + if (trans_alpha != NULL) + { + sp = row + (png_size_t)row_width - 1; + dp = row + (png_size_t)(row_width << 2) - 1; + + for (i = 0; i < row_width; i++) + { + if ((int)(*sp) >= num_trans) + *dp-- = 0xff; + else + *dp-- = trans_alpha[*sp]; + *dp-- = palette[*sp].blue; + *dp-- = palette[*sp].green; + *dp-- = palette[*sp].red; + sp--; + } + row_info->bit_depth = 8; + row_info->pixel_depth = 32; + row_info->rowbytes = row_width * 4; + row_info->color_type = 6; + row_info->channels = 4; + } + else + { + sp = row + (png_size_t)row_width - 1; + dp = row + (png_size_t)(row_width * 3) - 1; + + for (i = 0; i < row_width; i++) + { + *dp-- = palette[*sp].blue; + *dp-- = palette[*sp].green; + *dp-- = palette[*sp].red; + sp--; + } + + row_info->bit_depth = 8; + row_info->pixel_depth = 24; + row_info->rowbytes = row_width * 3; + row_info->color_type = 2; + row_info->channels = 3; + } + break; + } + } + } +} + +/* If the bit depth < 8, it is expanded to 8. Also, if the already + * expanded transparency value is supplied, an alpha channel is built. + */ +void /* PRIVATE */ +png_do_expand(png_row_infop row_info, png_bytep row, + png_color_16p trans_value) +{ + int shift, value; + png_bytep sp, dp; + png_uint_32 i; + png_uint_32 row_width=row_info->width; + + png_debug(1, "in png_do_expand"); + + { + if (row_info->color_type == PNG_COLOR_TYPE_GRAY) + { + png_uint_16 gray = (png_uint_16)(trans_value ? trans_value->gray : 0); + + if (row_info->bit_depth < 8) + { + switch (row_info->bit_depth) + { + case 1: + { + gray = (png_uint_16)((gray&0x01)*0xff); + sp = row + (png_size_t)((row_width - 1) >> 3); + dp = row + (png_size_t)row_width - 1; + shift = 7 - (int)((row_width + 7) & 0x07); + for (i = 0; i < row_width; i++) + { + if ((*sp >> shift) & 0x01) + *dp = 0xff; + else + *dp = 0; + if (shift == 7) + { + shift = 0; + sp--; + } + else + shift++; + + dp--; + } + break; + } + + case 2: + { + gray = (png_uint_16)((gray&0x03)*0x55); + sp = row + (png_size_t)((row_width - 1) >> 2); + dp = row + (png_size_t)row_width - 1; + shift = (int)((3 - ((row_width + 3) & 0x03)) << 1); + for (i = 0; i < row_width; i++) + { + value = (*sp >> shift) & 0x03; + *dp = (png_byte)(value | (value << 2) | (value << 4) | + (value << 6)); + if (shift == 6) + { + shift = 0; + sp--; + } + else + shift += 2; + + dp--; + } + break; + } + + case 4: + { + gray = (png_uint_16)((gray&0x0f)*0x11); + sp = row + (png_size_t)((row_width - 1) >> 1); + dp = row + (png_size_t)row_width - 1; + shift = (int)((1 - ((row_width + 1) & 0x01)) << 2); + for (i = 0; i < row_width; i++) + { + value = (*sp >> shift) & 0x0f; + *dp = (png_byte)(value | (value << 4)); + if (shift == 4) + { + shift = 0; + sp--; + } + else + shift = 4; + + dp--; + } + break; + } + } + + row_info->bit_depth = 8; + row_info->pixel_depth = 8; + row_info->rowbytes = row_width; + } + + if (trans_value != NULL) + { + if (row_info->bit_depth == 8) + { + gray = gray & 0xff; + sp = row + (png_size_t)row_width - 1; + dp = row + (png_size_t)(row_width << 1) - 1; + for (i = 0; i < row_width; i++) + { + if (*sp == gray) + *dp-- = 0; + else + *dp-- = 0xff; + *dp-- = *sp--; + } + } + + else if (row_info->bit_depth == 16) + { + png_byte gray_high = (gray >> 8) & 0xff; + png_byte gray_low = gray & 0xff; + sp = row + row_info->rowbytes - 1; + dp = row + (row_info->rowbytes << 1) - 1; + for (i = 0; i < row_width; i++) + { + if (*(sp - 1) == gray_high && *(sp) == gray_low) + { + *dp-- = 0; + *dp-- = 0; + } + else + { + *dp-- = 0xff; + *dp-- = 0xff; + } + *dp-- = *sp--; + *dp-- = *sp--; + } + } + + row_info->color_type = PNG_COLOR_TYPE_GRAY_ALPHA; + row_info->channels = 2; + row_info->pixel_depth = (png_byte)(row_info->bit_depth << 1); + row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth, + row_width); + } + } + else if (row_info->color_type == PNG_COLOR_TYPE_RGB && trans_value) + { + if (row_info->bit_depth == 8) + { + png_byte red = trans_value->red & 0xff; + png_byte green = trans_value->green & 0xff; + png_byte blue = trans_value->blue & 0xff; + sp = row + (png_size_t)row_info->rowbytes - 1; + dp = row + (png_size_t)(row_width << 2) - 1; + for (i = 0; i < row_width; i++) + { + if (*(sp - 2) == red && *(sp - 1) == green && *(sp) == blue) + *dp-- = 0; + else + *dp-- = 0xff; + *dp-- = *sp--; + *dp-- = *sp--; + *dp-- = *sp--; + } + } + else if (row_info->bit_depth == 16) + { + png_byte red_high = (trans_value->red >> 8) & 0xff; + png_byte green_high = (trans_value->green >> 8) & 0xff; + png_byte blue_high = (trans_value->blue >> 8) & 0xff; + png_byte red_low = trans_value->red & 0xff; + png_byte green_low = trans_value->green & 0xff; + png_byte blue_low = trans_value->blue & 0xff; + sp = row + row_info->rowbytes - 1; + dp = row + (png_size_t)(row_width << 3) - 1; + for (i = 0; i < row_width; i++) + { + if (*(sp - 5) == red_high && + *(sp - 4) == red_low && + *(sp - 3) == green_high && + *(sp - 2) == green_low && + *(sp - 1) == blue_high && + *(sp ) == blue_low) + { + *dp-- = 0; + *dp-- = 0; + } + else + { + *dp-- = 0xff; + *dp-- = 0xff; + } + *dp-- = *sp--; + *dp-- = *sp--; + *dp-- = *sp--; + *dp-- = *sp--; + *dp-- = *sp--; + *dp-- = *sp--; + } + } + row_info->color_type = PNG_COLOR_TYPE_RGB_ALPHA; + row_info->channels = 4; + row_info->pixel_depth = (png_byte)(row_info->bit_depth << 2); + row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth, row_width); + } + } +} +#endif + +#ifdef PNG_READ_QUANTIZE_SUPPORTED +void /* PRIVATE */ +png_do_quantize(png_row_infop row_info, png_bytep row, + png_bytep palette_lookup, png_bytep quantize_lookup) +{ + png_bytep sp, dp; + png_uint_32 i; + png_uint_32 row_width=row_info->width; + + png_debug(1, "in png_do_quantize"); + + { + if (row_info->color_type == PNG_COLOR_TYPE_RGB && + palette_lookup && row_info->bit_depth == 8) + { + int r, g, b, p; + sp = row; + dp = row; + for (i = 0; i < row_width; i++) + { + r = *sp++; + g = *sp++; + b = *sp++; + + /* This looks real messy, but the compiler will reduce + * it down to a reasonable formula. For example, with + * 5 bits per color, we get: + * p = (((r >> 3) & 0x1f) << 10) | + * (((g >> 3) & 0x1f) << 5) | + * ((b >> 3) & 0x1f); + */ + p = (((r >> (8 - PNG_QUANTIZE_RED_BITS)) & + ((1 << PNG_QUANTIZE_RED_BITS) - 1)) << + (PNG_QUANTIZE_GREEN_BITS + PNG_QUANTIZE_BLUE_BITS)) | + (((g >> (8 - PNG_QUANTIZE_GREEN_BITS)) & + ((1 << PNG_QUANTIZE_GREEN_BITS) - 1)) << + (PNG_QUANTIZE_BLUE_BITS)) | + ((b >> (8 - PNG_QUANTIZE_BLUE_BITS)) & + ((1 << PNG_QUANTIZE_BLUE_BITS) - 1)); + + *dp++ = palette_lookup[p]; + } + row_info->color_type = PNG_COLOR_TYPE_PALETTE; + row_info->channels = 1; + row_info->pixel_depth = row_info->bit_depth; + row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth, row_width); + } + else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA && + palette_lookup != NULL && row_info->bit_depth == 8) + { + int r, g, b, p; + sp = row; + dp = row; + for (i = 0; i < row_width; i++) + { + r = *sp++; + g = *sp++; + b = *sp++; + sp++; + + p = (((r >> (8 - PNG_QUANTIZE_RED_BITS)) & + ((1 << PNG_QUANTIZE_RED_BITS) - 1)) << + (PNG_QUANTIZE_GREEN_BITS + PNG_QUANTIZE_BLUE_BITS)) | + (((g >> (8 - PNG_QUANTIZE_GREEN_BITS)) & + ((1 << PNG_QUANTIZE_GREEN_BITS) - 1)) << + (PNG_QUANTIZE_BLUE_BITS)) | + ((b >> (8 - PNG_QUANTIZE_BLUE_BITS)) & + ((1 << PNG_QUANTIZE_BLUE_BITS) - 1)); + + *dp++ = palette_lookup[p]; + } + row_info->color_type = PNG_COLOR_TYPE_PALETTE; + row_info->channels = 1; + row_info->pixel_depth = row_info->bit_depth; + row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth, row_width); + } + else if (row_info->color_type == PNG_COLOR_TYPE_PALETTE && + quantize_lookup && row_info->bit_depth == 8) + { + sp = row; + for (i = 0; i < row_width; i++, sp++) + { + *sp = quantize_lookup[*sp]; + } + } + } +} +#endif + +#ifdef PNG_FLOATING_POINT_SUPPORTED +#ifdef PNG_READ_GAMMA_SUPPORTED +static PNG_CONST int png_gamma_shift[] = + {0x10, 0x21, 0x42, 0x84, 0x110, 0x248, 0x550, 0xff0, 0x00}; + +/* We build the 8- or 16-bit gamma tables here. Note that for 16-bit + * tables, we don't make a full table if we are reducing to 8-bit in + * the future. Note also how the gamma_16 tables are segmented so that + * we don't need to allocate > 64K chunks for a full 16-bit table. + * + * See the PNG extensions document for an integer algorithm for creating + * the gamma tables. Maybe we will implement that here someday. + * + * We should only reach this point if + * + * the file_gamma is known (i.e., the gAMA or sRGB chunk is present, + * or the application has provided a file_gamma) + * + * AND + * { + * the screen_gamma is known + * + * OR + * + * RGB_to_gray transformation is being performed + * } + * + * AND + * { + * the screen_gamma is different from the reciprocal of the + * file_gamma by more than the specified threshold + * + * OR + * + * a background color has been specified and the file_gamma + * and screen_gamma are not 1.0, within the specified threshold. + * } + */ + +void /* PRIVATE */ +png_build_gamma_table(png_structp png_ptr, png_byte bit_depth) +{ + png_debug(1, "in png_build_gamma_table"); + + if (bit_depth <= 8) + { + int i; + double g; + + if (png_ptr->screen_gamma > .000001) + g = 1.0 / (png_ptr->gamma * png_ptr->screen_gamma); + + else + g = 1.0; + + png_ptr->gamma_table = (png_bytep)png_malloc(png_ptr, + (png_uint_32)256); + + for (i = 0; i < 256; i++) + { + png_ptr->gamma_table[i] = (png_byte)(pow((double)i / 255.0, + g) * 255.0 + .5); + } + +#if defined(PNG_READ_BACKGROUND_SUPPORTED) || \ + defined(PNG_READ_RGB_TO_GRAY_SUPPORTED) + if (png_ptr->transformations & ((PNG_BACKGROUND) | PNG_RGB_TO_GRAY)) + { + + g = 1.0 / (png_ptr->gamma); + + png_ptr->gamma_to_1 = (png_bytep)png_malloc(png_ptr, + (png_uint_32)256); + + for (i = 0; i < 256; i++) + { + png_ptr->gamma_to_1[i] = (png_byte)(pow((double)i / 255.0, + g) * 255.0 + .5); + } + + + png_ptr->gamma_from_1 = (png_bytep)png_malloc(png_ptr, + (png_uint_32)256); + + if (png_ptr->screen_gamma > 0.000001) + g = 1.0 / png_ptr->screen_gamma; + + else + g = png_ptr->gamma; /* Probably doing rgb_to_gray */ + + for (i = 0; i < 256; i++) + { + png_ptr->gamma_from_1[i] = (png_byte)(pow((double)i / 255.0, + g) * 255.0 + .5); + + } + } +#endif /* PNG_READ_BACKGROUND_SUPPORTED || PNG_RGB_TO_GRAY_SUPPORTED */ + } + else + { + double g; + int i, j, shift, num; + int sig_bit; + png_uint_32 ig; + + if (png_ptr->color_type & PNG_COLOR_MASK_COLOR) + { + sig_bit = (int)png_ptr->sig_bit.red; + + if ((int)png_ptr->sig_bit.green > sig_bit) + sig_bit = png_ptr->sig_bit.green; + + if ((int)png_ptr->sig_bit.blue > sig_bit) + sig_bit = png_ptr->sig_bit.blue; + } + else + { + sig_bit = (int)png_ptr->sig_bit.gray; + } + + if (sig_bit > 0) + shift = 16 - sig_bit; + + else + shift = 0; + + if (png_ptr->transformations & PNG_16_TO_8) + { + if (shift < (16 - PNG_MAX_GAMMA_8)) + shift = (16 - PNG_MAX_GAMMA_8); + } + + if (shift > 8) + shift = 8; + + if (shift < 0) + shift = 0; + + png_ptr->gamma_shift = (png_byte)shift; + + num = (1 << (8 - shift)); + + if (png_ptr->screen_gamma > .000001) + g = 1.0 / (png_ptr->gamma * png_ptr->screen_gamma); + else + g = 1.0; + + png_ptr->gamma_16_table = (png_uint_16pp)png_calloc(png_ptr, + (png_uint_32)(num * png_sizeof(png_uint_16p))); + + if (png_ptr->transformations & (PNG_16_TO_8 | PNG_BACKGROUND)) + { + double fin, fout; + png_uint_32 last, max; + + for (i = 0; i < num; i++) + { + png_ptr->gamma_16_table[i] = (png_uint_16p)png_malloc(png_ptr, + (png_uint_32)(256 * png_sizeof(png_uint_16))); + } + + g = 1.0 / g; + last = 0; + for (i = 0; i < 256; i++) + { + fout = ((double)i + 0.5) / 256.0; + fin = pow(fout, g); + max = (png_uint_32)(fin * (double)((png_uint_32)num << 8)); + while (last <= max) + { + png_ptr->gamma_16_table[(int)(last & (0xff >> shift))] + [(int)(last >> (8 - shift))] = (png_uint_16)( + (png_uint_16)i | ((png_uint_16)i << 8)); + last++; + } + } + while (last < ((png_uint_32)num << 8)) + { + png_ptr->gamma_16_table[(int)(last & (0xff >> shift))] + [(int)(last >> (8 - shift))] = (png_uint_16)65535L; + last++; + } + } + else + { + for (i = 0; i < num; i++) + { + png_ptr->gamma_16_table[i] = (png_uint_16p)png_malloc(png_ptr, + (png_uint_32)(256 * png_sizeof(png_uint_16))); + + ig = (((png_uint_32)i * (png_uint_32)png_gamma_shift[shift]) >> 4); + + for (j = 0; j < 256; j++) + { + png_ptr->gamma_16_table[i][j] = + (png_uint_16)(pow((double)(ig + ((png_uint_32)j << 8)) / + 65535.0, g) * 65535.0 + .5); + } + } + } + +#if defined(PNG_READ_BACKGROUND_SUPPORTED) || \ + defined(PNG_READ_RGB_TO_GRAY_SUPPORTED) + if (png_ptr->transformations & (PNG_BACKGROUND | PNG_RGB_TO_GRAY)) + { + + g = 1.0 / (png_ptr->gamma); + + png_ptr->gamma_16_to_1 = (png_uint_16pp)png_calloc(png_ptr, + (png_uint_32)(num * png_sizeof(png_uint_16p ))); + + for (i = 0; i < num; i++) + { + png_ptr->gamma_16_to_1[i] = (png_uint_16p)png_malloc(png_ptr, + (png_uint_32)(256 * png_sizeof(png_uint_16))); + + ig = (((png_uint_32)i * + (png_uint_32)png_gamma_shift[shift]) >> 4); + for (j = 0; j < 256; j++) + { + png_ptr->gamma_16_to_1[i][j] = + (png_uint_16)(pow((double)(ig + ((png_uint_32)j << 8)) / + 65535.0, g) * 65535.0 + .5); + } + } + + if (png_ptr->screen_gamma > 0.000001) + g = 1.0 / png_ptr->screen_gamma; + + else + g = png_ptr->gamma; /* Probably doing rgb_to_gray */ + + png_ptr->gamma_16_from_1 = (png_uint_16pp)png_calloc(png_ptr, + (png_uint_32)(num * png_sizeof(png_uint_16p))); + + for (i = 0; i < num; i++) + { + png_ptr->gamma_16_from_1[i] = (png_uint_16p)png_malloc(png_ptr, + (png_uint_32)(256 * png_sizeof(png_uint_16))); + + ig = (((png_uint_32)i * + (png_uint_32)png_gamma_shift[shift]) >> 4); + + for (j = 0; j < 256; j++) + { + png_ptr->gamma_16_from_1[i][j] = + (png_uint_16)(pow((double)(ig + ((png_uint_32)j << 8)) / + 65535.0, g) * 65535.0 + .5); + } + } + } +#endif /* PNG_READ_BACKGROUND_SUPPORTED || PNG_RGB_TO_GRAY_SUPPORTED */ + } +} +#endif +/* To do: install integer version of png_build_gamma_table here */ +#endif + +#ifdef PNG_MNG_FEATURES_SUPPORTED +/* Undoes intrapixel differencing */ +void /* PRIVATE */ +png_do_read_intrapixel(png_row_infop row_info, png_bytep row) +{ + png_debug(1, "in png_do_read_intrapixel"); + + if ( + (row_info->color_type & PNG_COLOR_MASK_COLOR)) + { + int bytes_per_pixel; + png_uint_32 row_width = row_info->width; + if (row_info->bit_depth == 8) + { + png_bytep rp; + png_uint_32 i; + + if (row_info->color_type == PNG_COLOR_TYPE_RGB) + bytes_per_pixel = 3; + + else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) + bytes_per_pixel = 4; + + else + return; + + for (i = 0, rp = row; i < row_width; i++, rp += bytes_per_pixel) + { + *(rp) = (png_byte)((256 + *rp + *(rp+1))&0xff); + *(rp+2) = (png_byte)((256 + *(rp+2) + *(rp+1))&0xff); + } + } + else if (row_info->bit_depth == 16) + { + png_bytep rp; + png_uint_32 i; + + if (row_info->color_type == PNG_COLOR_TYPE_RGB) + bytes_per_pixel = 6; + + else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) + bytes_per_pixel = 8; + + else + return; + + for (i = 0, rp = row; i < row_width; i++, rp += bytes_per_pixel) + { + png_uint_32 s0 = (*(rp ) << 8) | *(rp + 1); + png_uint_32 s1 = (*(rp + 2) << 8) | *(rp + 3); + png_uint_32 s2 = (*(rp + 4) << 8) | *(rp + 5); + png_uint_32 red = (png_uint_32)((s0 + s1 + 65536L) & 0xffffL); + png_uint_32 blue = (png_uint_32)((s2 + s1 + 65536L) & 0xffffL); + *(rp ) = (png_byte)((red >> 8) & 0xff); + *(rp+1) = (png_byte)(red & 0xff); + *(rp+4) = (png_byte)((blue >> 8) & 0xff); + *(rp+5) = (png_byte)(blue & 0xff); + } + } + } +} +#endif /* PNG_MNG_FEATURES_SUPPORTED */ +#endif /* PNG_READ_SUPPORTED */ diff --git a/libpng/pngrutil.c b/libpng/pngrutil.c new file mode 100644 index 0000000..11e412b --- /dev/null +++ b/libpng/pngrutil.c @@ -0,0 +1,3379 @@ + +/* pngrutil.c - utilities to read a PNG file + * + * Last changed in libpng 1.4.4 [August 26, 2010] + * Copyright (c) 1998-2010 Glenn Randers-Pehrson + * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) + * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) + * + * This code is released under the libpng license. + * For conditions of distribution and use, see the disclaimer + * and license in png.h + * + * This file contains routines that are only called from within + * libpng itself during the course of reading an image. + */ + +#define PNG_NO_PEDANTIC_WARNINGS +#include "png.h" +#ifdef PNG_READ_SUPPORTED +#include "pngpriv.h" + +# define png_strtod(p,a,b) strtod(a,b) +png_uint_32 PNGAPI +png_get_uint_31(png_structp png_ptr, png_bytep buf) +{ + png_uint_32 i = png_get_uint_32(buf); + if (i > PNG_UINT_31_MAX) + png_error(png_ptr, "PNG unsigned integer out of range"); + return (i); +} +#ifndef PNG_USE_READ_MACROS +/* Grab an unsigned 32-bit integer from a buffer in big-endian format. */ +png_uint_32 (PNGAPI +png_get_uint_32)(png_bytep buf) +{ + png_uint_32 i = + ((png_uint_32)(*(buf )) << 24) + + ((png_uint_32)(*(buf + 1)) << 16) + + ((png_uint_32)(*(buf + 2)) << 8) + + ((png_uint_32)(*(buf + 3)) ) ; + + return (i); +} + +/* Grab a signed 32-bit integer from a buffer in big-endian format. The + * data is stored in the PNG file in two's complement format and there + * is no guarantee that a 'png_int_32' is exactly 32 bits, therefore + * the following code does a two's complement to native conversion. + */ +png_int_32 (PNGAPI +png_get_int_32)(png_bytep buf) +{ + png_uint_32 u = png_get_uint_32(buf); + if ((u & 0x80000000) == 0) /* non-negative */ + return u; + + u = (u ^ 0xffffffff) + 1; /* 2's complement: -x = ~x+1 */ + return -(png_int_32)u; +} + +/* Grab an unsigned 16-bit integer from a buffer in big-endian format. */ +png_uint_16 (PNGAPI +png_get_uint_16)(png_bytep buf) +{ + png_uint_16 i = + ((png_uint_32)(*buf) << 8) + + ((png_uint_32)(*(buf + 1))); + + return (i); +} +#endif /* PNG_USE_READ_MACROS */ + +/* Read the chunk header (length + type name). + * Put the type name into png_ptr->chunk_name, and return the length. + */ +png_uint_32 /* PRIVATE */ +png_read_chunk_header(png_structp png_ptr) +{ + png_byte buf[8]; + png_uint_32 length; + +#ifdef PNG_IO_STATE_SUPPORTED + /* Inform the I/O callback that the chunk header is being read. + * PNG_IO_CHUNK_HDR requires a single I/O call. + */ + png_ptr->io_state = PNG_IO_READING | PNG_IO_CHUNK_HDR; +#endif + + /* Read the length and the chunk name */ + png_read_data(png_ptr, buf, 8); + length = png_get_uint_31(png_ptr, buf); + + /* Put the chunk name into png_ptr->chunk_name */ + png_memcpy(png_ptr->chunk_name, buf + 4, 4); + + png_debug2(0, "Reading %s chunk, length = %lu", + png_ptr->chunk_name, length); + + /* Reset the crc and run it over the chunk name */ + png_reset_crc(png_ptr); + png_calculate_crc(png_ptr, png_ptr->chunk_name, 4); + + /* Check to see if chunk name is valid */ + png_check_chunk_name(png_ptr, png_ptr->chunk_name); + +#ifdef PNG_IO_STATE_SUPPORTED + /* Inform the I/O callback that chunk data will (possibly) be read. + * PNG_IO_CHUNK_DATA does NOT require a specific number of I/O calls. + */ + png_ptr->io_state = PNG_IO_READING | PNG_IO_CHUNK_DATA; +#endif + + return length; +} + +/* Read data, and (optionally) run it through the CRC. */ +void /* PRIVATE */ +png_crc_read(png_structp png_ptr, png_bytep buf, png_size_t length) +{ + if (png_ptr == NULL) + return; + png_read_data(png_ptr, buf, length); + png_calculate_crc(png_ptr, buf, length); +} + +/* Optionally skip data and then check the CRC. Depending on whether we + * are reading a ancillary or critical chunk, and how the program has set + * things up, we may calculate the CRC on the data and print a message. + * Returns '1' if there was a CRC error, '0' otherwise. + */ +int /* PRIVATE */ +png_crc_finish(png_structp png_ptr, png_uint_32 skip) +{ + png_size_t i; + png_size_t istop = png_ptr->zbuf_size; + + for (i = (png_size_t)skip; i > istop; i -= istop) + { + png_crc_read(png_ptr, png_ptr->zbuf, png_ptr->zbuf_size); + } + if (i) + { + png_crc_read(png_ptr, png_ptr->zbuf, i); + } + + if (png_crc_error(png_ptr)) + { + if (((png_ptr->chunk_name[0] & 0x20) && /* Ancillary */ + !(png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_NOWARN)) || + (!(png_ptr->chunk_name[0] & 0x20) && /* Critical */ + (png_ptr->flags & PNG_FLAG_CRC_CRITICAL_USE))) + { + png_chunk_warning(png_ptr, "CRC error"); + } + else + { + png_chunk_benign_error(png_ptr, "CRC error"); + return (0); + } + return (1); + } + + return (0); +} + +/* Compare the CRC stored in the PNG file with that calculated by libpng from + * the data it has read thus far. + */ +int /* PRIVATE */ +png_crc_error(png_structp png_ptr) +{ + png_byte crc_bytes[4]; + png_uint_32 crc; + int need_crc = 1; + + if (png_ptr->chunk_name[0] & 0x20) /* ancillary */ + { + if ((png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_MASK) == + (PNG_FLAG_CRC_ANCILLARY_USE | PNG_FLAG_CRC_ANCILLARY_NOWARN)) + need_crc = 0; + } + else /* critical */ + { + if (png_ptr->flags & PNG_FLAG_CRC_CRITICAL_IGNORE) + need_crc = 0; + } + +#ifdef PNG_IO_STATE_SUPPORTED + /* Inform the I/O callback that the chunk CRC is being read */ + /* PNG_IO_CHUNK_CRC requires the I/O to be done at once */ + png_ptr->io_state = PNG_IO_READING | PNG_IO_CHUNK_CRC; +#endif + + png_read_data(png_ptr, crc_bytes, 4); + + if (need_crc) + { + crc = png_get_uint_32(crc_bytes); + return ((int)(crc != png_ptr->crc)); + } + else + return (0); +} + +#if defined(PNG_READ_zTXt_SUPPORTED) || defined(PNG_READ_iTXt_SUPPORTED) || \ + defined(PNG_READ_iCCP_SUPPORTED) +static png_size_t +png_inflate(png_structp png_ptr, const png_byte *data, png_size_t size, + png_bytep output, png_size_t output_size) +{ + png_size_t count = 0; + + png_ptr->zstream.next_in = (png_bytep)data; /* const_cast: VALID */ + png_ptr->zstream.avail_in = size; + + while (1) + { + int ret, avail; + + /* Reset the output buffer each time round - we empty it + * after every inflate call. + */ + png_ptr->zstream.next_out = png_ptr->zbuf; + png_ptr->zstream.avail_out = png_ptr->zbuf_size; + + ret = inflate(&png_ptr->zstream, Z_NO_FLUSH); + avail = png_ptr->zbuf_size - png_ptr->zstream.avail_out; + + /* First copy/count any new output - but only if we didn't + * get an error code. + */ + if ((ret == Z_OK || ret == Z_STREAM_END) && avail > 0) + { + if (output != 0 && output_size > count) + { + int copy = output_size - count; + if (avail < copy) copy = avail; + png_memcpy(output + count, png_ptr->zbuf, copy); + } + count += avail; + } + + if (ret == Z_OK) + continue; + + /* Termination conditions - always reset the zstream, it + * must be left in inflateInit state. + */ + png_ptr->zstream.avail_in = 0; + inflateReset(&png_ptr->zstream); + + if (ret == Z_STREAM_END) + return count; /* NOTE: may be zero. */ + + /* Now handle the error codes - the API always returns 0 + * and the error message is dumped into the uncompressed + * buffer if available. + */ + { + PNG_CONST char *msg; + if (png_ptr->zstream.msg != 0) + msg = png_ptr->zstream.msg; + else + { +#ifdef PNG_STDIO_SUPPORTED + char umsg[52]; + + switch (ret) + { + case Z_BUF_ERROR: + msg = "Buffer error in compressed datastream in %s chunk"; + break; + case Z_DATA_ERROR: + msg = "Data error in compressed datastream in %s chunk"; + break; + default: + msg = "Incomplete compressed datastream in %s chunk"; + break; + } + + png_snprintf(umsg, sizeof umsg, msg, png_ptr->chunk_name); + msg = umsg; +#else + msg = "Damaged compressed datastream in chunk other than IDAT"; +#endif + } + + png_warning(png_ptr, msg); + } + + /* 0 means an error - notice that this code simple ignores + * zero length compressed chunks as a result. + */ + return 0; + } +} + +/* + * Decompress trailing data in a chunk. The assumption is that chunkdata + * points at an allocated area holding the contents of a chunk with a + * trailing compressed part. What we get back is an allocated area + * holding the original prefix part and an uncompressed version of the + * trailing part (the malloc area passed in is freed). + */ +void /* PRIVATE */ +png_decompress_chunk(png_structp png_ptr, int comp_type, + png_size_t chunklength, + png_size_t prefix_size, png_size_t *newlength) +{ + /* The caller should guarantee this */ + if (prefix_size > chunklength) + { + /* The recovery is to delete the chunk. */ + png_warning(png_ptr, "invalid chunklength"); + prefix_size = 0; /* To delete everything */ + } + + else if (comp_type == PNG_COMPRESSION_TYPE_BASE) + { + png_size_t expanded_size = png_inflate(png_ptr, + (png_bytep)(png_ptr->chunkdata + prefix_size), + chunklength - prefix_size, + 0/*output*/, 0/*output size*/); + + /* Now check the limits on this chunk - if the limit fails the + * compressed data will be removed, the prefix will remain. + */ +#ifdef PNG_SET_CHUNK_MALLOC_LIMIT_SUPPORTED + if (png_ptr->user_chunk_malloc_max && + (prefix_size + expanded_size >= png_ptr->user_chunk_malloc_max - 1)) +#else +# ifdef PNG_USER_CHUNK_MALLOC_MAX + if ((PNG_USER_CHUNK_MALLOC_MAX > 0) && + prefix_size + expanded_size >= PNG_USER_CHUNK_MALLOC_MAX - 1) +# endif +#endif + png_warning(png_ptr, "Exceeded size limit while expanding chunk"); + + /* If the size is zero either there was an error and a message + * has already been output (warning) or the size really is zero + * and we have nothing to do - the code will exit through the + * error case below. + */ +#if defined(PNG_SET_CHUNK_MALLOC_LIMIT_SUPPORTED) || \ + defined(PNG_USER_CHUNK_MALLOC_MAX) + else +#endif + if (expanded_size > 0) + { + /* Success (maybe) - really uncompress the chunk. */ + png_size_t new_size = 0; + png_charp text = png_malloc_warn(png_ptr, + prefix_size + expanded_size + 1); + + if (text != NULL) + { + png_memcpy(text, png_ptr->chunkdata, prefix_size); + new_size = png_inflate(png_ptr, + (png_bytep)(png_ptr->chunkdata + prefix_size), + chunklength - prefix_size, + (png_bytep)(text + prefix_size), expanded_size); + text[prefix_size + expanded_size] = 0; /* just in case */ + + if (new_size == expanded_size) + { + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = text; + *newlength = prefix_size + expanded_size; + return; /* The success return! */ + } + + png_warning(png_ptr, "png_inflate logic error"); + png_free(png_ptr, text); + } + else + png_warning(png_ptr, "Not enough memory to decompress chunk"); + } + } + + else /* if (comp_type != PNG_COMPRESSION_TYPE_BASE) */ + { +#ifdef PNG_STDIO_SUPPORTED + char umsg[50]; + + png_snprintf(umsg, sizeof umsg, "Unknown zTXt compression type %d", + comp_type); + png_warning(png_ptr, umsg); +#else + png_warning(png_ptr, "Unknown zTXt compression type"); +#endif + + /* The recovery is to simply drop the data. */ + } + + /* Generic error return - leave the prefix, delete the compressed + * data, reallocate the chunkdata to remove the potentially large + * amount of compressed data. + */ + { + png_charp text = png_malloc_warn(png_ptr, prefix_size + 1); + if (text != NULL) + { + if (prefix_size > 0) + png_memcpy(text, png_ptr->chunkdata, prefix_size); + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = text; + + /* This is an extra zero in the 'uncompressed' part. */ + *(png_ptr->chunkdata + prefix_size) = 0x00; + } + /* Ignore a malloc error here - it is safe. */ + } + + *newlength = prefix_size; +} +#endif + +/* Read and check the IDHR chunk */ +void /* PRIVATE */ +png_handle_IHDR(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) +{ + png_byte buf[13]; + png_uint_32 width, height; + int bit_depth, color_type, compression_type, filter_type; + int interlace_type; + + png_debug(1, "in png_handle_IHDR"); + + if (png_ptr->mode & PNG_HAVE_IHDR) + png_error(png_ptr, "Out of place IHDR"); + + /* Check the length */ + if (length != 13) + png_error(png_ptr, "Invalid IHDR chunk"); + + png_ptr->mode |= PNG_HAVE_IHDR; + + png_crc_read(png_ptr, buf, 13); + png_crc_finish(png_ptr, 0); + + width = png_get_uint_31(png_ptr, buf); + height = png_get_uint_31(png_ptr, buf + 4); + bit_depth = buf[8]; + color_type = buf[9]; + compression_type = buf[10]; + filter_type = buf[11]; + interlace_type = buf[12]; + + /* Set internal variables */ + png_ptr->width = width; + png_ptr->height = height; + png_ptr->bit_depth = (png_byte)bit_depth; + png_ptr->interlaced = (png_byte)interlace_type; + png_ptr->color_type = (png_byte)color_type; +#ifdef PNG_MNG_FEATURES_SUPPORTED + png_ptr->filter_type = (png_byte)filter_type; +#endif + png_ptr->compression_type = (png_byte)compression_type; + + /* Find number of channels */ + switch (png_ptr->color_type) + { + case PNG_COLOR_TYPE_GRAY: + case PNG_COLOR_TYPE_PALETTE: + png_ptr->channels = 1; + break; + + case PNG_COLOR_TYPE_RGB: + png_ptr->channels = 3; + break; + + case PNG_COLOR_TYPE_GRAY_ALPHA: + png_ptr->channels = 2; + break; + + case PNG_COLOR_TYPE_RGB_ALPHA: + png_ptr->channels = 4; + break; + } + + /* Set up other useful info */ + png_ptr->pixel_depth = (png_byte)(png_ptr->bit_depth * + png_ptr->channels); + png_ptr->rowbytes = PNG_ROWBYTES(png_ptr->pixel_depth, png_ptr->width); + png_debug1(3, "bit_depth = %d", png_ptr->bit_depth); + png_debug1(3, "channels = %d", png_ptr->channels); + png_debug1(3, "rowbytes = %lu", png_ptr->rowbytes); + png_set_IHDR(png_ptr, info_ptr, width, height, bit_depth, + color_type, interlace_type, compression_type, filter_type); +} + +/* Read and check the palette */ +void /* PRIVATE */ +png_handle_PLTE(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) +{ + png_color palette[PNG_MAX_PALETTE_LENGTH]; + int num, i; +#ifdef PNG_POINTER_INDEXING_SUPPORTED + png_colorp pal_ptr; +#endif + + png_debug(1, "in png_handle_PLTE"); + + if (!(png_ptr->mode & PNG_HAVE_IHDR)) + png_error(png_ptr, "Missing IHDR before PLTE"); + + else if (png_ptr->mode & PNG_HAVE_IDAT) + { + png_warning(png_ptr, "Invalid PLTE after IDAT"); + png_crc_finish(png_ptr, length); + return; + } + + else if (png_ptr->mode & PNG_HAVE_PLTE) + png_error(png_ptr, "Duplicate PLTE chunk"); + + png_ptr->mode |= PNG_HAVE_PLTE; + + if (!(png_ptr->color_type&PNG_COLOR_MASK_COLOR)) + { + png_warning(png_ptr, + "Ignoring PLTE chunk in grayscale PNG"); + png_crc_finish(png_ptr, length); + return; + } +#ifndef PNG_READ_OPT_PLTE_SUPPORTED + if (png_ptr->color_type != PNG_COLOR_TYPE_PALETTE) + { + png_crc_finish(png_ptr, length); + return; + } +#endif + + if (length > 3*PNG_MAX_PALETTE_LENGTH || length % 3) + { + if (png_ptr->color_type != PNG_COLOR_TYPE_PALETTE) + { + png_warning(png_ptr, "Invalid palette chunk"); + png_crc_finish(png_ptr, length); + return; + } + + else + { + png_error(png_ptr, "Invalid palette chunk"); + } + } + + num = (int)length / 3; + +#ifdef PNG_POINTER_INDEXING_SUPPORTED + for (i = 0, pal_ptr = palette; i < num; i++, pal_ptr++) + { + png_byte buf[3]; + + png_crc_read(png_ptr, buf, 3); + pal_ptr->red = buf[0]; + pal_ptr->green = buf[1]; + pal_ptr->blue = buf[2]; + } +#else + for (i = 0; i < num; i++) + { + png_byte buf[3]; + + png_crc_read(png_ptr, buf, 3); + /* Don't depend upon png_color being any order */ + palette[i].red = buf[0]; + palette[i].green = buf[1]; + palette[i].blue = buf[2]; + } +#endif + + /* If we actually NEED the PLTE chunk (ie for a paletted image), we do + * whatever the normal CRC configuration tells us. However, if we + * have an RGB image, the PLTE can be considered ancillary, so + * we will act as though it is. + */ +#ifndef PNG_READ_OPT_PLTE_SUPPORTED + if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) +#endif + { + png_crc_finish(png_ptr, 0); + } +#ifndef PNG_READ_OPT_PLTE_SUPPORTED + else if (png_crc_error(png_ptr)) /* Only if we have a CRC error */ + { + /* If we don't want to use the data from an ancillary chunk, + we have two options: an error abort, or a warning and we + ignore the data in this chunk (which should be OK, since + it's considered ancillary for a RGB or RGBA image). */ + if (!(png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_USE)) + { + if (png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_NOWARN) + { + png_chunk_benign_error(png_ptr, "CRC error"); + } + else + { + png_chunk_warning(png_ptr, "CRC error"); + return; + } + } + /* Otherwise, we (optionally) emit a warning and use the chunk. */ + else if (!(png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_NOWARN)) + { + png_chunk_warning(png_ptr, "CRC error"); + } + } +#endif + + png_set_PLTE(png_ptr, info_ptr, palette, num); + +#ifdef PNG_READ_tRNS_SUPPORTED + if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) + { + if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_tRNS)) + { + if (png_ptr->num_trans > (png_uint_16)num) + { + png_warning(png_ptr, "Truncating incorrect tRNS chunk length"); + png_ptr->num_trans = (png_uint_16)num; + } + if (info_ptr->num_trans > (png_uint_16)num) + { + png_warning(png_ptr, "Truncating incorrect info tRNS chunk length"); + info_ptr->num_trans = (png_uint_16)num; + } + } + } +#endif + +} + +void /* PRIVATE */ +png_handle_IEND(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) +{ + png_debug(1, "in png_handle_IEND"); + + if (!(png_ptr->mode & PNG_HAVE_IHDR) || !(png_ptr->mode & PNG_HAVE_IDAT)) + { + png_error(png_ptr, "No image in file"); + } + + png_ptr->mode |= (PNG_AFTER_IDAT | PNG_HAVE_IEND); + + if (length != 0) + { + png_warning(png_ptr, "Incorrect IEND chunk length"); + } + png_crc_finish(png_ptr, length); + + info_ptr = info_ptr; /* Quiet compiler warnings about unused info_ptr */ +} + +#ifdef PNG_READ_gAMA_SUPPORTED +void /* PRIVATE */ +png_handle_gAMA(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) +{ + png_fixed_point igamma; +#ifdef PNG_FLOATING_POINT_SUPPORTED + float file_gamma; +#endif + png_byte buf[4]; + + png_debug(1, "in png_handle_gAMA"); + + if (!(png_ptr->mode & PNG_HAVE_IHDR)) + png_error(png_ptr, "Missing IHDR before gAMA"); + else if (png_ptr->mode & PNG_HAVE_IDAT) + { + png_warning(png_ptr, "Invalid gAMA after IDAT"); + png_crc_finish(png_ptr, length); + return; + } + else if (png_ptr->mode & PNG_HAVE_PLTE) + /* Should be an error, but we can cope with it */ + png_warning(png_ptr, "Out of place gAMA chunk"); + + if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_gAMA) +#ifdef PNG_READ_sRGB_SUPPORTED + && !(info_ptr->valid & PNG_INFO_sRGB) +#endif + ) + { + png_warning(png_ptr, "Duplicate gAMA chunk"); + png_crc_finish(png_ptr, length); + return; + } + + if (length != 4) + { + png_warning(png_ptr, "Incorrect gAMA chunk length"); + png_crc_finish(png_ptr, length); + return; + } + + png_crc_read(png_ptr, buf, 4); + if (png_crc_finish(png_ptr, 0)) + return; + + igamma = (png_fixed_point)png_get_uint_32(buf); + /* Check for zero gamma */ + if (igamma == 0) + { + png_warning(png_ptr, + "Ignoring gAMA chunk with gamma=0"); + return; + } + +#ifdef PNG_READ_sRGB_SUPPORTED + if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_sRGB)) + if (PNG_OUT_OF_RANGE(igamma, 45500L, 500)) + { + png_warning(png_ptr, + "Ignoring incorrect gAMA value when sRGB is also present"); +#ifdef PNG_CONSOLE_IO_SUPPORTED + fprintf(stderr, "gamma = (%d/100000)", (int)igamma); +#endif + return; + } +#endif /* PNG_READ_sRGB_SUPPORTED */ + +#ifdef PNG_FLOATING_POINT_SUPPORTED + file_gamma = (float)igamma / (float)100000.0; +# ifdef PNG_READ_GAMMA_SUPPORTED + png_ptr->gamma = file_gamma; +# endif + png_set_gAMA(png_ptr, info_ptr, file_gamma); +#endif +#ifdef PNG_FIXED_POINT_SUPPORTED + png_set_gAMA_fixed(png_ptr, info_ptr, igamma); +#endif +} +#endif + +#ifdef PNG_READ_sBIT_SUPPORTED +void /* PRIVATE */ +png_handle_sBIT(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) +{ + png_size_t truelen; + png_byte buf[4]; + + png_debug(1, "in png_handle_sBIT"); + + buf[0] = buf[1] = buf[2] = buf[3] = 0; + + if (!(png_ptr->mode & PNG_HAVE_IHDR)) + png_error(png_ptr, "Missing IHDR before sBIT"); + else if (png_ptr->mode & PNG_HAVE_IDAT) + { + png_warning(png_ptr, "Invalid sBIT after IDAT"); + png_crc_finish(png_ptr, length); + return; + } + else if (png_ptr->mode & PNG_HAVE_PLTE) + { + /* Should be an error, but we can cope with it */ + png_warning(png_ptr, "Out of place sBIT chunk"); + } + if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_sBIT)) + { + png_warning(png_ptr, "Duplicate sBIT chunk"); + png_crc_finish(png_ptr, length); + return; + } + + if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) + truelen = 3; + else + truelen = (png_size_t)png_ptr->channels; + + if (length != truelen || length > 4) + { + png_warning(png_ptr, "Incorrect sBIT chunk length"); + png_crc_finish(png_ptr, length); + return; + } + + png_crc_read(png_ptr, buf, truelen); + if (png_crc_finish(png_ptr, 0)) + return; + + if (png_ptr->color_type & PNG_COLOR_MASK_COLOR) + { + png_ptr->sig_bit.red = buf[0]; + png_ptr->sig_bit.green = buf[1]; + png_ptr->sig_bit.blue = buf[2]; + png_ptr->sig_bit.alpha = buf[3]; + } + else + { + png_ptr->sig_bit.gray = buf[0]; + png_ptr->sig_bit.red = buf[0]; + png_ptr->sig_bit.green = buf[0]; + png_ptr->sig_bit.blue = buf[0]; + png_ptr->sig_bit.alpha = buf[1]; + } + png_set_sBIT(png_ptr, info_ptr, &(png_ptr->sig_bit)); +} +#endif + +#ifdef PNG_READ_cHRM_SUPPORTED +void /* PRIVATE */ +png_handle_cHRM(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) +{ + png_byte buf[32]; +#ifdef PNG_FLOATING_POINT_SUPPORTED + float white_x, white_y, red_x, red_y, green_x, green_y, blue_x, blue_y; +#endif + png_fixed_point int_x_white, int_y_white, int_x_red, int_y_red, int_x_green, + int_y_green, int_x_blue, int_y_blue; + + png_uint_32 uint_x, uint_y; + + png_debug(1, "in png_handle_cHRM"); + + if (!(png_ptr->mode & PNG_HAVE_IHDR)) + png_error(png_ptr, "Missing IHDR before cHRM"); + else if (png_ptr->mode & PNG_HAVE_IDAT) + { + png_warning(png_ptr, "Invalid cHRM after IDAT"); + png_crc_finish(png_ptr, length); + return; + } + else if (png_ptr->mode & PNG_HAVE_PLTE) + /* Should be an error, but we can cope with it */ + png_warning(png_ptr, "Missing PLTE before cHRM"); + + if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_cHRM) +#ifdef PNG_READ_sRGB_SUPPORTED + && !(info_ptr->valid & PNG_INFO_sRGB) +#endif + ) + { + png_warning(png_ptr, "Duplicate cHRM chunk"); + png_crc_finish(png_ptr, length); + return; + } + + if (length != 32) + { + png_warning(png_ptr, "Incorrect cHRM chunk length"); + png_crc_finish(png_ptr, length); + return; + } + + png_crc_read(png_ptr, buf, 32); + if (png_crc_finish(png_ptr, 0)) + return; + + uint_x = png_get_uint_32(buf); + uint_y = png_get_uint_32(buf + 4); + int_x_white = (png_fixed_point)uint_x; + int_y_white = (png_fixed_point)uint_y; + + uint_x = png_get_uint_32(buf + 8); + uint_y = png_get_uint_32(buf + 12); + int_x_red = (png_fixed_point)uint_x; + int_y_red = (png_fixed_point)uint_y; + + uint_x = png_get_uint_32(buf + 16); + uint_y = png_get_uint_32(buf + 20); + int_x_green = (png_fixed_point)uint_x; + int_y_green = (png_fixed_point)uint_y; + + uint_x = png_get_uint_32(buf + 24); + uint_y = png_get_uint_32(buf + 28); + int_x_blue = (png_fixed_point)uint_x; + int_y_blue = (png_fixed_point)uint_y; + +#ifdef PNG_FLOATING_POINT_SUPPORTED + white_x = (float)int_x_white / (float)100000.0; + white_y = (float)int_y_white / (float)100000.0; + red_x = (float)int_x_red / (float)100000.0; + red_y = (float)int_y_red / (float)100000.0; + green_x = (float)int_x_green / (float)100000.0; + green_y = (float)int_y_green / (float)100000.0; + blue_x = (float)int_x_blue / (float)100000.0; + blue_y = (float)int_y_blue / (float)100000.0; +#endif + +#ifdef PNG_READ_sRGB_SUPPORTED + if ((info_ptr != NULL) && (info_ptr->valid & PNG_INFO_sRGB)) + { + if (PNG_OUT_OF_RANGE(int_x_white, 31270, 1000) || + PNG_OUT_OF_RANGE(int_y_white, 32900, 1000) || + PNG_OUT_OF_RANGE(int_x_red, 64000L, 1000) || + PNG_OUT_OF_RANGE(int_y_red, 33000, 1000) || + PNG_OUT_OF_RANGE(int_x_green, 30000, 1000) || + PNG_OUT_OF_RANGE(int_y_green, 60000L, 1000) || + PNG_OUT_OF_RANGE(int_x_blue, 15000, 1000) || + PNG_OUT_OF_RANGE(int_y_blue, 6000, 1000)) + { + png_warning(png_ptr, + "Ignoring incorrect cHRM value when sRGB is also present"); +#ifdef PNG_CONSOLE_IO_SUPPORTED +#ifdef PNG_FLOATING_POINT_SUPPORTED + fprintf(stderr, "wx=%f, wy=%f, rx=%f, ry=%f\n", + white_x, white_y, red_x, red_y); + fprintf(stderr, "gx=%f, gy=%f, bx=%f, by=%f\n", + green_x, green_y, blue_x, blue_y); +#else + fprintf(stderr, "wx=%ld, wy=%ld, rx=%ld, ry=%ld\n", + (long)int_x_white, (long)int_y_white, + (long)int_x_red, (long)int_y_red); + fprintf(stderr, "gx=%ld, gy=%ld, bx=%ld, by=%ld\n", + (long)int_x_green, (long)int_y_green, + (long)int_x_blue, (long)int_y_blue); +#endif +#endif /* PNG_CONSOLE_IO_SUPPORTED */ + } + return; + } +#endif /* PNG_READ_sRGB_SUPPORTED */ + +#ifdef PNG_FLOATING_POINT_SUPPORTED + png_set_cHRM(png_ptr, info_ptr, + white_x, white_y, red_x, red_y, green_x, green_y, blue_x, blue_y); +#endif +#ifdef PNG_FIXED_POINT_SUPPORTED + png_set_cHRM_fixed(png_ptr, info_ptr, + int_x_white, int_y_white, int_x_red, int_y_red, int_x_green, + int_y_green, int_x_blue, int_y_blue); +#endif +} +#endif + +#ifdef PNG_READ_sRGB_SUPPORTED +void /* PRIVATE */ +png_handle_sRGB(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) +{ + int intent; + png_byte buf[1]; + + png_debug(1, "in png_handle_sRGB"); + + if (!(png_ptr->mode & PNG_HAVE_IHDR)) + png_error(png_ptr, "Missing IHDR before sRGB"); + else if (png_ptr->mode & PNG_HAVE_IDAT) + { + png_warning(png_ptr, "Invalid sRGB after IDAT"); + png_crc_finish(png_ptr, length); + return; + } + else if (png_ptr->mode & PNG_HAVE_PLTE) + /* Should be an error, but we can cope with it */ + png_warning(png_ptr, "Out of place sRGB chunk"); + + if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_sRGB)) + { + png_warning(png_ptr, "Duplicate sRGB chunk"); + png_crc_finish(png_ptr, length); + return; + } + + if (length != 1) + { + png_warning(png_ptr, "Incorrect sRGB chunk length"); + png_crc_finish(png_ptr, length); + return; + } + + png_crc_read(png_ptr, buf, 1); + if (png_crc_finish(png_ptr, 0)) + return; + + intent = buf[0]; + /* Check for bad intent */ + if (intent >= PNG_sRGB_INTENT_LAST) + { + png_warning(png_ptr, "Unknown sRGB intent"); + return; + } + +#if defined(PNG_READ_gAMA_SUPPORTED) && defined(PNG_READ_GAMMA_SUPPORTED) + if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_gAMA)) + { + png_fixed_point igamma; +#ifdef PNG_FIXED_POINT_SUPPORTED + igamma=info_ptr->int_gamma; +#else +# ifdef PNG_FLOATING_POINT_SUPPORTED + igamma=(png_fixed_point)(info_ptr->gamma * 100000.); +# endif +#endif + if (PNG_OUT_OF_RANGE(igamma, 45500L, 500)) + { + png_warning(png_ptr, + "Ignoring incorrect gAMA value when sRGB is also present"); +#ifdef PNG_CONSOLE_IO_SUPPORTED +# ifdef PNG_FIXED_POINT_SUPPORTED + fprintf(stderr, "incorrect gamma=(%d/100000)\n", + (int)png_ptr->int_gamma); +# else +# ifdef PNG_FLOATING_POINT_SUPPORTED + fprintf(stderr, "incorrect gamma=%f\n", png_ptr->gamma); +# endif +# endif +#endif + } + } +#endif /* PNG_READ_gAMA_SUPPORTED */ + +#ifdef PNG_READ_cHRM_SUPPORTED +#ifdef PNG_FIXED_POINT_SUPPORTED + if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_cHRM)) + if (PNG_OUT_OF_RANGE(info_ptr->int_x_white, 31270, 1000) || + PNG_OUT_OF_RANGE(info_ptr->int_y_white, 32900, 1000) || + PNG_OUT_OF_RANGE(info_ptr->int_x_red, 64000L, 1000) || + PNG_OUT_OF_RANGE(info_ptr->int_y_red, 33000, 1000) || + PNG_OUT_OF_RANGE(info_ptr->int_x_green, 30000, 1000) || + PNG_OUT_OF_RANGE(info_ptr->int_y_green, 60000L, 1000) || + PNG_OUT_OF_RANGE(info_ptr->int_x_blue, 15000, 1000) || + PNG_OUT_OF_RANGE(info_ptr->int_y_blue, 6000, 1000)) + { + png_warning(png_ptr, + "Ignoring incorrect cHRM value when sRGB is also present"); + } +#endif /* PNG_FIXED_POINT_SUPPORTED */ +#endif /* PNG_READ_cHRM_SUPPORTED */ + + png_set_sRGB_gAMA_and_cHRM(png_ptr, info_ptr, intent); +} +#endif /* PNG_READ_sRGB_SUPPORTED */ + +#ifdef PNG_READ_iCCP_SUPPORTED +void /* PRIVATE */ +png_handle_iCCP(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) +/* Note: this does not properly handle chunks that are > 64K under DOS */ +{ + png_byte compression_type; + png_bytep pC; + png_charp profile; + png_uint_32 skip = 0; + png_uint_32 profile_size, profile_length; + png_size_t slength, prefix_length, data_length; + + png_debug(1, "in png_handle_iCCP"); + + if (!(png_ptr->mode & PNG_HAVE_IHDR)) + png_error(png_ptr, "Missing IHDR before iCCP"); + else if (png_ptr->mode & PNG_HAVE_IDAT) + { + png_warning(png_ptr, "Invalid iCCP after IDAT"); + png_crc_finish(png_ptr, length); + return; + } + else if (png_ptr->mode & PNG_HAVE_PLTE) + /* Should be an error, but we can cope with it */ + png_warning(png_ptr, "Out of place iCCP chunk"); + + if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_iCCP)) + { + png_warning(png_ptr, "Duplicate iCCP chunk"); + png_crc_finish(png_ptr, length); + return; + } + +#ifdef PNG_MAX_MALLOC_64K + if (length > (png_uint_32)65535L) + { + png_warning(png_ptr, "iCCP chunk too large to fit in memory"); + skip = length - (png_uint_32)65535L; + length = (png_uint_32)65535L; + } +#endif + + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = (png_charp)png_malloc(png_ptr, length + 1); + slength = (png_size_t)length; + png_crc_read(png_ptr, (png_bytep)png_ptr->chunkdata, slength); + + if (png_crc_finish(png_ptr, skip)) + { + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = NULL; + return; + } + + png_ptr->chunkdata[slength] = 0x00; + + for (profile = png_ptr->chunkdata; *profile; profile++) + /* Empty loop to find end of name */ ; + + ++profile; + + /* There should be at least one zero (the compression type byte) + * following the separator, and we should be on it + */ + if ( profile >= png_ptr->chunkdata + slength - 1) + { + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = NULL; + png_warning(png_ptr, "Malformed iCCP chunk"); + return; + } + + /* Compression_type should always be zero */ + compression_type = *profile++; + if (compression_type) + { + png_warning(png_ptr, "Ignoring nonzero compression type in iCCP chunk"); + compression_type = 0x00; /* Reset it to zero (libpng-1.0.6 through 1.0.8 + wrote nonzero) */ + } + + prefix_length = profile - png_ptr->chunkdata; + png_decompress_chunk(png_ptr, compression_type, + slength, prefix_length, &data_length); + + profile_length = data_length - prefix_length; + + if ( prefix_length > data_length || profile_length < 4) + { + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = NULL; + png_warning(png_ptr, "Profile size field missing from iCCP chunk"); + return; + } + + /* Check the profile_size recorded in the first 32 bits of the ICC profile */ + pC = (png_bytep)(png_ptr->chunkdata + prefix_length); + profile_size = ((*(pC ))<<24) | + ((*(pC + 1))<<16) | + ((*(pC + 2))<< 8) | + ((*(pC + 3)) ); + + if (profile_size < profile_length) + profile_length = profile_size; + + if (profile_size > profile_length) + { +#ifdef PNG_STDIO_SUPPORTED + char umsg[50]; +#endif + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = NULL; + png_warning(png_ptr, "Ignoring truncated iCCP profile"); +#ifdef PNG_STDIO_SUPPORTED + + png_snprintf(umsg, 50, "declared profile size = %lu", + (unsigned long)profile_size); + png_warning(png_ptr, umsg); + png_snprintf(umsg, 50, "actual profile length = %lu", + (unsigned long)profile_length); + png_warning(png_ptr, umsg); +#endif + return; + } + + png_set_iCCP(png_ptr, info_ptr, png_ptr->chunkdata, + compression_type, png_ptr->chunkdata + prefix_length, profile_length); + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = NULL; +} +#endif /* PNG_READ_iCCP_SUPPORTED */ + +#ifdef PNG_READ_sPLT_SUPPORTED +void /* PRIVATE */ +png_handle_sPLT(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) +/* Note: this does not properly handle chunks that are > 64K under DOS */ +{ + png_bytep entry_start; + png_sPLT_t new_palette; +#ifdef PNG_POINTER_INDEXING_SUPPORTED + png_sPLT_entryp pp; +#endif + int data_length, entry_size, i; + png_uint_32 skip = 0; + png_size_t slength; + + png_debug(1, "in png_handle_sPLT"); + +#ifdef PNG_USER_LIMITS_SUPPORTED + + if (png_ptr->user_chunk_cache_max != 0) + { + if (png_ptr->user_chunk_cache_max == 1) + { + png_crc_finish(png_ptr, length); + return; + } + if (--png_ptr->user_chunk_cache_max == 1) + { + png_warning(png_ptr, "No space in chunk cache for sPLT"); + png_crc_finish(png_ptr, length); + return; + } + } +#endif + + if (!(png_ptr->mode & PNG_HAVE_IHDR)) + png_error(png_ptr, "Missing IHDR before sPLT"); + else if (png_ptr->mode & PNG_HAVE_IDAT) + { + png_warning(png_ptr, "Invalid sPLT after IDAT"); + png_crc_finish(png_ptr, length); + return; + } + +#ifdef PNG_MAX_MALLOC_64K + if (length > (png_uint_32)65535L) + { + png_warning(png_ptr, "sPLT chunk too large to fit in memory"); + skip = length - (png_uint_32)65535L; + length = (png_uint_32)65535L; + } +#endif + + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = (png_charp)png_malloc(png_ptr, length + 1); + slength = (png_size_t)length; + png_crc_read(png_ptr, (png_bytep)png_ptr->chunkdata, slength); + + if (png_crc_finish(png_ptr, skip)) + { + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = NULL; + return; + } + + png_ptr->chunkdata[slength] = 0x00; + + for (entry_start = (png_bytep)png_ptr->chunkdata; *entry_start; + entry_start++) + /* Empty loop to find end of name */ ; + ++entry_start; + + /* A sample depth should follow the separator, and we should be on it */ + if (entry_start > (png_bytep)png_ptr->chunkdata + slength - 2) + { + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = NULL; + png_warning(png_ptr, "malformed sPLT chunk"); + return; + } + + new_palette.depth = *entry_start++; + entry_size = (new_palette.depth == 8 ? 6 : 10); + data_length = (slength - (entry_start - (png_bytep)png_ptr->chunkdata)); + + /* Integrity-check the data length */ + if (data_length % entry_size) + { + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = NULL; + png_warning(png_ptr, "sPLT chunk has bad length"); + return; + } + + new_palette.nentries = (png_int_32) ( data_length / entry_size); + if ((png_uint_32) new_palette.nentries > + (png_uint_32) (PNG_SIZE_MAX / png_sizeof(png_sPLT_entry))) + { + png_warning(png_ptr, "sPLT chunk too long"); + return; + } + new_palette.entries = (png_sPLT_entryp)png_malloc_warn( + png_ptr, new_palette.nentries * png_sizeof(png_sPLT_entry)); + if (new_palette.entries == NULL) + { + png_warning(png_ptr, "sPLT chunk requires too much memory"); + return; + } + +#ifdef PNG_POINTER_INDEXING_SUPPORTED + for (i = 0; i < new_palette.nentries; i++) + { + pp = new_palette.entries + i; + + if (new_palette.depth == 8) + { + pp->red = *entry_start++; + pp->green = *entry_start++; + pp->blue = *entry_start++; + pp->alpha = *entry_start++; + } + else + { + pp->red = png_get_uint_16(entry_start); entry_start += 2; + pp->green = png_get_uint_16(entry_start); entry_start += 2; + pp->blue = png_get_uint_16(entry_start); entry_start += 2; + pp->alpha = png_get_uint_16(entry_start); entry_start += 2; + } + pp->frequency = png_get_uint_16(entry_start); entry_start += 2; + } +#else + pp = new_palette.entries; + for (i = 0; i < new_palette.nentries; i++) + { + + if (new_palette.depth == 8) + { + pp[i].red = *entry_start++; + pp[i].green = *entry_start++; + pp[i].blue = *entry_start++; + pp[i].alpha = *entry_start++; + } + else + { + pp[i].red = png_get_uint_16(entry_start); entry_start += 2; + pp[i].green = png_get_uint_16(entry_start); entry_start += 2; + pp[i].blue = png_get_uint_16(entry_start); entry_start += 2; + pp[i].alpha = png_get_uint_16(entry_start); entry_start += 2; + } + pp->frequency = png_get_uint_16(entry_start); entry_start += 2; + } +#endif + + /* Discard all chunk data except the name and stash that */ + new_palette.name = png_ptr->chunkdata; + + png_set_sPLT(png_ptr, info_ptr, &new_palette, 1); + + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = NULL; + png_free(png_ptr, new_palette.entries); +} +#endif /* PNG_READ_sPLT_SUPPORTED */ + +#ifdef PNG_READ_tRNS_SUPPORTED +void /* PRIVATE */ +png_handle_tRNS(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) +{ + png_byte readbuf[PNG_MAX_PALETTE_LENGTH]; + + png_debug(1, "in png_handle_tRNS"); + + if (!(png_ptr->mode & PNG_HAVE_IHDR)) + png_error(png_ptr, "Missing IHDR before tRNS"); + else if (png_ptr->mode & PNG_HAVE_IDAT) + { + png_warning(png_ptr, "Invalid tRNS after IDAT"); + png_crc_finish(png_ptr, length); + return; + } + else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_tRNS)) + { + png_warning(png_ptr, "Duplicate tRNS chunk"); + png_crc_finish(png_ptr, length); + return; + } + + if (png_ptr->color_type == PNG_COLOR_TYPE_GRAY) + { + png_byte buf[2]; + + if (length != 2) + { + png_warning(png_ptr, "Incorrect tRNS chunk length"); + png_crc_finish(png_ptr, length); + return; + } + + png_crc_read(png_ptr, buf, 2); + png_ptr->num_trans = 1; + png_ptr->trans_color.gray = png_get_uint_16(buf); + } + else if (png_ptr->color_type == PNG_COLOR_TYPE_RGB) + { + png_byte buf[6]; + + if (length != 6) + { + png_warning(png_ptr, "Incorrect tRNS chunk length"); + png_crc_finish(png_ptr, length); + return; + } + png_crc_read(png_ptr, buf, (png_size_t)length); + png_ptr->num_trans = 1; + png_ptr->trans_color.red = png_get_uint_16(buf); + png_ptr->trans_color.green = png_get_uint_16(buf + 2); + png_ptr->trans_color.blue = png_get_uint_16(buf + 4); + } + else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) + { + if (!(png_ptr->mode & PNG_HAVE_PLTE)) + { + /* Should be an error, but we can cope with it. */ + png_warning(png_ptr, "Missing PLTE before tRNS"); + } + if (length > (png_uint_32)png_ptr->num_palette || + length > PNG_MAX_PALETTE_LENGTH) + { + png_warning(png_ptr, "Incorrect tRNS chunk length"); + png_crc_finish(png_ptr, length); + return; + } + if (length == 0) + { + png_warning(png_ptr, "Zero length tRNS chunk"); + png_crc_finish(png_ptr, length); + return; + } + png_crc_read(png_ptr, readbuf, (png_size_t)length); + png_ptr->num_trans = (png_uint_16)length; + } + else + { + png_warning(png_ptr, "tRNS chunk not allowed with alpha channel"); + png_crc_finish(png_ptr, length); + return; + } + + if (png_crc_finish(png_ptr, 0)) + { + png_ptr->num_trans = 0; + return; + } + + png_set_tRNS(png_ptr, info_ptr, readbuf, png_ptr->num_trans, + &(png_ptr->trans_color)); +} +#endif + +#ifdef PNG_READ_bKGD_SUPPORTED +void /* PRIVATE */ +png_handle_bKGD(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) +{ + png_size_t truelen; + png_byte buf[6]; + + png_debug(1, "in png_handle_bKGD"); + + if (!(png_ptr->mode & PNG_HAVE_IHDR)) + png_error(png_ptr, "Missing IHDR before bKGD"); + else if (png_ptr->mode & PNG_HAVE_IDAT) + { + png_warning(png_ptr, "Invalid bKGD after IDAT"); + png_crc_finish(png_ptr, length); + return; + } + else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE && + !(png_ptr->mode & PNG_HAVE_PLTE)) + { + png_warning(png_ptr, "Missing PLTE before bKGD"); + png_crc_finish(png_ptr, length); + return; + } + else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_bKGD)) + { + png_warning(png_ptr, "Duplicate bKGD chunk"); + png_crc_finish(png_ptr, length); + return; + } + + if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) + truelen = 1; + else if (png_ptr->color_type & PNG_COLOR_MASK_COLOR) + truelen = 6; + else + truelen = 2; + + if (length != truelen) + { + png_warning(png_ptr, "Incorrect bKGD chunk length"); + png_crc_finish(png_ptr, length); + return; + } + + png_crc_read(png_ptr, buf, truelen); + if (png_crc_finish(png_ptr, 0)) + return; + + /* We convert the index value into RGB components so that we can allow + * arbitrary RGB values for background when we have transparency, and + * so it is easy to determine the RGB values of the background color + * from the info_ptr struct. */ + if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) + { + png_ptr->background.index = buf[0]; + if (info_ptr && info_ptr->num_palette) + { + if (buf[0] >= info_ptr->num_palette) + { + png_warning(png_ptr, "Incorrect bKGD chunk index value"); + return; + } + png_ptr->background.red = + (png_uint_16)png_ptr->palette[buf[0]].red; + png_ptr->background.green = + (png_uint_16)png_ptr->palette[buf[0]].green; + png_ptr->background.blue = + (png_uint_16)png_ptr->palette[buf[0]].blue; + } + } + else if (!(png_ptr->color_type & PNG_COLOR_MASK_COLOR)) /* GRAY */ + { + png_ptr->background.red = + png_ptr->background.green = + png_ptr->background.blue = + png_ptr->background.gray = png_get_uint_16(buf); + } + else + { + png_ptr->background.red = png_get_uint_16(buf); + png_ptr->background.green = png_get_uint_16(buf + 2); + png_ptr->background.blue = png_get_uint_16(buf + 4); + } + + png_set_bKGD(png_ptr, info_ptr, &(png_ptr->background)); +} +#endif + +#ifdef PNG_READ_hIST_SUPPORTED +void /* PRIVATE */ +png_handle_hIST(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) +{ + unsigned int num, i; + png_uint_16 readbuf[PNG_MAX_PALETTE_LENGTH]; + + png_debug(1, "in png_handle_hIST"); + + if (!(png_ptr->mode & PNG_HAVE_IHDR)) + png_error(png_ptr, "Missing IHDR before hIST"); + else if (png_ptr->mode & PNG_HAVE_IDAT) + { + png_warning(png_ptr, "Invalid hIST after IDAT"); + png_crc_finish(png_ptr, length); + return; + } + else if (!(png_ptr->mode & PNG_HAVE_PLTE)) + { + png_warning(png_ptr, "Missing PLTE before hIST"); + png_crc_finish(png_ptr, length); + return; + } + else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_hIST)) + { + png_warning(png_ptr, "Duplicate hIST chunk"); + png_crc_finish(png_ptr, length); + return; + } + + num = length / 2 ; + if (num != (unsigned int) png_ptr->num_palette || num > + (unsigned int) PNG_MAX_PALETTE_LENGTH) + { + png_warning(png_ptr, "Incorrect hIST chunk length"); + png_crc_finish(png_ptr, length); + return; + } + + for (i = 0; i < num; i++) + { + png_byte buf[2]; + + png_crc_read(png_ptr, buf, 2); + readbuf[i] = png_get_uint_16(buf); + } + + if (png_crc_finish(png_ptr, 0)) + return; + + png_set_hIST(png_ptr, info_ptr, readbuf); +} +#endif + +#ifdef PNG_READ_pHYs_SUPPORTED +void /* PRIVATE */ +png_handle_pHYs(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) +{ + png_byte buf[9]; + png_uint_32 res_x, res_y; + int unit_type; + + png_debug(1, "in png_handle_pHYs"); + + if (!(png_ptr->mode & PNG_HAVE_IHDR)) + png_error(png_ptr, "Missing IHDR before pHYs"); + else if (png_ptr->mode & PNG_HAVE_IDAT) + { + png_warning(png_ptr, "Invalid pHYs after IDAT"); + png_crc_finish(png_ptr, length); + return; + } + else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs)) + { + png_warning(png_ptr, "Duplicate pHYs chunk"); + png_crc_finish(png_ptr, length); + return; + } + + if (length != 9) + { + png_warning(png_ptr, "Incorrect pHYs chunk length"); + png_crc_finish(png_ptr, length); + return; + } + + png_crc_read(png_ptr, buf, 9); + if (png_crc_finish(png_ptr, 0)) + return; + + res_x = png_get_uint_32(buf); + res_y = png_get_uint_32(buf + 4); + unit_type = buf[8]; + png_set_pHYs(png_ptr, info_ptr, res_x, res_y, unit_type); +} +#endif + +#ifdef PNG_READ_oFFs_SUPPORTED +void /* PRIVATE */ +png_handle_oFFs(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) +{ + png_byte buf[9]; + png_int_32 offset_x, offset_y; + int unit_type; + + png_debug(1, "in png_handle_oFFs"); + + if (!(png_ptr->mode & PNG_HAVE_IHDR)) + png_error(png_ptr, "Missing IHDR before oFFs"); + else if (png_ptr->mode & PNG_HAVE_IDAT) + { + png_warning(png_ptr, "Invalid oFFs after IDAT"); + png_crc_finish(png_ptr, length); + return; + } + else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs)) + { + png_warning(png_ptr, "Duplicate oFFs chunk"); + png_crc_finish(png_ptr, length); + return; + } + + if (length != 9) + { + png_warning(png_ptr, "Incorrect oFFs chunk length"); + png_crc_finish(png_ptr, length); + return; + } + + png_crc_read(png_ptr, buf, 9); + if (png_crc_finish(png_ptr, 0)) + return; + + offset_x = png_get_int_32(buf); + offset_y = png_get_int_32(buf + 4); + unit_type = buf[8]; + png_set_oFFs(png_ptr, info_ptr, offset_x, offset_y, unit_type); +} +#endif + +#ifdef PNG_READ_pCAL_SUPPORTED +/* Read the pCAL chunk (described in the PNG Extensions document) */ +void /* PRIVATE */ +png_handle_pCAL(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) +{ + png_int_32 X0, X1; + png_byte type, nparams; + png_charp buf, units, endptr; + png_charpp params; + png_size_t slength; + int i; + + png_debug(1, "in png_handle_pCAL"); + + if (!(png_ptr->mode & PNG_HAVE_IHDR)) + png_error(png_ptr, "Missing IHDR before pCAL"); + else if (png_ptr->mode & PNG_HAVE_IDAT) + { + png_warning(png_ptr, "Invalid pCAL after IDAT"); + png_crc_finish(png_ptr, length); + return; + } + else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_pCAL)) + { + png_warning(png_ptr, "Duplicate pCAL chunk"); + png_crc_finish(png_ptr, length); + return; + } + + png_debug1(2, "Allocating and reading pCAL chunk data (%lu bytes)", + length + 1); + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = (png_charp)png_malloc_warn(png_ptr, length + 1); + if (png_ptr->chunkdata == NULL) + { + png_warning(png_ptr, "No memory for pCAL purpose"); + return; + } + slength = (png_size_t)length; + png_crc_read(png_ptr, (png_bytep)png_ptr->chunkdata, slength); + + if (png_crc_finish(png_ptr, 0)) + { + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = NULL; + return; + } + + png_ptr->chunkdata[slength] = 0x00; /* Null terminate the last string */ + + png_debug(3, "Finding end of pCAL purpose string"); + for (buf = png_ptr->chunkdata; *buf; buf++) + /* Empty loop */ ; + + endptr = png_ptr->chunkdata + slength; + + /* We need to have at least 12 bytes after the purpose string + in order to get the parameter information. */ + if (endptr <= buf + 12) + { + png_warning(png_ptr, "Invalid pCAL data"); + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = NULL; + return; + } + + png_debug(3, "Reading pCAL X0, X1, type, nparams, and units"); + X0 = png_get_int_32((png_bytep)buf+1); + X1 = png_get_int_32((png_bytep)buf+5); + type = buf[9]; + nparams = buf[10]; + units = buf + 11; + + png_debug(3, "Checking pCAL equation type and number of parameters"); + /* Check that we have the right number of parameters for known + equation types. */ + if ((type == PNG_EQUATION_LINEAR && nparams != 2) || + (type == PNG_EQUATION_BASE_E && nparams != 3) || + (type == PNG_EQUATION_ARBITRARY && nparams != 3) || + (type == PNG_EQUATION_HYPERBOLIC && nparams != 4)) + { + png_warning(png_ptr, "Invalid pCAL parameters for equation type"); + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = NULL; + return; + } + else if (type >= PNG_EQUATION_LAST) + { + png_warning(png_ptr, "Unrecognized equation type for pCAL chunk"); + } + + for (buf = units; *buf; buf++) + /* Empty loop to move past the units string. */ ; + + png_debug(3, "Allocating pCAL parameters array"); + params = (png_charpp)png_malloc_warn(png_ptr, + (png_size_t)(nparams * png_sizeof(png_charp))); + if (params == NULL) + { + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = NULL; + png_warning(png_ptr, "No memory for pCAL params"); + return; + } + + /* Get pointers to the start of each parameter string. */ + for (i = 0; i < (int)nparams; i++) + { + buf++; /* Skip the null string terminator from previous parameter. */ + + png_debug1(3, "Reading pCAL parameter %d", i); + for (params[i] = buf; buf <= endptr && *buf != 0x00; buf++) + /* Empty loop to move past each parameter string */ ; + + /* Make sure we haven't run out of data yet */ + if (buf > endptr) + { + png_warning(png_ptr, "Invalid pCAL data"); + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = NULL; + png_free(png_ptr, params); + return; + } + } + + png_set_pCAL(png_ptr, info_ptr, png_ptr->chunkdata, X0, X1, type, nparams, + units, params); + + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = NULL; + png_free(png_ptr, params); +} +#endif + +#ifdef PNG_READ_sCAL_SUPPORTED +/* Read the sCAL chunk */ +void /* PRIVATE */ +png_handle_sCAL(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) +{ + png_charp ep; +#ifdef PNG_FLOATING_POINT_SUPPORTED + double width, height; + png_charp vp; +#else +#ifdef PNG_FIXED_POINT_SUPPORTED + png_charp swidth, sheight; +#endif +#endif + png_size_t slength; + + png_debug(1, "in png_handle_sCAL"); + + if (!(png_ptr->mode & PNG_HAVE_IHDR)) + png_error(png_ptr, "Missing IHDR before sCAL"); + else if (png_ptr->mode & PNG_HAVE_IDAT) + { + png_warning(png_ptr, "Invalid sCAL after IDAT"); + png_crc_finish(png_ptr, length); + return; + } + else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_sCAL)) + { + png_warning(png_ptr, "Duplicate sCAL chunk"); + png_crc_finish(png_ptr, length); + return; + } + + png_debug1(2, "Allocating and reading sCAL chunk data (%lu bytes)", + length + 1); + png_ptr->chunkdata = (png_charp)png_malloc_warn(png_ptr, length + 1); + if (png_ptr->chunkdata == NULL) + { + png_warning(png_ptr, "Out of memory while processing sCAL chunk"); + png_crc_finish(png_ptr, length); + return; + } + slength = (png_size_t)length; + png_crc_read(png_ptr, (png_bytep)png_ptr->chunkdata, slength); + + if (png_crc_finish(png_ptr, 0)) + { + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = NULL; + return; + } + + png_ptr->chunkdata[slength] = 0x00; /* Null terminate the last string */ + + ep = png_ptr->chunkdata + 1; /* Skip unit byte */ + +#ifdef PNG_FLOATING_POINT_SUPPORTED + width = png_strtod(png_ptr, ep, &vp); + if (*vp) + { + png_warning(png_ptr, "malformed width string in sCAL chunk"); + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = NULL; + return; + } +#else +#ifdef PNG_FIXED_POINT_SUPPORTED + swidth = (png_charp)png_malloc_warn(png_ptr, png_strlen(ep) + 1); + if (swidth == NULL) + { + png_warning(png_ptr, "Out of memory while processing sCAL chunk width"); + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = NULL; + return; + } + png_memcpy(swidth, ep, png_strlen(ep)); +#endif +#endif + + for (ep = png_ptr->chunkdata; *ep; ep++) + /* Empty loop */ ; + ep++; + + if (png_ptr->chunkdata + slength < ep) + { + png_warning(png_ptr, "Truncated sCAL chunk"); +#if defined(PNG_FIXED_POINT_SUPPORTED) && !defined(PNG_FLOATING_POINT_SUPPORTED) + png_free(png_ptr, swidth); +#endif + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = NULL; + return; + } + +#ifdef PNG_FLOATING_POINT_SUPPORTED + height = png_strtod(png_ptr, ep, &vp); + if (*vp) + { + png_warning(png_ptr, "malformed height string in sCAL chunk"); + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = NULL; + return; + } +#else +#ifdef PNG_FIXED_POINT_SUPPORTED + sheight = (png_charp)png_malloc_warn(png_ptr, png_strlen(ep) + 1); + if (sheight == NULL) + { + png_warning(png_ptr, "Out of memory while processing sCAL chunk height"); + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = NULL; + png_free(png_ptr, swidth); + return; + } + png_memcpy(sheight, ep, png_strlen(ep)); +#endif +#endif + + if (png_ptr->chunkdata + slength < ep +#ifdef PNG_FLOATING_POINT_SUPPORTED + || width <= 0. || height <= 0. +#endif + ) + { + png_warning(png_ptr, "Invalid sCAL data"); + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = NULL; +#if defined(PNG_FIXED_POINT_SUPPORTED) && !defined(PNG_FLOATING_POINT_SUPPORTED) + png_free(png_ptr, swidth); + png_free(png_ptr, sheight); +#endif + return; + } + + +#ifdef PNG_FLOATING_POINT_SUPPORTED + png_set_sCAL(png_ptr, info_ptr, png_ptr->chunkdata[0], width, height); +#else +#ifdef PNG_FIXED_POINT_SUPPORTED + png_set_sCAL_s(png_ptr, info_ptr, png_ptr->chunkdata[0], swidth, sheight); +#endif +#endif + + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = NULL; +#if defined(PNG_FIXED_POINT_SUPPORTED) && !defined(PNG_FLOATING_POINT_SUPPORTED) + png_free(png_ptr, swidth); + png_free(png_ptr, sheight); +#endif +} +#endif + +#ifdef PNG_READ_tIME_SUPPORTED +void /* PRIVATE */ +png_handle_tIME(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) +{ + png_byte buf[7]; + png_time mod_time; + + png_debug(1, "in png_handle_tIME"); + + if (!(png_ptr->mode & PNG_HAVE_IHDR)) + png_error(png_ptr, "Out of place tIME chunk"); + else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_tIME)) + { + png_warning(png_ptr, "Duplicate tIME chunk"); + png_crc_finish(png_ptr, length); + return; + } + + if (png_ptr->mode & PNG_HAVE_IDAT) + png_ptr->mode |= PNG_AFTER_IDAT; + + if (length != 7) + { + png_warning(png_ptr, "Incorrect tIME chunk length"); + png_crc_finish(png_ptr, length); + return; + } + + png_crc_read(png_ptr, buf, 7); + if (png_crc_finish(png_ptr, 0)) + return; + + mod_time.second = buf[6]; + mod_time.minute = buf[5]; + mod_time.hour = buf[4]; + mod_time.day = buf[3]; + mod_time.month = buf[2]; + mod_time.year = png_get_uint_16(buf); + + png_set_tIME(png_ptr, info_ptr, &mod_time); +} +#endif + +#ifdef PNG_READ_tEXt_SUPPORTED +/* Note: this does not properly handle chunks that are > 64K under DOS */ +void /* PRIVATE */ +png_handle_tEXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) +{ + png_textp text_ptr; + png_charp key; + png_charp text; + png_uint_32 skip = 0; + png_size_t slength; + int ret; + + png_debug(1, "in png_handle_tEXt"); + +#ifdef PNG_USER_LIMITS_SUPPORTED + if (png_ptr->user_chunk_cache_max != 0) + { + if (png_ptr->user_chunk_cache_max == 1) + { + png_crc_finish(png_ptr, length); + return; + } + if (--png_ptr->user_chunk_cache_max == 1) + { + png_warning(png_ptr, "No space in chunk cache for tEXt"); + png_crc_finish(png_ptr, length); + return; + } + } +#endif + + if (!(png_ptr->mode & PNG_HAVE_IHDR)) + png_error(png_ptr, "Missing IHDR before tEXt"); + + if (png_ptr->mode & PNG_HAVE_IDAT) + png_ptr->mode |= PNG_AFTER_IDAT; + +#ifdef PNG_MAX_MALLOC_64K + if (length > (png_uint_32)65535L) + { + png_warning(png_ptr, "tEXt chunk too large to fit in memory"); + skip = length - (png_uint_32)65535L; + length = (png_uint_32)65535L; + } +#endif + + png_free(png_ptr, png_ptr->chunkdata); + + png_ptr->chunkdata = (png_charp)png_malloc_warn(png_ptr, length + 1); + if (png_ptr->chunkdata == NULL) + { + png_warning(png_ptr, "No memory to process text chunk"); + return; + } + slength = (png_size_t)length; + png_crc_read(png_ptr, (png_bytep)png_ptr->chunkdata, slength); + + if (png_crc_finish(png_ptr, skip)) + { + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = NULL; + return; + } + + key = png_ptr->chunkdata; + + key[slength] = 0x00; + + for (text = key; *text; text++) + /* Empty loop to find end of key */ ; + + if (text != key + slength) + text++; + + text_ptr = (png_textp)png_malloc_warn(png_ptr, + png_sizeof(png_text)); + if (text_ptr == NULL) + { + png_warning(png_ptr, "Not enough memory to process text chunk"); + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = NULL; + return; + } + text_ptr->compression = PNG_TEXT_COMPRESSION_NONE; + text_ptr->key = key; +#ifdef PNG_iTXt_SUPPORTED + text_ptr->lang = NULL; + text_ptr->lang_key = NULL; + text_ptr->itxt_length = 0; +#endif + text_ptr->text = text; + text_ptr->text_length = png_strlen(text); + + ret = png_set_text_2(png_ptr, info_ptr, text_ptr, 1); + + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = NULL; + png_free(png_ptr, text_ptr); + if (ret) + png_warning(png_ptr, "Insufficient memory to process text chunk"); +} +#endif + +#ifdef PNG_READ_zTXt_SUPPORTED +/* Note: this does not correctly handle chunks that are > 64K under DOS */ +void /* PRIVATE */ +png_handle_zTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) +{ + png_textp text_ptr; + png_charp text; + int comp_type; + int ret; + png_size_t slength, prefix_len, data_len; + + png_debug(1, "in png_handle_zTXt"); + +#ifdef PNG_USER_LIMITS_SUPPORTED + if (png_ptr->user_chunk_cache_max != 0) + { + if (png_ptr->user_chunk_cache_max == 1) + { + png_crc_finish(png_ptr, length); + return; + } + if (--png_ptr->user_chunk_cache_max == 1) + { + png_warning(png_ptr, "No space in chunk cache for zTXt"); + png_crc_finish(png_ptr, length); + return; + } + } +#endif + + if (!(png_ptr->mode & PNG_HAVE_IHDR)) + png_error(png_ptr, "Missing IHDR before zTXt"); + + if (png_ptr->mode & PNG_HAVE_IDAT) + png_ptr->mode |= PNG_AFTER_IDAT; + +#ifdef PNG_MAX_MALLOC_64K + /* We will no doubt have problems with chunks even half this size, but + there is no hard and fast rule to tell us where to stop. */ + if (length > (png_uint_32)65535L) + { + png_warning(png_ptr, "zTXt chunk too large to fit in memory"); + png_crc_finish(png_ptr, length); + return; + } +#endif + + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = (png_charp)png_malloc_warn(png_ptr, length + 1); + if (png_ptr->chunkdata == NULL) + { + png_warning(png_ptr, "Out of memory processing zTXt chunk"); + return; + } + slength = (png_size_t)length; + png_crc_read(png_ptr, (png_bytep)png_ptr->chunkdata, slength); + if (png_crc_finish(png_ptr, 0)) + { + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = NULL; + return; + } + + png_ptr->chunkdata[slength] = 0x00; + + for (text = png_ptr->chunkdata; *text; text++) + /* Empty loop */ ; + + /* zTXt must have some text after the chunkdataword */ + if (text >= png_ptr->chunkdata + slength - 2) + { + png_warning(png_ptr, "Truncated zTXt chunk"); + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = NULL; + return; + } + else + { + comp_type = *(++text); + if (comp_type != PNG_TEXT_COMPRESSION_zTXt) + { + png_warning(png_ptr, "Unknown compression type in zTXt chunk"); + comp_type = PNG_TEXT_COMPRESSION_zTXt; + } + text++; /* Skip the compression_method byte */ + } + prefix_len = text - png_ptr->chunkdata; + + png_decompress_chunk(png_ptr, comp_type, + (png_size_t)length, prefix_len, &data_len); + + text_ptr = (png_textp)png_malloc_warn(png_ptr, + png_sizeof(png_text)); + if (text_ptr == NULL) + { + png_warning(png_ptr, "Not enough memory to process zTXt chunk"); + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = NULL; + return; + } + text_ptr->compression = comp_type; + text_ptr->key = png_ptr->chunkdata; +#ifdef PNG_iTXt_SUPPORTED + text_ptr->lang = NULL; + text_ptr->lang_key = NULL; + text_ptr->itxt_length = 0; +#endif + text_ptr->text = png_ptr->chunkdata + prefix_len; + text_ptr->text_length = data_len; + + ret = png_set_text_2(png_ptr, info_ptr, text_ptr, 1); + + png_free(png_ptr, text_ptr); + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = NULL; + if (ret) + png_error(png_ptr, "Insufficient memory to store zTXt chunk"); +} +#endif + +#ifdef PNG_READ_iTXt_SUPPORTED +/* Note: this does not correctly handle chunks that are > 64K under DOS */ +void /* PRIVATE */ +png_handle_iTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) +{ + png_textp text_ptr; + png_charp key, lang, text, lang_key; + int comp_flag; + int comp_type = 0; + int ret; + png_size_t slength, prefix_len, data_len; + + png_debug(1, "in png_handle_iTXt"); + +#ifdef PNG_USER_LIMITS_SUPPORTED + if (png_ptr->user_chunk_cache_max != 0) + { + if (png_ptr->user_chunk_cache_max == 1) + { + png_crc_finish(png_ptr, length); + return; + } + if (--png_ptr->user_chunk_cache_max == 1) + { + png_warning(png_ptr, "No space in chunk cache for iTXt"); + png_crc_finish(png_ptr, length); + return; + } + } +#endif + + if (!(png_ptr->mode & PNG_HAVE_IHDR)) + png_error(png_ptr, "Missing IHDR before iTXt"); + + if (png_ptr->mode & PNG_HAVE_IDAT) + png_ptr->mode |= PNG_AFTER_IDAT; + +#ifdef PNG_MAX_MALLOC_64K + /* We will no doubt have problems with chunks even half this size, but + there is no hard and fast rule to tell us where to stop. */ + if (length > (png_uint_32)65535L) + { + png_warning(png_ptr, "iTXt chunk too large to fit in memory"); + png_crc_finish(png_ptr, length); + return; + } +#endif + + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = (png_charp)png_malloc_warn(png_ptr, length + 1); + if (png_ptr->chunkdata == NULL) + { + png_warning(png_ptr, "No memory to process iTXt chunk"); + return; + } + slength = (png_size_t)length; + png_crc_read(png_ptr, (png_bytep)png_ptr->chunkdata, slength); + if (png_crc_finish(png_ptr, 0)) + { + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = NULL; + return; + } + + png_ptr->chunkdata[slength] = 0x00; + + for (lang = png_ptr->chunkdata; *lang; lang++) + /* Empty loop */ ; + lang++; /* Skip NUL separator */ + + /* iTXt must have a language tag (possibly empty), two compression bytes, + * translated keyword (possibly empty), and possibly some text after the + * keyword + */ + + if (lang >= png_ptr->chunkdata + slength - 3) + { + png_warning(png_ptr, "Truncated iTXt chunk"); + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = NULL; + return; + } + else + { + comp_flag = *lang++; + comp_type = *lang++; + } + + for (lang_key = lang; *lang_key; lang_key++) + /* Empty loop */ ; + lang_key++; /* Skip NUL separator */ + + if (lang_key >= png_ptr->chunkdata + slength) + { + png_warning(png_ptr, "Truncated iTXt chunk"); + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = NULL; + return; + } + + for (text = lang_key; *text; text++) + /* Empty loop */ ; + text++; /* Skip NUL separator */ + if (text >= png_ptr->chunkdata + slength) + { + png_warning(png_ptr, "Malformed iTXt chunk"); + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = NULL; + return; + } + + prefix_len = text - png_ptr->chunkdata; + + key=png_ptr->chunkdata; + if (comp_flag) + png_decompress_chunk(png_ptr, comp_type, + (size_t)length, prefix_len, &data_len); + else + data_len = png_strlen(png_ptr->chunkdata + prefix_len); + text_ptr = (png_textp)png_malloc_warn(png_ptr, + png_sizeof(png_text)); + if (text_ptr == NULL) + { + png_warning(png_ptr, "Not enough memory to process iTXt chunk"); + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = NULL; + return; + } + text_ptr->compression = (int)comp_flag + 1; + text_ptr->lang_key = png_ptr->chunkdata + (lang_key - key); + text_ptr->lang = png_ptr->chunkdata + (lang - key); + text_ptr->itxt_length = data_len; + text_ptr->text_length = 0; + text_ptr->key = png_ptr->chunkdata; + text_ptr->text = png_ptr->chunkdata + prefix_len; + + ret = png_set_text_2(png_ptr, info_ptr, text_ptr, 1); + + png_free(png_ptr, text_ptr); + png_free(png_ptr, png_ptr->chunkdata); + png_ptr->chunkdata = NULL; + if (ret) + png_error(png_ptr, "Insufficient memory to store iTXt chunk"); +} +#endif + +/* This function is called when we haven't found a handler for a + chunk. If there isn't a problem with the chunk itself (ie bad + chunk name, CRC, or a critical chunk), the chunk is silently ignored + -- unless the PNG_FLAG_UNKNOWN_CHUNKS_SUPPORTED flag is on in which + case it will be saved away to be written out later. */ +void /* PRIVATE */ +png_handle_unknown(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) +{ + png_uint_32 skip = 0; + + png_debug(1, "in png_handle_unknown"); + +#ifdef PNG_USER_LIMITS_SUPPORTED + if (png_ptr->user_chunk_cache_max != 0) + { + if (png_ptr->user_chunk_cache_max == 1) + { + png_crc_finish(png_ptr, length); + return; + } + if (--png_ptr->user_chunk_cache_max == 1) + { + png_warning(png_ptr, "No space in chunk cache for unknown chunk"); + png_crc_finish(png_ptr, length); + return; + } + } +#endif + + if (png_ptr->mode & PNG_HAVE_IDAT) + { + PNG_IDAT; + if (png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) /* Not an IDAT */ + png_ptr->mode |= PNG_AFTER_IDAT; + } + + if (!(png_ptr->chunk_name[0] & 0x20)) + { +#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED + if (png_handle_as_unknown(png_ptr, png_ptr->chunk_name) != + PNG_HANDLE_CHUNK_ALWAYS +#ifdef PNG_READ_USER_CHUNKS_SUPPORTED + && png_ptr->read_user_chunk_fn == NULL +#endif + ) +#endif + png_chunk_error(png_ptr, "unknown critical chunk"); + } + +#ifdef PNG_READ_UNKNOWN_CHUNKS_SUPPORTED + if ((png_ptr->flags & PNG_FLAG_KEEP_UNKNOWN_CHUNKS) +#ifdef PNG_READ_USER_CHUNKS_SUPPORTED + || (png_ptr->read_user_chunk_fn != NULL) +#endif + ) + { +#ifdef PNG_MAX_MALLOC_64K + if (length > (png_uint_32)65535L) + { + png_warning(png_ptr, "unknown chunk too large to fit in memory"); + skip = length - (png_uint_32)65535L; + length = (png_uint_32)65535L; + } +#endif + png_memcpy((png_charp)png_ptr->unknown_chunk.name, + (png_charp)png_ptr->chunk_name, + png_sizeof(png_ptr->unknown_chunk.name)); + png_ptr->unknown_chunk.name[png_sizeof(png_ptr->unknown_chunk.name)-1] + = '\0'; + png_ptr->unknown_chunk.size = (png_size_t)length; + if (length == 0) + png_ptr->unknown_chunk.data = NULL; + else + { + png_ptr->unknown_chunk.data = (png_bytep)png_malloc(png_ptr, length); + png_crc_read(png_ptr, (png_bytep)png_ptr->unknown_chunk.data, length); + } +#ifdef PNG_READ_USER_CHUNKS_SUPPORTED + if (png_ptr->read_user_chunk_fn != NULL) + { + /* Callback to user unknown chunk handler */ + int ret; + ret = (*(png_ptr->read_user_chunk_fn)) + (png_ptr, &png_ptr->unknown_chunk); + if (ret < 0) + png_chunk_error(png_ptr, "error in user chunk"); + if (ret == 0) + { + if (!(png_ptr->chunk_name[0] & 0x20)) +#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED + if (png_handle_as_unknown(png_ptr, png_ptr->chunk_name) != + PNG_HANDLE_CHUNK_ALWAYS) +#endif + png_chunk_error(png_ptr, "unknown critical chunk"); + png_set_unknown_chunks(png_ptr, info_ptr, + &png_ptr->unknown_chunk, 1); + } + } + else +#endif + png_set_unknown_chunks(png_ptr, info_ptr, &png_ptr->unknown_chunk, 1); + png_free(png_ptr, png_ptr->unknown_chunk.data); + png_ptr->unknown_chunk.data = NULL; + } + else +#endif + skip = length; + + png_crc_finish(png_ptr, skip); + +#ifndef PNG_READ_USER_CHUNKS_SUPPORTED + info_ptr = info_ptr; /* Quiet compiler warnings about unused info_ptr */ +#endif +} + +/* This function is called to verify that a chunk name is valid. + This function can't have the "critical chunk check" incorporated + into it, since in the future we will need to be able to call user + functions to handle unknown critical chunks after we check that + the chunk name itself is valid. */ + +#define isnonalpha(c) ((c) < 65 || (c) > 122 || ((c) > 90 && (c) < 97)) + +void /* PRIVATE */ +png_check_chunk_name(png_structp png_ptr, png_bytep chunk_name) +{ + png_debug(1, "in png_check_chunk_name"); + if (isnonalpha(chunk_name[0]) || isnonalpha(chunk_name[1]) || + isnonalpha(chunk_name[2]) || isnonalpha(chunk_name[3])) + { + png_chunk_error(png_ptr, "invalid chunk type"); + } +} + +/* Combines the row recently read in with the existing pixels in the + row. This routine takes care of alpha and transparency if requested. + This routine also handles the two methods of progressive display + of interlaced images, depending on the mask value. + The mask value describes which pixels are to be combined with + the row. The pattern always repeats every 8 pixels, so just 8 + bits are needed. A one indicates the pixel is to be combined, + a zero indicates the pixel is to be skipped. This is in addition + to any alpha or transparency value associated with the pixel. If + you want all pixels to be combined, pass 0xff (255) in mask. */ + +void /* PRIVATE */ +png_combine_row(png_structp png_ptr, png_bytep row, int mask) +{ + png_debug(1, "in png_combine_row"); + if (mask == 0xff) + { + png_memcpy(row, png_ptr->row_buf + 1, + PNG_ROWBYTES(png_ptr->row_info.pixel_depth, png_ptr->width)); + } + else + { + switch (png_ptr->row_info.pixel_depth) + { + case 1: + { + png_bytep sp = png_ptr->row_buf + 1; + png_bytep dp = row; + int s_inc, s_start, s_end; + int m = 0x80; + int shift; + png_uint_32 i; + png_uint_32 row_width = png_ptr->width; + +#ifdef PNG_READ_PACKSWAP_SUPPORTED + if (png_ptr->transformations & PNG_PACKSWAP) + { + s_start = 0; + s_end = 7; + s_inc = 1; + } + else +#endif + { + s_start = 7; + s_end = 0; + s_inc = -1; + } + + shift = s_start; + + for (i = 0; i < row_width; i++) + { + if (m & mask) + { + int value; + + value = (*sp >> shift) & 0x01; + *dp &= (png_byte)((0x7f7f >> (7 - shift)) & 0xff); + *dp |= (png_byte)(value << shift); + } + + if (shift == s_end) + { + shift = s_start; + sp++; + dp++; + } + else + shift += s_inc; + + if (m == 1) + m = 0x80; + else + m >>= 1; + } + break; + } + case 2: + { + png_bytep sp = png_ptr->row_buf + 1; + png_bytep dp = row; + int s_start, s_end, s_inc; + int m = 0x80; + int shift; + png_uint_32 i; + png_uint_32 row_width = png_ptr->width; + int value; + +#ifdef PNG_READ_PACKSWAP_SUPPORTED + if (png_ptr->transformations & PNG_PACKSWAP) + { + s_start = 0; + s_end = 6; + s_inc = 2; + } + else +#endif + { + s_start = 6; + s_end = 0; + s_inc = -2; + } + + shift = s_start; + + for (i = 0; i < row_width; i++) + { + if (m & mask) + { + value = (*sp >> shift) & 0x03; + *dp &= (png_byte)((0x3f3f >> (6 - shift)) & 0xff); + *dp |= (png_byte)(value << shift); + } + + if (shift == s_end) + { + shift = s_start; + sp++; + dp++; + } + else + shift += s_inc; + if (m == 1) + m = 0x80; + else + m >>= 1; + } + break; + } + case 4: + { + png_bytep sp = png_ptr->row_buf + 1; + png_bytep dp = row; + int s_start, s_end, s_inc; + int m = 0x80; + int shift; + png_uint_32 i; + png_uint_32 row_width = png_ptr->width; + int value; + +#ifdef PNG_READ_PACKSWAP_SUPPORTED + if (png_ptr->transformations & PNG_PACKSWAP) + { + s_start = 0; + s_end = 4; + s_inc = 4; + } + else +#endif + { + s_start = 4; + s_end = 0; + s_inc = -4; + } + shift = s_start; + + for (i = 0; i < row_width; i++) + { + if (m & mask) + { + value = (*sp >> shift) & 0xf; + *dp &= (png_byte)((0xf0f >> (4 - shift)) & 0xff); + *dp |= (png_byte)(value << shift); + } + + if (shift == s_end) + { + shift = s_start; + sp++; + dp++; + } + else + shift += s_inc; + if (m == 1) + m = 0x80; + else + m >>= 1; + } + break; + } + default: + { + png_bytep sp = png_ptr->row_buf + 1; + png_bytep dp = row; + png_size_t pixel_bytes = (png_ptr->row_info.pixel_depth >> 3); + png_uint_32 i; + png_uint_32 row_width = png_ptr->width; + png_byte m = 0x80; + + + for (i = 0; i < row_width; i++) + { + if (m & mask) + { + png_memcpy(dp, sp, pixel_bytes); + } + + sp += pixel_bytes; + dp += pixel_bytes; + + if (m == 1) + m = 0x80; + else + m >>= 1; + } + break; + } + } + } +} + +#ifdef PNG_READ_INTERLACING_SUPPORTED +/* OLD pre-1.0.9 interface: +void png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass, + png_uint_32 transformations) + */ +void /* PRIVATE */ +png_do_read_interlace(png_structp png_ptr) +{ + png_row_infop row_info = &(png_ptr->row_info); + png_bytep row = png_ptr->row_buf + 1; + int pass = png_ptr->pass; + png_uint_32 transformations = png_ptr->transformations; + /* Arrays to facilitate easy interlacing - use pass (0 - 6) as index */ + /* Offset to next interlace block */ + PNG_CONST int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1}; + + png_debug(1, "in png_do_read_interlace"); + if (row != NULL && row_info != NULL) + { + png_uint_32 final_width; + + final_width = row_info->width * png_pass_inc[pass]; + + switch (row_info->pixel_depth) + { + case 1: + { + png_bytep sp = row + (png_size_t)((row_info->width - 1) >> 3); + png_bytep dp = row + (png_size_t)((final_width - 1) >> 3); + int sshift, dshift; + int s_start, s_end, s_inc; + int jstop = png_pass_inc[pass]; + png_byte v; + png_uint_32 i; + int j; + +#ifdef PNG_READ_PACKSWAP_SUPPORTED + if (transformations & PNG_PACKSWAP) + { + sshift = (int)((row_info->width + 7) & 0x07); + dshift = (int)((final_width + 7) & 0x07); + s_start = 7; + s_end = 0; + s_inc = -1; + } + else +#endif + { + sshift = 7 - (int)((row_info->width + 7) & 0x07); + dshift = 7 - (int)((final_width + 7) & 0x07); + s_start = 0; + s_end = 7; + s_inc = 1; + } + + for (i = 0; i < row_info->width; i++) + { + v = (png_byte)((*sp >> sshift) & 0x01); + for (j = 0; j < jstop; j++) + { + *dp &= (png_byte)((0x7f7f >> (7 - dshift)) & 0xff); + *dp |= (png_byte)(v << dshift); + if (dshift == s_end) + { + dshift = s_start; + dp--; + } + else + dshift += s_inc; + } + if (sshift == s_end) + { + sshift = s_start; + sp--; + } + else + sshift += s_inc; + } + break; + } + case 2: + { + png_bytep sp = row + (png_uint_32)((row_info->width - 1) >> 2); + png_bytep dp = row + (png_uint_32)((final_width - 1) >> 2); + int sshift, dshift; + int s_start, s_end, s_inc; + int jstop = png_pass_inc[pass]; + png_uint_32 i; + +#ifdef PNG_READ_PACKSWAP_SUPPORTED + if (transformations & PNG_PACKSWAP) + { + sshift = (int)(((row_info->width + 3) & 0x03) << 1); + dshift = (int)(((final_width + 3) & 0x03) << 1); + s_start = 6; + s_end = 0; + s_inc = -2; + } + else +#endif + { + sshift = (int)((3 - ((row_info->width + 3) & 0x03)) << 1); + dshift = (int)((3 - ((final_width + 3) & 0x03)) << 1); + s_start = 0; + s_end = 6; + s_inc = 2; + } + + for (i = 0; i < row_info->width; i++) + { + png_byte v; + int j; + + v = (png_byte)((*sp >> sshift) & 0x03); + for (j = 0; j < jstop; j++) + { + *dp &= (png_byte)((0x3f3f >> (6 - dshift)) & 0xff); + *dp |= (png_byte)(v << dshift); + if (dshift == s_end) + { + dshift = s_start; + dp--; + } + else + dshift += s_inc; + } + if (sshift == s_end) + { + sshift = s_start; + sp--; + } + else + sshift += s_inc; + } + break; + } + case 4: + { + png_bytep sp = row + (png_size_t)((row_info->width - 1) >> 1); + png_bytep dp = row + (png_size_t)((final_width - 1) >> 1); + int sshift, dshift; + int s_start, s_end, s_inc; + png_uint_32 i; + int jstop = png_pass_inc[pass]; + +#ifdef PNG_READ_PACKSWAP_SUPPORTED + if (transformations & PNG_PACKSWAP) + { + sshift = (int)(((row_info->width + 1) & 0x01) << 2); + dshift = (int)(((final_width + 1) & 0x01) << 2); + s_start = 4; + s_end = 0; + s_inc = -4; + } + else +#endif + { + sshift = (int)((1 - ((row_info->width + 1) & 0x01)) << 2); + dshift = (int)((1 - ((final_width + 1) & 0x01)) << 2); + s_start = 0; + s_end = 4; + s_inc = 4; + } + + for (i = 0; i < row_info->width; i++) + { + png_byte v = (png_byte)((*sp >> sshift) & 0xf); + int j; + + for (j = 0; j < jstop; j++) + { + *dp &= (png_byte)((0xf0f >> (4 - dshift)) & 0xff); + *dp |= (png_byte)(v << dshift); + if (dshift == s_end) + { + dshift = s_start; + dp--; + } + else + dshift += s_inc; + } + if (sshift == s_end) + { + sshift = s_start; + sp--; + } + else + sshift += s_inc; + } + break; + } + default: + { + png_size_t pixel_bytes = (row_info->pixel_depth >> 3); + png_bytep sp = row + (png_size_t)(row_info->width - 1) + * pixel_bytes; + png_bytep dp = row + (png_size_t)(final_width - 1) * pixel_bytes; + + int jstop = png_pass_inc[pass]; + png_uint_32 i; + + for (i = 0; i < row_info->width; i++) + { + png_byte v[8]; + int j; + + png_memcpy(v, sp, pixel_bytes); + for (j = 0; j < jstop; j++) + { + png_memcpy(dp, v, pixel_bytes); + dp -= pixel_bytes; + } + sp -= pixel_bytes; + } + break; + } + } + row_info->width = final_width; + row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth, final_width); + } +#ifndef PNG_READ_PACKSWAP_SUPPORTED + transformations = transformations; /* Silence compiler warning */ +#endif +} +#endif /* PNG_READ_INTERLACING_SUPPORTED */ + +void /* PRIVATE */ +png_read_filter_row(png_structp png_ptr, png_row_infop row_info, png_bytep row, + png_bytep prev_row, int filter) +{ + png_debug(1, "in png_read_filter_row"); + png_debug2(2, "row = %lu, filter = %d", png_ptr->row_number, filter); + switch (filter) + { + case PNG_FILTER_VALUE_NONE: + break; + case PNG_FILTER_VALUE_SUB: + { + png_uint_32 i; + png_uint_32 istop = row_info->rowbytes; + png_uint_32 bpp = (row_info->pixel_depth + 7) >> 3; + png_bytep rp = row + bpp; + png_bytep lp = row; + + for (i = bpp; i < istop; i++) + { + *rp = (png_byte)(((int)(*rp) + (int)(*lp++)) & 0xff); + rp++; + } + break; + } + case PNG_FILTER_VALUE_UP: + { + png_uint_32 i; + png_uint_32 istop = row_info->rowbytes; + png_bytep rp = row; + png_bytep pp = prev_row; + + for (i = 0; i < istop; i++) + { + *rp = (png_byte)(((int)(*rp) + (int)(*pp++)) & 0xff); + rp++; + } + break; + } + case PNG_FILTER_VALUE_AVG: + { + png_uint_32 i; + png_bytep rp = row; + png_bytep pp = prev_row; + png_bytep lp = row; + png_uint_32 bpp = (row_info->pixel_depth + 7) >> 3; + png_uint_32 istop = row_info->rowbytes - bpp; + + for (i = 0; i < bpp; i++) + { + *rp = (png_byte)(((int)(*rp) + + ((int)(*pp++) / 2 )) & 0xff); + rp++; + } + + for (i = 0; i < istop; i++) + { + *rp = (png_byte)(((int)(*rp) + + (int)(*pp++ + *lp++) / 2 ) & 0xff); + rp++; + } + break; + } + case PNG_FILTER_VALUE_PAETH: + { + png_uint_32 i; + png_bytep rp = row; + png_bytep pp = prev_row; + png_bytep lp = row; + png_bytep cp = prev_row; + png_uint_32 bpp = (row_info->pixel_depth + 7) >> 3; + png_uint_32 istop=row_info->rowbytes - bpp; + + for (i = 0; i < bpp; i++) + { + *rp = (png_byte)(((int)(*rp) + (int)(*pp++)) & 0xff); + rp++; + } + + for (i = 0; i < istop; i++) /* Use leftover rp,pp */ + { + int a, b, c, pa, pb, pc, p; + + a = *lp++; + b = *pp++; + c = *cp++; + + p = b - c; + pc = a - c; + +#ifdef PNG_USE_ABS + pa = abs(p); + pb = abs(pc); + pc = abs(p + pc); +#else + pa = p < 0 ? -p : p; + pb = pc < 0 ? -pc : pc; + pc = (p + pc) < 0 ? -(p + pc) : p + pc; +#endif + + /* + if (pa <= pb && pa <= pc) + p = a; + else if (pb <= pc) + p = b; + else + p = c; + */ + + p = (pa <= pb && pa <= pc) ? a : (pb <= pc) ? b : c; + + *rp = (png_byte)(((int)(*rp) + p) & 0xff); + rp++; + } + break; + } + default: + png_warning(png_ptr, "Ignoring bad adaptive filter type"); + *row = 0; + break; + } +} + +#ifdef PNG_SEQUENTIAL_READ_SUPPORTED +void /* PRIVATE */ +png_read_finish_row(png_structp png_ptr) +{ +#ifdef PNG_READ_INTERLACING_SUPPORTED + /* Arrays to facilitate easy interlacing - use pass (0 - 6) as index */ + + /* Start of interlace block */ + PNG_CONST int png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0}; + + /* Offset to next interlace block */ + PNG_CONST int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1}; + + /* Start of interlace block in the y direction */ + PNG_CONST int png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1}; + + /* Offset to next interlace block in the y direction */ + PNG_CONST int png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2}; +#endif /* PNG_READ_INTERLACING_SUPPORTED */ + + png_debug(1, "in png_read_finish_row"); + png_ptr->row_number++; + if (png_ptr->row_number < png_ptr->num_rows) + return; + +#ifdef PNG_READ_INTERLACING_SUPPORTED + if (png_ptr->interlaced) + { + png_ptr->row_number = 0; + png_memset(png_ptr->prev_row, 0, + png_ptr->rowbytes + 1); + do + { + png_ptr->pass++; + if (png_ptr->pass >= 7) + break; + png_ptr->iwidth = (png_ptr->width + + png_pass_inc[png_ptr->pass] - 1 - + png_pass_start[png_ptr->pass]) / + png_pass_inc[png_ptr->pass]; + + if (!(png_ptr->transformations & PNG_INTERLACE)) + { + png_ptr->num_rows = (png_ptr->height + + png_pass_yinc[png_ptr->pass] - 1 - + png_pass_ystart[png_ptr->pass]) / + png_pass_yinc[png_ptr->pass]; + if (!(png_ptr->num_rows)) + continue; + } + else /* if (png_ptr->transformations & PNG_INTERLACE) */ + break; + } while (png_ptr->iwidth == 0); + + if (png_ptr->pass < 7) + return; + } +#endif /* PNG_READ_INTERLACING_SUPPORTED */ + + if (!(png_ptr->flags & PNG_FLAG_ZLIB_FINISHED)) + { + PNG_IDAT; + char extra; + int ret; + + png_ptr->zstream.next_out = (Byte *)&extra; + png_ptr->zstream.avail_out = (uInt)1; + for (;;) + { + if (!(png_ptr->zstream.avail_in)) + { + while (!png_ptr->idat_size) + { + png_byte chunk_length[4]; + + png_crc_finish(png_ptr, 0); + + png_read_data(png_ptr, chunk_length, 4); + png_ptr->idat_size = png_get_uint_31(png_ptr, chunk_length); + png_reset_crc(png_ptr); + png_crc_read(png_ptr, png_ptr->chunk_name, 4); + if (png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) + png_error(png_ptr, "Not enough image data"); + + } + png_ptr->zstream.avail_in = (uInt)png_ptr->zbuf_size; + png_ptr->zstream.next_in = png_ptr->zbuf; + if (png_ptr->zbuf_size > png_ptr->idat_size) + png_ptr->zstream.avail_in = (uInt)png_ptr->idat_size; + png_crc_read(png_ptr, png_ptr->zbuf, png_ptr->zstream.avail_in); + png_ptr->idat_size -= png_ptr->zstream.avail_in; + } + ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH); + if (ret == Z_STREAM_END) + { + if (!(png_ptr->zstream.avail_out) || png_ptr->zstream.avail_in || + png_ptr->idat_size) + png_warning(png_ptr, "Extra compressed data"); + png_ptr->mode |= PNG_AFTER_IDAT; + png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED; + break; + } + if (ret != Z_OK) + png_error(png_ptr, png_ptr->zstream.msg ? png_ptr->zstream.msg : + "Decompression Error"); + + if (!(png_ptr->zstream.avail_out)) + { + png_warning(png_ptr, "Extra compressed data"); + png_ptr->mode |= PNG_AFTER_IDAT; + png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED; + break; + } + + } + png_ptr->zstream.avail_out = 0; + } + + if (png_ptr->idat_size || png_ptr->zstream.avail_in) + png_warning(png_ptr, "Extra compression data"); + + inflateReset(&png_ptr->zstream); + + png_ptr->mode |= PNG_AFTER_IDAT; +} +#endif /* PNG_SEQUENTIAL_READ_SUPPORTED */ + +void /* PRIVATE */ +png_read_start_row(png_structp png_ptr) +{ +#ifdef PNG_READ_INTERLACING_SUPPORTED + /* Arrays to facilitate easy interlacing - use pass (0 - 6) as index */ + + /* Start of interlace block */ + PNG_CONST int png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0}; + + /* Offset to next interlace block */ + PNG_CONST int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1}; + + /* Start of interlace block in the y direction */ + PNG_CONST int png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1}; + + /* Offset to next interlace block in the y direction */ + PNG_CONST int png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2}; +#endif + + int max_pixel_depth; + png_size_t row_bytes; + + png_debug(1, "in png_read_start_row"); + png_ptr->zstream.avail_in = 0; + png_init_read_transformations(png_ptr); +#ifdef PNG_READ_INTERLACING_SUPPORTED + if (png_ptr->interlaced) + { + if (!(png_ptr->transformations & PNG_INTERLACE)) + png_ptr->num_rows = (png_ptr->height + png_pass_yinc[0] - 1 - + png_pass_ystart[0]) / png_pass_yinc[0]; + else + png_ptr->num_rows = png_ptr->height; + + png_ptr->iwidth = (png_ptr->width + + png_pass_inc[png_ptr->pass] - 1 - + png_pass_start[png_ptr->pass]) / + png_pass_inc[png_ptr->pass]; + } + else +#endif /* PNG_READ_INTERLACING_SUPPORTED */ + { + png_ptr->num_rows = png_ptr->height; + png_ptr->iwidth = png_ptr->width; + } + max_pixel_depth = png_ptr->pixel_depth; + +#ifdef PNG_READ_PACK_SUPPORTED + if ((png_ptr->transformations & PNG_PACK) && png_ptr->bit_depth < 8) + max_pixel_depth = 8; +#endif + +#ifdef PNG_READ_EXPAND_SUPPORTED + if (png_ptr->transformations & PNG_EXPAND) + { + if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) + { + if (png_ptr->num_trans) + max_pixel_depth = 32; + else + max_pixel_depth = 24; + } + else if (png_ptr->color_type == PNG_COLOR_TYPE_GRAY) + { + if (max_pixel_depth < 8) + max_pixel_depth = 8; + if (png_ptr->num_trans) + max_pixel_depth *= 2; + } + else if (png_ptr->color_type == PNG_COLOR_TYPE_RGB) + { + if (png_ptr->num_trans) + { + max_pixel_depth *= 4; + max_pixel_depth /= 3; + } + } + } +#endif + +#ifdef PNG_READ_FILLER_SUPPORTED + if (png_ptr->transformations & (PNG_FILLER)) + { + if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) + max_pixel_depth = 32; + else if (png_ptr->color_type == PNG_COLOR_TYPE_GRAY) + { + if (max_pixel_depth <= 8) + max_pixel_depth = 16; + else + max_pixel_depth = 32; + } + else if (png_ptr->color_type == PNG_COLOR_TYPE_RGB) + { + if (max_pixel_depth <= 32) + max_pixel_depth = 32; + else + max_pixel_depth = 64; + } + } +#endif + +#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED + if (png_ptr->transformations & PNG_GRAY_TO_RGB) + { + if ( +#ifdef PNG_READ_EXPAND_SUPPORTED + (png_ptr->num_trans && (png_ptr->transformations & PNG_EXPAND)) || +#endif +#ifdef PNG_READ_FILLER_SUPPORTED + (png_ptr->transformations & (PNG_FILLER)) || +#endif + png_ptr->color_type == PNG_COLOR_TYPE_GRAY_ALPHA) + { + if (max_pixel_depth <= 16) + max_pixel_depth = 32; + else + max_pixel_depth = 64; + } + else + { + if (max_pixel_depth <= 8) + { + if (png_ptr->color_type == PNG_COLOR_TYPE_RGB_ALPHA) + max_pixel_depth = 32; + else + max_pixel_depth = 24; + } + else if (png_ptr->color_type == PNG_COLOR_TYPE_RGB_ALPHA) + max_pixel_depth = 64; + else + max_pixel_depth = 48; + } + } +#endif + +#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) && \ +defined(PNG_USER_TRANSFORM_PTR_SUPPORTED) + if (png_ptr->transformations & PNG_USER_TRANSFORM) + { + int user_pixel_depth = png_ptr->user_transform_depth* + png_ptr->user_transform_channels; + if (user_pixel_depth > max_pixel_depth) + max_pixel_depth=user_pixel_depth; + } +#endif + + /* Align the width on the next larger 8 pixels. Mainly used + * for interlacing + */ + row_bytes = ((png_ptr->width + 7) & ~((png_uint_32)7)); + /* Calculate the maximum bytes needed, adding a byte and a pixel + * for safety's sake + */ + row_bytes = PNG_ROWBYTES(max_pixel_depth, row_bytes) + + 1 + ((max_pixel_depth + 7) >> 3); +#ifdef PNG_MAX_MALLOC_64K + if (row_bytes > (png_uint_32)65536L) + png_error(png_ptr, "This image requires a row greater than 64KB"); +#endif + + if (row_bytes + 48 > png_ptr->old_big_row_buf_size) + { + png_free(png_ptr, png_ptr->big_row_buf); + if (png_ptr->interlaced) + png_ptr->big_row_buf = (png_bytep)png_calloc(png_ptr, + row_bytes + 48); + else + png_ptr->big_row_buf = (png_bytep)png_malloc(png_ptr, + row_bytes + 48); + png_ptr->old_big_row_buf_size = row_bytes + 48; + +#ifdef PNG_ALIGNED_MEMORY_SUPPORTED + /* Use 16-byte aligned memory for row_buf with at least 16 bytes + * of padding before and after row_buf. + */ + png_ptr->row_buf = png_ptr->big_row_buf + 32 + - (((png_alloc_size_t)&(png_ptr->big_row_buf[0]) + 15) % 16); + png_ptr->old_big_row_buf_size = row_bytes + 48; +#else + /* Use 32 bytes of padding before and 16 bytes after row_buf. */ + png_ptr->row_buf = png_ptr->big_row_buf + 32; +#endif + png_ptr->old_big_row_buf_size = row_bytes + 48; + } + +#ifdef PNG_MAX_MALLOC_64K + if ((png_uint_32)png_ptr->rowbytes + 1 > (png_uint_32)65536L) + png_error(png_ptr, "This image requires a row greater than 64KB"); +#endif + if ((png_uint_32)png_ptr->rowbytes > (png_uint_32)(PNG_SIZE_MAX - 1)) + png_error(png_ptr, "Row has too many bytes to allocate in memory"); + + if (png_ptr->rowbytes + 1 > png_ptr->old_prev_row_size) + { + png_free(png_ptr, png_ptr->prev_row); + png_ptr->prev_row = (png_bytep)png_malloc(png_ptr, (png_uint_32)( + png_ptr->rowbytes + 1)); + png_ptr->old_prev_row_size = png_ptr->rowbytes + 1; + } + + png_memset(png_ptr->prev_row, 0, png_ptr->rowbytes + 1); + + png_debug1(3, "width = %lu,", png_ptr->width); + png_debug1(3, "height = %lu,", png_ptr->height); + png_debug1(3, "iwidth = %lu,", png_ptr->iwidth); + png_debug1(3, "num_rows = %lu,", png_ptr->num_rows); + png_debug1(3, "rowbytes = %lu,", png_ptr->rowbytes); + png_debug1(3, "irowbytes = %lu", + PNG_ROWBYTES(png_ptr->pixel_depth, png_ptr->iwidth) + 1); + + png_ptr->flags |= PNG_FLAG_ROW_INIT; +} +#endif /* PNG_READ_SUPPORTED */ diff --git a/libpng/pngset.c b/libpng/pngset.c new file mode 100644 index 0000000..1f972c4 --- /dev/null +++ b/libpng/pngset.c @@ -0,0 +1,1167 @@ + +/* pngset.c - storage of image information into info struct + * + * Last changed in libpng 1.4.1 [February 25, 2010] + * Copyright (c) 1998-2010 Glenn Randers-Pehrson + * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) + * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) + * + * This code is released under the libpng license. + * For conditions of distribution and use, see the disclaimer + * and license in png.h + * + * The functions here are used during reads to store data from the file + * into the info struct, and during writes to store application data + * into the info struct for writing into the file. This abstracts the + * info struct and allows us to change the structure in the future. + */ + +#define PNG_NO_PEDANTIC_WARNINGS +#include "png.h" +#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED) +#include "pngpriv.h" + +#ifdef PNG_bKGD_SUPPORTED +void PNGAPI +png_set_bKGD(png_structp png_ptr, png_infop info_ptr, png_color_16p background) +{ + png_debug1(1, "in %s storage function", "bKGD"); + + if (png_ptr == NULL || info_ptr == NULL) + return; + + png_memcpy(&(info_ptr->background), background, png_sizeof(png_color_16)); + info_ptr->valid |= PNG_INFO_bKGD; +} +#endif + +#ifdef PNG_cHRM_SUPPORTED +#ifdef PNG_FLOATING_POINT_SUPPORTED +void PNGAPI +png_set_cHRM(png_structp png_ptr, png_infop info_ptr, + double white_x, double white_y, double red_x, double red_y, + double green_x, double green_y, double blue_x, double blue_y) +{ + png_debug1(1, "in %s storage function", "cHRM"); + + if (png_ptr == NULL || info_ptr == NULL) + return; + + info_ptr->x_white = (float)white_x; + info_ptr->y_white = (float)white_y; + info_ptr->x_red = (float)red_x; + info_ptr->y_red = (float)red_y; + info_ptr->x_green = (float)green_x; + info_ptr->y_green = (float)green_y; + info_ptr->x_blue = (float)blue_x; + info_ptr->y_blue = (float)blue_y; +#ifdef PNG_FIXED_POINT_SUPPORTED + info_ptr->int_x_white = (png_fixed_point)(white_x*100000.+0.5); + info_ptr->int_y_white = (png_fixed_point)(white_y*100000.+0.5); + info_ptr->int_x_red = (png_fixed_point)( red_x*100000.+0.5); + info_ptr->int_y_red = (png_fixed_point)( red_y*100000.+0.5); + info_ptr->int_x_green = (png_fixed_point)(green_x*100000.+0.5); + info_ptr->int_y_green = (png_fixed_point)(green_y*100000.+0.5); + info_ptr->int_x_blue = (png_fixed_point)( blue_x*100000.+0.5); + info_ptr->int_y_blue = (png_fixed_point)( blue_y*100000.+0.5); +#endif + info_ptr->valid |= PNG_INFO_cHRM; +} +#endif /* PNG_FLOATING_POINT_SUPPORTED */ + +#ifdef PNG_FIXED_POINT_SUPPORTED +void PNGAPI +png_set_cHRM_fixed(png_structp png_ptr, png_infop info_ptr, + png_fixed_point white_x, png_fixed_point white_y, png_fixed_point red_x, + png_fixed_point red_y, png_fixed_point green_x, png_fixed_point green_y, + png_fixed_point blue_x, png_fixed_point blue_y) +{ + png_debug1(1, "in %s storage function", "cHRM fixed"); + + if (png_ptr == NULL || info_ptr == NULL) + return; + +#ifdef PNG_CHECK_cHRM_SUPPORTED + if (png_check_cHRM_fixed(png_ptr, + white_x, white_y, red_x, red_y, green_x, green_y, blue_x, blue_y)) +#endif + { + info_ptr->int_x_white = white_x; + info_ptr->int_y_white = white_y; + info_ptr->int_x_red = red_x; + info_ptr->int_y_red = red_y; + info_ptr->int_x_green = green_x; + info_ptr->int_y_green = green_y; + info_ptr->int_x_blue = blue_x; + info_ptr->int_y_blue = blue_y; +#ifdef PNG_FLOATING_POINT_SUPPORTED + info_ptr->x_white = (float)(white_x/100000.); + info_ptr->y_white = (float)(white_y/100000.); + info_ptr->x_red = (float)( red_x/100000.); + info_ptr->y_red = (float)( red_y/100000.); + info_ptr->x_green = (float)(green_x/100000.); + info_ptr->y_green = (float)(green_y/100000.); + info_ptr->x_blue = (float)( blue_x/100000.); + info_ptr->y_blue = (float)( blue_y/100000.); +#endif + info_ptr->valid |= PNG_INFO_cHRM; + } +} +#endif /* PNG_FIXED_POINT_SUPPORTED */ +#endif /* PNG_cHRM_SUPPORTED */ + +#ifdef PNG_gAMA_SUPPORTED +#ifdef PNG_FLOATING_POINT_SUPPORTED +void PNGAPI +png_set_gAMA(png_structp png_ptr, png_infop info_ptr, double file_gamma) +{ + double png_gamma; + + png_debug1(1, "in %s storage function", "gAMA"); + + if (png_ptr == NULL || info_ptr == NULL) + return; + + /* Check for overflow */ + if (file_gamma > 21474.83) + { + png_warning(png_ptr, "Limiting gamma to 21474.83"); + png_gamma=21474.83; + } + else + png_gamma = file_gamma; + info_ptr->gamma = (float)png_gamma; +#ifdef PNG_FIXED_POINT_SUPPORTED + info_ptr->int_gamma = (int)(png_gamma*100000.+.5); +#endif + info_ptr->valid |= PNG_INFO_gAMA; + if (png_gamma == 0.0) + png_warning(png_ptr, "Setting gamma=0"); +} +#endif +void PNGAPI +png_set_gAMA_fixed(png_structp png_ptr, png_infop info_ptr, png_fixed_point + int_gamma) +{ + png_fixed_point png_gamma; + + png_debug1(1, "in %s storage function", "gAMA"); + + if (png_ptr == NULL || info_ptr == NULL) + return; + + if (int_gamma > (png_fixed_point)PNG_UINT_31_MAX) + { + png_warning(png_ptr, "Limiting gamma to 21474.83"); + png_gamma=PNG_UINT_31_MAX; + } + else + { + if (int_gamma < 0) + { + png_warning(png_ptr, "Setting negative gamma to zero"); + png_gamma = 0; + } + else + png_gamma = int_gamma; + } +#ifdef PNG_FLOATING_POINT_SUPPORTED + info_ptr->gamma = (float)(png_gamma/100000.); +#endif +#ifdef PNG_FIXED_POINT_SUPPORTED + info_ptr->int_gamma = png_gamma; +#endif + info_ptr->valid |= PNG_INFO_gAMA; + if (png_gamma == 0) + png_warning(png_ptr, "Setting gamma=0"); +} +#endif + +#ifdef PNG_hIST_SUPPORTED +void PNGAPI +png_set_hIST(png_structp png_ptr, png_infop info_ptr, png_uint_16p hist) +{ + int i; + + png_debug1(1, "in %s storage function", "hIST"); + + if (png_ptr == NULL || info_ptr == NULL) + return; + + if (info_ptr->num_palette == 0 || info_ptr->num_palette + > PNG_MAX_PALETTE_LENGTH) + { + png_warning(png_ptr, + "Invalid palette size, hIST allocation skipped"); + return; + } + + png_free_data(png_ptr, info_ptr, PNG_FREE_HIST, 0); + /* Changed from info->num_palette to PNG_MAX_PALETTE_LENGTH in + * version 1.2.1 + */ + png_ptr->hist = (png_uint_16p)png_malloc_warn(png_ptr, + PNG_MAX_PALETTE_LENGTH * png_sizeof(png_uint_16)); + if (png_ptr->hist == NULL) + { + png_warning(png_ptr, "Insufficient memory for hIST chunk data"); + return; + } + + for (i = 0; i < info_ptr->num_palette; i++) + png_ptr->hist[i] = hist[i]; + info_ptr->hist = png_ptr->hist; + info_ptr->valid |= PNG_INFO_hIST; + + info_ptr->free_me |= PNG_FREE_HIST; +} +#endif + +void PNGAPI +png_set_IHDR(png_structp png_ptr, png_infop info_ptr, + png_uint_32 width, png_uint_32 height, int bit_depth, + int color_type, int interlace_type, int compression_type, + int filter_type) +{ + png_debug1(1, "in %s storage function", "IHDR"); + + if (png_ptr == NULL || info_ptr == NULL) + return; + + info_ptr->width = width; + info_ptr->height = height; + info_ptr->bit_depth = (png_byte)bit_depth; + info_ptr->color_type = (png_byte)color_type; + info_ptr->compression_type = (png_byte)compression_type; + info_ptr->filter_type = (png_byte)filter_type; + info_ptr->interlace_type = (png_byte)interlace_type; + + png_check_IHDR (png_ptr, info_ptr->width, info_ptr->height, + info_ptr->bit_depth, info_ptr->color_type, info_ptr->interlace_type, + info_ptr->compression_type, info_ptr->filter_type); + + if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE) + info_ptr->channels = 1; + else if (info_ptr->color_type & PNG_COLOR_MASK_COLOR) + info_ptr->channels = 3; + else + info_ptr->channels = 1; + if (info_ptr->color_type & PNG_COLOR_MASK_ALPHA) + info_ptr->channels++; + info_ptr->pixel_depth = (png_byte)(info_ptr->channels * info_ptr->bit_depth); + + /* Check for potential overflow */ + if (width > (PNG_UINT_32_MAX + >> 3) /* 8-byte RGBA pixels */ + - 64 /* bigrowbuf hack */ + - 1 /* filter byte */ + - 7*8 /* rounding of width to multiple of 8 pixels */ + - 8) /* extra max_pixel_depth pad */ + info_ptr->rowbytes = 0; + else + info_ptr->rowbytes = PNG_ROWBYTES(info_ptr->pixel_depth, width); +} + +#ifdef PNG_oFFs_SUPPORTED +void PNGAPI +png_set_oFFs(png_structp png_ptr, png_infop info_ptr, + png_int_32 offset_x, png_int_32 offset_y, int unit_type) +{ + png_debug1(1, "in %s storage function", "oFFs"); + + if (png_ptr == NULL || info_ptr == NULL) + return; + + info_ptr->x_offset = offset_x; + info_ptr->y_offset = offset_y; + info_ptr->offset_unit_type = (png_byte)unit_type; + info_ptr->valid |= PNG_INFO_oFFs; +} +#endif + +#ifdef PNG_pCAL_SUPPORTED +void PNGAPI +png_set_pCAL(png_structp png_ptr, png_infop info_ptr, + png_charp purpose, png_int_32 X0, png_int_32 X1, int type, int nparams, + png_charp units, png_charpp params) +{ + png_size_t length; + int i; + + png_debug1(1, "in %s storage function", "pCAL"); + + if (png_ptr == NULL || info_ptr == NULL) + return; + + length = png_strlen(purpose) + 1; + png_debug1(3, "allocating purpose for info (%lu bytes)", + (unsigned long)length); + info_ptr->pcal_purpose = (png_charp)png_malloc_warn(png_ptr, length); + if (info_ptr->pcal_purpose == NULL) + { + png_warning(png_ptr, "Insufficient memory for pCAL purpose"); + return; + } + png_memcpy(info_ptr->pcal_purpose, purpose, length); + + png_debug(3, "storing X0, X1, type, and nparams in info"); + info_ptr->pcal_X0 = X0; + info_ptr->pcal_X1 = X1; + info_ptr->pcal_type = (png_byte)type; + info_ptr->pcal_nparams = (png_byte)nparams; + + length = png_strlen(units) + 1; + png_debug1(3, "allocating units for info (%lu bytes)", + (unsigned long)length); + info_ptr->pcal_units = (png_charp)png_malloc_warn(png_ptr, length); + if (info_ptr->pcal_units == NULL) + { + png_warning(png_ptr, "Insufficient memory for pCAL units"); + return; + } + png_memcpy(info_ptr->pcal_units, units, length); + + info_ptr->pcal_params = (png_charpp)png_malloc_warn(png_ptr, + (png_size_t)((nparams + 1) * png_sizeof(png_charp))); + if (info_ptr->pcal_params == NULL) + { + png_warning(png_ptr, "Insufficient memory for pCAL params"); + return; + } + + png_memset(info_ptr->pcal_params, 0, (nparams + 1) * png_sizeof(png_charp)); + + for (i = 0; i < nparams; i++) + { + length = png_strlen(params[i]) + 1; + png_debug2(3, "allocating parameter %d for info (%lu bytes)", i, + (unsigned long)length); + info_ptr->pcal_params[i] = (png_charp)png_malloc_warn(png_ptr, length); + if (info_ptr->pcal_params[i] == NULL) + { + png_warning(png_ptr, "Insufficient memory for pCAL parameter"); + return; + } + png_memcpy(info_ptr->pcal_params[i], params[i], length); + } + + info_ptr->valid |= PNG_INFO_pCAL; + info_ptr->free_me |= PNG_FREE_PCAL; +} +#endif + +#if defined(PNG_READ_sCAL_SUPPORTED) || defined(PNG_WRITE_sCAL_SUPPORTED) +#ifdef PNG_FLOATING_POINT_SUPPORTED +void PNGAPI +png_set_sCAL(png_structp png_ptr, png_infop info_ptr, + int unit, double width, double height) +{ + png_debug1(1, "in %s storage function", "sCAL"); + + if (png_ptr == NULL || info_ptr == NULL) + return; + + info_ptr->scal_unit = (png_byte)unit; + info_ptr->scal_pixel_width = width; + info_ptr->scal_pixel_height = height; + + info_ptr->valid |= PNG_INFO_sCAL; +} +#else +#ifdef PNG_FIXED_POINT_SUPPORTED +void PNGAPI +png_set_sCAL_s(png_structp png_ptr, png_infop info_ptr, + int unit, png_charp swidth, png_charp sheight) +{ + png_size_t length; + + png_debug1(1, "in %s storage function", "sCAL"); + + if (png_ptr == NULL || info_ptr == NULL) + return; + + info_ptr->scal_unit = (png_byte)unit; + + length = png_strlen(swidth) + 1; + png_debug1(3, "allocating unit for info (%u bytes)", + (unsigned int)length); + info_ptr->scal_s_width = (png_charp)png_malloc_warn(png_ptr, length); + if (info_ptr->scal_s_width == NULL) + { + png_warning(png_ptr, + "Memory allocation failed while processing sCAL"); + return; + } + png_memcpy(info_ptr->scal_s_width, swidth, length); + + length = png_strlen(sheight) + 1; + png_debug1(3, "allocating unit for info (%u bytes)", + (unsigned int)length); + info_ptr->scal_s_height = (png_charp)png_malloc_warn(png_ptr, length); + if (info_ptr->scal_s_height == NULL) + { + png_free (png_ptr, info_ptr->scal_s_width); + info_ptr->scal_s_width = NULL; + png_warning(png_ptr, + "Memory allocation failed while processing sCAL"); + return; + } + png_memcpy(info_ptr->scal_s_height, sheight, length); + info_ptr->valid |= PNG_INFO_sCAL; + info_ptr->free_me |= PNG_FREE_SCAL; +} +#endif +#endif +#endif + +#ifdef PNG_pHYs_SUPPORTED +void PNGAPI +png_set_pHYs(png_structp png_ptr, png_infop info_ptr, + png_uint_32 res_x, png_uint_32 res_y, int unit_type) +{ + png_debug1(1, "in %s storage function", "pHYs"); + + if (png_ptr == NULL || info_ptr == NULL) + return; + + info_ptr->x_pixels_per_unit = res_x; + info_ptr->y_pixels_per_unit = res_y; + info_ptr->phys_unit_type = (png_byte)unit_type; + info_ptr->valid |= PNG_INFO_pHYs; +} +#endif + +void PNGAPI +png_set_PLTE(png_structp png_ptr, png_infop info_ptr, + png_colorp palette, int num_palette) +{ + + png_debug1(1, "in %s storage function", "PLTE"); + + if (png_ptr == NULL || info_ptr == NULL) + return; + + if (num_palette < 0 || num_palette > PNG_MAX_PALETTE_LENGTH) + { + if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE) + png_error(png_ptr, "Invalid palette length"); + else + { + png_warning(png_ptr, "Invalid palette length"); + return; + } + } + + /* It may not actually be necessary to set png_ptr->palette here; + * we do it for backward compatibility with the way the png_handle_tRNS + * function used to do the allocation. + */ + png_free_data(png_ptr, info_ptr, PNG_FREE_PLTE, 0); + + /* Changed in libpng-1.2.1 to allocate PNG_MAX_PALETTE_LENGTH instead + * of num_palette entries, in case of an invalid PNG file that has + * too-large sample values. + */ + png_ptr->palette = (png_colorp)png_calloc(png_ptr, + PNG_MAX_PALETTE_LENGTH * png_sizeof(png_color)); + png_memcpy(png_ptr->palette, palette, num_palette * png_sizeof(png_color)); + info_ptr->palette = png_ptr->palette; + info_ptr->num_palette = png_ptr->num_palette = (png_uint_16)num_palette; + + info_ptr->free_me |= PNG_FREE_PLTE; + + info_ptr->valid |= PNG_INFO_PLTE; +} + +#ifdef PNG_sBIT_SUPPORTED +void PNGAPI +png_set_sBIT(png_structp png_ptr, png_infop info_ptr, + png_color_8p sig_bit) +{ + png_debug1(1, "in %s storage function", "sBIT"); + + if (png_ptr == NULL || info_ptr == NULL) + return; + + png_memcpy(&(info_ptr->sig_bit), sig_bit, png_sizeof(png_color_8)); + info_ptr->valid |= PNG_INFO_sBIT; +} +#endif + +#ifdef PNG_sRGB_SUPPORTED +void PNGAPI +png_set_sRGB(png_structp png_ptr, png_infop info_ptr, int intent) +{ + png_debug1(1, "in %s storage function", "sRGB"); + + if (png_ptr == NULL || info_ptr == NULL) + return; + + info_ptr->srgb_intent = (png_byte)intent; + info_ptr->valid |= PNG_INFO_sRGB; +} + +void PNGAPI +png_set_sRGB_gAMA_and_cHRM(png_structp png_ptr, png_infop info_ptr, + int intent) +{ +#ifdef PNG_gAMA_SUPPORTED +#ifdef PNG_FLOATING_POINT_SUPPORTED + float file_gamma; +#endif +#ifdef PNG_FIXED_POINT_SUPPORTED + png_fixed_point int_file_gamma; +#endif +#endif +#ifdef PNG_cHRM_SUPPORTED +#ifdef PNG_FLOATING_POINT_SUPPORTED + float white_x, white_y, red_x, red_y, green_x, green_y, blue_x, blue_y; +#endif + png_fixed_point int_white_x, int_white_y, int_red_x, int_red_y, int_green_x, + int_green_y, int_blue_x, int_blue_y; +#endif + png_debug1(1, "in %s storage function", "sRGB_gAMA_and_cHRM"); + + if (png_ptr == NULL || info_ptr == NULL) + return; + + png_set_sRGB(png_ptr, info_ptr, intent); + +#ifdef PNG_gAMA_SUPPORTED +#ifdef PNG_FLOATING_POINT_SUPPORTED + file_gamma = (float).45455; + png_set_gAMA(png_ptr, info_ptr, file_gamma); +#endif +#ifdef PNG_FIXED_POINT_SUPPORTED + int_file_gamma = 45455L; + png_set_gAMA_fixed(png_ptr, info_ptr, int_file_gamma); +#endif +#endif + +#ifdef PNG_cHRM_SUPPORTED + int_white_x = 31270L; + int_white_y = 32900L; + int_red_x = 64000L; + int_red_y = 33000L; + int_green_x = 30000L; + int_green_y = 60000L; + int_blue_x = 15000L; + int_blue_y = 6000L; + +#ifdef PNG_FLOATING_POINT_SUPPORTED + white_x = (float).3127; + white_y = (float).3290; + red_x = (float).64; + red_y = (float).33; + green_x = (float).30; + green_y = (float).60; + blue_x = (float).15; + blue_y = (float).06; +#endif + +#ifdef PNG_FIXED_POINT_SUPPORTED + png_set_cHRM_fixed(png_ptr, info_ptr, + int_white_x, int_white_y, int_red_x, int_red_y, int_green_x, + int_green_y, int_blue_x, int_blue_y); +#endif +#ifdef PNG_FLOATING_POINT_SUPPORTED + png_set_cHRM(png_ptr, info_ptr, + white_x, white_y, red_x, red_y, green_x, green_y, blue_x, blue_y); +#endif +#endif /* cHRM */ +} +#endif /* sRGB */ + + +#ifdef PNG_iCCP_SUPPORTED +void PNGAPI +png_set_iCCP(png_structp png_ptr, png_infop info_ptr, + png_charp name, int compression_type, + png_charp profile, png_uint_32 proflen) +{ + png_charp new_iccp_name; + png_charp new_iccp_profile; + png_uint_32 length; + + png_debug1(1, "in %s storage function", "iCCP"); + + if (png_ptr == NULL || info_ptr == NULL || name == NULL || profile == NULL) + return; + + length = png_strlen(name)+1; + new_iccp_name = (png_charp)png_malloc_warn(png_ptr, length); + if (new_iccp_name == NULL) + { + png_warning(png_ptr, "Insufficient memory to process iCCP chunk"); + return; + } + png_memcpy(new_iccp_name, name, length); + new_iccp_profile = (png_charp)png_malloc_warn(png_ptr, proflen); + if (new_iccp_profile == NULL) + { + png_free (png_ptr, new_iccp_name); + png_warning(png_ptr, + "Insufficient memory to process iCCP profile"); + return; + } + png_memcpy(new_iccp_profile, profile, (png_size_t)proflen); + + png_free_data(png_ptr, info_ptr, PNG_FREE_ICCP, 0); + + info_ptr->iccp_proflen = proflen; + info_ptr->iccp_name = new_iccp_name; + info_ptr->iccp_profile = new_iccp_profile; + /* Compression is always zero but is here so the API and info structure + * does not have to change if we introduce multiple compression types + */ + info_ptr->iccp_compression = (png_byte)compression_type; + info_ptr->free_me |= PNG_FREE_ICCP; + info_ptr->valid |= PNG_INFO_iCCP; +} +#endif + +#ifdef PNG_TEXT_SUPPORTED +void PNGAPI +png_set_text(png_structp png_ptr, png_infop info_ptr, png_textp text_ptr, + int num_text) +{ + int ret; + ret = png_set_text_2(png_ptr, info_ptr, text_ptr, num_text); + if (ret) + png_error(png_ptr, "Insufficient memory to store text"); +} + +int /* PRIVATE */ +png_set_text_2(png_structp png_ptr, png_infop info_ptr, png_textp text_ptr, + int num_text) +{ + int i; + + png_debug1(1, "in %s storage function", ((png_ptr == NULL || + png_ptr->chunk_name[0] == '\0') ? + "text" : (png_const_charp)png_ptr->chunk_name)); + + if (png_ptr == NULL || info_ptr == NULL || num_text == 0) + return(0); + + /* Make sure we have enough space in the "text" array in info_struct + * to hold all of the incoming text_ptr objects. + */ + if (info_ptr->num_text + num_text > info_ptr->max_text) + { + if (info_ptr->text != NULL) + { + png_textp old_text; + int old_max; + + old_max = info_ptr->max_text; + info_ptr->max_text = info_ptr->num_text + num_text + 8; + old_text = info_ptr->text; + info_ptr->text = (png_textp)png_malloc_warn(png_ptr, + (png_size_t)(info_ptr->max_text * png_sizeof(png_text))); + if (info_ptr->text == NULL) + { + png_free(png_ptr, old_text); + return(1); + } + png_memcpy(info_ptr->text, old_text, (png_size_t)(old_max * + png_sizeof(png_text))); + png_free(png_ptr, old_text); + } + else + { + info_ptr->max_text = num_text + 8; + info_ptr->num_text = 0; + info_ptr->text = (png_textp)png_malloc_warn(png_ptr, + (png_size_t)(info_ptr->max_text * png_sizeof(png_text))); + if (info_ptr->text == NULL) + return(1); + info_ptr->free_me |= PNG_FREE_TEXT; + } + png_debug1(3, "allocated %d entries for info_ptr->text", + info_ptr->max_text); + } + for (i = 0; i < num_text; i++) + { + png_size_t text_length, key_len; + png_size_t lang_len, lang_key_len; + png_textp textp = &(info_ptr->text[info_ptr->num_text]); + + if (text_ptr[i].key == NULL) + continue; + + key_len = png_strlen(text_ptr[i].key); + + if (text_ptr[i].compression <= 0) + { + lang_len = 0; + lang_key_len = 0; + } + + else +#ifdef PNG_iTXt_SUPPORTED + { + /* Set iTXt data */ + + if (text_ptr[i].lang != NULL) + lang_len = png_strlen(text_ptr[i].lang); + else + lang_len = 0; + if (text_ptr[i].lang_key != NULL) + lang_key_len = png_strlen(text_ptr[i].lang_key); + else + lang_key_len = 0; + } +#else /* PNG_iTXt_SUPPORTED */ + { + png_warning(png_ptr, "iTXt chunk not supported"); + continue; + } +#endif + + if (text_ptr[i].text == NULL || text_ptr[i].text[0] == '\0') + { + text_length = 0; +#ifdef PNG_iTXt_SUPPORTED + if (text_ptr[i].compression > 0) + textp->compression = PNG_ITXT_COMPRESSION_NONE; + else +#endif + textp->compression = PNG_TEXT_COMPRESSION_NONE; + } + + else + { + text_length = png_strlen(text_ptr[i].text); + textp->compression = text_ptr[i].compression; + } + + textp->key = (png_charp)png_malloc_warn(png_ptr, + (png_size_t) + (key_len + text_length + lang_len + lang_key_len + 4)); + if (textp->key == NULL) + return(1); + png_debug2(2, "Allocated %lu bytes at %x in png_set_text", + (unsigned long)(png_uint_32) + (key_len + lang_len + lang_key_len + text_length + 4), + (int)textp->key); + + png_memcpy(textp->key, text_ptr[i].key,(png_size_t)(key_len)); + *(textp->key + key_len) = '\0'; +#ifdef PNG_iTXt_SUPPORTED + if (text_ptr[i].compression > 0) + { + textp->lang = textp->key + key_len + 1; + png_memcpy(textp->lang, text_ptr[i].lang, lang_len); + *(textp->lang + lang_len) = '\0'; + textp->lang_key = textp->lang + lang_len + 1; + png_memcpy(textp->lang_key, text_ptr[i].lang_key, lang_key_len); + *(textp->lang_key + lang_key_len) = '\0'; + textp->text = textp->lang_key + lang_key_len + 1; + } + else +#endif + { +#ifdef PNG_iTXt_SUPPORTED + textp->lang=NULL; + textp->lang_key=NULL; +#endif + textp->text = textp->key + key_len + 1; + } + if (text_length) + png_memcpy(textp->text, text_ptr[i].text, + (png_size_t)(text_length)); + *(textp->text + text_length) = '\0'; + +#ifdef PNG_iTXt_SUPPORTED + if (textp->compression > 0) + { + textp->text_length = 0; + textp->itxt_length = text_length; + } + else +#endif + + { + textp->text_length = text_length; +#ifdef PNG_iTXt_SUPPORTED + textp->itxt_length = 0; +#endif + } + info_ptr->num_text++; + png_debug1(3, "transferred text chunk %d", info_ptr->num_text); + } + return(0); +} +#endif + +#ifdef PNG_tIME_SUPPORTED +void PNGAPI +png_set_tIME(png_structp png_ptr, png_infop info_ptr, png_timep mod_time) +{ + png_debug1(1, "in %s storage function", "tIME"); + + if (png_ptr == NULL || info_ptr == NULL || + (png_ptr->mode & PNG_WROTE_tIME)) + return; + + png_memcpy(&(info_ptr->mod_time), mod_time, png_sizeof(png_time)); + info_ptr->valid |= PNG_INFO_tIME; +} +#endif + +#ifdef PNG_tRNS_SUPPORTED +void PNGAPI +png_set_tRNS(png_structp png_ptr, png_infop info_ptr, + png_bytep trans_alpha, int num_trans, png_color_16p trans_color) +{ + png_debug1(1, "in %s storage function", "tRNS"); + + if (png_ptr == NULL || info_ptr == NULL) + return; + + if (trans_alpha != NULL) + { + /* It may not actually be necessary to set png_ptr->trans_alpha here; + * we do it for backward compatibility with the way the png_handle_tRNS + * function used to do the allocation. + */ + + png_free_data(png_ptr, info_ptr, PNG_FREE_TRNS, 0); + + /* Changed from num_trans to PNG_MAX_PALETTE_LENGTH in version 1.2.1 */ + png_ptr->trans_alpha = info_ptr->trans_alpha = (png_bytep)png_malloc(png_ptr, + (png_size_t)PNG_MAX_PALETTE_LENGTH); + if (num_trans > 0 && num_trans <= PNG_MAX_PALETTE_LENGTH) + png_memcpy(info_ptr->trans_alpha, trans_alpha, (png_size_t)num_trans); + } + + if (trans_color != NULL) + { + int sample_max = (1 << info_ptr->bit_depth); + if ((info_ptr->color_type == PNG_COLOR_TYPE_GRAY && + (int)trans_color->gray > sample_max) || + (info_ptr->color_type == PNG_COLOR_TYPE_RGB && + ((int)trans_color->red > sample_max || + (int)trans_color->green > sample_max || + (int)trans_color->blue > sample_max))) + png_warning(png_ptr, + "tRNS chunk has out-of-range samples for bit_depth"); + png_memcpy(&(info_ptr->trans_color), trans_color, + png_sizeof(png_color_16)); + if (num_trans == 0) + num_trans = 1; + } + + info_ptr->num_trans = (png_uint_16)num_trans; + if (num_trans != 0) + { + info_ptr->valid |= PNG_INFO_tRNS; + info_ptr->free_me |= PNG_FREE_TRNS; + } +} +#endif + +#ifdef PNG_sPLT_SUPPORTED +void PNGAPI +png_set_sPLT(png_structp png_ptr, + png_infop info_ptr, png_sPLT_tp entries, int nentries) +/* + * entries - array of png_sPLT_t structures + * to be added to the list of palettes + * in the info structure. + * nentries - number of palette structures to be + * added. + */ +{ + png_sPLT_tp np; + int i; + + if (png_ptr == NULL || info_ptr == NULL) + return; + + np = (png_sPLT_tp)png_malloc_warn(png_ptr, + (info_ptr->splt_palettes_num + nentries) * + (png_size_t)png_sizeof(png_sPLT_t)); + if (np == NULL) + { + png_warning(png_ptr, "No memory for sPLT palettes"); + return; + } + + png_memcpy(np, info_ptr->splt_palettes, + info_ptr->splt_palettes_num * png_sizeof(png_sPLT_t)); + png_free(png_ptr, info_ptr->splt_palettes); + info_ptr->splt_palettes=NULL; + + for (i = 0; i < nentries; i++) + { + png_sPLT_tp to = np + info_ptr->splt_palettes_num + i; + png_sPLT_tp from = entries + i; + png_uint_32 length; + + length = png_strlen(from->name) + 1; + to->name = (png_charp)png_malloc_warn(png_ptr, (png_size_t)length); + if (to->name == NULL) + { + png_warning(png_ptr, + "Out of memory while processing sPLT chunk"); + continue; + } + png_memcpy(to->name, from->name, length); + to->entries = (png_sPLT_entryp)png_malloc_warn(png_ptr, + (png_size_t)(from->nentries * png_sizeof(png_sPLT_entry))); + if (to->entries == NULL) + { + png_warning(png_ptr, + "Out of memory while processing sPLT chunk"); + png_free(png_ptr, to->name); + to->name = NULL; + continue; + } + png_memcpy(to->entries, from->entries, + from->nentries * png_sizeof(png_sPLT_entry)); + to->nentries = from->nentries; + to->depth = from->depth; + } + + info_ptr->splt_palettes = np; + info_ptr->splt_palettes_num += nentries; + info_ptr->valid |= PNG_INFO_sPLT; + info_ptr->free_me |= PNG_FREE_SPLT; +} +#endif /* PNG_sPLT_SUPPORTED */ + +#ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED +void PNGAPI +png_set_unknown_chunks(png_structp png_ptr, + png_infop info_ptr, png_unknown_chunkp unknowns, int num_unknowns) +{ + png_unknown_chunkp np; + int i; + + if (png_ptr == NULL || info_ptr == NULL || num_unknowns == 0) + return; + + np = (png_unknown_chunkp)png_malloc_warn(png_ptr, + (png_size_t)((info_ptr->unknown_chunks_num + num_unknowns) * + png_sizeof(png_unknown_chunk))); + if (np == NULL) + { + png_warning(png_ptr, + "Out of memory while processing unknown chunk"); + return; + } + + png_memcpy(np, info_ptr->unknown_chunks, + info_ptr->unknown_chunks_num * png_sizeof(png_unknown_chunk)); + png_free(png_ptr, info_ptr->unknown_chunks); + info_ptr->unknown_chunks = NULL; + + for (i = 0; i < num_unknowns; i++) + { + png_unknown_chunkp to = np + info_ptr->unknown_chunks_num + i; + png_unknown_chunkp from = unknowns + i; + + png_memcpy((png_charp)to->name, (png_charp)from->name, + png_sizeof(from->name)); + to->name[png_sizeof(to->name)-1] = '\0'; + to->size = from->size; + /* Note our location in the read or write sequence */ + to->location = (png_byte)(png_ptr->mode & 0xff); + + if (from->size == 0) + to->data=NULL; + else + { + to->data = (png_bytep)png_malloc_warn(png_ptr, + (png_size_t)from->size); + if (to->data == NULL) + { + png_warning(png_ptr, + "Out of memory while processing unknown chunk"); + to->size = 0; + } + else + png_memcpy(to->data, from->data, from->size); + } + } + + info_ptr->unknown_chunks = np; + info_ptr->unknown_chunks_num += num_unknowns; + info_ptr->free_me |= PNG_FREE_UNKN; +} +void PNGAPI +png_set_unknown_chunk_location(png_structp png_ptr, png_infop info_ptr, + int chunk, int location) +{ + if (png_ptr != NULL && info_ptr != NULL && chunk >= 0 && chunk < + (int)info_ptr->unknown_chunks_num) + info_ptr->unknown_chunks[chunk].location = (png_byte)location; +} +#endif + + +#ifdef PNG_MNG_FEATURES_SUPPORTED +png_uint_32 PNGAPI +png_permit_mng_features (png_structp png_ptr, png_uint_32 mng_features) +{ + png_debug(1, "in png_permit_mng_features"); + + if (png_ptr == NULL) + return (png_uint_32)0; + png_ptr->mng_features_permitted = + (png_byte)(mng_features & PNG_ALL_MNG_FEATURES); + return (png_uint_32)png_ptr->mng_features_permitted; +} +#endif + +#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED +void PNGAPI +png_set_keep_unknown_chunks(png_structp png_ptr, int keep, png_bytep + chunk_list, int num_chunks) +{ + png_bytep new_list, p; + int i, old_num_chunks; + if (png_ptr == NULL) + return; + if (num_chunks == 0) + { + if (keep == PNG_HANDLE_CHUNK_ALWAYS || keep == PNG_HANDLE_CHUNK_IF_SAFE) + png_ptr->flags |= PNG_FLAG_KEEP_UNKNOWN_CHUNKS; + else + png_ptr->flags &= ~PNG_FLAG_KEEP_UNKNOWN_CHUNKS; + + if (keep == PNG_HANDLE_CHUNK_ALWAYS) + png_ptr->flags |= PNG_FLAG_KEEP_UNSAFE_CHUNKS; + else + png_ptr->flags &= ~PNG_FLAG_KEEP_UNSAFE_CHUNKS; + return; + } + if (chunk_list == NULL) + return; + old_num_chunks = png_ptr->num_chunk_list; + new_list=(png_bytep)png_malloc(png_ptr, + (png_size_t) + (5*(num_chunks + old_num_chunks))); + if (png_ptr->chunk_list != NULL) + { + png_memcpy(new_list, png_ptr->chunk_list, + (png_size_t)(5*old_num_chunks)); + png_free(png_ptr, png_ptr->chunk_list); + png_ptr->chunk_list=NULL; + } + png_memcpy(new_list + 5*old_num_chunks, chunk_list, + (png_size_t)(5*num_chunks)); + for (p = new_list + 5*old_num_chunks + 4, i = 0; inum_chunk_list = old_num_chunks + num_chunks; + png_ptr->chunk_list = new_list; + png_ptr->free_me |= PNG_FREE_LIST; +} +#endif + +#ifdef PNG_READ_USER_CHUNKS_SUPPORTED +void PNGAPI +png_set_read_user_chunk_fn(png_structp png_ptr, png_voidp user_chunk_ptr, + png_user_chunk_ptr read_user_chunk_fn) +{ + png_debug(1, "in png_set_read_user_chunk_fn"); + + if (png_ptr == NULL) + return; + + png_ptr->read_user_chunk_fn = read_user_chunk_fn; + png_ptr->user_chunk_ptr = user_chunk_ptr; +} +#endif + +#ifdef PNG_INFO_IMAGE_SUPPORTED +void PNGAPI +png_set_rows(png_structp png_ptr, png_infop info_ptr, png_bytepp row_pointers) +{ + png_debug1(1, "in %s storage function", "rows"); + + if (png_ptr == NULL || info_ptr == NULL) + return; + + if (info_ptr->row_pointers && (info_ptr->row_pointers != row_pointers)) + png_free_data(png_ptr, info_ptr, PNG_FREE_ROWS, 0); + info_ptr->row_pointers = row_pointers; + if (row_pointers) + info_ptr->valid |= PNG_INFO_IDAT; +} +#endif + +void PNGAPI +png_set_compression_buffer_size(png_structp png_ptr, + png_size_t size) +{ + if (png_ptr == NULL) + return; + png_free(png_ptr, png_ptr->zbuf); + png_ptr->zbuf_size = size; + png_ptr->zbuf = (png_bytep)png_malloc(png_ptr, size); + png_ptr->zstream.next_out = png_ptr->zbuf; + png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size; +} + +void PNGAPI +png_set_invalid(png_structp png_ptr, png_infop info_ptr, int mask) +{ + if (png_ptr && info_ptr) + info_ptr->valid &= ~mask; +} + + + +#ifdef PNG_SET_USER_LIMITS_SUPPORTED +/* This function was added to libpng 1.2.6 */ +void PNGAPI +png_set_user_limits (png_structp png_ptr, png_uint_32 user_width_max, + png_uint_32 user_height_max) +{ + /* Images with dimensions larger than these limits will be + * rejected by png_set_IHDR(). To accept any PNG datastream + * regardless of dimensions, set both limits to 0x7ffffffL. + */ + if (png_ptr == NULL) + return; + png_ptr->user_width_max = user_width_max; + png_ptr->user_height_max = user_height_max; +} + +/* This function was added to libpng 1.4.0 */ +void PNGAPI +png_set_chunk_cache_max (png_structp png_ptr, + png_uint_32 user_chunk_cache_max) +{ + if (png_ptr) + png_ptr->user_chunk_cache_max = user_chunk_cache_max; +} + +/* This function was added to libpng 1.4.1 */ +void PNGAPI +png_set_chunk_malloc_max (png_structp png_ptr, + png_alloc_size_t user_chunk_malloc_max) +{ + if (png_ptr) + png_ptr->user_chunk_malloc_max = + (png_size_t)user_chunk_malloc_max; +} +#endif /* ?PNG_SET_USER_LIMITS_SUPPORTED */ + + +#ifdef PNG_BENIGN_ERRORS_SUPPORTED +void PNGAPI +png_set_benign_errors(png_structp png_ptr, int allowed) +{ + png_debug(1, "in png_set_benign_errors"); + + if (allowed) + png_ptr->flags |= PNG_FLAG_BENIGN_ERRORS_WARN; + else + png_ptr->flags &= ~PNG_FLAG_BENIGN_ERRORS_WARN; +} +#endif /* PNG_BENIGN_ERRORS_SUPPORTED */ +#endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */ diff --git a/libpng/pngtrans.c b/libpng/pngtrans.c new file mode 100644 index 0000000..741daf4 --- /dev/null +++ b/libpng/pngtrans.c @@ -0,0 +1,677 @@ + +/* pngtrans.c - transforms the data in a row (used by both readers and writers) + * + * Last changed in libpng 1.4.2 [April 29, 2010] + * Copyright (c) 1998-2010 Glenn Randers-Pehrson + * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) + * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) + * + * This code is released under the libpng license. + * For conditions of distribution and use, see the disclaimer + * and license in png.h + */ + +#define PNG_NO_PEDANTIC_WARNINGS +#include "png.h" +#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED) +#include "pngpriv.h" + +#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED) +/* Turn on BGR-to-RGB mapping */ +void PNGAPI +png_set_bgr(png_structp png_ptr) +{ + png_debug(1, "in png_set_bgr"); + + if (png_ptr == NULL) + return; + png_ptr->transformations |= PNG_BGR; +} +#endif + +#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED) +/* Turn on 16 bit byte swapping */ +void PNGAPI +png_set_swap(png_structp png_ptr) +{ + png_debug(1, "in png_set_swap"); + + if (png_ptr == NULL) + return; + if (png_ptr->bit_depth == 16) + png_ptr->transformations |= PNG_SWAP_BYTES; +} +#endif + +#if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED) +/* Turn on pixel packing */ +void PNGAPI +png_set_packing(png_structp png_ptr) +{ + png_debug(1, "in png_set_packing"); + + if (png_ptr == NULL) + return; + if (png_ptr->bit_depth < 8) + { + png_ptr->transformations |= PNG_PACK; + png_ptr->usr_bit_depth = 8; + } +} +#endif + +#if defined(PNG_READ_PACKSWAP_SUPPORTED)||defined(PNG_WRITE_PACKSWAP_SUPPORTED) +/* Turn on packed pixel swapping */ +void PNGAPI +png_set_packswap(png_structp png_ptr) +{ + png_debug(1, "in png_set_packswap"); + + if (png_ptr == NULL) + return; + if (png_ptr->bit_depth < 8) + png_ptr->transformations |= PNG_PACKSWAP; +} +#endif + +#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED) +void PNGAPI +png_set_shift(png_structp png_ptr, png_color_8p true_bits) +{ + png_debug(1, "in png_set_shift"); + + if (png_ptr == NULL) + return; + png_ptr->transformations |= PNG_SHIFT; + png_ptr->shift = *true_bits; +} +#endif + +#if defined(PNG_READ_INTERLACING_SUPPORTED) || \ + defined(PNG_WRITE_INTERLACING_SUPPORTED) +int PNGAPI +png_set_interlace_handling(png_structp png_ptr) +{ + png_debug(1, "in png_set_interlace handling"); + + if (png_ptr && png_ptr->interlaced) + { + png_ptr->transformations |= PNG_INTERLACE; + return (7); + } + + return (1); +} +#endif + +#if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED) +/* Add a filler byte on read, or remove a filler or alpha byte on write. + * The filler type has changed in v0.95 to allow future 2-byte fillers + * for 48-bit input data, as well as to avoid problems with some compilers + * that don't like bytes as parameters. + */ +void PNGAPI +png_set_filler(png_structp png_ptr, png_uint_32 filler, int filler_loc) +{ + png_debug(1, "in png_set_filler"); + + if (png_ptr == NULL) + return; + png_ptr->transformations |= PNG_FILLER; + png_ptr->filler = (png_uint_16)filler; + if (filler_loc == PNG_FILLER_AFTER) + png_ptr->flags |= PNG_FLAG_FILLER_AFTER; + else + png_ptr->flags &= ~PNG_FLAG_FILLER_AFTER; + + /* This should probably go in the "do_read_filler" routine. + * I attempted to do that in libpng-1.0.1a but that caused problems + * so I restored it in libpng-1.0.2a + */ + + if (png_ptr->color_type == PNG_COLOR_TYPE_RGB) + { + png_ptr->usr_channels = 4; + } + + /* Also I added this in libpng-1.0.2a (what happens when we expand + * a less-than-8-bit grayscale to GA? */ + + if (png_ptr->color_type == PNG_COLOR_TYPE_GRAY && png_ptr->bit_depth >= 8) + { + png_ptr->usr_channels = 2; + } +} + +/* Added to libpng-1.2.7 */ +void PNGAPI +png_set_add_alpha(png_structp png_ptr, png_uint_32 filler, int filler_loc) +{ + png_debug(1, "in png_set_add_alpha"); + + if (png_ptr == NULL) + return; + png_set_filler(png_ptr, filler, filler_loc); + png_ptr->transformations |= PNG_ADD_ALPHA; +} + +#endif + +#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) || \ + defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED) +void PNGAPI +png_set_swap_alpha(png_structp png_ptr) +{ + png_debug(1, "in png_set_swap_alpha"); + + if (png_ptr == NULL) + return; + png_ptr->transformations |= PNG_SWAP_ALPHA; +} +#endif + +#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) || \ + defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED) +void PNGAPI +png_set_invert_alpha(png_structp png_ptr) +{ + png_debug(1, "in png_set_invert_alpha"); + + if (png_ptr == NULL) + return; + png_ptr->transformations |= PNG_INVERT_ALPHA; +} +#endif + +#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED) +void PNGAPI +png_set_invert_mono(png_structp png_ptr) +{ + png_debug(1, "in png_set_invert_mono"); + + if (png_ptr == NULL) + return; + png_ptr->transformations |= PNG_INVERT_MONO; +} + +/* Invert monochrome grayscale data */ +void /* PRIVATE */ +png_do_invert(png_row_infop row_info, png_bytep row) +{ + png_debug(1, "in png_do_invert"); + + /* This test removed from libpng version 1.0.13 and 1.2.0: + * if (row_info->bit_depth == 1 && + */ + if (row_info->color_type == PNG_COLOR_TYPE_GRAY) + { + png_bytep rp = row; + png_uint_32 i; + png_uint_32 istop = row_info->rowbytes; + + for (i = 0; i < istop; i++) + { + *rp = (png_byte)(~(*rp)); + rp++; + } + } + else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA && + row_info->bit_depth == 8) + { + png_bytep rp = row; + png_uint_32 i; + png_uint_32 istop = row_info->rowbytes; + + for (i = 0; i < istop; i+=2) + { + *rp = (png_byte)(~(*rp)); + rp+=2; + } + } + else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA && + row_info->bit_depth == 16) + { + png_bytep rp = row; + png_uint_32 i; + png_uint_32 istop = row_info->rowbytes; + + for (i = 0; i < istop; i+=4) + { + *rp = (png_byte)(~(*rp)); + *(rp+1) = (png_byte)(~(*(rp+1))); + rp+=4; + } + } +} +#endif + +#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED) +/* Swaps byte order on 16 bit depth images */ +void /* PRIVATE */ +png_do_swap(png_row_infop row_info, png_bytep row) +{ + png_debug(1, "in png_do_swap"); + + if ( + row_info->bit_depth == 16) + { + png_bytep rp = row; + png_uint_32 i; + png_uint_32 istop= row_info->width * row_info->channels; + + for (i = 0; i < istop; i++, rp += 2) + { + png_byte t = *rp; + *rp = *(rp + 1); + *(rp + 1) = t; + } + } +} +#endif + +#if defined(PNG_READ_PACKSWAP_SUPPORTED)||defined(PNG_WRITE_PACKSWAP_SUPPORTED) +static PNG_CONST png_byte onebppswaptable[256] = { + 0x00, 0x80, 0x40, 0xC0, 0x20, 0xA0, 0x60, 0xE0, + 0x10, 0x90, 0x50, 0xD0, 0x30, 0xB0, 0x70, 0xF0, + 0x08, 0x88, 0x48, 0xC8, 0x28, 0xA8, 0x68, 0xE8, + 0x18, 0x98, 0x58, 0xD8, 0x38, 0xB8, 0x78, 0xF8, + 0x04, 0x84, 0x44, 0xC4, 0x24, 0xA4, 0x64, 0xE4, + 0x14, 0x94, 0x54, 0xD4, 0x34, 0xB4, 0x74, 0xF4, + 0x0C, 0x8C, 0x4C, 0xCC, 0x2C, 0xAC, 0x6C, 0xEC, + 0x1C, 0x9C, 0x5C, 0xDC, 0x3C, 0xBC, 0x7C, 0xFC, + 0x02, 0x82, 0x42, 0xC2, 0x22, 0xA2, 0x62, 0xE2, + 0x12, 0x92, 0x52, 0xD2, 0x32, 0xB2, 0x72, 0xF2, + 0x0A, 0x8A, 0x4A, 0xCA, 0x2A, 0xAA, 0x6A, 0xEA, + 0x1A, 0x9A, 0x5A, 0xDA, 0x3A, 0xBA, 0x7A, 0xFA, + 0x06, 0x86, 0x46, 0xC6, 0x26, 0xA6, 0x66, 0xE6, + 0x16, 0x96, 0x56, 0xD6, 0x36, 0xB6, 0x76, 0xF6, + 0x0E, 0x8E, 0x4E, 0xCE, 0x2E, 0xAE, 0x6E, 0xEE, + 0x1E, 0x9E, 0x5E, 0xDE, 0x3E, 0xBE, 0x7E, 0xFE, + 0x01, 0x81, 0x41, 0xC1, 0x21, 0xA1, 0x61, 0xE1, + 0x11, 0x91, 0x51, 0xD1, 0x31, 0xB1, 0x71, 0xF1, + 0x09, 0x89, 0x49, 0xC9, 0x29, 0xA9, 0x69, 0xE9, + 0x19, 0x99, 0x59, 0xD9, 0x39, 0xB9, 0x79, 0xF9, + 0x05, 0x85, 0x45, 0xC5, 0x25, 0xA5, 0x65, 0xE5, + 0x15, 0x95, 0x55, 0xD5, 0x35, 0xB5, 0x75, 0xF5, + 0x0D, 0x8D, 0x4D, 0xCD, 0x2D, 0xAD, 0x6D, 0xED, + 0x1D, 0x9D, 0x5D, 0xDD, 0x3D, 0xBD, 0x7D, 0xFD, + 0x03, 0x83, 0x43, 0xC3, 0x23, 0xA3, 0x63, 0xE3, + 0x13, 0x93, 0x53, 0xD3, 0x33, 0xB3, 0x73, 0xF3, + 0x0B, 0x8B, 0x4B, 0xCB, 0x2B, 0xAB, 0x6B, 0xEB, + 0x1B, 0x9B, 0x5B, 0xDB, 0x3B, 0xBB, 0x7B, 0xFB, + 0x07, 0x87, 0x47, 0xC7, 0x27, 0xA7, 0x67, 0xE7, + 0x17, 0x97, 0x57, 0xD7, 0x37, 0xB7, 0x77, 0xF7, + 0x0F, 0x8F, 0x4F, 0xCF, 0x2F, 0xAF, 0x6F, 0xEF, + 0x1F, 0x9F, 0x5F, 0xDF, 0x3F, 0xBF, 0x7F, 0xFF +}; + +static PNG_CONST png_byte twobppswaptable[256] = { + 0x00, 0x40, 0x80, 0xC0, 0x10, 0x50, 0x90, 0xD0, + 0x20, 0x60, 0xA0, 0xE0, 0x30, 0x70, 0xB0, 0xF0, + 0x04, 0x44, 0x84, 0xC4, 0x14, 0x54, 0x94, 0xD4, + 0x24, 0x64, 0xA4, 0xE4, 0x34, 0x74, 0xB4, 0xF4, + 0x08, 0x48, 0x88, 0xC8, 0x18, 0x58, 0x98, 0xD8, + 0x28, 0x68, 0xA8, 0xE8, 0x38, 0x78, 0xB8, 0xF8, + 0x0C, 0x4C, 0x8C, 0xCC, 0x1C, 0x5C, 0x9C, 0xDC, + 0x2C, 0x6C, 0xAC, 0xEC, 0x3C, 0x7C, 0xBC, 0xFC, + 0x01, 0x41, 0x81, 0xC1, 0x11, 0x51, 0x91, 0xD1, + 0x21, 0x61, 0xA1, 0xE1, 0x31, 0x71, 0xB1, 0xF1, + 0x05, 0x45, 0x85, 0xC5, 0x15, 0x55, 0x95, 0xD5, + 0x25, 0x65, 0xA5, 0xE5, 0x35, 0x75, 0xB5, 0xF5, + 0x09, 0x49, 0x89, 0xC9, 0x19, 0x59, 0x99, 0xD9, + 0x29, 0x69, 0xA9, 0xE9, 0x39, 0x79, 0xB9, 0xF9, + 0x0D, 0x4D, 0x8D, 0xCD, 0x1D, 0x5D, 0x9D, 0xDD, + 0x2D, 0x6D, 0xAD, 0xED, 0x3D, 0x7D, 0xBD, 0xFD, + 0x02, 0x42, 0x82, 0xC2, 0x12, 0x52, 0x92, 0xD2, + 0x22, 0x62, 0xA2, 0xE2, 0x32, 0x72, 0xB2, 0xF2, + 0x06, 0x46, 0x86, 0xC6, 0x16, 0x56, 0x96, 0xD6, + 0x26, 0x66, 0xA6, 0xE6, 0x36, 0x76, 0xB6, 0xF6, + 0x0A, 0x4A, 0x8A, 0xCA, 0x1A, 0x5A, 0x9A, 0xDA, + 0x2A, 0x6A, 0xAA, 0xEA, 0x3A, 0x7A, 0xBA, 0xFA, + 0x0E, 0x4E, 0x8E, 0xCE, 0x1E, 0x5E, 0x9E, 0xDE, + 0x2E, 0x6E, 0xAE, 0xEE, 0x3E, 0x7E, 0xBE, 0xFE, + 0x03, 0x43, 0x83, 0xC3, 0x13, 0x53, 0x93, 0xD3, + 0x23, 0x63, 0xA3, 0xE3, 0x33, 0x73, 0xB3, 0xF3, + 0x07, 0x47, 0x87, 0xC7, 0x17, 0x57, 0x97, 0xD7, + 0x27, 0x67, 0xA7, 0xE7, 0x37, 0x77, 0xB7, 0xF7, + 0x0B, 0x4B, 0x8B, 0xCB, 0x1B, 0x5B, 0x9B, 0xDB, + 0x2B, 0x6B, 0xAB, 0xEB, 0x3B, 0x7B, 0xBB, 0xFB, + 0x0F, 0x4F, 0x8F, 0xCF, 0x1F, 0x5F, 0x9F, 0xDF, + 0x2F, 0x6F, 0xAF, 0xEF, 0x3F, 0x7F, 0xBF, 0xFF +}; + +static PNG_CONST png_byte fourbppswaptable[256] = { + 0x00, 0x10, 0x20, 0x30, 0x40, 0x50, 0x60, 0x70, + 0x80, 0x90, 0xA0, 0xB0, 0xC0, 0xD0, 0xE0, 0xF0, + 0x01, 0x11, 0x21, 0x31, 0x41, 0x51, 0x61, 0x71, + 0x81, 0x91, 0xA1, 0xB1, 0xC1, 0xD1, 0xE1, 0xF1, + 0x02, 0x12, 0x22, 0x32, 0x42, 0x52, 0x62, 0x72, + 0x82, 0x92, 0xA2, 0xB2, 0xC2, 0xD2, 0xE2, 0xF2, + 0x03, 0x13, 0x23, 0x33, 0x43, 0x53, 0x63, 0x73, + 0x83, 0x93, 0xA3, 0xB3, 0xC3, 0xD3, 0xE3, 0xF3, + 0x04, 0x14, 0x24, 0x34, 0x44, 0x54, 0x64, 0x74, + 0x84, 0x94, 0xA4, 0xB4, 0xC4, 0xD4, 0xE4, 0xF4, + 0x05, 0x15, 0x25, 0x35, 0x45, 0x55, 0x65, 0x75, + 0x85, 0x95, 0xA5, 0xB5, 0xC5, 0xD5, 0xE5, 0xF5, + 0x06, 0x16, 0x26, 0x36, 0x46, 0x56, 0x66, 0x76, + 0x86, 0x96, 0xA6, 0xB6, 0xC6, 0xD6, 0xE6, 0xF6, + 0x07, 0x17, 0x27, 0x37, 0x47, 0x57, 0x67, 0x77, + 0x87, 0x97, 0xA7, 0xB7, 0xC7, 0xD7, 0xE7, 0xF7, + 0x08, 0x18, 0x28, 0x38, 0x48, 0x58, 0x68, 0x78, + 0x88, 0x98, 0xA8, 0xB8, 0xC8, 0xD8, 0xE8, 0xF8, + 0x09, 0x19, 0x29, 0x39, 0x49, 0x59, 0x69, 0x79, + 0x89, 0x99, 0xA9, 0xB9, 0xC9, 0xD9, 0xE9, 0xF9, + 0x0A, 0x1A, 0x2A, 0x3A, 0x4A, 0x5A, 0x6A, 0x7A, + 0x8A, 0x9A, 0xAA, 0xBA, 0xCA, 0xDA, 0xEA, 0xFA, + 0x0B, 0x1B, 0x2B, 0x3B, 0x4B, 0x5B, 0x6B, 0x7B, + 0x8B, 0x9B, 0xAB, 0xBB, 0xCB, 0xDB, 0xEB, 0xFB, + 0x0C, 0x1C, 0x2C, 0x3C, 0x4C, 0x5C, 0x6C, 0x7C, + 0x8C, 0x9C, 0xAC, 0xBC, 0xCC, 0xDC, 0xEC, 0xFC, + 0x0D, 0x1D, 0x2D, 0x3D, 0x4D, 0x5D, 0x6D, 0x7D, + 0x8D, 0x9D, 0xAD, 0xBD, 0xCD, 0xDD, 0xED, 0xFD, + 0x0E, 0x1E, 0x2E, 0x3E, 0x4E, 0x5E, 0x6E, 0x7E, + 0x8E, 0x9E, 0xAE, 0xBE, 0xCE, 0xDE, 0xEE, 0xFE, + 0x0F, 0x1F, 0x2F, 0x3F, 0x4F, 0x5F, 0x6F, 0x7F, + 0x8F, 0x9F, 0xAF, 0xBF, 0xCF, 0xDF, 0xEF, 0xFF +}; + +/* Swaps pixel packing order within bytes */ +void /* PRIVATE */ +png_do_packswap(png_row_infop row_info, png_bytep row) +{ + png_debug(1, "in png_do_packswap"); + + if ( + row_info->bit_depth < 8) + { + png_bytep rp, end, table; + + end = row + row_info->rowbytes; + + if (row_info->bit_depth == 1) + table = (png_bytep)onebppswaptable; + else if (row_info->bit_depth == 2) + table = (png_bytep)twobppswaptable; + else if (row_info->bit_depth == 4) + table = (png_bytep)fourbppswaptable; + else + return; + + for (rp = row; rp < end; rp++) + *rp = table[*rp]; + } +} +#endif /* PNG_READ_PACKSWAP_SUPPORTED or PNG_WRITE_PACKSWAP_SUPPORTED */ + +#if defined(PNG_WRITE_FILLER_SUPPORTED) || \ + defined(PNG_READ_STRIP_ALPHA_SUPPORTED) +/* Remove filler or alpha byte(s) */ +void /* PRIVATE */ +png_do_strip_filler(png_row_infop row_info, png_bytep row, png_uint_32 flags) +{ + png_debug(1, "in png_do_strip_filler"); + + { + png_bytep sp=row; + png_bytep dp=row; + png_uint_32 row_width=row_info->width; + png_uint_32 i; + + if ((row_info->color_type == PNG_COLOR_TYPE_RGB || + (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA && + (flags & PNG_FLAG_STRIP_ALPHA))) && + row_info->channels == 4) + { + if (row_info->bit_depth == 8) + { + /* This converts from RGBX or RGBA to RGB */ + if (flags & PNG_FLAG_FILLER_AFTER) + { + dp+=3; sp+=4; + for (i = 1; i < row_width; i++) + { + *dp++ = *sp++; + *dp++ = *sp++; + *dp++ = *sp++; + sp++; + } + } + /* This converts from XRGB or ARGB to RGB */ + else + { + for (i = 0; i < row_width; i++) + { + sp++; + *dp++ = *sp++; + *dp++ = *sp++; + *dp++ = *sp++; + } + } + row_info->pixel_depth = 24; + row_info->rowbytes = row_width * 3; + } + else /* if (row_info->bit_depth == 16) */ + { + if (flags & PNG_FLAG_FILLER_AFTER) + { + /* This converts from RRGGBBXX or RRGGBBAA to RRGGBB */ + sp += 8; dp += 6; + for (i = 1; i < row_width; i++) + { + /* This could be (although png_memcpy is probably slower): + png_memcpy(dp, sp, 6); + sp += 8; + dp += 6; + */ + + *dp++ = *sp++; + *dp++ = *sp++; + *dp++ = *sp++; + *dp++ = *sp++; + *dp++ = *sp++; + *dp++ = *sp++; + sp += 2; + } + } + else + { + /* This converts from XXRRGGBB or AARRGGBB to RRGGBB */ + for (i = 0; i < row_width; i++) + { + /* This could be (although png_memcpy is probably slower): + png_memcpy(dp, sp, 6); + sp += 8; + dp += 6; + */ + + sp+=2; + *dp++ = *sp++; + *dp++ = *sp++; + *dp++ = *sp++; + *dp++ = *sp++; + *dp++ = *sp++; + *dp++ = *sp++; + } + } + row_info->pixel_depth = 48; + row_info->rowbytes = row_width * 6; + } + row_info->channels = 3; + } + else if ((row_info->color_type == PNG_COLOR_TYPE_GRAY || + (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA && + (flags & PNG_FLAG_STRIP_ALPHA))) && + row_info->channels == 2) + { + if (row_info->bit_depth == 8) + { + /* This converts from GX or GA to G */ + if (flags & PNG_FLAG_FILLER_AFTER) + { + for (i = 0; i < row_width; i++) + { + *dp++ = *sp++; + sp++; + } + } + /* This converts from XG or AG to G */ + else + { + for (i = 0; i < row_width; i++) + { + sp++; + *dp++ = *sp++; + } + } + row_info->pixel_depth = 8; + row_info->rowbytes = row_width; + } + else /* if (row_info->bit_depth == 16) */ + { + if (flags & PNG_FLAG_FILLER_AFTER) + { + /* This converts from GGXX or GGAA to GG */ + sp += 4; dp += 2; + for (i = 1; i < row_width; i++) + { + *dp++ = *sp++; + *dp++ = *sp++; + sp += 2; + } + } + else + { + /* This converts from XXGG or AAGG to GG */ + for (i = 0; i < row_width; i++) + { + sp += 2; + *dp++ = *sp++; + *dp++ = *sp++; + } + } + row_info->pixel_depth = 16; + row_info->rowbytes = row_width * 2; + } + row_info->channels = 1; + } + if (flags & PNG_FLAG_STRIP_ALPHA) + row_info->color_type &= ~PNG_COLOR_MASK_ALPHA; + } +} +#endif + +#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED) +/* Swaps red and blue bytes within a pixel */ +void /* PRIVATE */ +png_do_bgr(png_row_infop row_info, png_bytep row) +{ + png_debug(1, "in png_do_bgr"); + + if ( + (row_info->color_type & PNG_COLOR_MASK_COLOR)) + { + png_uint_32 row_width = row_info->width; + if (row_info->bit_depth == 8) + { + if (row_info->color_type == PNG_COLOR_TYPE_RGB) + { + png_bytep rp; + png_uint_32 i; + + for (i = 0, rp = row; i < row_width; i++, rp += 3) + { + png_byte save = *rp; + *rp = *(rp + 2); + *(rp + 2) = save; + } + } + else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) + { + png_bytep rp; + png_uint_32 i; + + for (i = 0, rp = row; i < row_width; i++, rp += 4) + { + png_byte save = *rp; + *rp = *(rp + 2); + *(rp + 2) = save; + } + } + } + else if (row_info->bit_depth == 16) + { + if (row_info->color_type == PNG_COLOR_TYPE_RGB) + { + png_bytep rp; + png_uint_32 i; + + for (i = 0, rp = row; i < row_width; i++, rp += 6) + { + png_byte save = *rp; + *rp = *(rp + 4); + *(rp + 4) = save; + save = *(rp + 1); + *(rp + 1) = *(rp + 5); + *(rp + 5) = save; + } + } + else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) + { + png_bytep rp; + png_uint_32 i; + + for (i = 0, rp = row; i < row_width; i++, rp += 8) + { + png_byte save = *rp; + *rp = *(rp + 4); + *(rp + 4) = save; + save = *(rp + 1); + *(rp + 1) = *(rp + 5); + *(rp + 5) = save; + } + } + } + } +} +#endif /* PNG_READ_BGR_SUPPORTED or PNG_WRITE_BGR_SUPPORTED */ + +#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \ + defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) +void PNGAPI +png_set_user_transform_info(png_structp png_ptr, png_voidp + user_transform_ptr, int user_transform_depth, int user_transform_channels) +{ + png_debug(1, "in png_set_user_transform_info"); + + if (png_ptr == NULL) + return; +#ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED + png_ptr->user_transform_ptr = user_transform_ptr; + png_ptr->user_transform_depth = (png_byte)user_transform_depth; + png_ptr->user_transform_channels = (png_byte)user_transform_channels; +#else + if (user_transform_ptr || user_transform_depth || user_transform_channels) + png_warning(png_ptr, + "This version of libpng does not support user transform info"); +#endif +} + +/* This function returns a pointer to the user_transform_ptr associated with + * the user transform functions. The application should free any memory + * associated with this pointer before png_write_destroy and png_read_destroy + * are called. + */ +png_voidp PNGAPI +png_get_user_transform_ptr(png_structp png_ptr) +{ + if (png_ptr == NULL) + return (NULL); +#ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED + return ((png_voidp)png_ptr->user_transform_ptr); +#else + return (NULL); +#endif +} +#endif /* PNG_READ_USER_TRANSFORM_SUPPORTED || + PNG_WRITE_USER_TRANSFORM_SUPPORTED */ +#endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */ diff --git a/libpng/pngwio.c b/libpng/pngwio.c new file mode 100644 index 0000000..513a71a --- /dev/null +++ b/libpng/pngwio.c @@ -0,0 +1,241 @@ + +/* pngwio.c - functions for data output + * + * Last changed in libpng 1.4.0 [January 3, 2010] + * Copyright (c) 1998-2010 Glenn Randers-Pehrson + * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) + * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) + * + * This code is released under the libpng license. + * For conditions of distribution and use, see the disclaimer + * and license in png.h + * + * This file provides a location for all output. Users who need + * special handling are expected to write functions that have the same + * arguments as these and perform similar functions, but that possibly + * use different output methods. Note that you shouldn't change these + * functions, but rather write replacement functions and then change + * them at run time with png_set_write_fn(...). + */ + +#define PNG_NO_PEDANTIC_WARNINGS +#include "png.h" +#ifdef PNG_WRITE_SUPPORTED +#include "pngpriv.h" + +/* Write the data to whatever output you are using. The default routine + * writes to a file pointer. Note that this routine sometimes gets called + * with very small lengths, so you should implement some kind of simple + * buffering if you are using unbuffered writes. This should never be asked + * to write more than 64K on a 16 bit machine. + */ + +void /* PRIVATE */ +png_write_data(png_structp png_ptr, png_bytep data, png_size_t length) +{ + if (png_ptr->write_data_fn != NULL ) + (*(png_ptr->write_data_fn))(png_ptr, data, length); + else + png_error(png_ptr, "Call to NULL write function"); +} + +#ifdef PNG_STDIO_SUPPORTED +/* This is the function that does the actual writing of data. If you are + * not writing to a standard C stream, you should create a replacement + * write_data function and use it at run time with png_set_write_fn(), rather + * than changing the library. + */ +#ifndef USE_FAR_KEYWORD +void PNGAPI +png_default_write_data(png_structp png_ptr, png_bytep data, png_size_t length) +{ + png_uint_32 check; + + if (png_ptr == NULL) + return; + check = fwrite(data, 1, length, (png_FILE_p)(png_ptr->io_ptr)); + if (check != length) + png_error(png_ptr, "Write Error"); +} +#else +/* This is the model-independent version. Since the standard I/O library + * can't handle far buffers in the medium and small models, we have to copy + * the data. + */ + +#define NEAR_BUF_SIZE 1024 +#define MIN(a,b) (a <= b ? a : b) + +void PNGAPI +png_default_write_data(png_structp png_ptr, png_bytep data, png_size_t length) +{ + png_uint_32 check; + png_byte *near_data; /* Needs to be "png_byte *" instead of "png_bytep" */ + png_FILE_p io_ptr; + + if (png_ptr == NULL) + return; + /* Check if data really is near. If so, use usual code. */ + near_data = (png_byte *)CVT_PTR_NOCHECK(data); + io_ptr = (png_FILE_p)CVT_PTR(png_ptr->io_ptr); + if ((png_bytep)near_data == data) + { + check = fwrite(near_data, 1, length, io_ptr); + } + else + { + png_byte buf[NEAR_BUF_SIZE]; + png_size_t written, remaining, err; + check = 0; + remaining = length; + do + { + written = MIN(NEAR_BUF_SIZE, remaining); + png_memcpy(buf, data, written); /* Copy far buffer to near buffer */ + err = fwrite(buf, 1, written, io_ptr); + if (err != written) + break; + + else + check += err; + + data += written; + remaining -= written; + } + while (remaining != 0); + } + if (check != length) + png_error(png_ptr, "Write Error"); +} + +#endif +#endif + +/* This function is called to output any data pending writing (normally + * to disk). After png_flush is called, there should be no data pending + * writing in any buffers. + */ +#ifdef PNG_WRITE_FLUSH_SUPPORTED +void /* PRIVATE */ +png_flush(png_structp png_ptr) +{ + if (png_ptr->output_flush_fn != NULL) + (*(png_ptr->output_flush_fn))(png_ptr); +} + +#ifdef PNG_STDIO_SUPPORTED +void PNGAPI +png_default_flush(png_structp png_ptr) +{ + png_FILE_p io_ptr; + if (png_ptr == NULL) + return; + io_ptr = (png_FILE_p)CVT_PTR((png_ptr->io_ptr)); + fflush(io_ptr); +} +#endif +#endif + +/* This function allows the application to supply new output functions for + * libpng if standard C streams aren't being used. + * + * This function takes as its arguments: + * png_ptr - pointer to a png output data structure + * io_ptr - pointer to user supplied structure containing info about + * the output functions. May be NULL. + * write_data_fn - pointer to a new output function that takes as its + * arguments a pointer to a png_struct, a pointer to + * data to be written, and a 32-bit unsigned int that is + * the number of bytes to be written. The new write + * function should call png_error(png_ptr, "Error msg") + * to exit and output any fatal error messages. May be + * NULL, in which case libpng's default function will + * be used. + * flush_data_fn - pointer to a new flush function that takes as its + * arguments a pointer to a png_struct. After a call to + * the flush function, there should be no data in any buffers + * or pending transmission. If the output method doesn't do + * any buffering of output, a function prototype must still be + * supplied although it doesn't have to do anything. If + * PNG_WRITE_FLUSH_SUPPORTED is not defined at libpng compile + * time, output_flush_fn will be ignored, although it must be + * supplied for compatibility. May be NULL, in which case + * libpng's default function will be used, if + * PNG_WRITE_FLUSH_SUPPORTED is defined. This is not + * a good idea if io_ptr does not point to a standard + * *FILE structure. + */ +void PNGAPI +png_set_write_fn(png_structp png_ptr, png_voidp io_ptr, + png_rw_ptr write_data_fn, png_flush_ptr output_flush_fn) +{ + if (png_ptr == NULL) + return; + + png_ptr->io_ptr = io_ptr; + +#ifdef PNG_STDIO_SUPPORTED + if (write_data_fn != NULL) + png_ptr->write_data_fn = write_data_fn; + + else + png_ptr->write_data_fn = png_default_write_data; +#else + png_ptr->write_data_fn = write_data_fn; +#endif + +#ifdef PNG_WRITE_FLUSH_SUPPORTED +#ifdef PNG_STDIO_SUPPORTED + if (output_flush_fn != NULL) + png_ptr->output_flush_fn = output_flush_fn; + + else + png_ptr->output_flush_fn = png_default_flush; +#else + png_ptr->output_flush_fn = output_flush_fn; +#endif +#endif /* PNG_WRITE_FLUSH_SUPPORTED */ + + /* It is an error to read while writing a png file */ + if (png_ptr->read_data_fn != NULL) + { + png_ptr->read_data_fn = NULL; + png_warning(png_ptr, + "Attempted to set both read_data_fn and write_data_fn in"); + png_warning(png_ptr, + "the same structure. Resetting read_data_fn to NULL"); + } +} + +#ifdef USE_FAR_KEYWORD +#ifdef _MSC_VER +void *png_far_to_near(png_structp png_ptr, png_voidp ptr, int check) +{ + void *near_ptr; + void FAR *far_ptr; + FP_OFF(near_ptr) = FP_OFF(ptr); + far_ptr = (void FAR *)near_ptr; + + if (check != 0) + if (FP_SEG(ptr) != FP_SEG(far_ptr)) + png_error(png_ptr, "segment lost in conversion"); + + return(near_ptr); +} +# else +void *png_far_to_near(png_structp png_ptr, png_voidp ptr, int check) +{ + void *near_ptr; + void FAR *far_ptr; + near_ptr = (void FAR *)ptr; + far_ptr = (void FAR *)near_ptr; + + if (check != 0) + if (far_ptr != ptr) + png_error(png_ptr, "segment lost in conversion"); + + return(near_ptr); +} +# endif +# endif +#endif /* PNG_WRITE_SUPPORTED */ diff --git a/libpng/pngwrite.c b/libpng/pngwrite.c new file mode 100644 index 0000000..0252051 --- /dev/null +++ b/libpng/pngwrite.c @@ -0,0 +1,1457 @@ + +/* pngwrite.c - general routines to write a PNG file + * + * Last changed in libpng 1.4.0 [January 3, 2010] + * Copyright (c) 1998-2010 Glenn Randers-Pehrson + * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) + * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) + * + * This code is released under the libpng license. + * For conditions of distribution and use, see the disclaimer + * and license in png.h + */ + +/* Get internal access to png.h */ +#define PNG_NO_PEDANTIC_WARNINGS +#include "png.h" +#ifdef PNG_WRITE_SUPPORTED +#include "pngpriv.h" + +/* Writes all the PNG information. This is the suggested way to use the + * library. If you have a new chunk to add, make a function to write it, + * and put it in the correct location here. If you want the chunk written + * after the image data, put it in png_write_end(). I strongly encourage + * you to supply a PNG_INFO_ flag, and check info_ptr->valid before writing + * the chunk, as that will keep the code from breaking if you want to just + * write a plain PNG file. If you have long comments, I suggest writing + * them in png_write_end(), and compressing them. + */ +void PNGAPI +png_write_info_before_PLTE(png_structp png_ptr, png_infop info_ptr) +{ + png_debug(1, "in png_write_info_before_PLTE"); + + if (png_ptr == NULL || info_ptr == NULL) + return; + if (!(png_ptr->mode & PNG_WROTE_INFO_BEFORE_PLTE)) + { + /* Write PNG signature */ + png_write_sig(png_ptr); +#ifdef PNG_MNG_FEATURES_SUPPORTED + if ((png_ptr->mode&PNG_HAVE_PNG_SIGNATURE) && \ + (png_ptr->mng_features_permitted)) + { + png_warning(png_ptr, "MNG features are not allowed in a PNG datastream"); + png_ptr->mng_features_permitted = 0; + } +#endif + /* Write IHDR information. */ + png_write_IHDR(png_ptr, info_ptr->width, info_ptr->height, + info_ptr->bit_depth, info_ptr->color_type, info_ptr->compression_type, + info_ptr->filter_type, +#ifdef PNG_WRITE_INTERLACING_SUPPORTED + info_ptr->interlace_type); +#else + 0); +#endif + /* The rest of these check to see if the valid field has the appropriate + * flag set, and if it does, writes the chunk. + */ +#ifdef PNG_WRITE_gAMA_SUPPORTED + if (info_ptr->valid & PNG_INFO_gAMA) + { +# ifdef PNG_FLOATING_POINT_SUPPORTED + png_write_gAMA(png_ptr, info_ptr->gamma); +#else +#ifdef PNG_FIXED_POINT_SUPPORTED + png_write_gAMA_fixed(png_ptr, info_ptr->int_gamma); +# endif +#endif + } +#endif +#ifdef PNG_WRITE_sRGB_SUPPORTED + if (info_ptr->valid & PNG_INFO_sRGB) + png_write_sRGB(png_ptr, (int)info_ptr->srgb_intent); +#endif +#ifdef PNG_WRITE_iCCP_SUPPORTED + if (info_ptr->valid & PNG_INFO_iCCP) + png_write_iCCP(png_ptr, info_ptr->iccp_name, PNG_COMPRESSION_TYPE_BASE, + info_ptr->iccp_profile, (int)info_ptr->iccp_proflen); +#endif +#ifdef PNG_WRITE_sBIT_SUPPORTED + if (info_ptr->valid & PNG_INFO_sBIT) + png_write_sBIT(png_ptr, &(info_ptr->sig_bit), info_ptr->color_type); +#endif +#ifdef PNG_WRITE_cHRM_SUPPORTED + if (info_ptr->valid & PNG_INFO_cHRM) + { +#ifdef PNG_FLOATING_POINT_SUPPORTED + png_write_cHRM(png_ptr, + info_ptr->x_white, info_ptr->y_white, + info_ptr->x_red, info_ptr->y_red, + info_ptr->x_green, info_ptr->y_green, + info_ptr->x_blue, info_ptr->y_blue); +#else +# ifdef PNG_FIXED_POINT_SUPPORTED + png_write_cHRM_fixed(png_ptr, + info_ptr->int_x_white, info_ptr->int_y_white, + info_ptr->int_x_red, info_ptr->int_y_red, + info_ptr->int_x_green, info_ptr->int_y_green, + info_ptr->int_x_blue, info_ptr->int_y_blue); +# endif +#endif + } +#endif +#ifdef PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED + if (info_ptr->unknown_chunks_num) + { + png_unknown_chunk *up; + + png_debug(5, "writing extra chunks"); + + for (up = info_ptr->unknown_chunks; + up < info_ptr->unknown_chunks + info_ptr->unknown_chunks_num; + up++) + { + int keep = png_handle_as_unknown(png_ptr, up->name); + if (keep != PNG_HANDLE_CHUNK_NEVER && + up->location && !(up->location & PNG_HAVE_PLTE) && + !(up->location & PNG_HAVE_IDAT) && + ((up->name[3] & 0x20) || keep == PNG_HANDLE_CHUNK_ALWAYS || + (png_ptr->flags & PNG_FLAG_KEEP_UNSAFE_CHUNKS))) + { + if (up->size == 0) + png_warning(png_ptr, "Writing zero-length unknown chunk"); + png_write_chunk(png_ptr, up->name, up->data, up->size); + } + } + } +#endif + png_ptr->mode |= PNG_WROTE_INFO_BEFORE_PLTE; + } +} + +void PNGAPI +png_write_info(png_structp png_ptr, png_infop info_ptr) +{ +#if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED) + int i; +#endif + + png_debug(1, "in png_write_info"); + + if (png_ptr == NULL || info_ptr == NULL) + return; + + png_write_info_before_PLTE(png_ptr, info_ptr); + + if (info_ptr->valid & PNG_INFO_PLTE) + png_write_PLTE(png_ptr, info_ptr->palette, + (png_uint_32)info_ptr->num_palette); + else if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE) + png_error(png_ptr, "Valid palette required for paletted images"); + +#ifdef PNG_WRITE_tRNS_SUPPORTED + if (info_ptr->valid & PNG_INFO_tRNS) + { +#ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED + /* Invert the alpha channel (in tRNS) */ + if ((png_ptr->transformations & PNG_INVERT_ALPHA) && + info_ptr->color_type == PNG_COLOR_TYPE_PALETTE) + { + int j; + for (j = 0; j<(int)info_ptr->num_trans; j++) + info_ptr->trans_alpha[j] = (png_byte)(255 - info_ptr->trans_alpha[j]); + } +#endif + png_write_tRNS(png_ptr, info_ptr->trans_alpha, &(info_ptr->trans_color), + info_ptr->num_trans, info_ptr->color_type); + } +#endif +#ifdef PNG_WRITE_bKGD_SUPPORTED + if (info_ptr->valid & PNG_INFO_bKGD) + png_write_bKGD(png_ptr, &(info_ptr->background), info_ptr->color_type); +#endif +#ifdef PNG_WRITE_hIST_SUPPORTED + if (info_ptr->valid & PNG_INFO_hIST) + png_write_hIST(png_ptr, info_ptr->hist, info_ptr->num_palette); +#endif +#ifdef PNG_WRITE_oFFs_SUPPORTED + if (info_ptr->valid & PNG_INFO_oFFs) + png_write_oFFs(png_ptr, info_ptr->x_offset, info_ptr->y_offset, + info_ptr->offset_unit_type); +#endif +#ifdef PNG_WRITE_pCAL_SUPPORTED + if (info_ptr->valid & PNG_INFO_pCAL) + png_write_pCAL(png_ptr, info_ptr->pcal_purpose, info_ptr->pcal_X0, + info_ptr->pcal_X1, info_ptr->pcal_type, info_ptr->pcal_nparams, + info_ptr->pcal_units, info_ptr->pcal_params); +#endif + +#ifdef PNG_sCAL_SUPPORTED + if (info_ptr->valid & PNG_INFO_sCAL) +#ifdef PNG_WRITE_sCAL_SUPPORTED +#if defined(PNG_FLOATING_POINT_SUPPORTED) && defined(PNG_STDIO_SUPPORTED) + png_write_sCAL(png_ptr, (int)info_ptr->scal_unit, + info_ptr->scal_pixel_width, info_ptr->scal_pixel_height); +#else /* !FLOATING_POINT */ +#ifdef PNG_FIXED_POINT_SUPPORTED + png_write_sCAL_s(png_ptr, (int)info_ptr->scal_unit, + info_ptr->scal_s_width, info_ptr->scal_s_height); +#endif /* FIXED_POINT */ +#endif /* FLOATING_POINT */ +#else /* !WRITE_sCAL */ + png_warning(png_ptr, + "png_write_sCAL not supported; sCAL chunk not written"); +#endif /* WRITE_sCAL */ +#endif /* sCAL */ + +#ifdef PNG_WRITE_pHYs_SUPPORTED + if (info_ptr->valid & PNG_INFO_pHYs) + png_write_pHYs(png_ptr, info_ptr->x_pixels_per_unit, + info_ptr->y_pixels_per_unit, info_ptr->phys_unit_type); +#endif /* pHYs */ + +#ifdef PNG_WRITE_tIME_SUPPORTED + if (info_ptr->valid & PNG_INFO_tIME) + { + png_write_tIME(png_ptr, &(info_ptr->mod_time)); + png_ptr->mode |= PNG_WROTE_tIME; + } +#endif /* tIME */ + +#ifdef PNG_WRITE_sPLT_SUPPORTED + if (info_ptr->valid & PNG_INFO_sPLT) + for (i = 0; i < (int)info_ptr->splt_palettes_num; i++) + png_write_sPLT(png_ptr, info_ptr->splt_palettes + i); +#endif /* sPLT */ + +#ifdef PNG_WRITE_TEXT_SUPPORTED + /* Check to see if we need to write text chunks */ + for (i = 0; i < info_ptr->num_text; i++) + { + png_debug2(2, "Writing header text chunk %d, type %d", i, + info_ptr->text[i].compression); + /* An internationalized chunk? */ + if (info_ptr->text[i].compression > 0) + { +#ifdef PNG_WRITE_iTXt_SUPPORTED + /* Write international chunk */ + png_write_iTXt(png_ptr, + info_ptr->text[i].compression, + info_ptr->text[i].key, + info_ptr->text[i].lang, + info_ptr->text[i].lang_key, + info_ptr->text[i].text); +#else + png_warning(png_ptr, "Unable to write international text"); +#endif + /* Mark this chunk as written */ + info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR; + } + /* If we want a compressed text chunk */ + else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_zTXt) + { +#ifdef PNG_WRITE_zTXt_SUPPORTED + /* Write compressed chunk */ + png_write_zTXt(png_ptr, info_ptr->text[i].key, + info_ptr->text[i].text, 0, + info_ptr->text[i].compression); +#else + png_warning(png_ptr, "Unable to write compressed text"); +#endif + /* Mark this chunk as written */ + info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR; + } + else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_NONE) + { +#ifdef PNG_WRITE_tEXt_SUPPORTED + /* Write uncompressed chunk */ + png_write_tEXt(png_ptr, info_ptr->text[i].key, + info_ptr->text[i].text, + 0); + /* Mark this chunk as written */ + info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR; +#else + /* Can't get here */ + png_warning(png_ptr, "Unable to write uncompressed text"); +#endif + } + } +#endif /* tEXt */ + +#ifdef PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED + if (info_ptr->unknown_chunks_num) + { + png_unknown_chunk *up; + + png_debug(5, "writing extra chunks"); + + for (up = info_ptr->unknown_chunks; + up < info_ptr->unknown_chunks + info_ptr->unknown_chunks_num; + up++) + { + int keep = png_handle_as_unknown(png_ptr, up->name); + if (keep != PNG_HANDLE_CHUNK_NEVER && + up->location && (up->location & PNG_HAVE_PLTE) && + !(up->location & PNG_HAVE_IDAT) && + ((up->name[3] & 0x20) || keep == PNG_HANDLE_CHUNK_ALWAYS || + (png_ptr->flags & PNG_FLAG_KEEP_UNSAFE_CHUNKS))) + { + png_write_chunk(png_ptr, up->name, up->data, up->size); + } + } + } +#endif +} + +/* Writes the end of the PNG file. If you don't want to write comments or + * time information, you can pass NULL for info. If you already wrote these + * in png_write_info(), do not write them again here. If you have long + * comments, I suggest writing them here, and compressing them. + */ +void PNGAPI +png_write_end(png_structp png_ptr, png_infop info_ptr) +{ + png_debug(1, "in png_write_end"); + + if (png_ptr == NULL) + return; + if (!(png_ptr->mode & PNG_HAVE_IDAT)) + png_error(png_ptr, "No IDATs written into file"); + + /* See if user wants us to write information chunks */ + if (info_ptr != NULL) + { +#ifdef PNG_WRITE_TEXT_SUPPORTED + int i; /* local index variable */ +#endif +#ifdef PNG_WRITE_tIME_SUPPORTED + /* Check to see if user has supplied a time chunk */ + if ((info_ptr->valid & PNG_INFO_tIME) && + !(png_ptr->mode & PNG_WROTE_tIME)) + png_write_tIME(png_ptr, &(info_ptr->mod_time)); +#endif +#ifdef PNG_WRITE_TEXT_SUPPORTED + /* Loop through comment chunks */ + for (i = 0; i < info_ptr->num_text; i++) + { + png_debug2(2, "Writing trailer text chunk %d, type %d", i, + info_ptr->text[i].compression); + /* An internationalized chunk? */ + if (info_ptr->text[i].compression > 0) + { +#ifdef PNG_WRITE_iTXt_SUPPORTED + /* Write international chunk */ + png_write_iTXt(png_ptr, + info_ptr->text[i].compression, + info_ptr->text[i].key, + info_ptr->text[i].lang, + info_ptr->text[i].lang_key, + info_ptr->text[i].text); +#else + png_warning(png_ptr, "Unable to write international text"); +#endif + /* Mark this chunk as written */ + info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR; + } + else if (info_ptr->text[i].compression >= PNG_TEXT_COMPRESSION_zTXt) + { +#ifdef PNG_WRITE_zTXt_SUPPORTED + /* Write compressed chunk */ + png_write_zTXt(png_ptr, info_ptr->text[i].key, + info_ptr->text[i].text, 0, + info_ptr->text[i].compression); +#else + png_warning(png_ptr, "Unable to write compressed text"); +#endif + /* Mark this chunk as written */ + info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR; + } + else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_NONE) + { +#ifdef PNG_WRITE_tEXt_SUPPORTED + /* Write uncompressed chunk */ + png_write_tEXt(png_ptr, info_ptr->text[i].key, + info_ptr->text[i].text, 0); +#else + png_warning(png_ptr, "Unable to write uncompressed text"); +#endif + + /* Mark this chunk as written */ + info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR; + } + } +#endif +#ifdef PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED + if (info_ptr->unknown_chunks_num) + { + png_unknown_chunk *up; + + png_debug(5, "writing extra chunks"); + + for (up = info_ptr->unknown_chunks; + up < info_ptr->unknown_chunks + info_ptr->unknown_chunks_num; + up++) + { + int keep = png_handle_as_unknown(png_ptr, up->name); + if (keep != PNG_HANDLE_CHUNK_NEVER && + up->location && (up->location & PNG_AFTER_IDAT) && + ((up->name[3] & 0x20) || keep == PNG_HANDLE_CHUNK_ALWAYS || + (png_ptr->flags & PNG_FLAG_KEEP_UNSAFE_CHUNKS))) + { + png_write_chunk(png_ptr, up->name, up->data, up->size); + } + } + } +#endif + } + + png_ptr->mode |= PNG_AFTER_IDAT; + + /* Write end of PNG file */ + png_write_IEND(png_ptr); + /* This flush, added in libpng-1.0.8, removed from libpng-1.0.9beta03, + * and restored again in libpng-1.2.30, may cause some applications that + * do not set png_ptr->output_flush_fn to crash. If your application + * experiences a problem, please try building libpng with + * PNG_WRITE_FLUSH_AFTER_IEND_SUPPORTED defined, and report the event to + * png-mng-implement at lists.sf.net . + */ +#ifdef PNG_WRITE_FLUSH_SUPPORTED +# ifdef PNG_WRITE_FLUSH_AFTER_IEND_SUPPORTED + png_flush(png_ptr); +# endif +#endif +} + +#ifdef PNG_CONVERT_tIME_SUPPORTED +/* "tm" structure is not supported on WindowsCE */ +void PNGAPI +png_convert_from_struct_tm(png_timep ptime, struct tm FAR * ttime) +{ + png_debug(1, "in png_convert_from_struct_tm"); + + ptime->year = (png_uint_16)(1900 + ttime->tm_year); + ptime->month = (png_byte)(ttime->tm_mon + 1); + ptime->day = (png_byte)ttime->tm_mday; + ptime->hour = (png_byte)ttime->tm_hour; + ptime->minute = (png_byte)ttime->tm_min; + ptime->second = (png_byte)ttime->tm_sec; +} + +void PNGAPI +png_convert_from_time_t(png_timep ptime, time_t ttime) +{ + struct tm *tbuf; + + png_debug(1, "in png_convert_from_time_t"); + + tbuf = gmtime(&ttime); + png_convert_from_struct_tm(ptime, tbuf); +} +#endif + +/* Initialize png_ptr structure, and allocate any memory needed */ +png_structp PNGAPI +png_create_write_struct(png_const_charp user_png_ver, png_voidp error_ptr, + png_error_ptr error_fn, png_error_ptr warn_fn) +{ +#ifdef PNG_USER_MEM_SUPPORTED + return (png_create_write_struct_2(user_png_ver, error_ptr, error_fn, + warn_fn, NULL, NULL, NULL)); +} + +/* Alternate initialize png_ptr structure, and allocate any memory needed */ +png_structp PNGAPI +png_create_write_struct_2(png_const_charp user_png_ver, png_voidp error_ptr, + png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr, + png_malloc_ptr malloc_fn, png_free_ptr free_fn) +{ +#endif /* PNG_USER_MEM_SUPPORTED */ + volatile int png_cleanup_needed = 0; +#ifdef PNG_SETJMP_SUPPORTED + volatile +#endif + png_structp png_ptr; +#ifdef PNG_SETJMP_SUPPORTED +#ifdef USE_FAR_KEYWORD + jmp_buf jmpbuf; +#endif +#endif + int i; + + png_debug(1, "in png_create_write_struct"); + +#ifdef PNG_USER_MEM_SUPPORTED + png_ptr = (png_structp)png_create_struct_2(PNG_STRUCT_PNG, + (png_malloc_ptr)malloc_fn, (png_voidp)mem_ptr); +#else + png_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG); +#endif /* PNG_USER_MEM_SUPPORTED */ + if (png_ptr == NULL) + return (NULL); + + /* Added at libpng-1.2.6 */ +#ifdef PNG_SET_USER_LIMITS_SUPPORTED + png_ptr->user_width_max = PNG_USER_WIDTH_MAX; + png_ptr->user_height_max = PNG_USER_HEIGHT_MAX; +#endif + +#ifdef PNG_SETJMP_SUPPORTED +/* Applications that neglect to set up their own setjmp() and then + encounter a png_error() will longjmp here. Since the jmpbuf is + then meaningless we abort instead of returning. */ +#ifdef USE_FAR_KEYWORD + if (setjmp(jmpbuf)) +#else + if (setjmp(png_jmpbuf(png_ptr))) /* sets longjmp to match setjmp */ +#endif +#ifdef USE_FAR_KEYWORD + png_memcpy(png_jmpbuf(png_ptr), jmpbuf, png_sizeof(jmp_buf)); +#endif + PNG_ABORT(); +#endif + +#ifdef PNG_USER_MEM_SUPPORTED + png_set_mem_fn(png_ptr, mem_ptr, malloc_fn, free_fn); +#endif /* PNG_USER_MEM_SUPPORTED */ + png_set_error_fn(png_ptr, error_ptr, error_fn, warn_fn); + + if (user_png_ver) + { + i = 0; + do + { + if (user_png_ver[i] != png_libpng_ver[i]) + png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH; + } while (png_libpng_ver[i++]); + } + + if (png_ptr->flags & PNG_FLAG_LIBRARY_MISMATCH) + { + /* Libpng 0.90 and later are binary incompatible with libpng 0.89, so + * we must recompile any applications that use any older library version. + * For versions after libpng 1.0, we will be compatible, so we need + * only check the first digit. + */ + if (user_png_ver == NULL || user_png_ver[0] != png_libpng_ver[0] || + (user_png_ver[0] == '1' && user_png_ver[2] != png_libpng_ver[2]) || + (user_png_ver[0] == '0' && user_png_ver[2] < '9')) + { +#ifdef PNG_STDIO_SUPPORTED + char msg[80]; + if (user_png_ver) + { + png_snprintf(msg, 80, + "Application was compiled with png.h from libpng-%.20s", + user_png_ver); + png_warning(png_ptr, msg); + } + png_snprintf(msg, 80, + "Application is running with png.c from libpng-%.20s", + png_libpng_ver); + png_warning(png_ptr, msg); +#endif +#ifdef PNG_ERROR_NUMBERS_SUPPORTED + png_ptr->flags = 0; +#endif + png_warning(png_ptr, + "Incompatible libpng version in application and library"); + png_cleanup_needed = 1; + } + } + + /* Initialize zbuf - compression buffer */ + png_ptr->zbuf_size = PNG_ZBUF_SIZE; + if (!png_cleanup_needed) + { + png_ptr->zbuf = (png_bytep)png_malloc_warn(png_ptr, + png_ptr->zbuf_size); + if (png_ptr->zbuf == NULL) + png_cleanup_needed = 1; + } + if (png_cleanup_needed) + { + /* Clean up PNG structure and deallocate any memory. */ + png_free(png_ptr, png_ptr->zbuf); + png_ptr->zbuf = NULL; +#ifdef PNG_USER_MEM_SUPPORTED + png_destroy_struct_2((png_voidp)png_ptr, + (png_free_ptr)free_fn, (png_voidp)mem_ptr); +#else + png_destroy_struct((png_voidp)png_ptr); +#endif + return (NULL); + } + + png_set_write_fn(png_ptr, NULL, NULL, NULL); + +#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED + png_set_filter_heuristics(png_ptr, PNG_FILTER_HEURISTIC_DEFAULT, + 1, NULL, NULL); +#endif + + return (png_ptr); +} + + +/* Write a few rows of image data. If the image is interlaced, + * either you will have to write the 7 sub images, or, if you + * have called png_set_interlace_handling(), you will have to + * "write" the image seven times. + */ +void PNGAPI +png_write_rows(png_structp png_ptr, png_bytepp row, + png_uint_32 num_rows) +{ + png_uint_32 i; /* row counter */ + png_bytepp rp; /* row pointer */ + + png_debug(1, "in png_write_rows"); + + if (png_ptr == NULL) + return; + + /* Loop through the rows */ + for (i = 0, rp = row; i < num_rows; i++, rp++) + { + png_write_row(png_ptr, *rp); + } +} + +/* Write the image. You only need to call this function once, even + * if you are writing an interlaced image. + */ +void PNGAPI +png_write_image(png_structp png_ptr, png_bytepp image) +{ + png_uint_32 i; /* row index */ + int pass, num_pass; /* pass variables */ + png_bytepp rp; /* points to current row */ + + if (png_ptr == NULL) + return; + + png_debug(1, "in png_write_image"); + +#ifdef PNG_WRITE_INTERLACING_SUPPORTED + /* Initialize interlace handling. If image is not interlaced, + * this will set pass to 1 + */ + num_pass = png_set_interlace_handling(png_ptr); +#else + num_pass = 1; +#endif + /* Loop through passes */ + for (pass = 0; pass < num_pass; pass++) + { + /* Loop through image */ + for (i = 0, rp = image; i < png_ptr->height; i++, rp++) + { + png_write_row(png_ptr, *rp); + } + } +} + +/* Called by user to write a row of image data */ +void PNGAPI +png_write_row(png_structp png_ptr, png_bytep row) +{ + if (png_ptr == NULL) + return; + + png_debug2(1, "in png_write_row (row %ld, pass %d)", + png_ptr->row_number, png_ptr->pass); + + /* Initialize transformations and other stuff if first time */ + if (png_ptr->row_number == 0 && png_ptr->pass == 0) + { + /* Make sure we wrote the header info */ + if (!(png_ptr->mode & PNG_WROTE_INFO_BEFORE_PLTE)) + png_error(png_ptr, + "png_write_info was never called before png_write_row"); + + /* Check for transforms that have been set but were defined out */ +#if !defined(PNG_WRITE_INVERT_SUPPORTED) && defined(PNG_READ_INVERT_SUPPORTED) + if (png_ptr->transformations & PNG_INVERT_MONO) + png_warning(png_ptr, "PNG_WRITE_INVERT_SUPPORTED is not defined"); +#endif +#if !defined(PNG_WRITE_FILLER_SUPPORTED) && defined(PNG_READ_FILLER_SUPPORTED) + if (png_ptr->transformations & PNG_FILLER) + png_warning(png_ptr, "PNG_WRITE_FILLER_SUPPORTED is not defined"); +#endif +#if !defined(PNG_WRITE_PACKSWAP_SUPPORTED) && \ + defined(PNG_READ_PACKSWAP_SUPPORTED) + if (png_ptr->transformations & PNG_PACKSWAP) + png_warning(png_ptr, + "PNG_WRITE_PACKSWAP_SUPPORTED is not defined"); +#endif +#if !defined(PNG_WRITE_PACK_SUPPORTED) && defined(PNG_READ_PACK_SUPPORTED) + if (png_ptr->transformations & PNG_PACK) + png_warning(png_ptr, "PNG_WRITE_PACK_SUPPORTED is not defined"); +#endif +#if !defined(PNG_WRITE_SHIFT_SUPPORTED) && defined(PNG_READ_SHIFT_SUPPORTED) + if (png_ptr->transformations & PNG_SHIFT) + png_warning(png_ptr, "PNG_WRITE_SHIFT_SUPPORTED is not defined"); +#endif +#if !defined(PNG_WRITE_BGR_SUPPORTED) && defined(PNG_READ_BGR_SUPPORTED) + if (png_ptr->transformations & PNG_BGR) + png_warning(png_ptr, "PNG_WRITE_BGR_SUPPORTED is not defined"); +#endif +#if !defined(PNG_WRITE_SWAP_SUPPORTED) && defined(PNG_READ_SWAP_SUPPORTED) + if (png_ptr->transformations & PNG_SWAP_BYTES) + png_warning(png_ptr, "PNG_WRITE_SWAP_SUPPORTED is not defined"); +#endif + + png_write_start_row(png_ptr); + } + +#ifdef PNG_WRITE_INTERLACING_SUPPORTED + /* If interlaced and not interested in row, return */ + if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE)) + { + switch (png_ptr->pass) + { + case 0: + if (png_ptr->row_number & 0x07) + { + png_write_finish_row(png_ptr); + return; + } + break; + case 1: + if ((png_ptr->row_number & 0x07) || png_ptr->width < 5) + { + png_write_finish_row(png_ptr); + return; + } + break; + case 2: + if ((png_ptr->row_number & 0x07) != 4) + { + png_write_finish_row(png_ptr); + return; + } + break; + case 3: + if ((png_ptr->row_number & 0x03) || png_ptr->width < 3) + { + png_write_finish_row(png_ptr); + return; + } + break; + case 4: + if ((png_ptr->row_number & 0x03) != 2) + { + png_write_finish_row(png_ptr); + return; + } + break; + case 5: + if ((png_ptr->row_number & 0x01) || png_ptr->width < 2) + { + png_write_finish_row(png_ptr); + return; + } + break; + case 6: + if (!(png_ptr->row_number & 0x01)) + { + png_write_finish_row(png_ptr); + return; + } + break; + } + } +#endif + + /* Set up row info for transformations */ + png_ptr->row_info.color_type = png_ptr->color_type; + png_ptr->row_info.width = png_ptr->usr_width; + png_ptr->row_info.channels = png_ptr->usr_channels; + png_ptr->row_info.bit_depth = png_ptr->usr_bit_depth; + png_ptr->row_info.pixel_depth = (png_byte)(png_ptr->row_info.bit_depth * + png_ptr->row_info.channels); + + png_ptr->row_info.rowbytes = PNG_ROWBYTES(png_ptr->row_info.pixel_depth, + png_ptr->row_info.width); + + png_debug1(3, "row_info->color_type = %d", png_ptr->row_info.color_type); + png_debug1(3, "row_info->width = %lu", png_ptr->row_info.width); + png_debug1(3, "row_info->channels = %d", png_ptr->row_info.channels); + png_debug1(3, "row_info->bit_depth = %d", png_ptr->row_info.bit_depth); + png_debug1(3, "row_info->pixel_depth = %d", png_ptr->row_info.pixel_depth); + png_debug1(3, "row_info->rowbytes = %lu", png_ptr->row_info.rowbytes); + + /* Copy user's row into buffer, leaving room for filter byte. */ + png_memcpy(png_ptr->row_buf + 1, row, png_ptr->row_info.rowbytes); + +#ifdef PNG_WRITE_INTERLACING_SUPPORTED + /* Handle interlacing */ + if (png_ptr->interlaced && png_ptr->pass < 6 && + (png_ptr->transformations & PNG_INTERLACE)) + { + png_do_write_interlace(&(png_ptr->row_info), + png_ptr->row_buf + 1, png_ptr->pass); + /* This should always get caught above, but still ... */ + if (!(png_ptr->row_info.width)) + { + png_write_finish_row(png_ptr); + return; + } + } +#endif + + /* Handle other transformations */ + if (png_ptr->transformations) + png_do_write_transformations(png_ptr); + +#ifdef PNG_MNG_FEATURES_SUPPORTED + /* Write filter_method 64 (intrapixel differencing) only if + * 1. Libpng was compiled with PNG_MNG_FEATURES_SUPPORTED and + * 2. Libpng did not write a PNG signature (this filter_method is only + * used in PNG datastreams that are embedded in MNG datastreams) and + * 3. The application called png_permit_mng_features with a mask that + * included PNG_FLAG_MNG_FILTER_64 and + * 4. The filter_method is 64 and + * 5. The color_type is RGB or RGBA + */ + if ((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) && + (png_ptr->filter_type == PNG_INTRAPIXEL_DIFFERENCING)) + { + /* Intrapixel differencing */ + png_do_write_intrapixel(&(png_ptr->row_info), png_ptr->row_buf + 1); + } +#endif + + /* Find a filter if necessary, filter the row and write it out. */ + png_write_find_filter(png_ptr, &(png_ptr->row_info)); + + if (png_ptr->write_row_fn != NULL) + (*(png_ptr->write_row_fn))(png_ptr, png_ptr->row_number, png_ptr->pass); +} + +#ifdef PNG_WRITE_FLUSH_SUPPORTED +/* Set the automatic flush interval or 0 to turn flushing off */ +void PNGAPI +png_set_flush(png_structp png_ptr, int nrows) +{ + png_debug(1, "in png_set_flush"); + + if (png_ptr == NULL) + return; + png_ptr->flush_dist = (nrows < 0 ? 0 : nrows); +} + +/* Flush the current output buffers now */ +void PNGAPI +png_write_flush(png_structp png_ptr) +{ + int wrote_IDAT; + + png_debug(1, "in png_write_flush"); + + if (png_ptr == NULL) + return; + /* We have already written out all of the data */ + if (png_ptr->row_number >= png_ptr->num_rows) + return; + + do + { + int ret; + + /* Compress the data */ + ret = deflate(&png_ptr->zstream, Z_SYNC_FLUSH); + wrote_IDAT = 0; + + /* Check for compression errors */ + if (ret != Z_OK) + { + if (png_ptr->zstream.msg != NULL) + png_error(png_ptr, png_ptr->zstream.msg); + else + png_error(png_ptr, "zlib error"); + } + + if (!(png_ptr->zstream.avail_out)) + { + /* Write the IDAT and reset the zlib output buffer */ + png_write_IDAT(png_ptr, png_ptr->zbuf, + png_ptr->zbuf_size); + png_ptr->zstream.next_out = png_ptr->zbuf; + png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size; + wrote_IDAT = 1; + } + } while(wrote_IDAT == 1); + + /* If there is any data left to be output, write it into a new IDAT */ + if (png_ptr->zbuf_size != png_ptr->zstream.avail_out) + { + /* Write the IDAT and reset the zlib output buffer */ + png_write_IDAT(png_ptr, png_ptr->zbuf, + png_ptr->zbuf_size - png_ptr->zstream.avail_out); + png_ptr->zstream.next_out = png_ptr->zbuf; + png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size; + } + png_ptr->flush_rows = 0; + png_flush(png_ptr); +} +#endif /* PNG_WRITE_FLUSH_SUPPORTED */ + +/* Free all memory used by the write */ +void PNGAPI +png_destroy_write_struct(png_structpp png_ptr_ptr, png_infopp info_ptr_ptr) +{ + png_structp png_ptr = NULL; + png_infop info_ptr = NULL; +#ifdef PNG_USER_MEM_SUPPORTED + png_free_ptr free_fn = NULL; + png_voidp mem_ptr = NULL; +#endif + + png_debug(1, "in png_destroy_write_struct"); + + if (png_ptr_ptr != NULL) + { + png_ptr = *png_ptr_ptr; +#ifdef PNG_USER_MEM_SUPPORTED + free_fn = png_ptr->free_fn; + mem_ptr = png_ptr->mem_ptr; +#endif + } + +#ifdef PNG_USER_MEM_SUPPORTED + if (png_ptr != NULL) + { + free_fn = png_ptr->free_fn; + mem_ptr = png_ptr->mem_ptr; + } +#endif + + if (info_ptr_ptr != NULL) + info_ptr = *info_ptr_ptr; + + if (info_ptr != NULL) + { + if (png_ptr != NULL) + { + png_free_data(png_ptr, info_ptr, PNG_FREE_ALL, -1); + +#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED + if (png_ptr->num_chunk_list) + { + png_free(png_ptr, png_ptr->chunk_list); + png_ptr->num_chunk_list = 0; + } +#endif + } + +#ifdef PNG_USER_MEM_SUPPORTED + png_destroy_struct_2((png_voidp)info_ptr, (png_free_ptr)free_fn, + (png_voidp)mem_ptr); +#else + png_destroy_struct((png_voidp)info_ptr); +#endif + *info_ptr_ptr = NULL; + } + + if (png_ptr != NULL) + { + png_write_destroy(png_ptr); +#ifdef PNG_USER_MEM_SUPPORTED + png_destroy_struct_2((png_voidp)png_ptr, (png_free_ptr)free_fn, + (png_voidp)mem_ptr); +#else + png_destroy_struct((png_voidp)png_ptr); +#endif + *png_ptr_ptr = NULL; + } +} + + +/* Free any memory used in png_ptr struct (old method) */ +void /* PRIVATE */ +png_write_destroy(png_structp png_ptr) +{ +#ifdef PNG_SETJMP_SUPPORTED + jmp_buf tmp_jmp; /* Save jump buffer */ +#endif + png_error_ptr error_fn; + png_error_ptr warning_fn; + png_voidp error_ptr; +#ifdef PNG_USER_MEM_SUPPORTED + png_free_ptr free_fn; +#endif + + png_debug(1, "in png_write_destroy"); + + /* Free any memory zlib uses */ + deflateEnd(&png_ptr->zstream); + + /* Free our memory. png_free checks NULL for us. */ + png_free(png_ptr, png_ptr->zbuf); + png_free(png_ptr, png_ptr->row_buf); +#ifdef PNG_WRITE_FILTER_SUPPORTED + png_free(png_ptr, png_ptr->prev_row); + png_free(png_ptr, png_ptr->sub_row); + png_free(png_ptr, png_ptr->up_row); + png_free(png_ptr, png_ptr->avg_row); + png_free(png_ptr, png_ptr->paeth_row); +#endif + +#ifdef PNG_TIME_RFC1123_SUPPORTED + png_free(png_ptr, png_ptr->time_buffer); +#endif + +#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED + png_free(png_ptr, png_ptr->prev_filters); + png_free(png_ptr, png_ptr->filter_weights); + png_free(png_ptr, png_ptr->inv_filter_weights); + png_free(png_ptr, png_ptr->filter_costs); + png_free(png_ptr, png_ptr->inv_filter_costs); +#endif + +#ifdef PNG_SETJMP_SUPPORTED + /* Reset structure */ + png_memcpy(tmp_jmp, png_ptr->jmpbuf, png_sizeof(jmp_buf)); +#endif + + error_fn = png_ptr->error_fn; + warning_fn = png_ptr->warning_fn; + error_ptr = png_ptr->error_ptr; +#ifdef PNG_USER_MEM_SUPPORTED + free_fn = png_ptr->free_fn; +#endif + + png_memset(png_ptr, 0, png_sizeof(png_struct)); + + png_ptr->error_fn = error_fn; + png_ptr->warning_fn = warning_fn; + png_ptr->error_ptr = error_ptr; +#ifdef PNG_USER_MEM_SUPPORTED + png_ptr->free_fn = free_fn; +#endif + +#ifdef PNG_SETJMP_SUPPORTED + png_memcpy(png_ptr->jmpbuf, tmp_jmp, png_sizeof(jmp_buf)); +#endif +} + +/* Allow the application to select one or more row filters to use. */ +void PNGAPI +png_set_filter(png_structp png_ptr, int method, int filters) +{ + png_debug(1, "in png_set_filter"); + + if (png_ptr == NULL) + return; +#ifdef PNG_MNG_FEATURES_SUPPORTED + if ((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) && + (method == PNG_INTRAPIXEL_DIFFERENCING)) + method = PNG_FILTER_TYPE_BASE; +#endif + if (method == PNG_FILTER_TYPE_BASE) + { + switch (filters & (PNG_ALL_FILTERS | 0x07)) + { +#ifdef PNG_WRITE_FILTER_SUPPORTED + case 5: + case 6: + case 7: png_warning(png_ptr, "Unknown row filter for method 0"); +#endif /* PNG_WRITE_FILTER_SUPPORTED */ + case PNG_FILTER_VALUE_NONE: + png_ptr->do_filter = PNG_FILTER_NONE; break; +#ifdef PNG_WRITE_FILTER_SUPPORTED + case PNG_FILTER_VALUE_SUB: + png_ptr->do_filter = PNG_FILTER_SUB; break; + case PNG_FILTER_VALUE_UP: + png_ptr->do_filter = PNG_FILTER_UP; break; + case PNG_FILTER_VALUE_AVG: + png_ptr->do_filter = PNG_FILTER_AVG; break; + case PNG_FILTER_VALUE_PAETH: + png_ptr->do_filter = PNG_FILTER_PAETH; break; + default: png_ptr->do_filter = (png_byte)filters; break; +#else + default: png_warning(png_ptr, "Unknown row filter for method 0"); +#endif /* PNG_WRITE_FILTER_SUPPORTED */ + } + + /* If we have allocated the row_buf, this means we have already started + * with the image and we should have allocated all of the filter buffers + * that have been selected. If prev_row isn't already allocated, then + * it is too late to start using the filters that need it, since we + * will be missing the data in the previous row. If an application + * wants to start and stop using particular filters during compression, + * it should start out with all of the filters, and then add and + * remove them after the start of compression. + */ + if (png_ptr->row_buf != NULL) + { +#ifdef PNG_WRITE_FILTER_SUPPORTED + if ((png_ptr->do_filter & PNG_FILTER_SUB) && png_ptr->sub_row == NULL) + { + png_ptr->sub_row = (png_bytep)png_malloc(png_ptr, + (png_ptr->rowbytes + 1)); + png_ptr->sub_row[0] = PNG_FILTER_VALUE_SUB; + } + + if ((png_ptr->do_filter & PNG_FILTER_UP) && png_ptr->up_row == NULL) + { + if (png_ptr->prev_row == NULL) + { + png_warning(png_ptr, "Can't add Up filter after starting"); + png_ptr->do_filter &= ~PNG_FILTER_UP; + } + else + { + png_ptr->up_row = (png_bytep)png_malloc(png_ptr, + (png_ptr->rowbytes + 1)); + png_ptr->up_row[0] = PNG_FILTER_VALUE_UP; + } + } + + if ((png_ptr->do_filter & PNG_FILTER_AVG) && png_ptr->avg_row == NULL) + { + if (png_ptr->prev_row == NULL) + { + png_warning(png_ptr, "Can't add Average filter after starting"); + png_ptr->do_filter &= ~PNG_FILTER_AVG; + } + else + { + png_ptr->avg_row = (png_bytep)png_malloc(png_ptr, + (png_ptr->rowbytes + 1)); + png_ptr->avg_row[0] = PNG_FILTER_VALUE_AVG; + } + } + + if ((png_ptr->do_filter & PNG_FILTER_PAETH) && + png_ptr->paeth_row == NULL) + { + if (png_ptr->prev_row == NULL) + { + png_warning(png_ptr, "Can't add Paeth filter after starting"); + png_ptr->do_filter &= (png_byte)(~PNG_FILTER_PAETH); + } + else + { + png_ptr->paeth_row = (png_bytep)png_malloc(png_ptr, + (png_ptr->rowbytes + 1)); + png_ptr->paeth_row[0] = PNG_FILTER_VALUE_PAETH; + } + } + + if (png_ptr->do_filter == PNG_NO_FILTERS) +#endif /* PNG_WRITE_FILTER_SUPPORTED */ + png_ptr->do_filter = PNG_FILTER_NONE; + } + } + else + png_error(png_ptr, "Unknown custom filter method"); +} + +/* This allows us to influence the way in which libpng chooses the "best" + * filter for the current scanline. While the "minimum-sum-of-absolute- + * differences metric is relatively fast and effective, there is some + * question as to whether it can be improved upon by trying to keep the + * filtered data going to zlib more consistent, hopefully resulting in + * better compression. + */ +#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED /* GRR 970116 */ +void PNGAPI +png_set_filter_heuristics(png_structp png_ptr, int heuristic_method, + int num_weights, png_doublep filter_weights, + png_doublep filter_costs) +{ + int i; + + png_debug(1, "in png_set_filter_heuristics"); + + if (png_ptr == NULL) + return; + if (heuristic_method >= PNG_FILTER_HEURISTIC_LAST) + { + png_warning(png_ptr, "Unknown filter heuristic method"); + return; + } + + if (heuristic_method == PNG_FILTER_HEURISTIC_DEFAULT) + { + heuristic_method = PNG_FILTER_HEURISTIC_UNWEIGHTED; + } + + if (num_weights < 0 || filter_weights == NULL || + heuristic_method == PNG_FILTER_HEURISTIC_UNWEIGHTED) + { + num_weights = 0; + } + + png_ptr->num_prev_filters = (png_byte)num_weights; + png_ptr->heuristic_method = (png_byte)heuristic_method; + + if (num_weights > 0) + { + if (png_ptr->prev_filters == NULL) + { + png_ptr->prev_filters = (png_bytep)png_malloc(png_ptr, + (png_uint_32)(png_sizeof(png_byte) * num_weights)); + + /* To make sure that the weighting starts out fairly */ + for (i = 0; i < num_weights; i++) + { + png_ptr->prev_filters[i] = 255; + } + } + + if (png_ptr->filter_weights == NULL) + { + png_ptr->filter_weights = (png_uint_16p)png_malloc(png_ptr, + (png_uint_32)(png_sizeof(png_uint_16) * num_weights)); + + png_ptr->inv_filter_weights = (png_uint_16p)png_malloc(png_ptr, + (png_uint_32)(png_sizeof(png_uint_16) * num_weights)); + for (i = 0; i < num_weights; i++) + { + png_ptr->inv_filter_weights[i] = + png_ptr->filter_weights[i] = PNG_WEIGHT_FACTOR; + } + } + + for (i = 0; i < num_weights; i++) + { + if (filter_weights[i] < 0.0) + { + png_ptr->inv_filter_weights[i] = + png_ptr->filter_weights[i] = PNG_WEIGHT_FACTOR; + } + else + { + png_ptr->inv_filter_weights[i] = + (png_uint_16)((double)PNG_WEIGHT_FACTOR*filter_weights[i]+0.5); + png_ptr->filter_weights[i] = + (png_uint_16)((double)PNG_WEIGHT_FACTOR/filter_weights[i]+0.5); + } + } + } + + /* If, in the future, there are other filter methods, this would + * need to be based on png_ptr->filter. + */ + if (png_ptr->filter_costs == NULL) + { + png_ptr->filter_costs = (png_uint_16p)png_malloc(png_ptr, + (png_uint_32)(png_sizeof(png_uint_16) * PNG_FILTER_VALUE_LAST)); + + png_ptr->inv_filter_costs = (png_uint_16p)png_malloc(png_ptr, + (png_uint_32)(png_sizeof(png_uint_16) * PNG_FILTER_VALUE_LAST)); + + for (i = 0; i < PNG_FILTER_VALUE_LAST; i++) + { + png_ptr->inv_filter_costs[i] = + png_ptr->filter_costs[i] = PNG_COST_FACTOR; + } + } + + /* Here is where we set the relative costs of the different filters. We + * should take the desired compression level into account when setting + * the costs, so that Paeth, for instance, has a high relative cost at low + * compression levels, while it has a lower relative cost at higher + * compression settings. The filter types are in order of increasing + * relative cost, so it would be possible to do this with an algorithm. + */ + for (i = 0; i < PNG_FILTER_VALUE_LAST; i++) + { + if (filter_costs == NULL || filter_costs[i] < 0.0) + { + png_ptr->inv_filter_costs[i] = + png_ptr->filter_costs[i] = PNG_COST_FACTOR; + } + else if (filter_costs[i] >= 1.0) + { + png_ptr->inv_filter_costs[i] = + (png_uint_16)((double)PNG_COST_FACTOR / filter_costs[i] + 0.5); + png_ptr->filter_costs[i] = + (png_uint_16)((double)PNG_COST_FACTOR * filter_costs[i] + 0.5); + } + } +} +#endif /* PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */ + +void PNGAPI +png_set_compression_level(png_structp png_ptr, int level) +{ + png_debug(1, "in png_set_compression_level"); + + if (png_ptr == NULL) + return; + png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_LEVEL; + png_ptr->zlib_level = level; +} + +void PNGAPI +png_set_compression_mem_level(png_structp png_ptr, int mem_level) +{ + png_debug(1, "in png_set_compression_mem_level"); + + if (png_ptr == NULL) + return; + png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_MEM_LEVEL; + png_ptr->zlib_mem_level = mem_level; +} + +void PNGAPI +png_set_compression_strategy(png_structp png_ptr, int strategy) +{ + png_debug(1, "in png_set_compression_strategy"); + + if (png_ptr == NULL) + return; + png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_STRATEGY; + png_ptr->zlib_strategy = strategy; +} + +void PNGAPI +png_set_compression_window_bits(png_structp png_ptr, int window_bits) +{ + if (png_ptr == NULL) + return; + if (window_bits > 15) + png_warning(png_ptr, "Only compression windows <= 32k supported by PNG"); + else if (window_bits < 8) + png_warning(png_ptr, "Only compression windows >= 256 supported by PNG"); +#ifndef WBITS_8_OK + /* Avoid libpng bug with 256-byte windows */ + if (window_bits == 8) + { + png_warning(png_ptr, "Compression window is being reset to 512"); + window_bits = 9; + } +#endif + png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_WINDOW_BITS; + png_ptr->zlib_window_bits = window_bits; +} + +void PNGAPI +png_set_compression_method(png_structp png_ptr, int method) +{ + png_debug(1, "in png_set_compression_method"); + + if (png_ptr == NULL) + return; + if (method != 8) + png_warning(png_ptr, "Only compression method 8 is supported by PNG"); + png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_METHOD; + png_ptr->zlib_method = method; +} + +void PNGAPI +png_set_write_status_fn(png_structp png_ptr, png_write_status_ptr write_row_fn) +{ + if (png_ptr == NULL) + return; + png_ptr->write_row_fn = write_row_fn; +} + +#ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED +void PNGAPI +png_set_write_user_transform_fn(png_structp png_ptr, png_user_transform_ptr + write_user_transform_fn) +{ + png_debug(1, "in png_set_write_user_transform_fn"); + + if (png_ptr == NULL) + return; + png_ptr->transformations |= PNG_USER_TRANSFORM; + png_ptr->write_user_transform_fn = write_user_transform_fn; +} +#endif + + +#ifdef PNG_INFO_IMAGE_SUPPORTED +void PNGAPI +png_write_png(png_structp png_ptr, png_infop info_ptr, + int transforms, voidp params) +{ + if (png_ptr == NULL || info_ptr == NULL) + return; + + /* Write the file header information. */ + png_write_info(png_ptr, info_ptr); + + /* ------ these transformations don't touch the info structure ------- */ + +#ifdef PNG_WRITE_INVERT_SUPPORTED + /* Invert monochrome pixels */ + if (transforms & PNG_TRANSFORM_INVERT_MONO) + png_set_invert_mono(png_ptr); +#endif + +#ifdef PNG_WRITE_SHIFT_SUPPORTED + /* Shift the pixels up to a legal bit depth and fill in + * as appropriate to correctly scale the image. + */ + if ((transforms & PNG_TRANSFORM_SHIFT) + && (info_ptr->valid & PNG_INFO_sBIT)) + png_set_shift(png_ptr, &info_ptr->sig_bit); +#endif + +#ifdef PNG_WRITE_PACK_SUPPORTED + /* Pack pixels into bytes */ + if (transforms & PNG_TRANSFORM_PACKING) + png_set_packing(png_ptr); +#endif + +#ifdef PNG_WRITE_SWAP_ALPHA_SUPPORTED + /* Swap location of alpha bytes from ARGB to RGBA */ + if (transforms & PNG_TRANSFORM_SWAP_ALPHA) + png_set_swap_alpha(png_ptr); +#endif + +#ifdef PNG_WRITE_FILLER_SUPPORTED + /* Pack XRGB/RGBX/ARGB/RGBA into * RGB (4 channels -> 3 channels) */ + if (transforms & PNG_TRANSFORM_STRIP_FILLER_AFTER) + png_set_filler(png_ptr, 0, PNG_FILLER_AFTER); + else if (transforms & PNG_TRANSFORM_STRIP_FILLER_BEFORE) + png_set_filler(png_ptr, 0, PNG_FILLER_BEFORE); +#endif + +#ifdef PNG_WRITE_BGR_SUPPORTED + /* Flip BGR pixels to RGB */ + if (transforms & PNG_TRANSFORM_BGR) + png_set_bgr(png_ptr); +#endif + +#ifdef PNG_WRITE_SWAP_SUPPORTED + /* Swap bytes of 16-bit files to most significant byte first */ + if (transforms & PNG_TRANSFORM_SWAP_ENDIAN) + png_set_swap(png_ptr); +#endif + +#ifdef PNG_WRITE_PACKSWAP_SUPPORTED + /* Swap bits of 1, 2, 4 bit packed pixel formats */ + if (transforms & PNG_TRANSFORM_PACKSWAP) + png_set_packswap(png_ptr); +#endif + +#ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED + /* Invert the alpha channel from opacity to transparency */ + if (transforms & PNG_TRANSFORM_INVERT_ALPHA) + png_set_invert_alpha(png_ptr); +#endif + + /* ----------------------- end of transformations ------------------- */ + + /* Write the bits */ + if (info_ptr->valid & PNG_INFO_IDAT) + png_write_image(png_ptr, info_ptr->row_pointers); + + /* It is REQUIRED to call this to finish writing the rest of the file */ + png_write_end(png_ptr, info_ptr); + + transforms = transforms; /* Quiet compiler warnings */ + params = params; +} +#endif +#endif /* PNG_WRITE_SUPPORTED */ diff --git a/libpng/pngwtran.c b/libpng/pngwtran.c new file mode 100644 index 0000000..070caa5 --- /dev/null +++ b/libpng/pngwtran.c @@ -0,0 +1,566 @@ + +/* pngwtran.c - transforms the data in a row for PNG writers + * + * Last changed in libpng 1.4.1 [February 25, 2010] + * Copyright (c) 1998-2010 Glenn Randers-Pehrson + * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) + * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) + * + * This code is released under the libpng license. + * For conditions of distribution and use, see the disclaimer + * and license in png.h + */ + +#define PNG_NO_PEDANTIC_WARNINGS +#include "png.h" +#ifdef PNG_WRITE_SUPPORTED +#include "pngpriv.h" + +/* Transform the data according to the user's wishes. The order of + * transformations is significant. + */ +void /* PRIVATE */ +png_do_write_transformations(png_structp png_ptr) +{ + png_debug(1, "in png_do_write_transformations"); + + if (png_ptr == NULL) + return; + +#ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED + if (png_ptr->transformations & PNG_USER_TRANSFORM) + if (png_ptr->write_user_transform_fn != NULL) + (*(png_ptr->write_user_transform_fn)) /* User write transform + function */ + (png_ptr, /* png_ptr */ + &(png_ptr->row_info), /* row_info: */ + /* png_uint_32 width; width of row */ + /* png_uint_32 rowbytes; number of bytes in row */ + /* png_byte color_type; color type of pixels */ + /* png_byte bit_depth; bit depth of samples */ + /* png_byte channels; number of channels (1-4) */ + /* png_byte pixel_depth; bits per pixel (depth*channels) */ + png_ptr->row_buf + 1); /* start of pixel data for row */ +#endif +#ifdef PNG_WRITE_FILLER_SUPPORTED + if (png_ptr->transformations & PNG_FILLER) + png_do_strip_filler(&(png_ptr->row_info), png_ptr->row_buf + 1, + png_ptr->flags); +#endif +#ifdef PNG_WRITE_PACKSWAP_SUPPORTED + if (png_ptr->transformations & PNG_PACKSWAP) + png_do_packswap(&(png_ptr->row_info), png_ptr->row_buf + 1); +#endif +#ifdef PNG_WRITE_PACK_SUPPORTED + if (png_ptr->transformations & PNG_PACK) + png_do_pack(&(png_ptr->row_info), png_ptr->row_buf + 1, + (png_uint_32)png_ptr->bit_depth); +#endif +#ifdef PNG_WRITE_SWAP_SUPPORTED + if (png_ptr->transformations & PNG_SWAP_BYTES) + png_do_swap(&(png_ptr->row_info), png_ptr->row_buf + 1); +#endif +#ifdef PNG_WRITE_SHIFT_SUPPORTED + if (png_ptr->transformations & PNG_SHIFT) + png_do_shift(&(png_ptr->row_info), png_ptr->row_buf + 1, + &(png_ptr->shift)); +#endif +#ifdef PNG_WRITE_SWAP_ALPHA_SUPPORTED + if (png_ptr->transformations & PNG_SWAP_ALPHA) + png_do_write_swap_alpha(&(png_ptr->row_info), png_ptr->row_buf + 1); +#endif +#ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED + if (png_ptr->transformations & PNG_INVERT_ALPHA) + png_do_write_invert_alpha(&(png_ptr->row_info), png_ptr->row_buf + 1); +#endif +#ifdef PNG_WRITE_BGR_SUPPORTED + if (png_ptr->transformations & PNG_BGR) + png_do_bgr(&(png_ptr->row_info), png_ptr->row_buf + 1); +#endif +#ifdef PNG_WRITE_INVERT_SUPPORTED + if (png_ptr->transformations & PNG_INVERT_MONO) + png_do_invert(&(png_ptr->row_info), png_ptr->row_buf + 1); +#endif +} + +#ifdef PNG_WRITE_PACK_SUPPORTED +/* Pack pixels into bytes. Pass the true bit depth in bit_depth. The + * row_info bit depth should be 8 (one pixel per byte). The channels + * should be 1 (this only happens on grayscale and paletted images). + */ +void /* PRIVATE */ +png_do_pack(png_row_infop row_info, png_bytep row, png_uint_32 bit_depth) +{ + png_debug(1, "in png_do_pack"); + + if (row_info->bit_depth == 8 && + row_info->channels == 1) + { + switch ((int)bit_depth) + { + case 1: + { + png_bytep sp, dp; + int mask, v; + png_uint_32 i; + png_uint_32 row_width = row_info->width; + + sp = row; + dp = row; + mask = 0x80; + v = 0; + + for (i = 0; i < row_width; i++) + { + if (*sp != 0) + v |= mask; + sp++; + if (mask > 1) + mask >>= 1; + else + { + mask = 0x80; + *dp = (png_byte)v; + dp++; + v = 0; + } + } + if (mask != 0x80) + *dp = (png_byte)v; + break; + } + case 2: + { + png_bytep sp, dp; + int shift, v; + png_uint_32 i; + png_uint_32 row_width = row_info->width; + + sp = row; + dp = row; + shift = 6; + v = 0; + for (i = 0; i < row_width; i++) + { + png_byte value; + + value = (png_byte)(*sp & 0x03); + v |= (value << shift); + if (shift == 0) + { + shift = 6; + *dp = (png_byte)v; + dp++; + v = 0; + } + else + shift -= 2; + sp++; + } + if (shift != 6) + *dp = (png_byte)v; + break; + } + case 4: + { + png_bytep sp, dp; + int shift, v; + png_uint_32 i; + png_uint_32 row_width = row_info->width; + + sp = row; + dp = row; + shift = 4; + v = 0; + for (i = 0; i < row_width; i++) + { + png_byte value; + + value = (png_byte)(*sp & 0x0f); + v |= (value << shift); + + if (shift == 0) + { + shift = 4; + *dp = (png_byte)v; + dp++; + v = 0; + } + else + shift -= 4; + + sp++; + } + if (shift != 4) + *dp = (png_byte)v; + break; + } + } + row_info->bit_depth = (png_byte)bit_depth; + row_info->pixel_depth = (png_byte)(bit_depth * row_info->channels); + row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth, + row_info->width); + } +} +#endif + +#ifdef PNG_WRITE_SHIFT_SUPPORTED +/* Shift pixel values to take advantage of whole range. Pass the + * true number of bits in bit_depth. The row should be packed + * according to row_info->bit_depth. Thus, if you had a row of + * bit depth 4, but the pixels only had values from 0 to 7, you + * would pass 3 as bit_depth, and this routine would translate the + * data to 0 to 15. + */ +void /* PRIVATE */ +png_do_shift(png_row_infop row_info, png_bytep row, png_color_8p bit_depth) +{ + png_debug(1, "in png_do_shift"); + + if ( + row_info->color_type != PNG_COLOR_TYPE_PALETTE) + { + int shift_start[4], shift_dec[4]; + int channels = 0; + + if (row_info->color_type & PNG_COLOR_MASK_COLOR) + { + shift_start[channels] = row_info->bit_depth - bit_depth->red; + shift_dec[channels] = bit_depth->red; + channels++; + shift_start[channels] = row_info->bit_depth - bit_depth->green; + shift_dec[channels] = bit_depth->green; + channels++; + shift_start[channels] = row_info->bit_depth - bit_depth->blue; + shift_dec[channels] = bit_depth->blue; + channels++; + } + else + { + shift_start[channels] = row_info->bit_depth - bit_depth->gray; + shift_dec[channels] = bit_depth->gray; + channels++; + } + if (row_info->color_type & PNG_COLOR_MASK_ALPHA) + { + shift_start[channels] = row_info->bit_depth - bit_depth->alpha; + shift_dec[channels] = bit_depth->alpha; + channels++; + } + + /* With low row depths, could only be grayscale, so one channel */ + if (row_info->bit_depth < 8) + { + png_bytep bp = row; + png_uint_32 i; + png_byte mask; + png_uint_32 row_bytes = row_info->rowbytes; + + if (bit_depth->gray == 1 && row_info->bit_depth == 2) + mask = 0x55; + else if (row_info->bit_depth == 4 && bit_depth->gray == 3) + mask = 0x11; + else + mask = 0xff; + + for (i = 0; i < row_bytes; i++, bp++) + { + png_uint_16 v; + int j; + + v = *bp; + *bp = 0; + for (j = shift_start[0]; j > -shift_dec[0]; j -= shift_dec[0]) + { + if (j > 0) + *bp |= (png_byte)((v << j) & 0xff); + else + *bp |= (png_byte)((v >> (-j)) & mask); + } + } + } + else if (row_info->bit_depth == 8) + { + png_bytep bp = row; + png_uint_32 i; + png_uint_32 istop = channels * row_info->width; + + for (i = 0; i < istop; i++, bp++) + { + + png_uint_16 v; + int j; + int c = (int)(i%channels); + + v = *bp; + *bp = 0; + for (j = shift_start[c]; j > -shift_dec[c]; j -= shift_dec[c]) + { + if (j > 0) + *bp |= (png_byte)((v << j) & 0xff); + else + *bp |= (png_byte)((v >> (-j)) & 0xff); + } + } + } + else + { + png_bytep bp; + png_uint_32 i; + png_uint_32 istop = channels * row_info->width; + + for (bp = row, i = 0; i < istop; i++) + { + int c = (int)(i%channels); + png_uint_16 value, v; + int j; + + v = (png_uint_16)(((png_uint_16)(*bp) << 8) + *(bp + 1)); + value = 0; + for (j = shift_start[c]; j > -shift_dec[c]; j -= shift_dec[c]) + { + if (j > 0) + value |= (png_uint_16)((v << j) & (png_uint_16)0xffff); + else + value |= (png_uint_16)((v >> (-j)) & (png_uint_16)0xffff); + } + *bp++ = (png_byte)(value >> 8); + *bp++ = (png_byte)(value & 0xff); + } + } + } +} +#endif + +#ifdef PNG_WRITE_SWAP_ALPHA_SUPPORTED +void /* PRIVATE */ +png_do_write_swap_alpha(png_row_infop row_info, png_bytep row) +{ + png_debug(1, "in png_do_write_swap_alpha"); + + { + if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) + { + /* This converts from ARGB to RGBA */ + if (row_info->bit_depth == 8) + { + png_bytep sp, dp; + png_uint_32 i; + png_uint_32 row_width = row_info->width; + for (i = 0, sp = dp = row; i < row_width; i++) + { + png_byte save = *(sp++); + *(dp++) = *(sp++); + *(dp++) = *(sp++); + *(dp++) = *(sp++); + *(dp++) = save; + } + } + /* This converts from AARRGGBB to RRGGBBAA */ + else + { + png_bytep sp, dp; + png_uint_32 i; + png_uint_32 row_width = row_info->width; + + for (i = 0, sp = dp = row; i < row_width; i++) + { + png_byte save[2]; + save[0] = *(sp++); + save[1] = *(sp++); + *(dp++) = *(sp++); + *(dp++) = *(sp++); + *(dp++) = *(sp++); + *(dp++) = *(sp++); + *(dp++) = *(sp++); + *(dp++) = *(sp++); + *(dp++) = save[0]; + *(dp++) = save[1]; + } + } + } + else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA) + { + /* This converts from AG to GA */ + if (row_info->bit_depth == 8) + { + png_bytep sp, dp; + png_uint_32 i; + png_uint_32 row_width = row_info->width; + + for (i = 0, sp = dp = row; i < row_width; i++) + { + png_byte save = *(sp++); + *(dp++) = *(sp++); + *(dp++) = save; + } + } + /* This converts from AAGG to GGAA */ + else + { + png_bytep sp, dp; + png_uint_32 i; + png_uint_32 row_width = row_info->width; + + for (i = 0, sp = dp = row; i < row_width; i++) + { + png_byte save[2]; + save[0] = *(sp++); + save[1] = *(sp++); + *(dp++) = *(sp++); + *(dp++) = *(sp++); + *(dp++) = save[0]; + *(dp++) = save[1]; + } + } + } + } +} +#endif + +#ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED +void /* PRIVATE */ +png_do_write_invert_alpha(png_row_infop row_info, png_bytep row) +{ + png_debug(1, "in png_do_write_invert_alpha"); + + { + if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) + { + /* This inverts the alpha channel in RGBA */ + if (row_info->bit_depth == 8) + { + png_bytep sp, dp; + png_uint_32 i; + png_uint_32 row_width = row_info->width; + for (i = 0, sp = dp = row; i < row_width; i++) + { + /* Does nothing + *(dp++) = *(sp++); + *(dp++) = *(sp++); + *(dp++) = *(sp++); + */ + sp+=3; dp = sp; + *(dp++) = (png_byte)(255 - *(sp++)); + } + } + /* This inverts the alpha channel in RRGGBBAA */ + else + { + png_bytep sp, dp; + png_uint_32 i; + png_uint_32 row_width = row_info->width; + + for (i = 0, sp = dp = row; i < row_width; i++) + { + /* Does nothing + *(dp++) = *(sp++); + *(dp++) = *(sp++); + *(dp++) = *(sp++); + *(dp++) = *(sp++); + *(dp++) = *(sp++); + *(dp++) = *(sp++); + */ + sp+=6; dp = sp; + *(dp++) = (png_byte)(255 - *(sp++)); + *(dp++) = (png_byte)(255 - *(sp++)); + } + } + } + else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA) + { + /* This inverts the alpha channel in GA */ + if (row_info->bit_depth == 8) + { + png_bytep sp, dp; + png_uint_32 i; + png_uint_32 row_width = row_info->width; + + for (i = 0, sp = dp = row; i < row_width; i++) + { + *(dp++) = *(sp++); + *(dp++) = (png_byte)(255 - *(sp++)); + } + } + /* This inverts the alpha channel in GGAA */ + else + { + png_bytep sp, dp; + png_uint_32 i; + png_uint_32 row_width = row_info->width; + + for (i = 0, sp = dp = row; i < row_width; i++) + { + /* Does nothing + *(dp++) = *(sp++); + *(dp++) = *(sp++); + */ + sp+=2; dp = sp; + *(dp++) = (png_byte)(255 - *(sp++)); + *(dp++) = (png_byte)(255 - *(sp++)); + } + } + } + } +} +#endif + +#ifdef PNG_MNG_FEATURES_SUPPORTED +/* Undoes intrapixel differencing */ +void /* PRIVATE */ +png_do_write_intrapixel(png_row_infop row_info, png_bytep row) +{ + png_debug(1, "in png_do_write_intrapixel"); + + if ( + (row_info->color_type & PNG_COLOR_MASK_COLOR)) + { + int bytes_per_pixel; + png_uint_32 row_width = row_info->width; + if (row_info->bit_depth == 8) + { + png_bytep rp; + png_uint_32 i; + + if (row_info->color_type == PNG_COLOR_TYPE_RGB) + bytes_per_pixel = 3; + else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) + bytes_per_pixel = 4; + else + return; + + for (i = 0, rp = row; i < row_width; i++, rp += bytes_per_pixel) + { + *(rp) = (png_byte)((*rp - *(rp+1))&0xff); + *(rp+2) = (png_byte)((*(rp+2) - *(rp+1))&0xff); + } + } + else if (row_info->bit_depth == 16) + { + png_bytep rp; + png_uint_32 i; + + if (row_info->color_type == PNG_COLOR_TYPE_RGB) + bytes_per_pixel = 6; + else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) + bytes_per_pixel = 8; + else + return; + + for (i = 0, rp = row; i < row_width; i++, rp += bytes_per_pixel) + { + png_uint_32 s0 = (*(rp ) << 8) | *(rp+1); + png_uint_32 s1 = (*(rp+2) << 8) | *(rp+3); + png_uint_32 s2 = (*(rp+4) << 8) | *(rp+5); + png_uint_32 red = (png_uint_32)((s0 - s1) & 0xffffL); + png_uint_32 blue = (png_uint_32)((s2 - s1) & 0xffffL); + *(rp ) = (png_byte)((red >> 8) & 0xff); + *(rp+1) = (png_byte)(red & 0xff); + *(rp+4) = (png_byte)((blue >> 8) & 0xff); + *(rp+5) = (png_byte)(blue & 0xff); + } + } + } +} +#endif /* PNG_MNG_FEATURES_SUPPORTED */ +#endif /* PNG_WRITE_SUPPORTED */ diff --git a/libpng/pngwutil.c b/libpng/pngwutil.c new file mode 100644 index 0000000..19feb1d --- /dev/null +++ b/libpng/pngwutil.c @@ -0,0 +1,2786 @@ + +/* pngwutil.c - utilities to write a PNG file + * + * Last changed in libpng 1.4.1 [February 25, 2010] + * Copyright (c) 1998-2010 Glenn Randers-Pehrson + * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) + * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) + * + * This code is released under the libpng license. + * For conditions of distribution and use, see the disclaimer + * and license in png.h + */ + +#define PNG_NO_PEDANTIC_WARNINGS +#include "png.h" +#ifdef PNG_WRITE_SUPPORTED +#include "pngpriv.h" + +/* Place a 32-bit number into a buffer in PNG byte order. We work + * with unsigned numbers for convenience, although one supported + * ancillary chunk uses signed (two's complement) numbers. + */ +void PNGAPI +png_save_uint_32(png_bytep buf, png_uint_32 i) +{ + buf[0] = (png_byte)((i >> 24) & 0xff); + buf[1] = (png_byte)((i >> 16) & 0xff); + buf[2] = (png_byte)((i >> 8) & 0xff); + buf[3] = (png_byte)(i & 0xff); +} + +#ifdef PNG_SAVE_INT_32_SUPPORTED +/* The png_save_int_32 function assumes integers are stored in two's + * complement format. If this isn't the case, then this routine needs to + * be modified to write data in two's complement format. + */ +void PNGAPI +png_save_int_32(png_bytep buf, png_int_32 i) +{ + buf[0] = (png_byte)((i >> 24) & 0xff); + buf[1] = (png_byte)((i >> 16) & 0xff); + buf[2] = (png_byte)((i >> 8) & 0xff); + buf[3] = (png_byte)(i & 0xff); +} +#endif + +/* Place a 16-bit number into a buffer in PNG byte order. + * The parameter is declared unsigned int, not png_uint_16, + * just to avoid potential problems on pre-ANSI C compilers. + */ +void PNGAPI +png_save_uint_16(png_bytep buf, unsigned int i) +{ + buf[0] = (png_byte)((i >> 8) & 0xff); + buf[1] = (png_byte)(i & 0xff); +} + +/* Simple function to write the signature. If we have already written + * the magic bytes of the signature, or more likely, the PNG stream is + * being embedded into another stream and doesn't need its own signature, + * we should call png_set_sig_bytes() to tell libpng how many of the + * bytes have already been written. + */ +void PNGAPI +png_write_sig(png_structp png_ptr) +{ + png_byte png_signature[8] = {137, 80, 78, 71, 13, 10, 26, 10}; + +#ifdef PNG_IO_STATE_SUPPORTED + /* Inform the I/O callback that the signature is being written */ + png_ptr->io_state = PNG_IO_WRITING | PNG_IO_SIGNATURE; +#endif + + /* Write the rest of the 8 byte signature */ + png_write_data(png_ptr, &png_signature[png_ptr->sig_bytes], + (png_size_t)(8 - png_ptr->sig_bytes)); + if (png_ptr->sig_bytes < 3) + png_ptr->mode |= PNG_HAVE_PNG_SIGNATURE; +} + +/* Write a PNG chunk all at once. The type is an array of ASCII characters + * representing the chunk name. The array must be at least 4 bytes in + * length, and does not need to be null terminated. To be safe, pass the + * pre-defined chunk names here, and if you need a new one, define it + * where the others are defined. The length is the length of the data. + * All the data must be present. If that is not possible, use the + * png_write_chunk_start(), png_write_chunk_data(), and png_write_chunk_end() + * functions instead. + */ +void PNGAPI +png_write_chunk(png_structp png_ptr, png_bytep chunk_name, + png_bytep data, png_size_t length) +{ + if (png_ptr == NULL) + return; + png_write_chunk_start(png_ptr, chunk_name, (png_uint_32)length); + png_write_chunk_data(png_ptr, data, (png_size_t)length); + png_write_chunk_end(png_ptr); +} + +/* Write the start of a PNG chunk. The type is the chunk type. + * The total_length is the sum of the lengths of all the data you will be + * passing in png_write_chunk_data(). + */ +void PNGAPI +png_write_chunk_start(png_structp png_ptr, png_bytep chunk_name, + png_uint_32 length) +{ + png_byte buf[8]; + + png_debug2(0, "Writing %s chunk, length = %lu", chunk_name, + (unsigned long)length); + + if (png_ptr == NULL) + return; + +#ifdef PNG_IO_STATE_SUPPORTED + /* Inform the I/O callback that the chunk header is being written. + * PNG_IO_CHUNK_HDR requires a single I/O call. + */ + png_ptr->io_state = PNG_IO_WRITING | PNG_IO_CHUNK_HDR; +#endif + + /* Write the length and the chunk name */ + png_save_uint_32(buf, length); + png_memcpy(buf + 4, chunk_name, 4); + png_write_data(png_ptr, buf, (png_size_t)8); + /* Put the chunk name into png_ptr->chunk_name */ + png_memcpy(png_ptr->chunk_name, chunk_name, 4); + /* Reset the crc and run it over the chunk name */ + png_reset_crc(png_ptr); + png_calculate_crc(png_ptr, chunk_name, 4); + +#ifdef PNG_IO_STATE_SUPPORTED + /* Inform the I/O callback that chunk data will (possibly) be written. + * PNG_IO_CHUNK_DATA does NOT require a specific number of I/O calls. + */ + png_ptr->io_state = PNG_IO_WRITING | PNG_IO_CHUNK_DATA; +#endif +} + +/* Write the data of a PNG chunk started with png_write_chunk_start(). + * Note that multiple calls to this function are allowed, and that the + * sum of the lengths from these calls *must* add up to the total_length + * given to png_write_chunk_start(). + */ +void PNGAPI +png_write_chunk_data(png_structp png_ptr, png_bytep data, png_size_t length) +{ + /* Write the data, and run the CRC over it */ + if (png_ptr == NULL) + return; + if (data != NULL && length > 0) + { + png_write_data(png_ptr, data, length); + /* Update the CRC after writing the data, + * in case that the user I/O routine alters it. + */ + png_calculate_crc(png_ptr, data, length); + } +} + +/* Finish a chunk started with png_write_chunk_start(). */ +void PNGAPI +png_write_chunk_end(png_structp png_ptr) +{ + png_byte buf[4]; + + if (png_ptr == NULL) return; + +#ifdef PNG_IO_STATE_SUPPORTED + /* Inform the I/O callback that the chunk CRC is being written. + * PNG_IO_CHUNK_CRC requires a single I/O function call. + */ + png_ptr->io_state = PNG_IO_WRITING | PNG_IO_CHUNK_CRC; +#endif + + /* Write the crc in a single operation */ + png_save_uint_32(buf, png_ptr->crc); + + png_write_data(png_ptr, buf, (png_size_t)4); +} + +#if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_iCCP_SUPPORTED) +/* This pair of functions encapsulates the operation of (a) compressing a + * text string, and (b) issuing it later as a series of chunk data writes. + * The compression_state structure is shared context for these functions + * set up by the caller in order to make the whole mess thread-safe. + */ + +typedef struct +{ + char *input; /* The uncompressed input data */ + int input_len; /* Its length */ + int num_output_ptr; /* Number of output pointers used */ + int max_output_ptr; /* Size of output_ptr */ + png_charpp output_ptr; /* Array of pointers to output */ +} compression_state; + +/* Compress given text into storage in the png_ptr structure */ +static int /* PRIVATE */ +png_text_compress(png_structp png_ptr, + png_charp text, png_size_t text_len, int compression, + compression_state *comp) +{ + int ret; + + comp->num_output_ptr = 0; + comp->max_output_ptr = 0; + comp->output_ptr = NULL; + comp->input = NULL; + comp->input_len = 0; + + /* We may just want to pass the text right through */ + if (compression == PNG_TEXT_COMPRESSION_NONE) + { + comp->input = text; + comp->input_len = text_len; + return((int)text_len); + } + + if (compression >= PNG_TEXT_COMPRESSION_LAST) + { +#ifdef PNG_STDIO_SUPPORTED + char msg[50]; + png_snprintf(msg, 50, "Unknown compression type %d", compression); + png_warning(png_ptr, msg); +#else + png_warning(png_ptr, "Unknown compression type"); +#endif + } + + /* We can't write the chunk until we find out how much data we have, + * which means we need to run the compressor first and save the + * output. This shouldn't be a problem, as the vast majority of + * comments should be reasonable, but we will set up an array of + * malloc'd pointers to be sure. + * + * If we knew the application was well behaved, we could simplify this + * greatly by assuming we can always malloc an output buffer large + * enough to hold the compressed text ((1001 * text_len / 1000) + 12) + * and malloc this directly. The only time this would be a bad idea is + * if we can't malloc more than 64K and we have 64K of random input + * data, or if the input string is incredibly large (although this + * wouldn't cause a failure, just a slowdown due to swapping). + */ + + /* Set up the compression buffers */ + png_ptr->zstream.avail_in = (uInt)text_len; + png_ptr->zstream.next_in = (Bytef *)text; + png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size; + png_ptr->zstream.next_out = (Bytef *)png_ptr->zbuf; + + /* This is the same compression loop as in png_write_row() */ + do + { + /* Compress the data */ + ret = deflate(&png_ptr->zstream, Z_NO_FLUSH); + if (ret != Z_OK) + { + /* Error */ + if (png_ptr->zstream.msg != NULL) + png_error(png_ptr, png_ptr->zstream.msg); + else + png_error(png_ptr, "zlib error"); + } + /* Check to see if we need more room */ + if (!(png_ptr->zstream.avail_out)) + { + /* Make sure the output array has room */ + if (comp->num_output_ptr >= comp->max_output_ptr) + { + int old_max; + + old_max = comp->max_output_ptr; + comp->max_output_ptr = comp->num_output_ptr + 4; + if (comp->output_ptr != NULL) + { + png_charpp old_ptr; + + old_ptr = comp->output_ptr; + comp->output_ptr = (png_charpp)png_malloc(png_ptr, + (png_alloc_size_t) + (comp->max_output_ptr * png_sizeof(png_charpp))); + png_memcpy(comp->output_ptr, old_ptr, old_max + * png_sizeof(png_charp)); + png_free(png_ptr, old_ptr); + } + else + comp->output_ptr = (png_charpp)png_malloc(png_ptr, + (png_alloc_size_t) + (comp->max_output_ptr * png_sizeof(png_charp))); + } + + /* Save the data */ + comp->output_ptr[comp->num_output_ptr] = + (png_charp)png_malloc(png_ptr, + (png_alloc_size_t)png_ptr->zbuf_size); + png_memcpy(comp->output_ptr[comp->num_output_ptr], png_ptr->zbuf, + png_ptr->zbuf_size); + comp->num_output_ptr++; + + /* and reset the buffer */ + png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size; + png_ptr->zstream.next_out = png_ptr->zbuf; + } + /* Continue until we don't have any more to compress */ + } while (png_ptr->zstream.avail_in); + + /* Finish the compression */ + do + { + /* Tell zlib we are finished */ + ret = deflate(&png_ptr->zstream, Z_FINISH); + + if (ret == Z_OK) + { + /* Check to see if we need more room */ + if (!(png_ptr->zstream.avail_out)) + { + /* Check to make sure our output array has room */ + if (comp->num_output_ptr >= comp->max_output_ptr) + { + int old_max; + + old_max = comp->max_output_ptr; + comp->max_output_ptr = comp->num_output_ptr + 4; + if (comp->output_ptr != NULL) + { + png_charpp old_ptr; + + old_ptr = comp->output_ptr; + /* This could be optimized to realloc() */ + comp->output_ptr = (png_charpp)png_malloc(png_ptr, + (png_alloc_size_t)(comp->max_output_ptr * + png_sizeof(png_charp))); + png_memcpy(comp->output_ptr, old_ptr, + old_max * png_sizeof(png_charp)); + png_free(png_ptr, old_ptr); + } + else + comp->output_ptr = (png_charpp)png_malloc(png_ptr, + (png_alloc_size_t)(comp->max_output_ptr * + png_sizeof(png_charp))); + } + + /* Save the data */ + comp->output_ptr[comp->num_output_ptr] = + (png_charp)png_malloc(png_ptr, + (png_alloc_size_t)png_ptr->zbuf_size); + png_memcpy(comp->output_ptr[comp->num_output_ptr], png_ptr->zbuf, + png_ptr->zbuf_size); + comp->num_output_ptr++; + + /* and reset the buffer pointers */ + png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size; + png_ptr->zstream.next_out = png_ptr->zbuf; + } + } + else if (ret != Z_STREAM_END) + { + /* We got an error */ + if (png_ptr->zstream.msg != NULL) + png_error(png_ptr, png_ptr->zstream.msg); + else + png_error(png_ptr, "zlib error"); + } + } while (ret != Z_STREAM_END); + + /* Text length is number of buffers plus last buffer */ + text_len = png_ptr->zbuf_size * comp->num_output_ptr; + if (png_ptr->zstream.avail_out < png_ptr->zbuf_size) + text_len += png_ptr->zbuf_size - (png_size_t)png_ptr->zstream.avail_out; + + return((int)text_len); +} + +/* Ship the compressed text out via chunk writes */ +static void /* PRIVATE */ +png_write_compressed_data_out(png_structp png_ptr, compression_state *comp) +{ + int i; + + /* Handle the no-compression case */ + if (comp->input) + { + png_write_chunk_data(png_ptr, (png_bytep)comp->input, + (png_size_t)comp->input_len); + return; + } + + /* Write saved output buffers, if any */ + for (i = 0; i < comp->num_output_ptr; i++) + { + png_write_chunk_data(png_ptr, (png_bytep)comp->output_ptr[i], + (png_size_t)png_ptr->zbuf_size); + png_free(png_ptr, comp->output_ptr[i]); + } + if (comp->max_output_ptr != 0) + png_free(png_ptr, comp->output_ptr); + /* Write anything left in zbuf */ + if (png_ptr->zstream.avail_out < (png_uint_32)png_ptr->zbuf_size) + png_write_chunk_data(png_ptr, png_ptr->zbuf, + (png_size_t)(png_ptr->zbuf_size - png_ptr->zstream.avail_out)); + + /* Reset zlib for another zTXt/iTXt or image data */ + deflateReset(&png_ptr->zstream); + png_ptr->zstream.data_type = Z_BINARY; +} +#endif + +/* Write the IHDR chunk, and update the png_struct with the necessary + * information. Note that the rest of this code depends upon this + * information being correct. + */ +void /* PRIVATE */ +png_write_IHDR(png_structp png_ptr, png_uint_32 width, png_uint_32 height, + int bit_depth, int color_type, int compression_type, int filter_type, + int interlace_type) +{ + PNG_IHDR; + int ret; + + png_byte buf[13]; /* Buffer to store the IHDR info */ + + png_debug(1, "in png_write_IHDR"); + + /* Check that we have valid input data from the application info */ + switch (color_type) + { + case PNG_COLOR_TYPE_GRAY: + switch (bit_depth) + { + case 1: + case 2: + case 4: + case 8: + case 16: png_ptr->channels = 1; break; + default: png_error(png_ptr, + "Invalid bit depth for grayscale image"); + } + break; + case PNG_COLOR_TYPE_RGB: + if (bit_depth != 8 && bit_depth != 16) + png_error(png_ptr, "Invalid bit depth for RGB image"); + png_ptr->channels = 3; + break; + case PNG_COLOR_TYPE_PALETTE: + switch (bit_depth) + { + case 1: + case 2: + case 4: + case 8: png_ptr->channels = 1; break; + default: png_error(png_ptr, "Invalid bit depth for paletted image"); + } + break; + case PNG_COLOR_TYPE_GRAY_ALPHA: + if (bit_depth != 8 && bit_depth != 16) + png_error(png_ptr, "Invalid bit depth for grayscale+alpha image"); + png_ptr->channels = 2; + break; + case PNG_COLOR_TYPE_RGB_ALPHA: + if (bit_depth != 8 && bit_depth != 16) + png_error(png_ptr, "Invalid bit depth for RGBA image"); + png_ptr->channels = 4; + break; + default: + png_error(png_ptr, "Invalid image color type specified"); + } + + if (compression_type != PNG_COMPRESSION_TYPE_BASE) + { + png_warning(png_ptr, "Invalid compression type specified"); + compression_type = PNG_COMPRESSION_TYPE_BASE; + } + + /* Write filter_method 64 (intrapixel differencing) only if + * 1. Libpng was compiled with PNG_MNG_FEATURES_SUPPORTED and + * 2. Libpng did not write a PNG signature (this filter_method is only + * used in PNG datastreams that are embedded in MNG datastreams) and + * 3. The application called png_permit_mng_features with a mask that + * included PNG_FLAG_MNG_FILTER_64 and + * 4. The filter_method is 64 and + * 5. The color_type is RGB or RGBA + */ + if ( +#ifdef PNG_MNG_FEATURES_SUPPORTED + !((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) && + ((png_ptr->mode&PNG_HAVE_PNG_SIGNATURE) == 0) && + (color_type == PNG_COLOR_TYPE_RGB || + color_type == PNG_COLOR_TYPE_RGB_ALPHA) && + (filter_type == PNG_INTRAPIXEL_DIFFERENCING)) && +#endif + filter_type != PNG_FILTER_TYPE_BASE) + { + png_warning(png_ptr, "Invalid filter type specified"); + filter_type = PNG_FILTER_TYPE_BASE; + } + +#ifdef PNG_WRITE_INTERLACING_SUPPORTED + if (interlace_type != PNG_INTERLACE_NONE && + interlace_type != PNG_INTERLACE_ADAM7) + { + png_warning(png_ptr, "Invalid interlace type specified"); + interlace_type = PNG_INTERLACE_ADAM7; + } +#else + interlace_type=PNG_INTERLACE_NONE; +#endif + + /* Save the relevent information */ + png_ptr->bit_depth = (png_byte)bit_depth; + png_ptr->color_type = (png_byte)color_type; + png_ptr->interlaced = (png_byte)interlace_type; +#ifdef PNG_MNG_FEATURES_SUPPORTED + png_ptr->filter_type = (png_byte)filter_type; +#endif + png_ptr->compression_type = (png_byte)compression_type; + png_ptr->width = width; + png_ptr->height = height; + + png_ptr->pixel_depth = (png_byte)(bit_depth * png_ptr->channels); + png_ptr->rowbytes = PNG_ROWBYTES(png_ptr->pixel_depth, width); + /* Set the usr info, so any transformations can modify it */ + png_ptr->usr_width = png_ptr->width; + png_ptr->usr_bit_depth = png_ptr->bit_depth; + png_ptr->usr_channels = png_ptr->channels; + + /* Pack the header information into the buffer */ + png_save_uint_32(buf, width); + png_save_uint_32(buf + 4, height); + buf[8] = (png_byte)bit_depth; + buf[9] = (png_byte)color_type; + buf[10] = (png_byte)compression_type; + buf[11] = (png_byte)filter_type; + buf[12] = (png_byte)interlace_type; + + /* Write the chunk */ + png_write_chunk(png_ptr, (png_bytep)png_IHDR, buf, (png_size_t)13); + + /* Initialize zlib with PNG info */ + png_ptr->zstream.zalloc = png_zalloc; + png_ptr->zstream.zfree = png_zfree; + png_ptr->zstream.opaque = (voidpf)png_ptr; + if (!(png_ptr->do_filter)) + { + if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE || + png_ptr->bit_depth < 8) + png_ptr->do_filter = PNG_FILTER_NONE; + else + png_ptr->do_filter = PNG_ALL_FILTERS; + } + if (!(png_ptr->flags & PNG_FLAG_ZLIB_CUSTOM_STRATEGY)) + { + if (png_ptr->do_filter != PNG_FILTER_NONE) + png_ptr->zlib_strategy = Z_FILTERED; + else + png_ptr->zlib_strategy = Z_DEFAULT_STRATEGY; + } + if (!(png_ptr->flags & PNG_FLAG_ZLIB_CUSTOM_LEVEL)) + png_ptr->zlib_level = Z_DEFAULT_COMPRESSION; + if (!(png_ptr->flags & PNG_FLAG_ZLIB_CUSTOM_MEM_LEVEL)) + png_ptr->zlib_mem_level = 8; + if (!(png_ptr->flags & PNG_FLAG_ZLIB_CUSTOM_WINDOW_BITS)) + png_ptr->zlib_window_bits = 15; + if (!(png_ptr->flags & PNG_FLAG_ZLIB_CUSTOM_METHOD)) + png_ptr->zlib_method = 8; + ret = deflateInit2(&png_ptr->zstream, png_ptr->zlib_level, + png_ptr->zlib_method, png_ptr->zlib_window_bits, + png_ptr->zlib_mem_level, png_ptr->zlib_strategy); + if (ret != Z_OK) + { + if (ret == Z_VERSION_ERROR) png_error(png_ptr, + "zlib failed to initialize compressor -- version error"); + if (ret == Z_STREAM_ERROR) png_error(png_ptr, + "zlib failed to initialize compressor -- stream error"); + if (ret == Z_MEM_ERROR) png_error(png_ptr, + "zlib failed to initialize compressor -- mem error"); + png_error(png_ptr, "zlib failed to initialize compressor"); + } + png_ptr->zstream.next_out = png_ptr->zbuf; + png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size; + /* libpng is not interested in zstream.data_type */ + /* Set it to a predefined value, to avoid its evaluation inside zlib */ + png_ptr->zstream.data_type = Z_BINARY; + + png_ptr->mode = PNG_HAVE_IHDR; +} + +/* Write the palette. We are careful not to trust png_color to be in the + * correct order for PNG, so people can redefine it to any convenient + * structure. + */ +void /* PRIVATE */ +png_write_PLTE(png_structp png_ptr, png_colorp palette, png_uint_32 num_pal) +{ + PNG_PLTE; + png_uint_32 i; + png_colorp pal_ptr; + png_byte buf[3]; + + png_debug(1, "in png_write_PLTE"); + + if (( +#ifdef PNG_MNG_FEATURES_SUPPORTED + !(png_ptr->mng_features_permitted & PNG_FLAG_MNG_EMPTY_PLTE) && +#endif + num_pal == 0) || num_pal > 256) + { + if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) + { + png_error(png_ptr, "Invalid number of colors in palette"); + } + else + { + png_warning(png_ptr, "Invalid number of colors in palette"); + return; + } + } + + if (!(png_ptr->color_type&PNG_COLOR_MASK_COLOR)) + { + png_warning(png_ptr, + "Ignoring request to write a PLTE chunk in grayscale PNG"); + return; + } + + png_ptr->num_palette = (png_uint_16)num_pal; + png_debug1(3, "num_palette = %d", png_ptr->num_palette); + + png_write_chunk_start(png_ptr, (png_bytep)png_PLTE, + (png_uint_32)(num_pal * 3)); +#ifdef PNG_POINTER_INDEXING_SUPPORTED + for (i = 0, pal_ptr = palette; i < num_pal; i++, pal_ptr++) + { + buf[0] = pal_ptr->red; + buf[1] = pal_ptr->green; + buf[2] = pal_ptr->blue; + png_write_chunk_data(png_ptr, buf, (png_size_t)3); + } +#else + /* This is a little slower but some buggy compilers need to do this + * instead + */ + pal_ptr=palette; + for (i = 0; i < num_pal; i++) + { + buf[0] = pal_ptr[i].red; + buf[1] = pal_ptr[i].green; + buf[2] = pal_ptr[i].blue; + png_write_chunk_data(png_ptr, buf, (png_size_t)3); + } +#endif + png_write_chunk_end(png_ptr); + png_ptr->mode |= PNG_HAVE_PLTE; +} + +/* Write an IDAT chunk */ +void /* PRIVATE */ +png_write_IDAT(png_structp png_ptr, png_bytep data, png_size_t length) +{ + PNG_IDAT; + + png_debug(1, "in png_write_IDAT"); + + /* Optimize the CMF field in the zlib stream. */ + /* This hack of the zlib stream is compliant to the stream specification. */ + if (!(png_ptr->mode & PNG_HAVE_IDAT) && + png_ptr->compression_type == PNG_COMPRESSION_TYPE_BASE) + { + unsigned int z_cmf = data[0]; /* zlib compression method and flags */ + if ((z_cmf & 0x0f) == 8 && (z_cmf & 0xf0) <= 0x70) + { + /* Avoid memory underflows and multiplication overflows. + * + * The conditions below are practically always satisfied; + * however, they still must be checked. + */ + if (length >= 2 && + png_ptr->height < 16384 && png_ptr->width < 16384) + { + png_uint_32 uncompressed_idat_size = png_ptr->height * + ((png_ptr->width * + png_ptr->channels * png_ptr->bit_depth + 15) >> 3); + unsigned int z_cinfo = z_cmf >> 4; + unsigned int half_z_window_size = 1 << (z_cinfo + 7); + while (uncompressed_idat_size <= half_z_window_size && + half_z_window_size >= 256) + { + z_cinfo--; + half_z_window_size >>= 1; + } + z_cmf = (z_cmf & 0x0f) | (z_cinfo << 4); + if (data[0] != (png_byte)z_cmf) + { + data[0] = (png_byte)z_cmf; + data[1] &= 0xe0; + data[1] += (png_byte)(0x1f - ((z_cmf << 8) + data[1]) % 0x1f); + } + } + } + else + png_error(png_ptr, + "Invalid zlib compression method or flags in IDAT"); + } + + png_write_chunk(png_ptr, (png_bytep)png_IDAT, data, length); + png_ptr->mode |= PNG_HAVE_IDAT; +} + +/* Write an IEND chunk */ +void /* PRIVATE */ +png_write_IEND(png_structp png_ptr) +{ + PNG_IEND; + + png_debug(1, "in png_write_IEND"); + + png_write_chunk(png_ptr, (png_bytep)png_IEND, NULL, + (png_size_t)0); + png_ptr->mode |= PNG_HAVE_IEND; +} + +#ifdef PNG_WRITE_gAMA_SUPPORTED +/* Write a gAMA chunk */ +#ifdef PNG_FLOATING_POINT_SUPPORTED +void /* PRIVATE */ +png_write_gAMA(png_structp png_ptr, double file_gamma) +{ + PNG_gAMA; + png_uint_32 igamma; + png_byte buf[4]; + + png_debug(1, "in png_write_gAMA"); + + /* file_gamma is saved in 1/100,000ths */ + igamma = (png_uint_32)(file_gamma * 100000.0 + 0.5); + png_save_uint_32(buf, igamma); + png_write_chunk(png_ptr, (png_bytep)png_gAMA, buf, (png_size_t)4); +} +#endif +#ifdef PNG_FIXED_POINT_SUPPORTED +void /* PRIVATE */ +png_write_gAMA_fixed(png_structp png_ptr, png_fixed_point file_gamma) +{ + PNG_gAMA; + png_byte buf[4]; + + png_debug(1, "in png_write_gAMA"); + + /* file_gamma is saved in 1/100,000ths */ + png_save_uint_32(buf, (png_uint_32)file_gamma); + png_write_chunk(png_ptr, (png_bytep)png_gAMA, buf, (png_size_t)4); +} +#endif +#endif + +#ifdef PNG_WRITE_sRGB_SUPPORTED +/* Write a sRGB chunk */ +void /* PRIVATE */ +png_write_sRGB(png_structp png_ptr, int srgb_intent) +{ + PNG_sRGB; + png_byte buf[1]; + + png_debug(1, "in png_write_sRGB"); + + if (srgb_intent >= PNG_sRGB_INTENT_LAST) + png_warning(png_ptr, + "Invalid sRGB rendering intent specified"); + buf[0]=(png_byte)srgb_intent; + png_write_chunk(png_ptr, (png_bytep)png_sRGB, buf, (png_size_t)1); +} +#endif + +#ifdef PNG_WRITE_iCCP_SUPPORTED +/* Write an iCCP chunk */ +void /* PRIVATE */ +png_write_iCCP(png_structp png_ptr, png_charp name, int compression_type, + png_charp profile, int profile_len) +{ + PNG_iCCP; + png_size_t name_len; + png_charp new_name; + compression_state comp; + int embedded_profile_len = 0; + + png_debug(1, "in png_write_iCCP"); + + comp.num_output_ptr = 0; + comp.max_output_ptr = 0; + comp.output_ptr = NULL; + comp.input = NULL; + comp.input_len = 0; + + if ((name_len = png_check_keyword(png_ptr, name, + &new_name)) == 0) + return; + + if (compression_type != PNG_COMPRESSION_TYPE_BASE) + png_warning(png_ptr, "Unknown compression type in iCCP chunk"); + + if (profile == NULL) + profile_len = 0; + + if (profile_len > 3) + embedded_profile_len = + ((*( (png_bytep)profile ))<<24) | + ((*( (png_bytep)profile + 1))<<16) | + ((*( (png_bytep)profile + 2))<< 8) | + ((*( (png_bytep)profile + 3)) ); + + if (embedded_profile_len < 0) + { + png_warning(png_ptr, + "Embedded profile length in iCCP chunk is negative"); + png_free(png_ptr, new_name); + return; + } + + if (profile_len < embedded_profile_len) + { + png_warning(png_ptr, + "Embedded profile length too large in iCCP chunk"); + png_free(png_ptr, new_name); + return; + } + + if (profile_len > embedded_profile_len) + { + png_warning(png_ptr, + "Truncating profile to actual length in iCCP chunk"); + profile_len = embedded_profile_len; + } + + if (profile_len) + profile_len = png_text_compress(png_ptr, profile, + (png_size_t)profile_len, PNG_COMPRESSION_TYPE_BASE, &comp); + + /* Make sure we include the NULL after the name and the compression type */ + png_write_chunk_start(png_ptr, (png_bytep)png_iCCP, + (png_uint_32)(name_len + profile_len + 2)); + new_name[name_len + 1] = 0x00; + png_write_chunk_data(png_ptr, (png_bytep)new_name, + (png_size_t)(name_len + 2)); + + if (profile_len) + png_write_compressed_data_out(png_ptr, &comp); + + png_write_chunk_end(png_ptr); + png_free(png_ptr, new_name); +} +#endif + +#ifdef PNG_WRITE_sPLT_SUPPORTED +/* Write a sPLT chunk */ +void /* PRIVATE */ +png_write_sPLT(png_structp png_ptr, png_sPLT_tp spalette) +{ + PNG_sPLT; + png_size_t name_len; + png_charp new_name; + png_byte entrybuf[10]; + png_size_t entry_size = (spalette->depth == 8 ? 6 : 10); + png_size_t palette_size = entry_size * spalette->nentries; + png_sPLT_entryp ep; +#ifndef PNG_POINTER_INDEXING_SUPPORTED + int i; +#endif + + png_debug(1, "in png_write_sPLT"); + + if ((name_len = png_check_keyword(png_ptr,spalette->name, &new_name))==0) + return; + + /* Make sure we include the NULL after the name */ + png_write_chunk_start(png_ptr, (png_bytep)png_sPLT, + (png_uint_32)(name_len + 2 + palette_size)); + png_write_chunk_data(png_ptr, (png_bytep)new_name, + (png_size_t)(name_len + 1)); + png_write_chunk_data(png_ptr, (png_bytep)&spalette->depth, (png_size_t)1); + + /* Loop through each palette entry, writing appropriately */ +#ifdef PNG_POINTER_INDEXING_SUPPORTED + for (ep = spalette->entries; epentries + spalette->nentries; ep++) + { + if (spalette->depth == 8) + { + entrybuf[0] = (png_byte)ep->red; + entrybuf[1] = (png_byte)ep->green; + entrybuf[2] = (png_byte)ep->blue; + entrybuf[3] = (png_byte)ep->alpha; + png_save_uint_16(entrybuf + 4, ep->frequency); + } + else + { + png_save_uint_16(entrybuf + 0, ep->red); + png_save_uint_16(entrybuf + 2, ep->green); + png_save_uint_16(entrybuf + 4, ep->blue); + png_save_uint_16(entrybuf + 6, ep->alpha); + png_save_uint_16(entrybuf + 8, ep->frequency); + } + png_write_chunk_data(png_ptr, entrybuf, (png_size_t)entry_size); + } +#else + ep=spalette->entries; + for (i=0; i>spalette->nentries; i++) + { + if (spalette->depth == 8) + { + entrybuf[0] = (png_byte)ep[i].red; + entrybuf[1] = (png_byte)ep[i].green; + entrybuf[2] = (png_byte)ep[i].blue; + entrybuf[3] = (png_byte)ep[i].alpha; + png_save_uint_16(entrybuf + 4, ep[i].frequency); + } + else + { + png_save_uint_16(entrybuf + 0, ep[i].red); + png_save_uint_16(entrybuf + 2, ep[i].green); + png_save_uint_16(entrybuf + 4, ep[i].blue); + png_save_uint_16(entrybuf + 6, ep[i].alpha); + png_save_uint_16(entrybuf + 8, ep[i].frequency); + } + png_write_chunk_data(png_ptr, entrybuf, (png_size_t)entry_size); + } +#endif + + png_write_chunk_end(png_ptr); + png_free(png_ptr, new_name); +} +#endif + +#ifdef PNG_WRITE_sBIT_SUPPORTED +/* Write the sBIT chunk */ +void /* PRIVATE */ +png_write_sBIT(png_structp png_ptr, png_color_8p sbit, int color_type) +{ + PNG_sBIT; + png_byte buf[4]; + png_size_t size; + + png_debug(1, "in png_write_sBIT"); + + /* Make sure we don't depend upon the order of PNG_COLOR_8 */ + if (color_type & PNG_COLOR_MASK_COLOR) + { + png_byte maxbits; + + maxbits = (png_byte)(color_type==PNG_COLOR_TYPE_PALETTE ? 8 : + png_ptr->usr_bit_depth); + if (sbit->red == 0 || sbit->red > maxbits || + sbit->green == 0 || sbit->green > maxbits || + sbit->blue == 0 || sbit->blue > maxbits) + { + png_warning(png_ptr, "Invalid sBIT depth specified"); + return; + } + buf[0] = sbit->red; + buf[1] = sbit->green; + buf[2] = sbit->blue; + size = 3; + } + else + { + if (sbit->gray == 0 || sbit->gray > png_ptr->usr_bit_depth) + { + png_warning(png_ptr, "Invalid sBIT depth specified"); + return; + } + buf[0] = sbit->gray; + size = 1; + } + + if (color_type & PNG_COLOR_MASK_ALPHA) + { + if (sbit->alpha == 0 || sbit->alpha > png_ptr->usr_bit_depth) + { + png_warning(png_ptr, "Invalid sBIT depth specified"); + return; + } + buf[size++] = sbit->alpha; + } + + png_write_chunk(png_ptr, (png_bytep)png_sBIT, buf, size); +} +#endif + +#ifdef PNG_WRITE_cHRM_SUPPORTED +/* Write the cHRM chunk */ +#ifdef PNG_FLOATING_POINT_SUPPORTED +void /* PRIVATE */ +png_write_cHRM(png_structp png_ptr, double white_x, double white_y, + double red_x, double red_y, double green_x, double green_y, + double blue_x, double blue_y) +{ + PNG_cHRM; + png_byte buf[32]; + + png_fixed_point int_white_x, int_white_y, int_red_x, int_red_y, + int_green_x, int_green_y, int_blue_x, int_blue_y; + + png_debug(1, "in png_write_cHRM"); + + int_white_x = (png_uint_32)(white_x * 100000.0 + 0.5); + int_white_y = (png_uint_32)(white_y * 100000.0 + 0.5); + int_red_x = (png_uint_32)(red_x * 100000.0 + 0.5); + int_red_y = (png_uint_32)(red_y * 100000.0 + 0.5); + int_green_x = (png_uint_32)(green_x * 100000.0 + 0.5); + int_green_y = (png_uint_32)(green_y * 100000.0 + 0.5); + int_blue_x = (png_uint_32)(blue_x * 100000.0 + 0.5); + int_blue_y = (png_uint_32)(blue_y * 100000.0 + 0.5); + +#ifdef PNG_CHECK_cHRM_SUPPORTED + if (png_check_cHRM_fixed(png_ptr, int_white_x, int_white_y, + int_red_x, int_red_y, int_green_x, int_green_y, int_blue_x, int_blue_y)) +#endif + { + /* Each value is saved in 1/100,000ths */ + + png_save_uint_32(buf, int_white_x); + png_save_uint_32(buf + 4, int_white_y); + + png_save_uint_32(buf + 8, int_red_x); + png_save_uint_32(buf + 12, int_red_y); + + png_save_uint_32(buf + 16, int_green_x); + png_save_uint_32(buf + 20, int_green_y); + + png_save_uint_32(buf + 24, int_blue_x); + png_save_uint_32(buf + 28, int_blue_y); + + png_write_chunk(png_ptr, (png_bytep)png_cHRM, buf, (png_size_t)32); + } +} +#endif +#ifdef PNG_FIXED_POINT_SUPPORTED +void /* PRIVATE */ +png_write_cHRM_fixed(png_structp png_ptr, png_fixed_point white_x, + png_fixed_point white_y, png_fixed_point red_x, png_fixed_point red_y, + png_fixed_point green_x, png_fixed_point green_y, png_fixed_point blue_x, + png_fixed_point blue_y) +{ + PNG_cHRM; + png_byte buf[32]; + + png_debug(1, "in png_write_cHRM"); + + /* Each value is saved in 1/100,000ths */ +#ifdef PNG_CHECK_cHRM_SUPPORTED + if (png_check_cHRM_fixed(png_ptr, white_x, white_y, red_x, red_y, + green_x, green_y, blue_x, blue_y)) +#endif + { + png_save_uint_32(buf, (png_uint_32)white_x); + png_save_uint_32(buf + 4, (png_uint_32)white_y); + + png_save_uint_32(buf + 8, (png_uint_32)red_x); + png_save_uint_32(buf + 12, (png_uint_32)red_y); + + png_save_uint_32(buf + 16, (png_uint_32)green_x); + png_save_uint_32(buf + 20, (png_uint_32)green_y); + + png_save_uint_32(buf + 24, (png_uint_32)blue_x); + png_save_uint_32(buf + 28, (png_uint_32)blue_y); + + png_write_chunk(png_ptr, (png_bytep)png_cHRM, buf, (png_size_t)32); + } +} +#endif +#endif + +#ifdef PNG_WRITE_tRNS_SUPPORTED +/* Write the tRNS chunk */ +void /* PRIVATE */ +png_write_tRNS(png_structp png_ptr, png_bytep trans_alpha, png_color_16p tran, + int num_trans, int color_type) +{ + PNG_tRNS; + png_byte buf[6]; + + png_debug(1, "in png_write_tRNS"); + + if (color_type == PNG_COLOR_TYPE_PALETTE) + { + if (num_trans <= 0 || num_trans > (int)png_ptr->num_palette) + { + png_warning(png_ptr, "Invalid number of transparent colors specified"); + return; + } + /* Write the chunk out as it is */ + png_write_chunk(png_ptr, (png_bytep)png_tRNS, trans_alpha, + (png_size_t)num_trans); + } + else if (color_type == PNG_COLOR_TYPE_GRAY) + { + /* One 16 bit value */ + if (tran->gray >= (1 << png_ptr->bit_depth)) + { + png_warning(png_ptr, + "Ignoring attempt to write tRNS chunk out-of-range for bit_depth"); + return; + } + png_save_uint_16(buf, tran->gray); + png_write_chunk(png_ptr, (png_bytep)png_tRNS, buf, (png_size_t)2); + } + else if (color_type == PNG_COLOR_TYPE_RGB) + { + /* Three 16 bit values */ + png_save_uint_16(buf, tran->red); + png_save_uint_16(buf + 2, tran->green); + png_save_uint_16(buf + 4, tran->blue); + if (png_ptr->bit_depth == 8 && (buf[0] | buf[2] | buf[4])) + { + png_warning(png_ptr, + "Ignoring attempt to write 16-bit tRNS chunk when bit_depth is 8"); + return; + } + png_write_chunk(png_ptr, (png_bytep)png_tRNS, buf, (png_size_t)6); + } + else + { + png_warning(png_ptr, "Can't write tRNS with an alpha channel"); + } +} +#endif + +#ifdef PNG_WRITE_bKGD_SUPPORTED +/* Write the background chunk */ +void /* PRIVATE */ +png_write_bKGD(png_structp png_ptr, png_color_16p back, int color_type) +{ + PNG_bKGD; + png_byte buf[6]; + + png_debug(1, "in png_write_bKGD"); + + if (color_type == PNG_COLOR_TYPE_PALETTE) + { + if ( +#ifdef PNG_MNG_FEATURES_SUPPORTED + (png_ptr->num_palette || + (!(png_ptr->mng_features_permitted & PNG_FLAG_MNG_EMPTY_PLTE))) && +#endif + back->index >= png_ptr->num_palette) + { + png_warning(png_ptr, "Invalid background palette index"); + return; + } + buf[0] = back->index; + png_write_chunk(png_ptr, (png_bytep)png_bKGD, buf, (png_size_t)1); + } + else if (color_type & PNG_COLOR_MASK_COLOR) + { + png_save_uint_16(buf, back->red); + png_save_uint_16(buf + 2, back->green); + png_save_uint_16(buf + 4, back->blue); + if (png_ptr->bit_depth == 8 && (buf[0] | buf[2] | buf[4])) + { + png_warning(png_ptr, + "Ignoring attempt to write 16-bit bKGD chunk when bit_depth is 8"); + return; + } + png_write_chunk(png_ptr, (png_bytep)png_bKGD, buf, (png_size_t)6); + } + else + { + if (back->gray >= (1 << png_ptr->bit_depth)) + { + png_warning(png_ptr, + "Ignoring attempt to write bKGD chunk out-of-range for bit_depth"); + return; + } + png_save_uint_16(buf, back->gray); + png_write_chunk(png_ptr, (png_bytep)png_bKGD, buf, (png_size_t)2); + } +} +#endif + +#ifdef PNG_WRITE_hIST_SUPPORTED +/* Write the histogram */ +void /* PRIVATE */ +png_write_hIST(png_structp png_ptr, png_uint_16p hist, int num_hist) +{ + PNG_hIST; + int i; + png_byte buf[3]; + + png_debug(1, "in png_write_hIST"); + + if (num_hist > (int)png_ptr->num_palette) + { + png_debug2(3, "num_hist = %d, num_palette = %d", num_hist, + png_ptr->num_palette); + png_warning(png_ptr, "Invalid number of histogram entries specified"); + return; + } + + png_write_chunk_start(png_ptr, (png_bytep)png_hIST, + (png_uint_32)(num_hist * 2)); + for (i = 0; i < num_hist; i++) + { + png_save_uint_16(buf, hist[i]); + png_write_chunk_data(png_ptr, buf, (png_size_t)2); + } + png_write_chunk_end(png_ptr); +} +#endif + +#if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_pCAL_SUPPORTED) || \ + defined(PNG_WRITE_iCCP_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED) +/* Check that the tEXt or zTXt keyword is valid per PNG 1.0 specification, + * and if invalid, correct the keyword rather than discarding the entire + * chunk. The PNG 1.0 specification requires keywords 1-79 characters in + * length, forbids leading or trailing whitespace, multiple internal spaces, + * and the non-break space (0x80) from ISO 8859-1. Returns keyword length. + * + * The new_key is allocated to hold the corrected keyword and must be freed + * by the calling routine. This avoids problems with trying to write to + * static keywords without having to have duplicate copies of the strings. + */ +png_size_t /* PRIVATE */ +png_check_keyword(png_structp png_ptr, png_charp key, png_charpp new_key) +{ + png_size_t key_len; + png_charp kp, dp; + int kflag; + int kwarn=0; + + png_debug(1, "in png_check_keyword"); + + *new_key = NULL; + + if (key == NULL || (key_len = png_strlen(key)) == 0) + { + png_warning(png_ptr, "zero length keyword"); + return ((png_size_t)0); + } + + png_debug1(2, "Keyword to be checked is '%s'", key); + + *new_key = (png_charp)png_malloc_warn(png_ptr, (png_uint_32)(key_len + 2)); + if (*new_key == NULL) + { + png_warning(png_ptr, "Out of memory while procesing keyword"); + return ((png_size_t)0); + } + + /* Replace non-printing characters with a blank and print a warning */ + for (kp = key, dp = *new_key; *kp != '\0'; kp++, dp++) + { + if ((png_byte)*kp < 0x20 || + ((png_byte)*kp > 0x7E && (png_byte)*kp < 0xA1)) + { +#ifdef PNG_STDIO_SUPPORTED + char msg[40]; + + png_snprintf(msg, 40, + "invalid keyword character 0x%02X", (png_byte)*kp); + png_warning(png_ptr, msg); +#else + png_warning(png_ptr, "invalid character in keyword"); +#endif + *dp = ' '; + } + else + { + *dp = *kp; + } + } + *dp = '\0'; + + /* Remove any trailing white space. */ + kp = *new_key + key_len - 1; + if (*kp == ' ') + { + png_warning(png_ptr, "trailing spaces removed from keyword"); + + while (*kp == ' ') + { + *(kp--) = '\0'; + key_len--; + } + } + + /* Remove any leading white space. */ + kp = *new_key; + if (*kp == ' ') + { + png_warning(png_ptr, "leading spaces removed from keyword"); + + while (*kp == ' ') + { + kp++; + key_len--; + } + } + + png_debug1(2, "Checking for multiple internal spaces in '%s'", kp); + + /* Remove multiple internal spaces. */ + for (kflag = 0, dp = *new_key; *kp != '\0'; kp++) + { + if (*kp == ' ' && kflag == 0) + { + *(dp++) = *kp; + kflag = 1; + } + else if (*kp == ' ') + { + key_len--; + kwarn=1; + } + else + { + *(dp++) = *kp; + kflag = 0; + } + } + *dp = '\0'; + if (kwarn) + png_warning(png_ptr, "extra interior spaces removed from keyword"); + + if (key_len == 0) + { + png_free(png_ptr, *new_key); + png_warning(png_ptr, "Zero length keyword"); + } + + if (key_len > 79) + { + png_warning(png_ptr, "keyword length must be 1 - 79 characters"); + (*new_key)[79] = '\0'; + key_len = 79; + } + + return (key_len); +} +#endif + +#ifdef PNG_WRITE_tEXt_SUPPORTED +/* Write a tEXt chunk */ +void /* PRIVATE */ +png_write_tEXt(png_structp png_ptr, png_charp key, png_charp text, + png_size_t text_len) +{ + PNG_tEXt; + png_size_t key_len; + png_charp new_key; + + png_debug(1, "in png_write_tEXt"); + + if ((key_len = png_check_keyword(png_ptr, key, &new_key))==0) + return; + + if (text == NULL || *text == '\0') + text_len = 0; + else + text_len = png_strlen(text); + + /* Make sure we include the 0 after the key */ + png_write_chunk_start(png_ptr, (png_bytep)png_tEXt, + (png_uint_32)(key_len + text_len + 1)); + /* + * We leave it to the application to meet PNG-1.0 requirements on the + * contents of the text. PNG-1.0 through PNG-1.2 discourage the use of + * any non-Latin-1 characters except for NEWLINE. ISO PNG will forbid them. + * The NUL character is forbidden by PNG-1.0 through PNG-1.2 and ISO PNG. + */ + png_write_chunk_data(png_ptr, (png_bytep)new_key, + (png_size_t)(key_len + 1)); + if (text_len) + png_write_chunk_data(png_ptr, (png_bytep)text, (png_size_t)text_len); + + png_write_chunk_end(png_ptr); + png_free(png_ptr, new_key); +} +#endif + +#ifdef PNG_WRITE_zTXt_SUPPORTED +/* Write a compressed text chunk */ +void /* PRIVATE */ +png_write_zTXt(png_structp png_ptr, png_charp key, png_charp text, + png_size_t text_len, int compression) +{ + PNG_zTXt; + png_size_t key_len; + char buf[1]; + png_charp new_key; + compression_state comp; + + png_debug(1, "in png_write_zTXt"); + + comp.num_output_ptr = 0; + comp.max_output_ptr = 0; + comp.output_ptr = NULL; + comp.input = NULL; + comp.input_len = 0; + + if ((key_len = png_check_keyword(png_ptr, key, &new_key))==0) + { + png_free(png_ptr, new_key); + return; + } + + if (text == NULL || *text == '\0' || compression==PNG_TEXT_COMPRESSION_NONE) + { + png_write_tEXt(png_ptr, new_key, text, (png_size_t)0); + png_free(png_ptr, new_key); + return; + } + + text_len = png_strlen(text); + + /* Compute the compressed data; do it now for the length */ + text_len = png_text_compress(png_ptr, text, text_len, compression, + &comp); + + /* Write start of chunk */ + png_write_chunk_start(png_ptr, (png_bytep)png_zTXt, + (png_uint_32)(key_len+text_len + 2)); + /* Write key */ + png_write_chunk_data(png_ptr, (png_bytep)new_key, + (png_size_t)(key_len + 1)); + png_free(png_ptr, new_key); + + buf[0] = (png_byte)compression; + /* Write compression */ + png_write_chunk_data(png_ptr, (png_bytep)buf, (png_size_t)1); + /* Write the compressed data */ + png_write_compressed_data_out(png_ptr, &comp); + + /* Close the chunk */ + png_write_chunk_end(png_ptr); +} +#endif + +#ifdef PNG_WRITE_iTXt_SUPPORTED +/* Write an iTXt chunk */ +void /* PRIVATE */ +png_write_iTXt(png_structp png_ptr, int compression, png_charp key, + png_charp lang, png_charp lang_key, png_charp text) +{ + PNG_iTXt; + png_size_t lang_len, key_len, lang_key_len, text_len; + png_charp new_lang; + png_charp new_key = NULL; + png_byte cbuf[2]; + compression_state comp; + + png_debug(1, "in png_write_iTXt"); + + comp.num_output_ptr = 0; + comp.max_output_ptr = 0; + comp.output_ptr = NULL; + comp.input = NULL; + + if ((key_len = png_check_keyword(png_ptr, key, &new_key))==0) + return; + + if ((lang_len = png_check_keyword(png_ptr, lang, &new_lang))==0) + { + png_warning(png_ptr, "Empty language field in iTXt chunk"); + new_lang = NULL; + lang_len = 0; + } + + if (lang_key == NULL) + lang_key_len = 0; + else + lang_key_len = png_strlen(lang_key); + + if (text == NULL) + text_len = 0; + else + text_len = png_strlen(text); + + /* Compute the compressed data; do it now for the length */ + text_len = png_text_compress(png_ptr, text, text_len, compression-2, + &comp); + + + /* Make sure we include the compression flag, the compression byte, + * and the NULs after the key, lang, and lang_key parts */ + + png_write_chunk_start(png_ptr, (png_bytep)png_iTXt, + (png_uint_32)( + 5 /* comp byte, comp flag, terminators for key, lang and lang_key */ + + key_len + + lang_len + + lang_key_len + + text_len)); + + /* We leave it to the application to meet PNG-1.0 requirements on the + * contents of the text. PNG-1.0 through PNG-1.2 discourage the use of + * any non-Latin-1 characters except for NEWLINE. ISO PNG will forbid them. + * The NUL character is forbidden by PNG-1.0 through PNG-1.2 and ISO PNG. + */ + png_write_chunk_data(png_ptr, (png_bytep)new_key, + (png_size_t)(key_len + 1)); + + /* Set the compression flag */ + if (compression == PNG_ITXT_COMPRESSION_NONE || \ + compression == PNG_TEXT_COMPRESSION_NONE) + cbuf[0] = 0; + else /* compression == PNG_ITXT_COMPRESSION_zTXt */ + cbuf[0] = 1; + /* Set the compression method */ + cbuf[1] = 0; + png_write_chunk_data(png_ptr, cbuf, (png_size_t)2); + + cbuf[0] = 0; + png_write_chunk_data(png_ptr, (new_lang ? (png_bytep)new_lang : cbuf), + (png_size_t)(lang_len + 1)); + png_write_chunk_data(png_ptr, (lang_key ? (png_bytep)lang_key : cbuf), + (png_size_t)(lang_key_len + 1)); + png_write_compressed_data_out(png_ptr, &comp); + + png_write_chunk_end(png_ptr); + png_free(png_ptr, new_key); + png_free(png_ptr, new_lang); +} +#endif + +#ifdef PNG_WRITE_oFFs_SUPPORTED +/* Write the oFFs chunk */ +void /* PRIVATE */ +png_write_oFFs(png_structp png_ptr, png_int_32 x_offset, png_int_32 y_offset, + int unit_type) +{ + PNG_oFFs; + png_byte buf[9]; + + png_debug(1, "in png_write_oFFs"); + + if (unit_type >= PNG_OFFSET_LAST) + png_warning(png_ptr, "Unrecognized unit type for oFFs chunk"); + + png_save_int_32(buf, x_offset); + png_save_int_32(buf + 4, y_offset); + buf[8] = (png_byte)unit_type; + + png_write_chunk(png_ptr, (png_bytep)png_oFFs, buf, (png_size_t)9); +} +#endif +#ifdef PNG_WRITE_pCAL_SUPPORTED +/* Write the pCAL chunk (described in the PNG extensions document) */ +void /* PRIVATE */ +png_write_pCAL(png_structp png_ptr, png_charp purpose, png_int_32 X0, + png_int_32 X1, int type, int nparams, png_charp units, png_charpp params) +{ + PNG_pCAL; + png_size_t purpose_len, units_len, total_len; + png_uint_32p params_len; + png_byte buf[10]; + png_charp new_purpose; + int i; + + png_debug1(1, "in png_write_pCAL (%d parameters)", nparams); + + if (type >= PNG_EQUATION_LAST) + png_warning(png_ptr, "Unrecognized equation type for pCAL chunk"); + + purpose_len = png_check_keyword(png_ptr, purpose, &new_purpose) + 1; + png_debug1(3, "pCAL purpose length = %d", (int)purpose_len); + units_len = png_strlen(units) + (nparams == 0 ? 0 : 1); + png_debug1(3, "pCAL units length = %d", (int)units_len); + total_len = purpose_len + units_len + 10; + + params_len = (png_uint_32p)png_malloc(png_ptr, + (png_alloc_size_t)(nparams * png_sizeof(png_uint_32))); + + /* Find the length of each parameter, making sure we don't count the + null terminator for the last parameter. */ + for (i = 0; i < nparams; i++) + { + params_len[i] = png_strlen(params[i]) + (i == nparams - 1 ? 0 : 1); + png_debug2(3, "pCAL parameter %d length = %lu", i, + (unsigned long) params_len[i]); + total_len += (png_size_t)params_len[i]; + } + + png_debug1(3, "pCAL total length = %d", (int)total_len); + png_write_chunk_start(png_ptr, (png_bytep)png_pCAL, (png_uint_32)total_len); + png_write_chunk_data(png_ptr, (png_bytep)new_purpose, + (png_size_t)purpose_len); + png_save_int_32(buf, X0); + png_save_int_32(buf + 4, X1); + buf[8] = (png_byte)type; + buf[9] = (png_byte)nparams; + png_write_chunk_data(png_ptr, buf, (png_size_t)10); + png_write_chunk_data(png_ptr, (png_bytep)units, (png_size_t)units_len); + + png_free(png_ptr, new_purpose); + + for (i = 0; i < nparams; i++) + { + png_write_chunk_data(png_ptr, (png_bytep)params[i], + (png_size_t)params_len[i]); + } + + png_free(png_ptr, params_len); + png_write_chunk_end(png_ptr); +} +#endif + +#ifdef PNG_WRITE_sCAL_SUPPORTED +/* Write the sCAL chunk */ +#if defined(PNG_FLOATING_POINT_SUPPORTED) && defined(PNG_STDIO_SUPPORTED) +void /* PRIVATE */ +png_write_sCAL(png_structp png_ptr, int unit, double width, double height) +{ + PNG_sCAL; + char buf[64]; + png_size_t total_len; + + png_debug(1, "in png_write_sCAL"); + + buf[0] = (char)unit; + png_snprintf(buf + 1, 63, "%12.12e", width); + total_len = 1 + png_strlen(buf + 1) + 1; + png_snprintf(buf + total_len, 64-total_len, "%12.12e", height); + total_len += png_strlen(buf + total_len); + + png_debug1(3, "sCAL total length = %u", (unsigned int)total_len); + png_write_chunk(png_ptr, (png_bytep)png_sCAL, (png_bytep)buf, total_len); +} +#else +#ifdef PNG_FIXED_POINT_SUPPORTED +void /* PRIVATE */ +png_write_sCAL_s(png_structp png_ptr, int unit, png_charp width, + png_charp height) +{ + PNG_sCAL; + png_byte buf[64]; + png_size_t wlen, hlen, total_len; + + png_debug(1, "in png_write_sCAL_s"); + + wlen = png_strlen(width); + hlen = png_strlen(height); + total_len = wlen + hlen + 2; + if (total_len > 64) + { + png_warning(png_ptr, "Can't write sCAL (buffer too small)"); + return; + } + + buf[0] = (png_byte)unit; + png_memcpy(buf + 1, width, wlen + 1); /* Append the '\0' here */ + png_memcpy(buf + wlen + 2, height, hlen); /* Do NOT append the '\0' here */ + + png_debug1(3, "sCAL total length = %u", (unsigned int)total_len); + png_write_chunk(png_ptr, (png_bytep)png_sCAL, buf, total_len); +} +#endif +#endif +#endif + +#ifdef PNG_WRITE_pHYs_SUPPORTED +/* Write the pHYs chunk */ +void /* PRIVATE */ +png_write_pHYs(png_structp png_ptr, png_uint_32 x_pixels_per_unit, + png_uint_32 y_pixels_per_unit, + int unit_type) +{ + PNG_pHYs; + png_byte buf[9]; + + png_debug(1, "in png_write_pHYs"); + + if (unit_type >= PNG_RESOLUTION_LAST) + png_warning(png_ptr, "Unrecognized unit type for pHYs chunk"); + + png_save_uint_32(buf, x_pixels_per_unit); + png_save_uint_32(buf + 4, y_pixels_per_unit); + buf[8] = (png_byte)unit_type; + + png_write_chunk(png_ptr, (png_bytep)png_pHYs, buf, (png_size_t)9); +} +#endif + +#ifdef PNG_WRITE_tIME_SUPPORTED +/* Write the tIME chunk. Use either png_convert_from_struct_tm() + * or png_convert_from_time_t(), or fill in the structure yourself. + */ +void /* PRIVATE */ +png_write_tIME(png_structp png_ptr, png_timep mod_time) +{ + PNG_tIME; + png_byte buf[7]; + + png_debug(1, "in png_write_tIME"); + + if (mod_time->month > 12 || mod_time->month < 1 || + mod_time->day > 31 || mod_time->day < 1 || + mod_time->hour > 23 || mod_time->second > 60) + { + png_warning(png_ptr, "Invalid time specified for tIME chunk"); + return; + } + + png_save_uint_16(buf, mod_time->year); + buf[2] = mod_time->month; + buf[3] = mod_time->day; + buf[4] = mod_time->hour; + buf[5] = mod_time->minute; + buf[6] = mod_time->second; + + png_write_chunk(png_ptr, (png_bytep)png_tIME, buf, (png_size_t)7); +} +#endif + +/* Initializes the row writing capability of libpng */ +void /* PRIVATE */ +png_write_start_row(png_structp png_ptr) +{ +#ifdef PNG_WRITE_INTERLACING_SUPPORTED + /* Arrays to facilitate easy interlacing - use pass (0 - 6) as index */ + + /* Start of interlace block */ + int png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0}; + + /* Offset to next interlace block */ + int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1}; + + /* Start of interlace block in the y direction */ + int png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1}; + + /* Offset to next interlace block in the y direction */ + int png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2}; +#endif + + png_size_t buf_size; + + png_debug(1, "in png_write_start_row"); + + buf_size = (png_size_t)(PNG_ROWBYTES( + png_ptr->usr_channels*png_ptr->usr_bit_depth, png_ptr->width) + 1); + + /* Set up row buffer */ + png_ptr->row_buf = (png_bytep)png_malloc(png_ptr, + (png_alloc_size_t)buf_size); + png_ptr->row_buf[0] = PNG_FILTER_VALUE_NONE; + +#ifdef PNG_WRITE_FILTER_SUPPORTED + /* Set up filtering buffer, if using this filter */ + if (png_ptr->do_filter & PNG_FILTER_SUB) + { + png_ptr->sub_row = (png_bytep)png_malloc(png_ptr, + (png_alloc_size_t)(png_ptr->rowbytes + 1)); + png_ptr->sub_row[0] = PNG_FILTER_VALUE_SUB; + } + + /* We only need to keep the previous row if we are using one of these. */ + if (png_ptr->do_filter & (PNG_FILTER_AVG | PNG_FILTER_UP | PNG_FILTER_PAETH)) + { + /* Set up previous row buffer */ + png_ptr->prev_row = (png_bytep)png_calloc(png_ptr, + (png_alloc_size_t)buf_size); + + if (png_ptr->do_filter & PNG_FILTER_UP) + { + png_ptr->up_row = (png_bytep)png_malloc(png_ptr, + (png_size_t)(png_ptr->rowbytes + 1)); + png_ptr->up_row[0] = PNG_FILTER_VALUE_UP; + } + + if (png_ptr->do_filter & PNG_FILTER_AVG) + { + png_ptr->avg_row = (png_bytep)png_malloc(png_ptr, + (png_alloc_size_t)(png_ptr->rowbytes + 1)); + png_ptr->avg_row[0] = PNG_FILTER_VALUE_AVG; + } + + if (png_ptr->do_filter & PNG_FILTER_PAETH) + { + png_ptr->paeth_row = (png_bytep)png_malloc(png_ptr, + (png_size_t)(png_ptr->rowbytes + 1)); + png_ptr->paeth_row[0] = PNG_FILTER_VALUE_PAETH; + } + } +#endif /* PNG_WRITE_FILTER_SUPPORTED */ + +#ifdef PNG_WRITE_INTERLACING_SUPPORTED + /* If interlaced, we need to set up width and height of pass */ + if (png_ptr->interlaced) + { + if (!(png_ptr->transformations & PNG_INTERLACE)) + { + png_ptr->num_rows = (png_ptr->height + png_pass_yinc[0] - 1 - + png_pass_ystart[0]) / png_pass_yinc[0]; + png_ptr->usr_width = (png_ptr->width + png_pass_inc[0] - 1 - + png_pass_start[0]) / png_pass_inc[0]; + } + else + { + png_ptr->num_rows = png_ptr->height; + png_ptr->usr_width = png_ptr->width; + } + } + else +#endif + { + png_ptr->num_rows = png_ptr->height; + png_ptr->usr_width = png_ptr->width; + } + png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size; + png_ptr->zstream.next_out = png_ptr->zbuf; +} + +/* Internal use only. Called when finished processing a row of data. */ +void /* PRIVATE */ +png_write_finish_row(png_structp png_ptr) +{ +#ifdef PNG_WRITE_INTERLACING_SUPPORTED + /* Arrays to facilitate easy interlacing - use pass (0 - 6) as index */ + + /* Start of interlace block */ + int png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0}; + + /* Offset to next interlace block */ + int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1}; + + /* Start of interlace block in the y direction */ + int png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1}; + + /* Offset to next interlace block in the y direction */ + int png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2}; +#endif + + int ret; + + png_debug(1, "in png_write_finish_row"); + + /* Next row */ + png_ptr->row_number++; + + /* See if we are done */ + if (png_ptr->row_number < png_ptr->num_rows) + return; + +#ifdef PNG_WRITE_INTERLACING_SUPPORTED + /* If interlaced, go to next pass */ + if (png_ptr->interlaced) + { + png_ptr->row_number = 0; + if (png_ptr->transformations & PNG_INTERLACE) + { + png_ptr->pass++; + } + else + { + /* Loop until we find a non-zero width or height pass */ + do + { + png_ptr->pass++; + if (png_ptr->pass >= 7) + break; + png_ptr->usr_width = (png_ptr->width + + png_pass_inc[png_ptr->pass] - 1 - + png_pass_start[png_ptr->pass]) / + png_pass_inc[png_ptr->pass]; + png_ptr->num_rows = (png_ptr->height + + png_pass_yinc[png_ptr->pass] - 1 - + png_pass_ystart[png_ptr->pass]) / + png_pass_yinc[png_ptr->pass]; + if (png_ptr->transformations & PNG_INTERLACE) + break; + } while (png_ptr->usr_width == 0 || png_ptr->num_rows == 0); + + } + + /* Reset the row above the image for the next pass */ + if (png_ptr->pass < 7) + { + if (png_ptr->prev_row != NULL) + png_memset(png_ptr->prev_row, 0, + (png_size_t)(PNG_ROWBYTES(png_ptr->usr_channels* + png_ptr->usr_bit_depth, png_ptr->width)) + 1); + return; + } + } +#endif + + /* If we get here, we've just written the last row, so we need + to flush the compressor */ + do + { + /* Tell the compressor we are done */ + ret = deflate(&png_ptr->zstream, Z_FINISH); + /* Check for an error */ + if (ret == Z_OK) + { + /* Check to see if we need more room */ + if (!(png_ptr->zstream.avail_out)) + { + png_write_IDAT(png_ptr, png_ptr->zbuf, png_ptr->zbuf_size); + png_ptr->zstream.next_out = png_ptr->zbuf; + png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size; + } + } + else if (ret != Z_STREAM_END) + { + if (png_ptr->zstream.msg != NULL) + png_error(png_ptr, png_ptr->zstream.msg); + else + png_error(png_ptr, "zlib error"); + } + } while (ret != Z_STREAM_END); + + /* Write any extra space */ + if (png_ptr->zstream.avail_out < png_ptr->zbuf_size) + { + png_write_IDAT(png_ptr, png_ptr->zbuf, png_ptr->zbuf_size - + png_ptr->zstream.avail_out); + } + + deflateReset(&png_ptr->zstream); + png_ptr->zstream.data_type = Z_BINARY; +} + +#ifdef PNG_WRITE_INTERLACING_SUPPORTED +/* Pick out the correct pixels for the interlace pass. + * The basic idea here is to go through the row with a source + * pointer and a destination pointer (sp and dp), and copy the + * correct pixels for the pass. As the row gets compacted, + * sp will always be >= dp, so we should never overwrite anything. + * See the default: case for the easiest code to understand. + */ +void /* PRIVATE */ +png_do_write_interlace(png_row_infop row_info, png_bytep row, int pass) +{ + /* Arrays to facilitate easy interlacing - use pass (0 - 6) as index */ + + /* Start of interlace block */ + int png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0}; + + /* Offset to next interlace block */ + int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1}; + + png_debug(1, "in png_do_write_interlace"); + + /* We don't have to do anything on the last pass (6) */ + if (pass < 6) + { + /* Each pixel depth is handled separately */ + switch (row_info->pixel_depth) + { + case 1: + { + png_bytep sp; + png_bytep dp; + int shift; + int d; + int value; + png_uint_32 i; + png_uint_32 row_width = row_info->width; + + dp = row; + d = 0; + shift = 7; + for (i = png_pass_start[pass]; i < row_width; + i += png_pass_inc[pass]) + { + sp = row + (png_size_t)(i >> 3); + value = (int)(*sp >> (7 - (int)(i & 0x07))) & 0x01; + d |= (value << shift); + + if (shift == 0) + { + shift = 7; + *dp++ = (png_byte)d; + d = 0; + } + else + shift--; + + } + if (shift != 7) + *dp = (png_byte)d; + break; + } + case 2: + { + png_bytep sp; + png_bytep dp; + int shift; + int d; + int value; + png_uint_32 i; + png_uint_32 row_width = row_info->width; + + dp = row; + shift = 6; + d = 0; + for (i = png_pass_start[pass]; i < row_width; + i += png_pass_inc[pass]) + { + sp = row + (png_size_t)(i >> 2); + value = (*sp >> ((3 - (int)(i & 0x03)) << 1)) & 0x03; + d |= (value << shift); + + if (shift == 0) + { + shift = 6; + *dp++ = (png_byte)d; + d = 0; + } + else + shift -= 2; + } + if (shift != 6) + *dp = (png_byte)d; + break; + } + case 4: + { + png_bytep sp; + png_bytep dp; + int shift; + int d; + int value; + png_uint_32 i; + png_uint_32 row_width = row_info->width; + + dp = row; + shift = 4; + d = 0; + for (i = png_pass_start[pass]; i < row_width; + i += png_pass_inc[pass]) + { + sp = row + (png_size_t)(i >> 1); + value = (*sp >> ((1 - (int)(i & 0x01)) << 2)) & 0x0f; + d |= (value << shift); + + if (shift == 0) + { + shift = 4; + *dp++ = (png_byte)d; + d = 0; + } + else + shift -= 4; + } + if (shift != 4) + *dp = (png_byte)d; + break; + } + default: + { + png_bytep sp; + png_bytep dp; + png_uint_32 i; + png_uint_32 row_width = row_info->width; + png_size_t pixel_bytes; + + /* Start at the beginning */ + dp = row; + /* Find out how many bytes each pixel takes up */ + pixel_bytes = (row_info->pixel_depth >> 3); + /* Loop through the row, only looking at the pixels that + matter */ + for (i = png_pass_start[pass]; i < row_width; + i += png_pass_inc[pass]) + { + /* Find out where the original pixel is */ + sp = row + (png_size_t)i * pixel_bytes; + /* Move the pixel */ + if (dp != sp) + png_memcpy(dp, sp, pixel_bytes); + /* Next pixel */ + dp += pixel_bytes; + } + break; + } + } + /* Set new row width */ + row_info->width = (row_info->width + + png_pass_inc[pass] - 1 - + png_pass_start[pass]) / + png_pass_inc[pass]; + row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth, + row_info->width); + } +} +#endif + +/* This filters the row, chooses which filter to use, if it has not already + * been specified by the application, and then writes the row out with the + * chosen filter. + */ +#define PNG_MAXSUM (((png_uint_32)(-1)) >> 1) +#define PNG_HISHIFT 10 +#define PNG_LOMASK ((png_uint_32)0xffffL) +#define PNG_HIMASK ((png_uint_32)(~PNG_LOMASK >> PNG_HISHIFT)) +void /* PRIVATE */ +png_write_find_filter(png_structp png_ptr, png_row_infop row_info) +{ + png_bytep best_row; +#ifdef PNG_WRITE_FILTER_SUPPORTED + png_bytep prev_row, row_buf; + png_uint_32 mins, bpp; + png_byte filter_to_do = png_ptr->do_filter; + png_uint_32 row_bytes = row_info->rowbytes; +#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED + int num_p_filters = (int)png_ptr->num_prev_filters; +#endif + + png_debug(1, "in png_write_find_filter"); + +#ifndef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED + if (png_ptr->row_number == 0 && filter_to_do == PNG_ALL_FILTERS) + { + /* These will never be selected so we need not test them. */ + filter_to_do &= ~(PNG_FILTER_UP | PNG_FILTER_PAETH); + } +#endif + + /* Find out how many bytes offset each pixel is */ + bpp = (row_info->pixel_depth + 7) >> 3; + + prev_row = png_ptr->prev_row; +#endif + best_row = png_ptr->row_buf; +#ifdef PNG_WRITE_FILTER_SUPPORTED + row_buf = best_row; + mins = PNG_MAXSUM; + + /* The prediction method we use is to find which method provides the + * smallest value when summing the absolute values of the distances + * from zero, using anything >= 128 as negative numbers. This is known + * as the "minimum sum of absolute differences" heuristic. Other + * heuristics are the "weighted minimum sum of absolute differences" + * (experimental and can in theory improve compression), and the "zlib + * predictive" method (not implemented yet), which does test compressions + * of lines using different filter methods, and then chooses the + * (series of) filter(s) that give minimum compressed data size (VERY + * computationally expensive). + * + * GRR 980525: consider also + * (1) minimum sum of absolute differences from running average (i.e., + * keep running sum of non-absolute differences & count of bytes) + * [track dispersion, too? restart average if dispersion too large?] + * (1b) minimum sum of absolute differences from sliding average, probably + * with window size <= deflate window (usually 32K) + * (2) minimum sum of squared differences from zero or running average + * (i.e., ~ root-mean-square approach) + */ + + + /* We don't need to test the 'no filter' case if this is the only filter + * that has been chosen, as it doesn't actually do anything to the data. + */ + if ((filter_to_do & PNG_FILTER_NONE) && + filter_to_do != PNG_FILTER_NONE) + { + png_bytep rp; + png_uint_32 sum = 0; + png_uint_32 i; + int v; + + for (i = 0, rp = row_buf + 1; i < row_bytes; i++, rp++) + { + v = *rp; + sum += (v < 128) ? v : 256 - v; + } + +#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED + if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED) + { + png_uint_32 sumhi, sumlo; + int j; + sumlo = sum & PNG_LOMASK; + sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK; /* Gives us some footroom */ + + /* Reduce the sum if we match any of the previous rows */ + for (j = 0; j < num_p_filters; j++) + { + if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_NONE) + { + sumlo = (sumlo * png_ptr->filter_weights[j]) >> + PNG_WEIGHT_SHIFT; + sumhi = (sumhi * png_ptr->filter_weights[j]) >> + PNG_WEIGHT_SHIFT; + } + } + + /* Factor in the cost of this filter (this is here for completeness, + * but it makes no sense to have a "cost" for the NONE filter, as + * it has the minimum possible computational cost - none). + */ + sumlo = (sumlo * png_ptr->filter_costs[PNG_FILTER_VALUE_NONE]) >> + PNG_COST_SHIFT; + sumhi = (sumhi * png_ptr->filter_costs[PNG_FILTER_VALUE_NONE]) >> + PNG_COST_SHIFT; + + if (sumhi > PNG_HIMASK) + sum = PNG_MAXSUM; + else + sum = (sumhi << PNG_HISHIFT) + sumlo; + } +#endif + mins = sum; + } + + /* Sub filter */ + if (filter_to_do == PNG_FILTER_SUB) + /* It's the only filter so no testing is needed */ + { + png_bytep rp, lp, dp; + png_uint_32 i; + for (i = 0, rp = row_buf + 1, dp = png_ptr->sub_row + 1; i < bpp; + i++, rp++, dp++) + { + *dp = *rp; + } + for (lp = row_buf + 1; i < row_bytes; + i++, rp++, lp++, dp++) + { + *dp = (png_byte)(((int)*rp - (int)*lp) & 0xff); + } + best_row = png_ptr->sub_row; + } + + else if (filter_to_do & PNG_FILTER_SUB) + { + png_bytep rp, dp, lp; + png_uint_32 sum = 0, lmins = mins; + png_uint_32 i; + int v; + +#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED + /* We temporarily increase the "minimum sum" by the factor we + * would reduce the sum of this filter, so that we can do the + * early exit comparison without scaling the sum each time. + */ + if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED) + { + int j; + png_uint_32 lmhi, lmlo; + lmlo = lmins & PNG_LOMASK; + lmhi = (lmins >> PNG_HISHIFT) & PNG_HIMASK; + + for (j = 0; j < num_p_filters; j++) + { + if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_SUB) + { + lmlo = (lmlo * png_ptr->inv_filter_weights[j]) >> + PNG_WEIGHT_SHIFT; + lmhi = (lmhi * png_ptr->inv_filter_weights[j]) >> + PNG_WEIGHT_SHIFT; + } + } + + lmlo = (lmlo * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_SUB]) >> + PNG_COST_SHIFT; + lmhi = (lmhi * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_SUB]) >> + PNG_COST_SHIFT; + + if (lmhi > PNG_HIMASK) + lmins = PNG_MAXSUM; + else + lmins = (lmhi << PNG_HISHIFT) + lmlo; + } +#endif + + for (i = 0, rp = row_buf + 1, dp = png_ptr->sub_row + 1; i < bpp; + i++, rp++, dp++) + { + v = *dp = *rp; + + sum += (v < 128) ? v : 256 - v; + } + for (lp = row_buf + 1; i < row_bytes; + i++, rp++, lp++, dp++) + { + v = *dp = (png_byte)(((int)*rp - (int)*lp) & 0xff); + + sum += (v < 128) ? v : 256 - v; + + if (sum > lmins) /* We are already worse, don't continue. */ + break; + } + +#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED + if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED) + { + int j; + png_uint_32 sumhi, sumlo; + sumlo = sum & PNG_LOMASK; + sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK; + + for (j = 0; j < num_p_filters; j++) + { + if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_SUB) + { + sumlo = (sumlo * png_ptr->inv_filter_weights[j]) >> + PNG_WEIGHT_SHIFT; + sumhi = (sumhi * png_ptr->inv_filter_weights[j]) >> + PNG_WEIGHT_SHIFT; + } + } + + sumlo = (sumlo * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_SUB]) >> + PNG_COST_SHIFT; + sumhi = (sumhi * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_SUB]) >> + PNG_COST_SHIFT; + + if (sumhi > PNG_HIMASK) + sum = PNG_MAXSUM; + else + sum = (sumhi << PNG_HISHIFT) + sumlo; + } +#endif + + if (sum < mins) + { + mins = sum; + best_row = png_ptr->sub_row; + } + } + + /* Up filter */ + if (filter_to_do == PNG_FILTER_UP) + { + png_bytep rp, dp, pp; + png_uint_32 i; + + for (i = 0, rp = row_buf + 1, dp = png_ptr->up_row + 1, + pp = prev_row + 1; i < row_bytes; + i++, rp++, pp++, dp++) + { + *dp = (png_byte)(((int)*rp - (int)*pp) & 0xff); + } + best_row = png_ptr->up_row; + } + + else if (filter_to_do & PNG_FILTER_UP) + { + png_bytep rp, dp, pp; + png_uint_32 sum = 0, lmins = mins; + png_uint_32 i; + int v; + + +#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED + if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED) + { + int j; + png_uint_32 lmhi, lmlo; + lmlo = lmins & PNG_LOMASK; + lmhi = (lmins >> PNG_HISHIFT) & PNG_HIMASK; + + for (j = 0; j < num_p_filters; j++) + { + if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_UP) + { + lmlo = (lmlo * png_ptr->inv_filter_weights[j]) >> + PNG_WEIGHT_SHIFT; + lmhi = (lmhi * png_ptr->inv_filter_weights[j]) >> + PNG_WEIGHT_SHIFT; + } + } + + lmlo = (lmlo * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_UP]) >> + PNG_COST_SHIFT; + lmhi = (lmhi * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_UP]) >> + PNG_COST_SHIFT; + + if (lmhi > PNG_HIMASK) + lmins = PNG_MAXSUM; + else + lmins = (lmhi << PNG_HISHIFT) + lmlo; + } +#endif + + for (i = 0, rp = row_buf + 1, dp = png_ptr->up_row + 1, + pp = prev_row + 1; i < row_bytes; i++) + { + v = *dp++ = (png_byte)(((int)*rp++ - (int)*pp++) & 0xff); + + sum += (v < 128) ? v : 256 - v; + + if (sum > lmins) /* We are already worse, don't continue. */ + break; + } + +#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED + if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED) + { + int j; + png_uint_32 sumhi, sumlo; + sumlo = sum & PNG_LOMASK; + sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK; + + for (j = 0; j < num_p_filters; j++) + { + if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_UP) + { + sumlo = (sumlo * png_ptr->filter_weights[j]) >> + PNG_WEIGHT_SHIFT; + sumhi = (sumhi * png_ptr->filter_weights[j]) >> + PNG_WEIGHT_SHIFT; + } + } + + sumlo = (sumlo * png_ptr->filter_costs[PNG_FILTER_VALUE_UP]) >> + PNG_COST_SHIFT; + sumhi = (sumhi * png_ptr->filter_costs[PNG_FILTER_VALUE_UP]) >> + PNG_COST_SHIFT; + + if (sumhi > PNG_HIMASK) + sum = PNG_MAXSUM; + else + sum = (sumhi << PNG_HISHIFT) + sumlo; + } +#endif + + if (sum < mins) + { + mins = sum; + best_row = png_ptr->up_row; + } + } + + /* Avg filter */ + if (filter_to_do == PNG_FILTER_AVG) + { + png_bytep rp, dp, pp, lp; + png_uint_32 i; + for (i = 0, rp = row_buf + 1, dp = png_ptr->avg_row + 1, + pp = prev_row + 1; i < bpp; i++) + { + *dp++ = (png_byte)(((int)*rp++ - ((int)*pp++ / 2)) & 0xff); + } + for (lp = row_buf + 1; i < row_bytes; i++) + { + *dp++ = (png_byte)(((int)*rp++ - (((int)*pp++ + (int)*lp++) / 2)) + & 0xff); + } + best_row = png_ptr->avg_row; + } + + else if (filter_to_do & PNG_FILTER_AVG) + { + png_bytep rp, dp, pp, lp; + png_uint_32 sum = 0, lmins = mins; + png_uint_32 i; + int v; + +#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED + if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED) + { + int j; + png_uint_32 lmhi, lmlo; + lmlo = lmins & PNG_LOMASK; + lmhi = (lmins >> PNG_HISHIFT) & PNG_HIMASK; + + for (j = 0; j < num_p_filters; j++) + { + if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_AVG) + { + lmlo = (lmlo * png_ptr->inv_filter_weights[j]) >> + PNG_WEIGHT_SHIFT; + lmhi = (lmhi * png_ptr->inv_filter_weights[j]) >> + PNG_WEIGHT_SHIFT; + } + } + + lmlo = (lmlo * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_AVG]) >> + PNG_COST_SHIFT; + lmhi = (lmhi * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_AVG]) >> + PNG_COST_SHIFT; + + if (lmhi > PNG_HIMASK) + lmins = PNG_MAXSUM; + else + lmins = (lmhi << PNG_HISHIFT) + lmlo; + } +#endif + + for (i = 0, rp = row_buf + 1, dp = png_ptr->avg_row + 1, + pp = prev_row + 1; i < bpp; i++) + { + v = *dp++ = (png_byte)(((int)*rp++ - ((int)*pp++ / 2)) & 0xff); + + sum += (v < 128) ? v : 256 - v; + } + for (lp = row_buf + 1; i < row_bytes; i++) + { + v = *dp++ = + (png_byte)(((int)*rp++ - (((int)*pp++ + (int)*lp++) / 2)) & 0xff); + + sum += (v < 128) ? v : 256 - v; + + if (sum > lmins) /* We are already worse, don't continue. */ + break; + } + +#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED + if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED) + { + int j; + png_uint_32 sumhi, sumlo; + sumlo = sum & PNG_LOMASK; + sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK; + + for (j = 0; j < num_p_filters; j++) + { + if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_NONE) + { + sumlo = (sumlo * png_ptr->filter_weights[j]) >> + PNG_WEIGHT_SHIFT; + sumhi = (sumhi * png_ptr->filter_weights[j]) >> + PNG_WEIGHT_SHIFT; + } + } + + sumlo = (sumlo * png_ptr->filter_costs[PNG_FILTER_VALUE_AVG]) >> + PNG_COST_SHIFT; + sumhi = (sumhi * png_ptr->filter_costs[PNG_FILTER_VALUE_AVG]) >> + PNG_COST_SHIFT; + + if (sumhi > PNG_HIMASK) + sum = PNG_MAXSUM; + else + sum = (sumhi << PNG_HISHIFT) + sumlo; + } +#endif + + if (sum < mins) + { + mins = sum; + best_row = png_ptr->avg_row; + } + } + + /* Paeth filter */ + if (filter_to_do == PNG_FILTER_PAETH) + { + png_bytep rp, dp, pp, cp, lp; + png_uint_32 i; + for (i = 0, rp = row_buf + 1, dp = png_ptr->paeth_row + 1, + pp = prev_row + 1; i < bpp; i++) + { + *dp++ = (png_byte)(((int)*rp++ - (int)*pp++) & 0xff); + } + + for (lp = row_buf + 1, cp = prev_row + 1; i < row_bytes; i++) + { + int a, b, c, pa, pb, pc, p; + + b = *pp++; + c = *cp++; + a = *lp++; + + p = b - c; + pc = a - c; + +#ifdef PNG_USE_ABS + pa = abs(p); + pb = abs(pc); + pc = abs(p + pc); +#else + pa = p < 0 ? -p : p; + pb = pc < 0 ? -pc : pc; + pc = (p + pc) < 0 ? -(p + pc) : p + pc; +#endif + + p = (pa <= pb && pa <=pc) ? a : (pb <= pc) ? b : c; + + *dp++ = (png_byte)(((int)*rp++ - p) & 0xff); + } + best_row = png_ptr->paeth_row; + } + + else if (filter_to_do & PNG_FILTER_PAETH) + { + png_bytep rp, dp, pp, cp, lp; + png_uint_32 sum = 0, lmins = mins; + png_uint_32 i; + int v; + +#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED + if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED) + { + int j; + png_uint_32 lmhi, lmlo; + lmlo = lmins & PNG_LOMASK; + lmhi = (lmins >> PNG_HISHIFT) & PNG_HIMASK; + + for (j = 0; j < num_p_filters; j++) + { + if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_PAETH) + { + lmlo = (lmlo * png_ptr->inv_filter_weights[j]) >> + PNG_WEIGHT_SHIFT; + lmhi = (lmhi * png_ptr->inv_filter_weights[j]) >> + PNG_WEIGHT_SHIFT; + } + } + + lmlo = (lmlo * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_PAETH]) >> + PNG_COST_SHIFT; + lmhi = (lmhi * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_PAETH]) >> + PNG_COST_SHIFT; + + if (lmhi > PNG_HIMASK) + lmins = PNG_MAXSUM; + else + lmins = (lmhi << PNG_HISHIFT) + lmlo; + } +#endif + + for (i = 0, rp = row_buf + 1, dp = png_ptr->paeth_row + 1, + pp = prev_row + 1; i < bpp; i++) + { + v = *dp++ = (png_byte)(((int)*rp++ - (int)*pp++) & 0xff); + + sum += (v < 128) ? v : 256 - v; + } + + for (lp = row_buf + 1, cp = prev_row + 1; i < row_bytes; i++) + { + int a, b, c, pa, pb, pc, p; + + b = *pp++; + c = *cp++; + a = *lp++; + +#ifndef PNG_SLOW_PAETH + p = b - c; + pc = a - c; +#ifdef PNG_USE_ABS + pa = abs(p); + pb = abs(pc); + pc = abs(p + pc); +#else + pa = p < 0 ? -p : p; + pb = pc < 0 ? -pc : pc; + pc = (p + pc) < 0 ? -(p + pc) : p + pc; +#endif + p = (pa <= pb && pa <=pc) ? a : (pb <= pc) ? b : c; +#else /* PNG_SLOW_PAETH */ + p = a + b - c; + pa = abs(p - a); + pb = abs(p - b); + pc = abs(p - c); + if (pa <= pb && pa <= pc) + p = a; + else if (pb <= pc) + p = b; + else + p = c; +#endif /* PNG_SLOW_PAETH */ + + v = *dp++ = (png_byte)(((int)*rp++ - p) & 0xff); + + sum += (v < 128) ? v : 256 - v; + + if (sum > lmins) /* We are already worse, don't continue. */ + break; + } + +#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED + if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED) + { + int j; + png_uint_32 sumhi, sumlo; + sumlo = sum & PNG_LOMASK; + sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK; + + for (j = 0; j < num_p_filters; j++) + { + if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_PAETH) + { + sumlo = (sumlo * png_ptr->filter_weights[j]) >> + PNG_WEIGHT_SHIFT; + sumhi = (sumhi * png_ptr->filter_weights[j]) >> + PNG_WEIGHT_SHIFT; + } + } + + sumlo = (sumlo * png_ptr->filter_costs[PNG_FILTER_VALUE_PAETH]) >> + PNG_COST_SHIFT; + sumhi = (sumhi * png_ptr->filter_costs[PNG_FILTER_VALUE_PAETH]) >> + PNG_COST_SHIFT; + + if (sumhi > PNG_HIMASK) + sum = PNG_MAXSUM; + else + sum = (sumhi << PNG_HISHIFT) + sumlo; + } +#endif + + if (sum < mins) + { + best_row = png_ptr->paeth_row; + } + } +#endif /* PNG_WRITE_FILTER_SUPPORTED */ + /* Do the actual writing of the filtered row data from the chosen filter. */ + + png_write_filtered_row(png_ptr, best_row); + +#ifdef PNG_WRITE_FILTER_SUPPORTED +#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED + /* Save the type of filter we picked this time for future calculations */ + if (png_ptr->num_prev_filters > 0) + { + int j; + for (j = 1; j < num_p_filters; j++) + { + png_ptr->prev_filters[j] = png_ptr->prev_filters[j - 1]; + } + png_ptr->prev_filters[j] = best_row[0]; + } +#endif +#endif /* PNG_WRITE_FILTER_SUPPORTED */ +} + + +/* Do the actual writing of a previously filtered row. */ +void /* PRIVATE */ +png_write_filtered_row(png_structp png_ptr, png_bytep filtered_row) +{ + png_debug(1, "in png_write_filtered_row"); + + png_debug1(2, "filter = %d", filtered_row[0]); + /* Set up the zlib input buffer */ + + png_ptr->zstream.next_in = filtered_row; + png_ptr->zstream.avail_in = (uInt)png_ptr->row_info.rowbytes + 1; + /* Repeat until we have compressed all the data */ + do + { + int ret; /* Return of zlib */ + + /* Compress the data */ + ret = deflate(&png_ptr->zstream, Z_NO_FLUSH); + /* Check for compression errors */ + if (ret != Z_OK) + { + if (png_ptr->zstream.msg != NULL) + png_error(png_ptr, png_ptr->zstream.msg); + else + png_error(png_ptr, "zlib error"); + } + + /* See if it is time to write another IDAT */ + if (!(png_ptr->zstream.avail_out)) + { + /* Write the IDAT and reset the zlib output buffer */ + png_write_IDAT(png_ptr, png_ptr->zbuf, png_ptr->zbuf_size); + png_ptr->zstream.next_out = png_ptr->zbuf; + png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size; + } + /* Repeat until all data has been compressed */ + } while (png_ptr->zstream.avail_in); + + /* Swap the current and previous rows */ + if (png_ptr->prev_row != NULL) + { + png_bytep tptr; + + tptr = png_ptr->prev_row; + png_ptr->prev_row = png_ptr->row_buf; + png_ptr->row_buf = tptr; + } + + /* Finish row - updates counters and flushes zlib if last row */ + png_write_finish_row(png_ptr); + +#ifdef PNG_WRITE_FLUSH_SUPPORTED + png_ptr->flush_rows++; + + if (png_ptr->flush_dist > 0 && + png_ptr->flush_rows >= png_ptr->flush_dist) + { + png_write_flush(png_ptr); + } +#endif +} +#endif /* PNG_WRITE_SUPPORTED */ -- 2.43.0