2 /* pngpriv.h - private declarations for use inside libpng
4 * For conditions of distribution and use, see copyright notice in png.h
5 * Copyright (c) 1998-2011 Glenn Randers-Pehrson
6 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
7 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
9 * Last changed in libpng 1.5.7 [December 15, 2011]
11 * This code is released under the libpng license.
12 * For conditions of distribution and use, see the disclaimer
13 * and license in png.h
16 /* The symbols declared in this file (including the functions declared
17 * as PNG_EXTERN) are PRIVATE. They are not part of the libpng public
18 * interface, and are not recommended for use by regular applications.
19 * Some of them may become public in the future; others may stay private,
20 * change in an incompatible way, or even disappear.
21 * Although the libpng users are not forbidden to include this header,
22 * they should be well aware of the issues that may arise from doing so.
28 /* Feature Test Macros. The following are defined here to ensure that correctly
29 * implemented libraries reveal the APIs libpng needs to build and hide those
30 * that are not needed and potentially damaging to the compilation.
32 * Feature Test Macros must be defined before any system header is included (see
33 * POSIX 1003.1 2.8.2 "POSIX Symbols."
35 * These macros only have an effect if the operating system supports either
36 * POSIX 1003.1 or C99, or both. On other operating systems (particularly
37 * Windows/Visual Studio) there is no effect; the OS specific tests below are
38 * still required (as of 2011-05-02.)
40 #define _POSIX_SOURCE 1 /* Just the POSIX 1003.1 and C89 APIs */
42 /* This is required for the definition of abort(), used as a last ditch
43 * error handler when all else fails.
47 /* This is used to find 'offsetof', used below for alignment tests. */
50 #define PNGLIB_BUILD /*libpng is being built, not used*/
52 #ifdef PNG_USER_CONFIG
54 /* These should have been defined in pngusr.h */
55 # ifndef PNG_USER_PRIVATEBUILD
56 # define PNG_USER_PRIVATEBUILD "Custom libpng build"
58 # ifndef PNG_USER_DLLFNAME_POSTFIX
59 # define PNG_USER_DLLFNAME_POSTFIX "Cb"
63 /* Is this a build of a DLL where compilation of the object modules requires
64 * different preprocessor settings to those required for a simple library? If
65 * so PNG_BUILD_DLL must be set.
67 * If libpng is used inside a DLL but that DLL does not export the libpng APIs
68 * PNG_BUILD_DLL must not be set. To avoid the code below kicking in build a
69 * static library of libpng then link the DLL against that.
73 /* This is set by libtool when files are compiled for a DLL; libtool
74 * always compiles twice, even on systems where it isn't necessary. Set
75 * PNG_BUILD_DLL in case it is necessary:
77 # define PNG_BUILD_DLL
80 /* This is set by the Microsoft Visual Studio IDE in projects that
81 * build a DLL. It can't easily be removed from those projects (it
82 * isn't visible in the Visual Studio UI) so it is a fairly reliable
83 * indication that PNG_IMPEXP needs to be set to the DLL export
86 # define PNG_BUILD_DLL
89 /* This is set by the Borland C system when compiling for a DLL
92 # define PNG_BUILD_DLL
94 /* Add additional compiler cases here. */
98 #endif /* Setting PNG_BUILD_DLL if required */
100 /* See pngconf.h for more details: the builder of the library may set this on
101 * the command line to the right thing for the specific compilation system or it
102 * may be automagically set above (at present we know of no system where it does
103 * need to be set on the command line.)
105 * PNG_IMPEXP must be set here when building the library to prevent pngconf.h
106 * setting it to the "import" setting for a DLL build.
109 # ifdef PNG_BUILD_DLL
110 # define PNG_IMPEXP PNG_DLL_EXPORT
112 /* Not building a DLL, or the DLL doesn't require specific export
119 /* No warnings for private or deprecated functions in the build: */
120 #ifndef PNG_DEPRECATED
121 # define PNG_DEPRECATED
129 #include "pngstruct.h"
131 /* pngconf.h does not set PNG_DLL_EXPORT unless it is required, so: */
132 #ifndef PNG_DLL_EXPORT
133 # define PNG_DLL_EXPORT
136 /* This is used for 16 bit gamma tables - only the top level pointers are const,
137 * this could be changed:
139 typedef PNG_CONST png_uint_16p FAR * png_const_uint_16pp;
141 /* Added at libpng-1.2.9 */
142 /* Moved to pngpriv.h at libpng-1.5.0 */
144 /* config.h is created by and PNG_CONFIGURE_LIBPNG is set by the "configure"
145 * script. We may need it here to get the correct configuration on things
148 #ifdef PNG_CONFIGURE_LIBPNG
149 # ifdef HAVE_CONFIG_H
154 /* Moved to pngpriv.h at libpng-1.5.0 */
155 /* NOTE: some of these may have been used in external applications as
156 * these definitions were exposed in pngconf.h prior to 1.5.
159 /* If you are running on a machine where you cannot allocate more
160 * than 64K of memory at once, uncomment this. While libpng will not
161 * normally need that much memory in a chunk (unless you load up a very
162 * large file), zlib needs to know how big of a chunk it can use, and
163 * libpng thus makes sure to check any memory allocation to verify it
164 * will fit into memory.
166 * zlib provides 'MAXSEG_64K' which, if defined, indicates the
167 * same limit and pngconf.h (already included) sets the limit
168 * if certain operating systems are detected.
170 #if defined(MAXSEG_64K) && !defined(PNG_MAX_MALLOC_64K)
171 # define PNG_MAX_MALLOC_64K
175 /* Unused formal parameter warnings are silenced using the following macro
176 * which is expected to have no bad effects on performance (optimizing
177 * compilers will probably remove it entirely). Note that if you replace
178 * it with something other than whitespace, you must include the terminating
181 # define PNG_UNUSED(param) (void)param;
184 /* Just a little check that someone hasn't tried to define something
187 #if (PNG_ZBUF_SIZE > 65536L) && defined(PNG_MAX_MALLOC_64K)
188 # undef PNG_ZBUF_SIZE
189 # define PNG_ZBUF_SIZE 65536L
192 /* PNG_STATIC is used to mark internal file scope functions if they need to be
193 * accessed for implementation tests (see the code in tests/?*).
196 # define PNG_STATIC static
199 /* C99 restrict is used where possible, to do this 'restrict' is defined as
200 * empty if we can't be sure it is supported. configure builds have already
203 #ifdef PNG_CONFIGURE_LIBPNG
204 # define PNG_RESTRICT restrict
206 /* Modern compilers support restrict, but assume not for anything not
209 # if defined __GNUC__ || defined _MSC_VER || defined __WATCOMC__
210 # define PNG_RESTRICT restrict
212 # define PNG_RESTRICT
216 /* If warnings or errors are turned off the code is disabled or redirected here.
217 * From 1.5.4 functions have been added to allow very limited formatting of
218 * error and warning messages - this code will also be disabled here.
220 #ifdef PNG_WARNINGS_SUPPORTED
221 # define PNG_WARNING_PARAMETERS(p) png_warning_parameters p;
223 # define png_warning(s1,s2) ((void)(s1))
224 # define png_chunk_warning(s1,s2) ((void)(s1))
225 # define png_warning_parameter(p,number,string) ((void)0)
226 # define png_warning_parameter_unsigned(p,number,format,value) ((void)0)
227 # define png_warning_parameter_signed(p,number,format,value) ((void)0)
228 # define png_formatted_warning(pp,p,message) ((void)(pp))
229 # define PNG_WARNING_PARAMETERS(p)
231 #ifndef PNG_ERROR_TEXT_SUPPORTED
232 # define png_error(s1,s2) png_err(s1)
233 # define png_chunk_error(s1,s2) png_err(s1)
234 # define png_fixed_error(s1,s2) png_err(s1)
237 /* C allows up-casts from (void*) to any pointer and (const void*) to any
238 * pointer to a const object. C++ regards this as a type error and requires an
239 * explicit, static, cast and provides the static_cast<> rune to ensure that
240 * const is not cast away.
243 # define png_voidcast(type, value) static_cast<type>(value)
245 # define png_voidcast(type, value) (value)
246 #endif /* __cplusplus */
249 /* The functions exported by PNG_EXTERN are internal functions, which
250 * aren't usually used outside the library (as far as I know), so it is
251 * debatable if they should be exported at all. In the future, when it
252 * is possible to have run-time registry of chunk-handling functions,
253 * some of these might be made available again.
255 * 1.5.7: turned the use of 'extern' back on, since it is localized to pngpriv.h
256 * it should be safe now (it is unclear why it was turned off.)
258 # define PNG_EXTERN extern
261 /* Some fixed point APIs are still required even if not exported because
262 * they get used by the corresponding floating point APIs. This magic
265 #ifdef PNG_FIXED_POINT_SUPPORTED
266 # define PNGFAPI PNGAPI
268 # define PNGFAPI /* PRIVATE */
271 /* Other defines specific to compilers can go here. Try to keep
272 * them inside an appropriate ifdef/endif pair for portability.
274 #if defined(PNG_FLOATING_POINT_SUPPORTED) ||\
275 defined(PNG_FLOATING_ARITHMETIC_SUPPORTED)
276 /* png.c requires the following ANSI-C constants if the conversion of
277 * floating point to ASCII is implemented therein:
279 * DBL_DIG Maximum number of decimal digits (can be set to any constant)
280 * DBL_MIN Smallest normalized fp number (can be set to an arbitrary value)
281 * DBL_MAX Maximum floating point number (can be set to an arbitrary value)
285 # if (defined(__MWERKS__) && defined(macintosh)) || defined(applec) || \
286 defined(THINK_C) || defined(__SC__) || defined(TARGET_OS_MAC)
287 /* We need to check that <math.h> hasn't already been included earlier
288 * as it seems it doesn't agree with <fp.h>, yet we should really use
289 * <fp.h> if possible.
291 # if !defined(__MATH_H__) && !defined(__MATH_H) && !defined(__cmath__)
297 # if defined(_AMIGA) && defined(__SASC) && defined(_M68881)
298 /* Amiga SAS/C: We must include builtin FPU functions when compiling using
305 /* This provides the non-ANSI (far) memory allocation routines. */
306 #if defined(__TURBOC__) && defined(__MSDOS__)
311 #if defined(WIN32) || defined(_Windows) || defined(_WINDOWS) || \
312 defined(_WIN32) || defined(__WIN32__)
313 # include <windows.h> /* defines _WINDOWS_ macro */
316 /* Moved here around 1.5.0beta36 from pngconf.h */
317 /* Users may want to use these so they are not private. Any library
318 * functions that are passed far data must be model-independent.
321 /* Memory model/platform independent fns */
324 # define PNG_ABORT() ExitProcess(0)
326 # define PNG_ABORT() abort()
330 #ifdef USE_FAR_KEYWORD
331 /* Use this to make far-to-near assignments */
334 # define CVT_PTR(ptr) (png_far_to_near(png_ptr,ptr,CHECK))
335 # define CVT_PTR_NOCHECK(ptr) (png_far_to_near(png_ptr,ptr,NOCHECK))
336 # define png_strlen _fstrlen
337 # define png_memcmp _fmemcmp /* SJT: added */
338 # define png_memcpy _fmemcpy
339 # define png_memset _fmemset
341 # ifdef _WINDOWS_ /* Favor Windows over C runtime fns */
342 # define CVT_PTR(ptr) (ptr)
343 # define CVT_PTR_NOCHECK(ptr) (ptr)
344 # define png_strlen lstrlenA
345 # define png_memcmp memcmp
346 # define png_memcpy CopyMemory
347 # define png_memset memset
349 # define CVT_PTR(ptr) (ptr)
350 # define CVT_PTR_NOCHECK(ptr) (ptr)
351 # define png_strlen strlen
352 # define png_memcmp memcmp /* SJT: added */
353 # define png_memcpy memcpy
354 # define png_memset memset
358 /* These macros may need to be architecture dependent. */
359 #define PNG_ALIGN_NONE 0 /* do not use data alignment */
360 #define PNG_ALIGN_ALWAYS 1 /* assume unaligned accesses are OK */
362 # define PNG_ALIGN_OFFSET 2 /* use offsetof to determine alignment */
364 # define PNG_ALIGN_OFFSET -1 /* prevent the use of this */
366 #define PNG_ALIGN_SIZE 3 /* use sizeof to determine alignment */
368 #ifndef PNG_ALIGN_TYPE
369 /* Default to using aligned access optimizations and requiring alignment to a
370 * multiple of the data type size. Override in a compiler specific fashion
371 * if necessary by inserting tests here:
373 # define PNG_ALIGN_TYPE PNG_ALIGN_SIZE
376 #if PNG_ALIGN_TYPE == PNG_ALIGN_SIZE
377 /* This is used because in some compiler implementations non-aligned
378 * structure members are supported, so the offsetof approach below fails.
379 * Set PNG_ALIGN_TO_SIZE=0 for compiler combinations where unaligned access
380 * is good for performance. Do not do this unless you have tested the result
383 # define png_alignof(type) (sizeof (type))
385 # if PNG_ALIGN_TYPE == PNG_ALIGN_OFFSET
386 # define png_alignof(type) offsetof(struct{char c; type t;}, t)
388 # if PNG_ALIGN_TYPE == PNG_ALIGN_ALWAYS
389 # define png_alignof(type) (1)
391 /* Else leave png_alignof undefined to prevent use thereof */
395 /* This implicitly assumes alignment is always to a power of 2. */
397 # define png_isaligned(ptr, type)\
398 ((((const char*)ptr-(const char*)0) & (png_alignof(type)-1)) == 0)
400 # define png_isaligned(ptr, type) 0
403 /* End of memory model/platform independent support */
404 /* End of 1.5.0beta36 move from pngconf.h */
406 /* CONSTANTS and UTILITY MACROS
407 * These are used internally by libpng and not exposed in the API
410 /* Various modes of operation. Note that after an init, mode is set to
411 * zero automatically when the structure is created. Three of these
412 * are defined in png.h because they need to be visible to applications
413 * that call png_set_unknown_chunk().
415 /* #define PNG_HAVE_IHDR 0x01 (defined in png.h) */
416 /* #define PNG_HAVE_PLTE 0x02 (defined in png.h) */
417 #define PNG_HAVE_IDAT 0x04
418 /* #define PNG_AFTER_IDAT 0x08 (defined in png.h) */
419 #define PNG_HAVE_IEND 0x10
420 #define PNG_HAVE_gAMA 0x20
421 #define PNG_HAVE_cHRM 0x40
422 #define PNG_HAVE_sRGB 0x80
423 #define PNG_HAVE_CHUNK_HEADER 0x100
424 #define PNG_WROTE_tIME 0x200
425 #define PNG_WROTE_INFO_BEFORE_PLTE 0x400
426 #define PNG_BACKGROUND_IS_GRAY 0x800
427 #define PNG_HAVE_PNG_SIGNATURE 0x1000
428 #define PNG_HAVE_CHUNK_AFTER_IDAT 0x2000 /* Have another chunk after IDAT */
430 /* Flags for the transformations the PNG library does on the image data */
431 #define PNG_BGR 0x0001
432 #define PNG_INTERLACE 0x0002
433 #define PNG_PACK 0x0004
434 #define PNG_SHIFT 0x0008
435 #define PNG_SWAP_BYTES 0x0010
436 #define PNG_INVERT_MONO 0x0020
437 #define PNG_QUANTIZE 0x0040
438 #define PNG_COMPOSE 0x0080 /* Was PNG_BACKGROUND */
439 #define PNG_BACKGROUND_EXPAND 0x0100
440 #define PNG_EXPAND_16 0x0200 /* Added to libpng 1.5.2 */
441 #define PNG_16_TO_8 0x0400 /* Becomes 'chop' in 1.5.4 */
442 #define PNG_RGBA 0x0800
443 #define PNG_EXPAND 0x1000
444 #define PNG_GAMMA 0x2000
445 #define PNG_GRAY_TO_RGB 0x4000
446 #define PNG_FILLER 0x8000
447 #define PNG_PACKSWAP 0x10000
448 #define PNG_SWAP_ALPHA 0x20000
449 #define PNG_STRIP_ALPHA 0x40000
450 #define PNG_INVERT_ALPHA 0x80000
451 #define PNG_USER_TRANSFORM 0x100000
452 #define PNG_RGB_TO_GRAY_ERR 0x200000
453 #define PNG_RGB_TO_GRAY_WARN 0x400000
454 #define PNG_RGB_TO_GRAY 0x600000 /* two bits, RGB_TO_GRAY_ERR|WARN */
455 #define PNG_ENCODE_ALPHA 0x800000 /* Added to libpng-1.5.4 */
456 #define PNG_ADD_ALPHA 0x1000000 /* Added to libpng-1.2.7 */
457 #define PNG_EXPAND_tRNS 0x2000000 /* Added to libpng-1.2.9 */
458 #define PNG_SCALE_16_TO_8 0x4000000 /* Added to libpng-1.5.4 */
459 /* 0x8000000 unused */
460 /* 0x10000000 unused */
461 /* 0x20000000 unused */
462 /* 0x40000000 unused */
463 /* Flags for png_create_struct */
464 #define PNG_STRUCT_PNG 0x0001
465 #define PNG_STRUCT_INFO 0x0002
467 /* Scaling factor for filter heuristic weighting calculations */
468 #define PNG_WEIGHT_FACTOR (1<<(PNG_WEIGHT_SHIFT))
469 #define PNG_COST_FACTOR (1<<(PNG_COST_SHIFT))
471 /* Flags for the png_ptr->flags rather than declaring a byte for each one */
472 #define PNG_FLAG_ZLIB_CUSTOM_STRATEGY 0x0001
473 #define PNG_FLAG_ZLIB_CUSTOM_LEVEL 0x0002
474 #define PNG_FLAG_ZLIB_CUSTOM_MEM_LEVEL 0x0004
475 #define PNG_FLAG_ZLIB_CUSTOM_WINDOW_BITS 0x0008
476 #define PNG_FLAG_ZLIB_CUSTOM_METHOD 0x0010
477 #define PNG_FLAG_ZLIB_FINISHED 0x0020
478 #define PNG_FLAG_ROW_INIT 0x0040
479 #define PNG_FLAG_FILLER_AFTER 0x0080
480 #define PNG_FLAG_CRC_ANCILLARY_USE 0x0100
481 #define PNG_FLAG_CRC_ANCILLARY_NOWARN 0x0200
482 #define PNG_FLAG_CRC_CRITICAL_USE 0x0400
483 #define PNG_FLAG_CRC_CRITICAL_IGNORE 0x0800
484 #define PNG_FLAG_ASSUME_sRGB 0x1000 /* Added to libpng-1.5.4 */
485 #define PNG_FLAG_OPTIMIZE_ALPHA 0x2000 /* Added to libpng-1.5.4 */
486 #define PNG_FLAG_DETECT_UNINITIALIZED 0x4000 /* Added to libpng-1.5.4 */
487 #define PNG_FLAG_KEEP_UNKNOWN_CHUNKS 0x8000
488 #define PNG_FLAG_KEEP_UNSAFE_CHUNKS 0x10000
489 #define PNG_FLAG_LIBRARY_MISMATCH 0x20000
490 #define PNG_FLAG_STRIP_ERROR_NUMBERS 0x40000
491 #define PNG_FLAG_STRIP_ERROR_TEXT 0x80000
492 #define PNG_FLAG_MALLOC_NULL_MEM_OK 0x100000
493 /* 0x200000 unused */
494 /* 0x400000 unused */
495 #define PNG_FLAG_BENIGN_ERRORS_WARN 0x800000 /* Added to libpng-1.4.0 */
496 #define PNG_FLAG_ZTXT_CUSTOM_STRATEGY 0x1000000 /* 5 lines added */
497 #define PNG_FLAG_ZTXT_CUSTOM_LEVEL 0x2000000 /* to libpng-1.5.4 */
498 #define PNG_FLAG_ZTXT_CUSTOM_MEM_LEVEL 0x4000000
499 #define PNG_FLAG_ZTXT_CUSTOM_WINDOW_BITS 0x8000000
500 #define PNG_FLAG_ZTXT_CUSTOM_METHOD 0x10000000
501 /* 0x20000000 unused */
502 /* 0x40000000 unused */
504 #define PNG_FLAG_CRC_ANCILLARY_MASK (PNG_FLAG_CRC_ANCILLARY_USE | \
505 PNG_FLAG_CRC_ANCILLARY_NOWARN)
507 #define PNG_FLAG_CRC_CRITICAL_MASK (PNG_FLAG_CRC_CRITICAL_USE | \
508 PNG_FLAG_CRC_CRITICAL_IGNORE)
510 #define PNG_FLAG_CRC_MASK (PNG_FLAG_CRC_ANCILLARY_MASK | \
511 PNG_FLAG_CRC_CRITICAL_MASK)
513 /* zlib.h declares a magic type 'uInt' that limits the amount of data that zlib
514 * can handle at once. This type need be no larger than 16 bits (so maximum of
515 * 65535), this define allows us to discover how big it is, but limited by the
516 * maximuum for png_size_t. The value can be overriden in a library build
517 * (pngusr.h, or set it in CPPFLAGS) and it works to set it to a considerably
518 * lower value (e.g. 255 works). A lower value may help memory usage (slightly)
519 * and may even improve performance on some systems (and degrade it on others.)
522 # define ZLIB_IO_MAX ((uInt)-1)
525 /* Save typing and make code easier to understand */
527 #define PNG_COLOR_DIST(c1, c2) (abs((int)((c1).red) - (int)((c2).red)) + \
528 abs((int)((c1).green) - (int)((c2).green)) + \
529 abs((int)((c1).blue) - (int)((c2).blue)))
531 /* Added to libpng-1.2.6 JB */
532 #define PNG_ROWBYTES(pixel_bits, width) \
533 ((pixel_bits) >= 8 ? \
534 ((png_size_t)(width) * (((png_size_t)(pixel_bits)) >> 3)) : \
535 (( ((png_size_t)(width) * ((png_size_t)(pixel_bits))) + 7) >> 3) )
537 /* PNG_OUT_OF_RANGE returns true if value is outside the range
538 * ideal-delta..ideal+delta. Each argument is evaluated twice.
539 * "ideal" and "delta" should be constants, normally simple
540 * integers, "value" a variable. Added to libpng-1.2.6 JB
542 #define PNG_OUT_OF_RANGE(value, ideal, delta) \
543 ( (value) < (ideal)-(delta) || (value) > (ideal)+(delta) )
545 /* Conversions between fixed and floating point, only defined if
546 * required (to make sure the code doesn't accidentally use float
547 * when it is supposedly disabled.)
549 #ifdef PNG_FLOATING_POINT_SUPPORTED
550 /* The floating point conversion can't overflow, though it can and
551 * does lose accuracy relative to the original fixed point value.
552 * In practice this doesn't matter because png_fixed_point only
553 * stores numbers with very low precision. The png_ptr and s
554 * arguments are unused by default but are there in case error
555 * checking becomes a requirement.
557 #define png_float(png_ptr, fixed, s) (.00001 * (fixed))
559 /* The fixed point conversion performs range checking and evaluates
560 * its argument multiple times, so must be used with care. The
561 * range checking uses the PNG specification values for a signed
562 * 32 bit fixed point value except that the values are deliberately
563 * rounded-to-zero to an integral value - 21474 (21474.83 is roughly
564 * (2^31-1) * 100000). 's' is a string that describes the value being
567 * NOTE: this macro will raise a png_error if the range check fails,
568 * therefore it is normally only appropriate to use this on values
569 * that come from API calls or other sources where an out of range
570 * error indicates a programming error, not a data error!
572 * NOTE: by default this is off - the macro is not used - because the
573 * function call saves a lot of code.
575 #ifdef PNG_FIXED_POINT_MACRO_SUPPORTED
576 #define png_fixed(png_ptr, fp, s) ((fp) <= 21474 && (fp) >= -21474 ?\
577 ((png_fixed_point)(100000 * (fp))) : (png_fixed_error(png_ptr, s),0))
579 PNG_EXTERN png_fixed_point png_fixed PNGARG((png_structp png_ptr, double fp,
580 png_const_charp text));
584 /* Constants for known chunk types. If you need to add a chunk, define the name
585 * here. For historical reasons these constants have the form png_<name>; i.e.
586 * the prefix is lower case. Please use decimal values as the parameters to
587 * match the ISO PNG specification and to avoid relying on the C locale
588 * interpretation of character values.
590 * Prior to 1.5.6 these constants were strings, as of 1.5.6 png_uint_32 values
591 * are computed and a new macro (PNG_STRING_FROM_CHUNK) added to allow a string
592 * to be generated if required.
594 * PNG_32b correctly produces a value shifted by up to 24 bits, even on
595 * architectures where (int) is only 16 bits.
597 #define PNG_32b(b,s) ((png_uint_32)(b) << (s))
598 #define PNG_CHUNK(b1,b2,b3,b4) \
599 (PNG_32b(b1,24) | PNG_32b(b2,16) | PNG_32b(b3,8) | PNG_32b(b4,0))
601 #define png_IHDR PNG_CHUNK( 73, 72, 68, 82)
602 #define png_IDAT PNG_CHUNK( 73, 68, 65, 84)
603 #define png_IEND PNG_CHUNK( 73, 69, 78, 68)
604 #define png_PLTE PNG_CHUNK( 80, 76, 84, 69)
605 #define png_bKGD PNG_CHUNK( 98, 75, 71, 68)
606 #define png_cHRM PNG_CHUNK( 99, 72, 82, 77)
607 #define png_gAMA PNG_CHUNK(103, 65, 77, 65)
608 #define png_hIST PNG_CHUNK(104, 73, 83, 84)
609 #define png_iCCP PNG_CHUNK(105, 67, 67, 80)
610 #define png_iTXt PNG_CHUNK(105, 84, 88, 116)
611 #define png_oFFs PNG_CHUNK(111, 70, 70, 115)
612 #define png_pCAL PNG_CHUNK(112, 67, 65, 76)
613 #define png_sCAL PNG_CHUNK(115, 67, 65, 76)
614 #define png_pHYs PNG_CHUNK(112, 72, 89, 115)
615 #define png_sBIT PNG_CHUNK(115, 66, 73, 84)
616 #define png_sPLT PNG_CHUNK(115, 80, 76, 84)
617 #define png_sRGB PNG_CHUNK(115, 82, 71, 66)
618 #define png_sTER PNG_CHUNK(115, 84, 69, 82)
619 #define png_tEXt PNG_CHUNK(116, 69, 88, 116)
620 #define png_tIME PNG_CHUNK(116, 73, 77, 69)
621 #define png_tRNS PNG_CHUNK(116, 82, 78, 83)
622 #define png_zTXt PNG_CHUNK(122, 84, 88, 116)
624 /* The following will work on (signed char*) strings, whereas the get_uint_32
625 * macro will fail on top-bit-set values because of the sign extension.
627 #define PNG_CHUNK_FROM_STRING(s)\
628 PNG_CHUNK(0xff&(s)[0], 0xff&(s)[1], 0xff&(s)[2], 0xff&(s)[3])
630 /* This uses (char), not (png_byte) to avoid warnings on systems where (char) is
631 * signed and the argument is a (char[]) This macro will fail miserably on
632 * systems where (char) is more than 8 bits.
634 #define PNG_STRING_FROM_CHUNK(s,c)\
635 (void)(((char*)(s))[0]=(char)((c)>>24), ((char*)(s))[1]=(char)((c)>>16),\
636 ((char*)(s))[2]=(char)((c)>>8), ((char*)(s))[3]=(char)((c)))
638 /* Do the same but terminate with a null character. */
639 #define PNG_CSTRING_FROM_CHUNK(s,c)\
640 (void)(PNG_STRING_FROM_CHUNK(s,c), ((char*)(s))[4] = 0)
642 /* Test on flag values as defined in the spec (section 5.4): */
643 #define PNG_CHUNK_ANCILLIARY(c) (1 & ((c) >> 29))
644 #define PNG_CHUNK_CRITICAL(c) (!PNG_CHUNK_ANCILLIARY(c))
645 #define PNG_CHUNK_PRIVATE(c) (1 & ((c) >> 21))
646 #define PNG_CHUNK_RESERVED(c) (1 & ((c) >> 13))
647 #define PNG_CHUNK_SAFE_TO_COPY(c) (1 & ((c) >> 5))
649 /* Gamma values (new at libpng-1.5.4): */
650 #define PNG_GAMMA_MAC_OLD 151724 /* Assume '1.8' is really 2.2/1.45! */
651 #define PNG_GAMMA_MAC_INVERSE 65909
652 #define PNG_GAMMA_sRGB_INVERSE 45455
655 /* Inhibit C++ name-mangling for libpng functions but not for system calls. */
658 #endif /* __cplusplus */
660 /* These functions are used internally in the code. They generally
661 * shouldn't be used unless you are writing code to add or replace some
662 * functionality in libpng. More information about most functions can
663 * be found in the files where the functions are located.
666 /* Check the user version string for compatibility, returns false if the version
667 * numbers aren't compatible.
669 PNG_EXTERN int png_user_version_check(png_structp png_ptr,
670 png_const_charp user_png_ver);
672 /* Allocate memory for an internal libpng struct */
673 PNG_EXTERN PNG_FUNCTION(png_voidp,png_create_struct,PNGARG((int type)),
676 /* Free memory from internal libpng struct */
677 PNG_EXTERN void png_destroy_struct PNGARG((png_voidp struct_ptr));
679 PNG_EXTERN PNG_FUNCTION(png_voidp,png_create_struct_2,
680 PNGARG((int type, png_malloc_ptr malloc_fn, png_voidp mem_ptr)),
682 PNG_EXTERN void png_destroy_struct_2 PNGARG((png_voidp struct_ptr,
683 png_free_ptr free_fn, png_voidp mem_ptr));
685 /* Free any memory that info_ptr points to and reset struct. */
686 PNG_EXTERN void png_info_destroy PNGARG((png_structp png_ptr,
687 png_infop info_ptr));
689 /* Function to allocate memory for zlib. PNGAPI is disallowed. */
690 PNG_EXTERN PNG_FUNCTION(voidpf,png_zalloc,PNGARG((voidpf png_ptr, uInt items,
691 uInt size)),PNG_ALLOCATED);
693 /* Function to free memory for zlib. PNGAPI is disallowed. */
694 PNG_EXTERN void png_zfree PNGARG((voidpf png_ptr, voidpf ptr));
696 /* Next four functions are used internally as callbacks. PNGCBAPI is required
697 * but not PNG_EXPORT. PNGAPI added at libpng version 1.2.3, changed to
701 PNG_EXTERN void PNGCBAPI png_default_read_data PNGARG((png_structp png_ptr,
702 png_bytep data, png_size_t length));
704 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED
705 PNG_EXTERN void PNGCBAPI png_push_fill_buffer PNGARG((png_structp png_ptr,
706 png_bytep buffer, png_size_t length));
709 PNG_EXTERN void PNGCBAPI png_default_write_data PNGARG((png_structp png_ptr,
710 png_bytep data, png_size_t length));
712 #ifdef PNG_WRITE_FLUSH_SUPPORTED
713 # ifdef PNG_STDIO_SUPPORTED
714 PNG_EXTERN void PNGCBAPI png_default_flush PNGARG((png_structp png_ptr));
718 /* Reset the CRC variable */
719 PNG_EXTERN void png_reset_crc PNGARG((png_structp png_ptr));
721 /* Write the "data" buffer to whatever output you are using */
722 PNG_EXTERN void png_write_data PNGARG((png_structp png_ptr,
723 png_const_bytep data, png_size_t length));
725 /* Read and check the PNG file signature */
726 PNG_EXTERN void png_read_sig PNGARG((png_structp png_ptr, png_infop info_ptr));
728 /* Read the chunk header (length + type name) */
729 PNG_EXTERN png_uint_32 png_read_chunk_header PNGARG((png_structp png_ptr));
731 /* Read data from whatever input you are using into the "data" buffer */
732 PNG_EXTERN void png_read_data PNGARG((png_structp png_ptr, png_bytep data,
735 /* Read bytes into buf, and update png_ptr->crc */
736 PNG_EXTERN void png_crc_read PNGARG((png_structp png_ptr, png_bytep buf,
739 /* Decompress data in a chunk that uses compression */
740 #if defined(PNG_READ_COMPRESSED_TEXT_SUPPORTED)
741 PNG_EXTERN void png_decompress_chunk PNGARG((png_structp png_ptr,
742 int comp_type, png_size_t chunklength, png_size_t prefix_length,
743 png_size_t *data_length));
746 /* Read "skip" bytes, read the file crc, and (optionally) verify png_ptr->crc */
747 PNG_EXTERN int png_crc_finish PNGARG((png_structp png_ptr, png_uint_32 skip));
749 /* Read the CRC from the file and compare it to the libpng calculated CRC */
750 PNG_EXTERN int png_crc_error PNGARG((png_structp png_ptr));
752 /* Calculate the CRC over a section of data. Note that we are only
753 * passing a maximum of 64K on systems that have this as a memory limit,
754 * since this is the maximum buffer size we can specify.
756 PNG_EXTERN void png_calculate_crc PNGARG((png_structp png_ptr,
757 png_const_bytep ptr, png_size_t length));
759 #ifdef PNG_WRITE_FLUSH_SUPPORTED
760 PNG_EXTERN void png_flush PNGARG((png_structp png_ptr));
763 /* Write various chunks */
765 /* Write the IHDR chunk, and update the png_struct with the necessary
768 PNG_EXTERN void png_write_IHDR PNGARG((png_structp png_ptr, png_uint_32 width,
770 int bit_depth, int color_type, int compression_method, int filter_method,
771 int interlace_method));
773 PNG_EXTERN void png_write_PLTE PNGARG((png_structp png_ptr,
774 png_const_colorp palette, png_uint_32 num_pal));
776 PNG_EXTERN void png_write_IDAT PNGARG((png_structp png_ptr, png_bytep data,
779 PNG_EXTERN void png_write_IEND PNGARG((png_structp png_ptr));
781 #ifdef PNG_WRITE_gAMA_SUPPORTED
782 # ifdef PNG_FLOATING_POINT_SUPPORTED
783 PNG_EXTERN void png_write_gAMA PNGARG((png_structp png_ptr, double file_gamma));
785 # ifdef PNG_FIXED_POINT_SUPPORTED
786 PNG_EXTERN void png_write_gAMA_fixed PNGARG((png_structp png_ptr,
787 png_fixed_point file_gamma));
791 #ifdef PNG_WRITE_sBIT_SUPPORTED
792 PNG_EXTERN void png_write_sBIT PNGARG((png_structp png_ptr,
793 png_const_color_8p sbit, int color_type));
796 #ifdef PNG_WRITE_cHRM_SUPPORTED
797 # ifdef PNG_FLOATING_POINT_SUPPORTED
798 PNG_EXTERN void png_write_cHRM PNGARG((png_structp png_ptr,
799 double white_x, double white_y,
800 double red_x, double red_y, double green_x, double green_y,
801 double blue_x, double blue_y));
803 PNG_EXTERN void png_write_cHRM_fixed PNGARG((png_structp png_ptr,
804 png_fixed_point int_white_x, png_fixed_point int_white_y,
805 png_fixed_point int_red_x, png_fixed_point int_red_y, png_fixed_point
806 int_green_x, png_fixed_point int_green_y, png_fixed_point int_blue_x,
807 png_fixed_point int_blue_y));
810 #ifdef PNG_WRITE_sRGB_SUPPORTED
811 PNG_EXTERN void png_write_sRGB PNGARG((png_structp png_ptr,
815 #ifdef PNG_WRITE_iCCP_SUPPORTED
816 PNG_EXTERN void png_write_iCCP PNGARG((png_structp png_ptr,
817 png_const_charp name, int compression_type,
818 png_const_charp profile, int proflen));
819 /* Note to maintainer: profile should be png_bytep */
822 #ifdef PNG_WRITE_sPLT_SUPPORTED
823 PNG_EXTERN void png_write_sPLT PNGARG((png_structp png_ptr,
824 png_const_sPLT_tp palette));
827 #ifdef PNG_WRITE_tRNS_SUPPORTED
828 PNG_EXTERN void png_write_tRNS PNGARG((png_structp png_ptr,
829 png_const_bytep trans, png_const_color_16p values, int number,
833 #ifdef PNG_WRITE_bKGD_SUPPORTED
834 PNG_EXTERN void png_write_bKGD PNGARG((png_structp png_ptr,
835 png_const_color_16p values, int color_type));
838 #ifdef PNG_WRITE_hIST_SUPPORTED
839 PNG_EXTERN void png_write_hIST PNGARG((png_structp png_ptr,
840 png_const_uint_16p hist, int num_hist));
843 /* Chunks that have keywords */
844 #if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_pCAL_SUPPORTED) || \
845 defined(PNG_WRITE_iCCP_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED)
846 PNG_EXTERN png_size_t png_check_keyword PNGARG((png_structp png_ptr,
847 png_const_charp key, png_charpp new_key));
850 #ifdef PNG_WRITE_tEXt_SUPPORTED
851 PNG_EXTERN void png_write_tEXt PNGARG((png_structp png_ptr, png_const_charp key,
852 png_const_charp text, png_size_t text_len));
855 #ifdef PNG_WRITE_zTXt_SUPPORTED
856 PNG_EXTERN void png_write_zTXt PNGARG((png_structp png_ptr, png_const_charp key,
857 png_const_charp text, png_size_t text_len, int compression));
860 #ifdef PNG_WRITE_iTXt_SUPPORTED
861 PNG_EXTERN void png_write_iTXt PNGARG((png_structp png_ptr,
862 int compression, png_const_charp key, png_const_charp lang,
863 png_const_charp lang_key, png_const_charp text));
866 #ifdef PNG_TEXT_SUPPORTED /* Added at version 1.0.14 and 1.2.4 */
867 PNG_EXTERN int png_set_text_2 PNGARG((png_structp png_ptr,
868 png_infop info_ptr, png_const_textp text_ptr, int num_text));
871 #ifdef PNG_WRITE_oFFs_SUPPORTED
872 PNG_EXTERN void png_write_oFFs PNGARG((png_structp png_ptr,
873 png_int_32 x_offset, png_int_32 y_offset, int unit_type));
876 #ifdef PNG_WRITE_pCAL_SUPPORTED
877 PNG_EXTERN void png_write_pCAL PNGARG((png_structp png_ptr, png_charp purpose,
878 png_int_32 X0, png_int_32 X1, int type, int nparams,
879 png_const_charp units, png_charpp params));
882 #ifdef PNG_WRITE_pHYs_SUPPORTED
883 PNG_EXTERN void png_write_pHYs PNGARG((png_structp png_ptr,
884 png_uint_32 x_pixels_per_unit, png_uint_32 y_pixels_per_unit,
888 #ifdef PNG_WRITE_tIME_SUPPORTED
889 PNG_EXTERN void png_write_tIME PNGARG((png_structp png_ptr,
890 png_const_timep mod_time));
893 #ifdef PNG_WRITE_sCAL_SUPPORTED
894 PNG_EXTERN void png_write_sCAL_s PNGARG((png_structp png_ptr,
895 int unit, png_const_charp width, png_const_charp height));
898 /* Called when finished processing a row of data */
899 PNG_EXTERN void png_write_finish_row PNGARG((png_structp png_ptr));
901 /* Internal use only. Called before first row of data */
902 PNG_EXTERN void png_write_start_row PNGARG((png_structp png_ptr));
904 /* Combine a row of data, dealing with alpha, etc. if requested. 'row' is an
905 * array of png_ptr->width pixels. If the image is not interlaced or this
906 * is the final pass this just does a png_memcpy, otherwise the "display" flag
907 * is used to determine whether to copy pixels that are not in the current pass.
909 * Because 'png_do_read_interlace' (below) replicates pixels this allows this
910 * function to achieve the documented 'blocky' appearance during interlaced read
911 * if display is 1 and the 'sparkle' appearance, where existing pixels in 'row'
912 * are not changed if they are not in the current pass, when display is 0.
914 * 'display' must be 0 or 1, otherwise the memcpy will be done regardless.
916 * The API always reads from the png_struct row buffer and always assumes that
917 * it is full width (png_do_read_interlace has already been called.)
919 * This function is only ever used to write to row buffers provided by the
920 * caller of the relevant libpng API and the row must have already been
921 * transformed by the read transformations.
923 * The PNG_USE_COMPILE_TIME_MASKS option causes generation of pre-computed
924 * bitmasks for use within the code, otherwise runtime generated masks are used.
925 * The default is compile time masks.
927 #ifndef PNG_USE_COMPILE_TIME_MASKS
928 # define PNG_USE_COMPILE_TIME_MASKS 1
930 PNG_EXTERN void png_combine_row PNGARG((png_structp png_ptr, png_bytep row,
933 #ifdef PNG_READ_INTERLACING_SUPPORTED
934 /* Expand an interlaced row: the 'row_info' describes the pass data that has
935 * been read in and must correspond to the pixels in 'row', the pixels are
936 * expanded (moved apart) in 'row' to match the final layout, when doing this
937 * the pixels are *replicated* to the intervening space. This is essential for
938 * the correct operation of png_combine_row, above.
940 PNG_EXTERN void png_do_read_interlace PNGARG((png_row_infop row_info,
941 png_bytep row, int pass, png_uint_32 transformations));
944 /* GRR TO DO (2.0 or whenever): simplify other internal calling interfaces */
946 #ifdef PNG_WRITE_INTERLACING_SUPPORTED
947 /* Grab pixels out of a row for an interlaced pass */
948 PNG_EXTERN void png_do_write_interlace PNGARG((png_row_infop row_info,
949 png_bytep row, int pass));
952 /* Unfilter a row: check the filter value before calling this, there is no point
953 * calling it for PNG_FILTER_VALUE_NONE.
955 PNG_EXTERN void png_read_filter_row PNGARG((png_structp pp, png_row_infop row_info,
956 png_bytep row, png_const_bytep prev_row, int filter));
958 PNG_EXTERN void png_read_filter_row_up_neon PNGARG((png_row_infop row_info,
959 png_bytep row, png_const_bytep prev_row));
960 PNG_EXTERN void png_read_filter_row_sub3_neon PNGARG((png_row_infop row_info,
961 png_bytep row, png_const_bytep prev_row));
962 PNG_EXTERN void png_read_filter_row_sub4_neon PNGARG((png_row_infop row_info,
963 png_bytep row, png_const_bytep prev_row));
964 PNG_EXTERN void png_read_filter_row_avg3_neon PNGARG((png_row_infop row_info,
965 png_bytep row, png_const_bytep prev_row));
966 PNG_EXTERN void png_read_filter_row_avg4_neon PNGARG((png_row_infop row_info,
967 png_bytep row, png_const_bytep prev_row));
968 PNG_EXTERN void png_read_filter_row_paeth3_neon PNGARG((png_row_infop row_info,
969 png_bytep row, png_const_bytep prev_row));
970 PNG_EXTERN void png_read_filter_row_paeth4_neon PNGARG((png_row_infop row_info,
971 png_bytep row, png_const_bytep prev_row));
973 /* Choose the best filter to use and filter the row data */
974 PNG_EXTERN void png_write_find_filter PNGARG((png_structp png_ptr,
975 png_row_infop row_info));
977 /* Finish a row while reading, dealing with interlacing passes, etc. */
978 PNG_EXTERN void png_read_finish_row PNGARG((png_structp png_ptr));
980 /* Initialize the row buffers, etc. */
981 PNG_EXTERN void png_read_start_row PNGARG((png_structp png_ptr));
983 #ifdef PNG_READ_TRANSFORMS_SUPPORTED
984 /* Optional call to update the users info structure */
985 PNG_EXTERN void png_read_transform_info PNGARG((png_structp png_ptr,
986 png_infop info_ptr));
989 /* These are the functions that do the transformations */
990 #ifdef PNG_READ_FILLER_SUPPORTED
991 PNG_EXTERN void png_do_read_filler PNGARG((png_row_infop row_info,
992 png_bytep row, png_uint_32 filler, png_uint_32 flags));
995 #ifdef PNG_READ_SWAP_ALPHA_SUPPORTED
996 PNG_EXTERN void png_do_read_swap_alpha PNGARG((png_row_infop row_info,
1000 #ifdef PNG_WRITE_SWAP_ALPHA_SUPPORTED
1001 PNG_EXTERN void png_do_write_swap_alpha PNGARG((png_row_infop row_info,
1005 #ifdef PNG_READ_INVERT_ALPHA_SUPPORTED
1006 PNG_EXTERN void png_do_read_invert_alpha PNGARG((png_row_infop row_info,
1010 #ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED
1011 PNG_EXTERN void png_do_write_invert_alpha PNGARG((png_row_infop row_info,
1015 #if defined(PNG_WRITE_FILLER_SUPPORTED) || \
1016 defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
1017 PNG_EXTERN void png_do_strip_channel PNGARG((png_row_infop row_info,
1018 png_bytep row, int at_start));
1021 #ifdef PNG_16BIT_SUPPORTED
1022 #if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
1023 PNG_EXTERN void png_do_swap PNGARG((png_row_infop row_info,
1028 #if defined(PNG_READ_PACKSWAP_SUPPORTED) || \
1029 defined(PNG_WRITE_PACKSWAP_SUPPORTED)
1030 PNG_EXTERN void png_do_packswap PNGARG((png_row_infop row_info,
1034 #ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
1035 PNG_EXTERN int png_do_rgb_to_gray PNGARG((png_structp png_ptr,
1036 png_row_infop row_info, png_bytep row));
1039 #ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED
1040 PNG_EXTERN void png_do_gray_to_rgb PNGARG((png_row_infop row_info,
1044 #ifdef PNG_READ_PACK_SUPPORTED
1045 PNG_EXTERN void png_do_unpack PNGARG((png_row_infop row_info,
1049 #ifdef PNG_READ_SHIFT_SUPPORTED
1050 PNG_EXTERN void png_do_unshift PNGARG((png_row_infop row_info,
1051 png_bytep row, png_const_color_8p sig_bits));
1054 #if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
1055 PNG_EXTERN void png_do_invert PNGARG((png_row_infop row_info,
1059 #ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED
1060 PNG_EXTERN void png_do_scale_16_to_8 PNGARG((png_row_infop row_info,
1064 #ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED
1065 PNG_EXTERN void png_do_chop PNGARG((png_row_infop row_info,
1069 #ifdef PNG_READ_QUANTIZE_SUPPORTED
1070 PNG_EXTERN void png_do_quantize PNGARG((png_row_infop row_info,
1071 png_bytep row, png_const_bytep palette_lookup,
1072 png_const_bytep quantize_lookup));
1074 # ifdef PNG_CORRECT_PALETTE_SUPPORTED
1075 PNG_EXTERN void png_correct_palette PNGARG((png_structp png_ptr,
1076 png_colorp palette, int num_palette));
1080 #if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
1081 PNG_EXTERN void png_do_bgr PNGARG((png_row_infop row_info,
1085 #ifdef PNG_WRITE_PACK_SUPPORTED
1086 PNG_EXTERN void png_do_pack PNGARG((png_row_infop row_info,
1087 png_bytep row, png_uint_32 bit_depth));
1090 #ifdef PNG_WRITE_SHIFT_SUPPORTED
1091 PNG_EXTERN void png_do_shift PNGARG((png_row_infop row_info,
1092 png_bytep row, png_const_color_8p bit_depth));
1095 #if defined(PNG_READ_BACKGROUND_SUPPORTED) ||\
1096 defined(PNG_READ_ALPHA_MODE_SUPPORTED)
1097 PNG_EXTERN void png_do_compose PNGARG((png_row_infop row_info,
1098 png_bytep row, png_structp png_ptr));
1101 #ifdef PNG_READ_GAMMA_SUPPORTED
1102 PNG_EXTERN void png_do_gamma PNGARG((png_row_infop row_info,
1103 png_bytep row, png_structp png_ptr));
1106 #ifdef PNG_READ_ALPHA_MODE_SUPPORTED
1107 PNG_EXTERN void png_do_encode_alpha PNGARG((png_row_infop row_info,
1108 png_bytep row, png_structp png_ptr));
1111 #ifdef PNG_READ_EXPAND_SUPPORTED
1112 PNG_EXTERN void png_do_expand_palette PNGARG((png_row_infop row_info,
1113 png_bytep row, png_const_colorp palette, png_const_bytep trans,
1115 PNG_EXTERN void png_do_expand PNGARG((png_row_infop row_info,
1116 png_bytep row, png_const_color_16p trans_color));
1119 #ifdef PNG_READ_EXPAND_16_SUPPORTED
1120 PNG_EXTERN void png_do_expand_16 PNGARG((png_row_infop row_info,
1124 /* The following decodes the appropriate chunks, and does error correction,
1125 * then calls the appropriate callback for the chunk if it is valid.
1128 /* Decode the IHDR chunk */
1129 PNG_EXTERN void png_handle_IHDR PNGARG((png_structp png_ptr, png_infop info_ptr,
1130 png_uint_32 length));
1131 PNG_EXTERN void png_handle_PLTE PNGARG((png_structp png_ptr, png_infop info_ptr,
1132 png_uint_32 length));
1133 PNG_EXTERN void png_handle_IEND PNGARG((png_structp png_ptr, png_infop info_ptr,
1134 png_uint_32 length));
1136 #ifdef PNG_READ_bKGD_SUPPORTED
1137 PNG_EXTERN void png_handle_bKGD PNGARG((png_structp png_ptr, png_infop info_ptr,
1138 png_uint_32 length));
1141 #ifdef PNG_READ_cHRM_SUPPORTED
1142 PNG_EXTERN void png_handle_cHRM PNGARG((png_structp png_ptr, png_infop info_ptr,
1143 png_uint_32 length));
1146 #ifdef PNG_READ_gAMA_SUPPORTED
1147 PNG_EXTERN void png_handle_gAMA PNGARG((png_structp png_ptr, png_infop info_ptr,
1148 png_uint_32 length));
1151 #ifdef PNG_READ_hIST_SUPPORTED
1152 PNG_EXTERN void png_handle_hIST PNGARG((png_structp png_ptr, png_infop info_ptr,
1153 png_uint_32 length));
1156 #ifdef PNG_READ_iCCP_SUPPORTED
1157 PNG_EXTERN void png_handle_iCCP PNGARG((png_structp png_ptr, png_infop info_ptr,
1158 png_uint_32 length));
1159 #endif /* PNG_READ_iCCP_SUPPORTED */
1161 #ifdef PNG_READ_iTXt_SUPPORTED
1162 PNG_EXTERN void png_handle_iTXt PNGARG((png_structp png_ptr, png_infop info_ptr,
1163 png_uint_32 length));
1166 #ifdef PNG_READ_oFFs_SUPPORTED
1167 PNG_EXTERN void png_handle_oFFs PNGARG((png_structp png_ptr, png_infop info_ptr,
1168 png_uint_32 length));
1171 #ifdef PNG_READ_pCAL_SUPPORTED
1172 PNG_EXTERN void png_handle_pCAL PNGARG((png_structp png_ptr, png_infop info_ptr,
1173 png_uint_32 length));
1176 #ifdef PNG_READ_pHYs_SUPPORTED
1177 PNG_EXTERN void png_handle_pHYs PNGARG((png_structp png_ptr, png_infop info_ptr,
1178 png_uint_32 length));
1181 #ifdef PNG_READ_sBIT_SUPPORTED
1182 PNG_EXTERN void png_handle_sBIT PNGARG((png_structp png_ptr, png_infop info_ptr,
1183 png_uint_32 length));
1186 #ifdef PNG_READ_sCAL_SUPPORTED
1187 PNG_EXTERN void png_handle_sCAL PNGARG((png_structp png_ptr, png_infop info_ptr,
1188 png_uint_32 length));
1191 #ifdef PNG_READ_sPLT_SUPPORTED
1192 PNG_EXTERN void png_handle_sPLT PNGARG((png_structp png_ptr, png_infop info_ptr,
1193 png_uint_32 length));
1194 #endif /* PNG_READ_sPLT_SUPPORTED */
1196 #ifdef PNG_READ_sRGB_SUPPORTED
1197 PNG_EXTERN void png_handle_sRGB PNGARG((png_structp png_ptr, png_infop info_ptr,
1198 png_uint_32 length));
1201 #ifdef PNG_READ_tEXt_SUPPORTED
1202 PNG_EXTERN void png_handle_tEXt PNGARG((png_structp png_ptr, png_infop info_ptr,
1203 png_uint_32 length));
1206 #ifdef PNG_READ_tIME_SUPPORTED
1207 PNG_EXTERN void png_handle_tIME PNGARG((png_structp png_ptr, png_infop info_ptr,
1208 png_uint_32 length));
1211 #ifdef PNG_READ_tRNS_SUPPORTED
1212 PNG_EXTERN void png_handle_tRNS PNGARG((png_structp png_ptr, png_infop info_ptr,
1213 png_uint_32 length));
1216 #ifdef PNG_READ_zTXt_SUPPORTED
1217 PNG_EXTERN void png_handle_zTXt PNGARG((png_structp png_ptr, png_infop info_ptr,
1218 png_uint_32 length));
1221 #ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
1222 PNG_EXTERN void png_handle_unknown PNGARG((png_structp png_ptr,
1223 png_infop info_ptr, png_uint_32 length));
1226 PNG_EXTERN void png_check_chunk_name PNGARG((png_structp png_ptr,
1227 png_uint_32 chunk_name));
1229 #ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
1230 /* Exactly as png_handle_as_unknown() except that the argument is a 32-bit chunk
1231 * name, not a string.
1233 PNG_EXTERN int png_chunk_unknown_handling PNGARG((png_structp png_ptr,
1234 png_uint_32 chunk_name));
1237 /* Handle the transformations for reading and writing */
1238 #ifdef PNG_READ_TRANSFORMS_SUPPORTED
1239 PNG_EXTERN void png_do_read_transformations PNGARG((png_structp png_ptr,
1240 png_row_infop row_info));
1242 #ifdef PNG_WRITE_TRANSFORMS_SUPPORTED
1243 PNG_EXTERN void png_do_write_transformations PNGARG((png_structp png_ptr,
1244 png_row_infop row_info));
1247 #ifdef PNG_READ_TRANSFORMS_SUPPORTED
1248 PNG_EXTERN void png_init_read_transformations PNGARG((png_structp png_ptr));
1251 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED
1252 PNG_EXTERN void png_push_read_chunk PNGARG((png_structp png_ptr,
1253 png_infop info_ptr));
1254 PNG_EXTERN void png_push_read_sig PNGARG((png_structp png_ptr,
1255 png_infop info_ptr));
1256 PNG_EXTERN void png_push_check_crc PNGARG((png_structp png_ptr));
1257 PNG_EXTERN void png_push_crc_skip PNGARG((png_structp png_ptr,
1258 png_uint_32 length));
1259 PNG_EXTERN void png_push_crc_finish PNGARG((png_structp png_ptr));
1260 PNG_EXTERN void png_push_save_buffer PNGARG((png_structp png_ptr));
1261 PNG_EXTERN void png_push_restore_buffer PNGARG((png_structp png_ptr,
1262 png_bytep buffer, png_size_t buffer_length));
1263 PNG_EXTERN void png_push_read_IDAT PNGARG((png_structp png_ptr));
1264 PNG_EXTERN void png_process_IDAT_data PNGARG((png_structp png_ptr,
1265 png_bytep buffer, png_size_t buffer_length));
1266 PNG_EXTERN void png_push_process_row PNGARG((png_structp png_ptr));
1267 PNG_EXTERN void png_push_handle_unknown PNGARG((png_structp png_ptr,
1268 png_infop info_ptr, png_uint_32 length));
1269 PNG_EXTERN void png_push_have_info PNGARG((png_structp png_ptr,
1270 png_infop info_ptr));
1271 PNG_EXTERN void png_push_have_end PNGARG((png_structp png_ptr,
1272 png_infop info_ptr));
1273 PNG_EXTERN void png_push_have_row PNGARG((png_structp png_ptr, png_bytep row));
1274 PNG_EXTERN void png_push_read_end PNGARG((png_structp png_ptr,
1275 png_infop info_ptr));
1276 PNG_EXTERN void png_process_some_data PNGARG((png_structp png_ptr,
1277 png_infop info_ptr));
1278 PNG_EXTERN void png_read_push_finish_row PNGARG((png_structp png_ptr));
1279 # ifdef PNG_READ_tEXt_SUPPORTED
1280 PNG_EXTERN void png_push_handle_tEXt PNGARG((png_structp png_ptr,
1281 png_infop info_ptr, png_uint_32 length));
1282 PNG_EXTERN void png_push_read_tEXt PNGARG((png_structp png_ptr,
1283 png_infop info_ptr));
1285 # ifdef PNG_READ_zTXt_SUPPORTED
1286 PNG_EXTERN void png_push_handle_zTXt PNGARG((png_structp png_ptr,
1287 png_infop info_ptr, png_uint_32 length));
1288 PNG_EXTERN void png_push_read_zTXt PNGARG((png_structp png_ptr,
1289 png_infop info_ptr));
1291 # ifdef PNG_READ_iTXt_SUPPORTED
1292 PNG_EXTERN void png_push_handle_iTXt PNGARG((png_structp png_ptr,
1293 png_infop info_ptr, png_uint_32 length));
1294 PNG_EXTERN void png_push_read_iTXt PNGARG((png_structp png_ptr,
1295 png_infop info_ptr));
1298 #endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
1300 #ifdef PNG_MNG_FEATURES_SUPPORTED
1301 PNG_EXTERN void png_do_read_intrapixel PNGARG((png_row_infop row_info,
1303 PNG_EXTERN void png_do_write_intrapixel PNGARG((png_row_infop row_info,
1307 /* Added at libpng version 1.4.0 */
1308 #ifdef PNG_CHECK_cHRM_SUPPORTED
1309 PNG_EXTERN int png_check_cHRM_fixed PNGARG((png_structp png_ptr,
1310 png_fixed_point int_white_x, png_fixed_point int_white_y,
1311 png_fixed_point int_red_x, png_fixed_point int_red_y, png_fixed_point
1312 int_green_x, png_fixed_point int_green_y, png_fixed_point int_blue_x,
1313 png_fixed_point int_blue_y));
1316 #ifdef PNG_CHECK_cHRM_SUPPORTED
1317 /* Added at libpng version 1.2.34 and 1.4.0 */
1318 /* Currently only used by png_check_cHRM_fixed */
1319 PNG_EXTERN void png_64bit_product PNGARG((long v1, long v2,
1320 unsigned long *hi_product, unsigned long *lo_product));
1323 #ifdef PNG_cHRM_SUPPORTED
1324 /* Added at libpng version 1.5.5 */
1325 typedef struct png_xy
1327 png_fixed_point redx, redy;
1328 png_fixed_point greenx, greeny;
1329 png_fixed_point bluex, bluey;
1330 png_fixed_point whitex, whitey;
1333 typedef struct png_XYZ
1335 png_fixed_point redX, redY, redZ;
1336 png_fixed_point greenX, greenY, greenZ;
1337 png_fixed_point blueX, blueY, blueZ;
1340 /* The conversion APIs return 0 on success, non-zero on a parameter error. They
1341 * allow conversion between the above representations of a color encoding. When
1342 * converting from XYZ end points to chromaticities the absolute magnitude of
1343 * the end points is lost, when converting back the sum of the Y values of the
1344 * three end points will be 1.0
1346 PNG_EXTERN int png_xy_from_XYZ PNGARG((png_xy *xy, png_XYZ XYZ));
1347 PNG_EXTERN int png_XYZ_from_xy PNGARG((png_XYZ *XYZ, png_xy xy));
1348 PNG_EXTERN int png_XYZ_from_xy_checked PNGARG((png_structp png_ptr,
1349 png_XYZ *XYZ, png_xy xy));
1352 /* Added at libpng version 1.4.0 */
1353 PNG_EXTERN void png_check_IHDR PNGARG((png_structp png_ptr,
1354 png_uint_32 width, png_uint_32 height, int bit_depth,
1355 int color_type, int interlace_type, int compression_type,
1358 /* Free all memory used by the read (old method - NOT DLL EXPORTED) */
1359 PNG_EXTERN void png_read_destroy PNGARG((png_structp png_ptr,
1360 png_infop info_ptr, png_infop end_info_ptr));
1362 /* Free any memory used in png_ptr struct (old method - NOT DLL EXPORTED) */
1363 PNG_EXTERN void png_write_destroy PNGARG((png_structp png_ptr));
1365 #ifdef USE_FAR_KEYWORD /* memory model conversion function */
1366 PNG_EXTERN void *png_far_to_near PNGARG((png_structp png_ptr, png_voidp ptr,
1368 #endif /* USE_FAR_KEYWORD */
1370 #if defined(PNG_FLOATING_POINT_SUPPORTED) && defined(PNG_ERROR_TEXT_SUPPORTED)
1371 PNG_EXTERN PNG_FUNCTION(void, png_fixed_error, (png_structp png_ptr,
1372 png_const_charp name),PNG_NORETURN);
1375 /* Puts 'string' into 'buffer' at buffer[pos], taking care never to overwrite
1376 * the end. Always leaves the buffer nul terminated. Never errors out (and
1377 * there is no error code.)
1379 PNG_EXTERN size_t png_safecat(png_charp buffer, size_t bufsize, size_t pos,
1380 png_const_charp string);
1382 /* Various internal functions to handle formatted warning messages, currently
1383 * only implemented for warnings.
1385 #if defined(PNG_WARNINGS_SUPPORTED) || defined(PNG_TIME_RFC1123_SUPPORTED)
1386 /* Utility to dump an unsigned value into a buffer, given a start pointer and
1387 * and end pointer (which should point just *beyond* the end of the buffer!)
1388 * Returns the pointer to the start of the formatted string. This utility only
1389 * does unsigned values.
1391 PNG_EXTERN png_charp png_format_number(png_const_charp start, png_charp end,
1392 int format, png_alloc_size_t number);
1394 /* Convenience macro that takes an array: */
1395 #define PNG_FORMAT_NUMBER(buffer,format,number) \
1396 png_format_number(buffer, buffer + (sizeof buffer), format, number)
1398 /* Suggested size for a number buffer (enough for 64 bits and a sign!) */
1399 #define PNG_NUMBER_BUFFER_SIZE 24
1401 /* These are the integer formats currently supported, the name is formed from
1402 * the standard printf(3) format string.
1404 #define PNG_NUMBER_FORMAT_u 1 /* chose unsigned API! */
1405 #define PNG_NUMBER_FORMAT_02u 2
1406 #define PNG_NUMBER_FORMAT_d 1 /* chose signed API! */
1407 #define PNG_NUMBER_FORMAT_02d 2
1408 #define PNG_NUMBER_FORMAT_x 3
1409 #define PNG_NUMBER_FORMAT_02x 4
1410 #define PNG_NUMBER_FORMAT_fixed 5 /* choose the signed API */
1413 #ifdef PNG_WARNINGS_SUPPORTED
1414 /* New defines and members adding in libpng-1.5.4 */
1415 # define PNG_WARNING_PARAMETER_SIZE 32
1416 # define PNG_WARNING_PARAMETER_COUNT 8
1418 /* An l-value of this type has to be passed to the APIs below to cache the
1419 * values of the parameters to a formatted warning message.
1421 typedef char png_warning_parameters[PNG_WARNING_PARAMETER_COUNT][
1422 PNG_WARNING_PARAMETER_SIZE];
1424 PNG_EXTERN void png_warning_parameter(png_warning_parameters p, int number,
1425 png_const_charp string);
1426 /* Parameters are limited in size to PNG_WARNING_PARAMETER_SIZE characters,
1427 * including the trailing '\0'.
1429 PNG_EXTERN void png_warning_parameter_unsigned(png_warning_parameters p,
1430 int number, int format, png_alloc_size_t value);
1431 /* Use png_alloc_size_t because it is an unsigned type as big as any we
1432 * need to output. Use the following for a signed value.
1434 PNG_EXTERN void png_warning_parameter_signed(png_warning_parameters p,
1435 int number, int format, png_int_32 value);
1437 PNG_EXTERN void png_formatted_warning(png_structp png_ptr,
1438 png_warning_parameters p, png_const_charp message);
1439 /* 'message' follows the X/Open approach of using @1, @2 to insert
1440 * parameters previously supplied using the above functions. Errors in
1441 * specifying the paramters will simple result in garbage substitutions.
1445 /* ASCII to FP interfaces, currently only implemented if sCAL
1446 * support is required.
1448 #if defined(PNG_READ_sCAL_SUPPORTED)
1449 /* MAX_DIGITS is actually the maximum number of characters in an sCAL
1450 * width or height, derived from the precision (number of significant
1451 * digits - a build time settable option) and assumpitions about the
1452 * maximum ridiculous exponent.
1454 #define PNG_sCAL_MAX_DIGITS (PNG_sCAL_PRECISION+1/*.*/+1/*E*/+10/*exponent*/)
1456 #ifdef PNG_FLOATING_POINT_SUPPORTED
1457 PNG_EXTERN void png_ascii_from_fp PNGARG((png_structp png_ptr, png_charp ascii,
1458 png_size_t size, double fp, unsigned int precision));
1459 #endif /* FLOATING_POINT */
1461 #ifdef PNG_FIXED_POINT_SUPPORTED
1462 PNG_EXTERN void png_ascii_from_fixed PNGARG((png_structp png_ptr,
1463 png_charp ascii, png_size_t size, png_fixed_point fp));
1464 #endif /* FIXED_POINT */
1465 #endif /* READ_sCAL */
1467 #if defined(PNG_sCAL_SUPPORTED) || defined(PNG_pCAL_SUPPORTED)
1468 /* An internal API to validate the format of a floating point number.
1469 * The result is the index of the next character. If the number is
1470 * not valid it will be the index of a character in the supposed number.
1472 * The format of a number is defined in the PNG extensions specification
1473 * and this API is strictly conformant to that spec, not anyone elses!
1475 * The format as a regular expression is:
1477 * [+-]?[0-9]+.?([Ee][+-]?[0-9]+)?
1481 * [+-]?.[0-9]+(.[0-9]+)?([Ee][+-]?[0-9]+)?
1483 * The complexity is that either integer or fraction must be present and the
1484 * fraction is permitted to have no digits only if the integer is present.
1486 * NOTE: The dangling E problem.
1487 * There is a PNG valid floating point number in the following:
1489 * PNG floating point numb1.ers are not greedy.
1491 * Working this out requires *TWO* character lookahead (because of the
1492 * sign), the parser does not do this - it will fail at the 'r' - this
1493 * doesn't matter for PNG sCAL chunk values, but it requires more care
1494 * if the value were ever to be embedded in something more complex. Use
1495 * ANSI-C strtod if you need the lookahead.
1497 /* State table for the parser. */
1498 #define PNG_FP_INTEGER 0 /* before or in integer */
1499 #define PNG_FP_FRACTION 1 /* before or in fraction */
1500 #define PNG_FP_EXPONENT 2 /* before or in exponent */
1501 #define PNG_FP_STATE 3 /* mask for the above */
1502 #define PNG_FP_SAW_SIGN 4 /* Saw +/- in current state */
1503 #define PNG_FP_SAW_DIGIT 8 /* Saw a digit in current state */
1504 #define PNG_FP_SAW_DOT 16 /* Saw a dot in current state */
1505 #define PNG_FP_SAW_E 32 /* Saw an E (or e) in current state */
1506 #define PNG_FP_SAW_ANY 60 /* Saw any of the above 4 */
1508 /* These three values don't affect the parser. They are set but not used.
1510 #define PNG_FP_WAS_VALID 64 /* Preceding substring is a valid fp number */
1511 #define PNG_FP_NEGATIVE 128 /* A negative number, including "-0" */
1512 #define PNG_FP_NONZERO 256 /* A non-zero value */
1513 #define PNG_FP_STICKY 448 /* The above three flags */
1515 /* This is available for the caller to store in 'state' if required. Do not
1516 * call the parser after setting it (the parser sometimes clears it.)
1518 #define PNG_FP_INVALID 512 /* Available for callers as a distinct value */
1520 /* Result codes for the parser (boolean - true meants ok, false means
1523 #define PNG_FP_MAYBE 0 /* The number may be valid in the future */
1524 #define PNG_FP_OK 1 /* The number is valid */
1526 /* Tests on the sticky non-zero and negative flags. To pass these checks
1527 * the state must also indicate that the whole number is valid - this is
1528 * achieved by testing PNG_FP_SAW_DIGIT (see the implementation for why this
1529 * is equivalent to PNG_FP_OK above.)
1531 #define PNG_FP_NZ_MASK (PNG_FP_SAW_DIGIT | PNG_FP_NEGATIVE | PNG_FP_NONZERO)
1532 /* NZ_MASK: the string is valid and a non-zero negative value */
1533 #define PNG_FP_Z_MASK (PNG_FP_SAW_DIGIT | PNG_FP_NONZERO)
1534 /* Z MASK: the string is valid and a non-zero value. */
1535 /* PNG_FP_SAW_DIGIT: the string is valid. */
1536 #define PNG_FP_IS_ZERO(state) (((state) & PNG_FP_Z_MASK) == PNG_FP_SAW_DIGIT)
1537 #define PNG_FP_IS_POSITIVE(state) (((state) & PNG_FP_NZ_MASK) == PNG_FP_Z_MASK)
1538 #define PNG_FP_IS_NEGATIVE(state) (((state) & PNG_FP_NZ_MASK) == PNG_FP_NZ_MASK)
1540 /* The actual parser. This can be called repeatedly, it updates
1541 * the index into the string and the state variable (which must
1542 * be initialzed to 0). It returns a result code, as above. There
1543 * is no point calling the parser any more if it fails to advance to
1544 * the end of the string - it is stuck on an invalid character (or
1545 * terminated by '\0').
1547 * Note that the pointer will consume an E or even an E+ then leave
1548 * a 'maybe' state even though a preceding integer.fraction is valid.
1549 * The PNG_FP_WAS_VALID flag indicates that a preceding substring was
1550 * a valid number. It's possible to recover from this by calling
1551 * the parser again (from the start, with state 0) but with a string
1552 * that omits the last character (i.e. set the size to the index of
1553 * the problem character.) This has not been tested within libpng.
1555 PNG_EXTERN int png_check_fp_number PNGARG((png_const_charp string,
1556 png_size_t size, int *statep, png_size_tp whereami));
1558 /* This is the same but it checks a complete string and returns true
1559 * only if it just contains a floating point number. As of 1.5.4 this
1560 * function also returns the state at the end of parsing the number if
1561 * it was valid (otherwise it returns 0.) This can be used for testing
1562 * for negative or zero values using the sticky flag.
1564 PNG_EXTERN int png_check_fp_string PNGARG((png_const_charp string,
1566 #endif /* pCAL || sCAL */
1568 #if defined(PNG_READ_GAMMA_SUPPORTED) ||\
1569 defined(PNG_INCH_CONVERSIONS_SUPPORTED) || defined(PNG_READ_pHYs_SUPPORTED)
1570 /* Added at libpng version 1.5.0 */
1571 /* This is a utility to provide a*times/div (rounded) and indicate
1572 * if there is an overflow. The result is a boolean - false (0)
1573 * for overflow, true (1) if no overflow, in which case *res
1576 PNG_EXTERN int png_muldiv PNGARG((png_fixed_point_p res, png_fixed_point a,
1577 png_int_32 multiplied_by, png_int_32 divided_by));
1580 #if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_INCH_CONVERSIONS_SUPPORTED)
1581 /* Same deal, but issue a warning on overflow and return 0. */
1582 PNG_EXTERN png_fixed_point png_muldiv_warn PNGARG((png_structp png_ptr,
1583 png_fixed_point a, png_int_32 multiplied_by, png_int_32 divided_by));
1586 #ifdef PNG_READ_GAMMA_SUPPORTED
1587 /* Calculate a reciprocal - used for gamma values. This returns
1588 * 0 if the argument is 0 in order to maintain an undefined value,
1589 * there are no warnings.
1591 PNG_EXTERN png_fixed_point png_reciprocal PNGARG((png_fixed_point a));
1593 /* The same but gives a reciprocal of the product of two fixed point
1594 * values. Accuracy is suitable for gamma calculations but this is
1595 * not exact - use png_muldiv for that.
1597 PNG_EXTERN png_fixed_point png_reciprocal2 PNGARG((png_fixed_point a,
1598 png_fixed_point b));
1601 #ifdef PNG_READ_GAMMA_SUPPORTED
1602 /* Internal fixed point gamma correction. These APIs are called as
1603 * required to convert single values - they don't need to be fast,
1604 * they are not used when processing image pixel values.
1606 * While the input is an 'unsigned' value it must actually be the
1607 * correct bit value - 0..255 or 0..65535 as required.
1609 PNG_EXTERN png_uint_16 png_gamma_correct PNGARG((png_structp png_ptr,
1610 unsigned int value, png_fixed_point gamma_value));
1611 PNG_EXTERN int png_gamma_significant PNGARG((png_fixed_point gamma_value));
1612 PNG_EXTERN png_uint_16 png_gamma_16bit_correct PNGARG((unsigned int value,
1613 png_fixed_point gamma_value));
1614 PNG_EXTERN png_byte png_gamma_8bit_correct PNGARG((unsigned int value,
1615 png_fixed_point gamma_value));
1616 PNG_EXTERN void png_destroy_gamma_table(png_structp png_ptr);
1617 PNG_EXTERN void png_build_gamma_table PNGARG((png_structp png_ptr,
1621 /* Maintainer: Put new private prototypes here ^ and in libpngpf.3 */
1623 #include "pngdebug.h"
1629 #endif /* PNGPRIV_H */