--- /dev/null
+/**************************************************************************
+ *
+ * Copyright 2011 Jose Fonseca
+ * Copyright 2008-2010 VMware, Inc.
+ * All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ **************************************************************************/
+
+
+#include <zlib.h>
+#include <png.h>
+
+#include <assert.h>
+#include <stdint.h>
+#include <stdlib.h>
+
+#include <fstream>
+
+#include "image.hpp"
+
+
+namespace image {
+
+
+static const int png_compression_level = Z_BEST_SPEED;
+
+
+static void
+pngWriteCallback(png_structp png_ptr, png_bytep data, png_size_t length)
+{
+ std::ostream *os = (std::ostream *) png_get_io_ptr(png_ptr);
+ os->write((const char *)data, length);
+}
+
+bool
+Image::writePNG(std::ostream &os) const
+{
+ png_structp png_ptr;
+ png_infop info_ptr;
+ int color_type;
+
+ switch (channels) {
+ case 4:
+ color_type = PNG_COLOR_TYPE_RGB_ALPHA;
+ break;
+ case 3:
+ color_type = PNG_COLOR_TYPE_RGB;
+ break;
+ case 2:
+ color_type = PNG_COLOR_TYPE_GRAY_ALPHA;
+ break;
+ case 1:
+ color_type = PNG_COLOR_TYPE_GRAY;
+ break;
+ default:
+ assert(0);
+ goto no_png;
+ }
+
+ png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
+ if (!png_ptr)
+ goto no_png;
+
+ info_ptr = png_create_info_struct(png_ptr);
+ if (!info_ptr) {
+ png_destroy_write_struct(&png_ptr, NULL);
+ goto no_png;
+ }
+
+ if (setjmp(png_jmpbuf(png_ptr))) {
+ png_destroy_write_struct(&png_ptr, &info_ptr);
+ goto no_png;
+ }
+
+ png_set_write_fn(png_ptr, &os, pngWriteCallback, NULL);
+
+ png_set_IHDR(png_ptr, info_ptr, width, height, 8,
+ color_type, PNG_INTERLACE_NONE,
+ PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
+
+ png_set_compression_level(png_ptr, png_compression_level);
+
+ png_write_info(png_ptr, info_ptr);
+
+ if (!flipped) {
+ for (unsigned y = 0; y < height; ++y) {
+ png_bytep row = (png_bytep)(pixels + y*width*channels);
+ png_write_rows(png_ptr, &row, 1);
+ }
+ } else {
+ unsigned y = height;
+ while (y--) {
+ png_bytep row = (png_bytep)(pixels + y*width*channels);
+ png_write_rows(png_ptr, &row, 1);
+ }
+ }
+
+ png_write_end(png_ptr, info_ptr);
+ png_destroy_write_struct(&png_ptr, &info_ptr);
+
+ return true;
+
+no_png:
+ return false;
+}
+
+
+Image *
+readPNG(const char *filename)
+{
+ FILE *fp;
+ png_structp png_ptr;
+ png_infop info_ptr;
+ png_infop end_info;
+ Image *image;
+
+ fp = fopen(filename, "rb");
+ if (!fp)
+ goto no_fp;
+
+ png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
+ if (!png_ptr)
+ goto no_png;
+
+ info_ptr = png_create_info_struct(png_ptr);
+ if (!info_ptr) {
+ png_destroy_read_struct(&png_ptr, NULL, NULL);
+ goto no_png;
+ }
+
+ end_info = png_create_info_struct(png_ptr);
+ if (!end_info) {
+ png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+ goto no_png;
+ }
+
+ if (setjmp(png_jmpbuf(png_ptr))) {
+ png_destroy_read_struct(&png_ptr, &info_ptr, &end_info);
+ goto no_png;
+ }
+
+ png_init_io(png_ptr, fp);
+
+ png_read_info(png_ptr, info_ptr);
+
+ png_uint_32 width, height;
+ int bit_depth, color_type, interlace_type, compression_type, filter_method;
+
+ png_get_IHDR(png_ptr, info_ptr,
+ &width, &height,
+ &bit_depth, &color_type, &interlace_type,
+ &compression_type, &filter_method);
+
+ image = new Image(width, height);
+ if (!image)
+ goto no_image;
+
+ /* Convert to RGBA8 */
+ 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);
+ if (bit_depth == 16)
+ png_set_strip_16(png_ptr);
+
+ for (unsigned y = 0; y < height; ++y) {
+ png_bytep row = (png_bytep)(image->pixels + y*width*4);
+ png_read_row(png_ptr, row, NULL);
+ }
+
+ png_read_end(png_ptr, info_ptr);
+ png_destroy_read_struct(&png_ptr, &info_ptr, &end_info);
+ fclose(fp);
+ return image;
+
+no_image:
+ png_destroy_read_struct(&png_ptr, &info_ptr, &end_info);
+no_png:
+ fclose(fp);
+no_fp:
+ return NULL;
+}
+
+
+
+} /* namespace image */
projects / apitrace / blobdiff