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-rw-r--r--examples/decode_gif.c221
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diff --git a/examples/decode_gif.c b/examples/decode_gif.c
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+++ b/examples/decode_gif.c
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+/*
+ * Copyright 2008 Sean Fox <dyntryx@gmail.com>
+ * Copyright 2008 James Bursa <james@netsurf-browser.org>
+ *
+ * This file is part of NetSurf, http://www.netsurf-browser.org/
+ *
+ * NetSurf is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * NetSurf is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <assert.h>
+#include <errno.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <libnsgif.h>
+
+char *load_file(const char *path, size_t *data_size);
+void die(const char *context, int code);
+void *bitmap_create(int width, int height);
+void bitmap_set_opaque(void *bitmap, bool opaque);
+bool bitmap_test_opaque(void *bitmap);
+char *bitmap_get_buffer(void *bitmap);
+void bitmap_destroy(void *bitmap);
+void bitmap_modified(void *bitmap);
+
+
+gif_bitmap_callback_vt bitmap_callbacks = {
+ bitmap_create,
+ bitmap_destroy,
+ bitmap_get_buffer,
+ bitmap_set_opaque,
+ bitmap_test_opaque,
+ bitmap_modified
+};
+
+
+int main(int argc, char *argv[])
+{
+ struct gif_animation gif;
+ size_t size;
+ int code;
+ unsigned int i;
+
+ if (argc != 2) {
+ fprintf(stderr, "Usage: %s image.gif\n", argv[0]);
+ return 1;
+ }
+
+ /* load file into memory */
+ char *data = load_file(argv[1], &size);
+
+ /* initialise gif_animation structure */
+ gif.buffer_size = size;
+ gif.gif_data = (unsigned char *) data;
+ gif.buffer_position = 0;
+
+ /* begin decoding */
+ do {
+ code = gif_initialise(&gif, &bitmap_callbacks);
+ if (code != 0 && code != 1)
+ die("gif_initialise", code);
+ } while (code != 1);
+
+ printf("P3\n");
+ printf("# %s\n", argv[1]);
+ printf("# width %u \n", gif.width);
+ printf("# height %u \n", gif.height);
+ printf("# frame_count %u \n", gif.frame_count);
+ printf("# frame_count_partial %u \n", gif.frame_count_partial);
+ printf("# background_colour %x \n", gif.background_colour);
+ printf("# loop_count %u \n", gif.loop_count);
+ printf("%u %u 256\n", gif.width, gif.height * gif.frame_count);
+
+ /* decode the frames */
+ for (i = 0; i != gif.frame_count; i++) {
+ unsigned int row, col;
+ char *image;
+
+ code = gif_decode_frame(&gif, i, &bitmap_callbacks);
+ if (code != 0)
+ die("gif_decode_frame", code);
+
+ printf("# frame %u:\n", i);
+ image = (char *) gif.frame_image;
+ for (row = 0; row != gif.height; row++) {
+ for (col = 0; col != gif.width; col++) {
+ size_t z = (row * gif.width + col) * 4;
+ printf("%u %u %u ",
+ (unsigned char) image[z],
+ (unsigned char) image[z + 1],
+ (unsigned char) image[z + 2]);
+ }
+ printf("\n");
+ }
+ }
+
+ return 0;
+}
+
+
+char *load_file(const char *path, size_t *data_size)
+{
+ FILE *fd;
+ struct stat sb;
+ char *buffer;
+ size_t size;
+ size_t n;
+
+ fd = fopen(path, "rb");
+ if (!fd) {
+ perror(path);
+ exit(EXIT_FAILURE);
+ }
+
+ if (stat(path, &sb)) {
+ perror(path);
+ exit(EXIT_FAILURE);
+ }
+ size = sb.st_size;
+
+ buffer = malloc(size);
+ if (!buffer) {
+ fprintf(stderr, "Unable to allocate %lld bytes\n",
+ (long long) size);
+ exit(EXIT_FAILURE);
+ }
+
+ n = fread(buffer, 1, size, fd);
+ if (n != size) {
+ perror(path);
+ exit(EXIT_FAILURE);
+ }
+
+ fclose(fd);
+
+ *data_size = size;
+ return buffer;
+}
+
+
+void die(const char *context, int code)
+{
+ fprintf(stderr, "%s failed: ", context);
+ switch (code)
+ {
+ case GIF_INSUFFICIENT_FRAME_DATA:
+ fprintf(stderr, "GIF_INSUFFICIENT_FRAME_DATA");
+ break;
+ case GIF_FRAME_DATA_ERROR:
+ fprintf(stderr, "GIF_FRAME_DATA_ERROR");
+ break;
+ case GIF_INSUFFICIENT_DATA:
+ fprintf(stderr, "GIF_INSUFFICIENT_DATA");
+ break;
+ case GIF_DATA_ERROR:
+ fprintf(stderr, "GIF_DATA_ERROR");
+ break;
+ case GIF_INSUFFICIENT_MEMORY:
+ fprintf(stderr, "GIF_INSUFFICIENT_MEMORY");
+ break;
+ default:
+ fprintf(stderr, "unknown code %i", code);
+ break;
+ }
+ fprintf(stderr, "\n");
+ exit(EXIT_FAILURE);
+}
+
+
+void *bitmap_create(int width, int height)
+{
+ return calloc(width * height, 4);
+}
+
+
+void bitmap_set_opaque(void *bitmap, bool opaque)
+{
+ (void) opaque; /* unused */
+ assert(bitmap);
+}
+
+
+bool bitmap_test_opaque(void *bitmap)
+{
+ assert(bitmap);
+ return false;
+}
+
+
+char *bitmap_get_buffer(void *bitmap)
+{
+ assert(bitmap);
+ return bitmap;
+}
+
+
+void bitmap_destroy(void *bitmap)
+{
+ assert(bitmap);
+ free(bitmap);
+}
+
+
+void bitmap_modified(void *bitmap)
+{
+ assert(bitmap);
+ return;
+}
+