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Diffstat (limited to 'contrib/ffmpeg/libavcodec/gifdec.c')
-rw-r--r--contrib/ffmpeg/libavcodec/gifdec.c343
1 files changed, 0 insertions, 343 deletions
diff --git a/contrib/ffmpeg/libavcodec/gifdec.c b/contrib/ffmpeg/libavcodec/gifdec.c
deleted file mode 100644
index 3e8a3e6bc..000000000
--- a/contrib/ffmpeg/libavcodec/gifdec.c
+++ /dev/null
@@ -1,343 +0,0 @@
-/*
- * GIF decoder
- * Copyright (c) 2003 Fabrice Bellard.
- * Copyright (c) 2006 Baptiste Coudurier.
- *
- * This file is part of FFmpeg.
- *
- * FFmpeg is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * FFmpeg 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
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with FFmpeg; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-//#define DEBUG
-
-#include "avcodec.h"
-#include "bytestream.h"
-#include "lzw.h"
-
-#define GCE_DISPOSAL_NONE 0
-#define GCE_DISPOSAL_INPLACE 1
-#define GCE_DISPOSAL_BACKGROUND 2
-#define GCE_DISPOSAL_RESTORE 3
-
-typedef struct GifState {
- AVFrame picture;
- int screen_width;
- int screen_height;
- int bits_per_pixel;
- int background_color_index;
- int transparent_color_index;
- int color_resolution;
- uint32_t *image_palette;
-
- /* after the frame is displayed, the disposal method is used */
- int gce_disposal;
- /* delay during which the frame is shown */
- int gce_delay;
-
- /* LZW compatible decoder */
- uint8_t *bytestream;
- uint8_t *bytestream_end;
- LZWState *lzw;
-
- /* aux buffers */
- uint8_t global_palette[256 * 3];
- uint8_t local_palette[256 * 3];
-
- AVCodecContext* avctx;
-} GifState;
-
-static const uint8_t gif87a_sig[6] = "GIF87a";
-static const uint8_t gif89a_sig[6] = "GIF89a";
-
-static int gif_read_image(GifState *s)
-{
- int left, top, width, height, bits_per_pixel, code_size, flags;
- int is_interleaved, has_local_palette, y, pass, y1, linesize, n, i;
- uint8_t *ptr, *spal, *palette, *ptr1;
-
- left = bytestream_get_le16(&s->bytestream);
- top = bytestream_get_le16(&s->bytestream);
- width = bytestream_get_le16(&s->bytestream);
- height = bytestream_get_le16(&s->bytestream);
- flags = bytestream_get_byte(&s->bytestream);
- is_interleaved = flags & 0x40;
- has_local_palette = flags & 0x80;
- bits_per_pixel = (flags & 0x07) + 1;
-#ifdef DEBUG
- dprintf(s->avctx, "gif: image x=%d y=%d w=%d h=%d\n", left, top, width, height);
-#endif
-
- if (has_local_palette) {
- bytestream_get_buffer(&s->bytestream, s->local_palette, 3 * (1 << bits_per_pixel));
- palette = s->local_palette;
- } else {
- palette = s->global_palette;
- bits_per_pixel = s->bits_per_pixel;
- }
-
- /* verify that all the image is inside the screen dimensions */
- if (left + width > s->screen_width ||
- top + height > s->screen_height)
- return AVERROR(EINVAL);
-
- /* build the palette */
- n = (1 << bits_per_pixel);
- spal = palette;
- for(i = 0; i < n; i++) {
- s->image_palette[i] = (0xff << 24) |
- (spal[0] << 16) | (spal[1] << 8) | (spal[2]);
- spal += 3;
- }
- for(; i < 256; i++)
- s->image_palette[i] = (0xff << 24);
- /* handle transparency */
- if (s->transparent_color_index >= 0)
- s->image_palette[s->transparent_color_index] = 0;
-
- /* now get the image data */
- code_size = bytestream_get_byte(&s->bytestream);
- ff_lzw_decode_init(s->lzw, code_size, s->bytestream,
- s->bytestream_end - s->bytestream, FF_LZW_GIF);
-
- /* read all the image */
- linesize = s->picture.linesize[0];
- ptr1 = s->picture.data[0] + top * linesize + left;
- ptr = ptr1;
- pass = 0;
- y1 = 0;
- for (y = 0; y < height; y++) {
- ff_lzw_decode(s->lzw, ptr, width);
- if (is_interleaved) {
- switch(pass) {
- default:
- case 0:
- case 1:
- y1 += 8;
- ptr += linesize * 8;
- if (y1 >= height) {
- y1 = 4;
- if (pass == 0)
- ptr = ptr1 + linesize * 4;
- else
- ptr = ptr1 + linesize * 2;
- pass++;
- }
- break;
- case 2:
- y1 += 4;
- ptr += linesize * 4;
- if (y1 >= height) {
- y1 = 1;
- ptr = ptr1 + linesize;
- pass++;
- }
- break;
- case 3:
- y1 += 2;
- ptr += linesize * 2;
- break;
- }
- } else {
- ptr += linesize;
- }
- }
- /* read the garbage data until end marker is found */
- ff_lzw_decode_tail(s->lzw);
- s->bytestream = ff_lzw_cur_ptr(s->lzw);
- return 0;
-}
-
-static int gif_read_extension(GifState *s)
-{
- int ext_code, ext_len, i, gce_flags, gce_transparent_index;
-
- /* extension */
- ext_code = bytestream_get_byte(&s->bytestream);
- ext_len = bytestream_get_byte(&s->bytestream);
-#ifdef DEBUG
- dprintf(s->avctx, "gif: ext_code=0x%x len=%d\n", ext_code, ext_len);
-#endif
- switch(ext_code) {
- case 0xf9:
- if (ext_len != 4)
- goto discard_ext;
- s->transparent_color_index = -1;
- gce_flags = bytestream_get_byte(&s->bytestream);
- s->gce_delay = bytestream_get_le16(&s->bytestream);
- gce_transparent_index = bytestream_get_byte(&s->bytestream);
- if (gce_flags & 0x01)
- s->transparent_color_index = gce_transparent_index;
- else
- s->transparent_color_index = -1;
- s->gce_disposal = (gce_flags >> 2) & 0x7;
-#ifdef DEBUG
- dprintf(s->avctx, "gif: gce_flags=%x delay=%d tcolor=%d disposal=%d\n",
- gce_flags, s->gce_delay,
- s->transparent_color_index, s->gce_disposal);
-#endif
- ext_len = bytestream_get_byte(&s->bytestream);
- break;
- }
-
- /* NOTE: many extension blocks can come after */
- discard_ext:
- while (ext_len != 0) {
- for (i = 0; i < ext_len; i++)
- bytestream_get_byte(&s->bytestream);
- ext_len = bytestream_get_byte(&s->bytestream);
-#ifdef DEBUG
- dprintf(s->avctx, "gif: ext_len1=%d\n", ext_len);
-#endif
- }
- return 0;
-}
-
-static int gif_read_header1(GifState *s)
-{
- uint8_t sig[6];
- int v, n;
- int has_global_palette;
-
- if (s->bytestream_end < s->bytestream + 13)
- return -1;
-
- /* read gif signature */
- bytestream_get_buffer(&s->bytestream, sig, 6);
- if (memcmp(sig, gif87a_sig, 6) != 0 &&
- memcmp(sig, gif89a_sig, 6) != 0)
- return -1;
-
- /* read screen header */
- s->transparent_color_index = -1;
- s->screen_width = bytestream_get_le16(&s->bytestream);
- s->screen_height = bytestream_get_le16(&s->bytestream);
- if( (unsigned)s->screen_width > 32767
- || (unsigned)s->screen_height > 32767){
- av_log(NULL, AV_LOG_ERROR, "picture size too large\n");
- return -1;
- }
-
- v = bytestream_get_byte(&s->bytestream);
- s->color_resolution = ((v & 0x70) >> 4) + 1;
- has_global_palette = (v & 0x80);
- s->bits_per_pixel = (v & 0x07) + 1;
- s->background_color_index = bytestream_get_byte(&s->bytestream);
- bytestream_get_byte(&s->bytestream); /* ignored */
-#ifdef DEBUG
- dprintf(s->avctx, "gif: screen_w=%d screen_h=%d bpp=%d global_palette=%d\n",
- s->screen_width, s->screen_height, s->bits_per_pixel,
- has_global_palette);
-#endif
- if (has_global_palette) {
- n = 1 << s->bits_per_pixel;
- if (s->bytestream_end < s->bytestream + n * 3)
- return -1;
- bytestream_get_buffer(&s->bytestream, s->global_palette, n * 3);
- }
- return 0;
-}
-
-static int gif_parse_next_image(GifState *s)
-{
- while (s->bytestream < s->bytestream_end) {
- int code = bytestream_get_byte(&s->bytestream);
-#ifdef DEBUG
- dprintf(s->avctx, "gif: code=%02x '%c'\n", code, code);
-#endif
- switch (code) {
- case ',':
- if (gif_read_image(s) < 0)
- return -1;
- return 0;
- case ';':
- /* end of image */
- return -1;
- case '!':
- if (gif_read_extension(s) < 0)
- return -1;
- break;
- default:
- /* error or errneous EOF */
- return -1;
- }
- }
- return -1;
-}
-
-static int gif_decode_init(AVCodecContext *avctx)
-{
- GifState *s = avctx->priv_data;
-
- s->avctx = avctx;
-
- avcodec_get_frame_defaults(&s->picture);
- avctx->coded_frame= &s->picture;
- s->picture.data[0] = NULL;
- ff_lzw_decode_open(&s->lzw);
- return 0;
-}
-
-static int gif_decode_frame(AVCodecContext *avctx, void *data, int *data_size, uint8_t *buf, int buf_size)
-{
- GifState *s = avctx->priv_data;
- AVFrame *picture = data;
- int ret;
-
- s->bytestream = buf;
- s->bytestream_end = buf + buf_size;
- if (gif_read_header1(s) < 0)
- return -1;
-
- avctx->pix_fmt = PIX_FMT_PAL8;
- if (avcodec_check_dimensions(avctx, s->screen_width, s->screen_height))
- return -1;
- avcodec_set_dimensions(avctx, s->screen_width, s->screen_height);
-
- if (s->picture.data[0])
- avctx->release_buffer(avctx, &s->picture);
- if (avctx->get_buffer(avctx, &s->picture) < 0) {
- av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
- return -1;
- }
- s->image_palette = (uint32_t *)s->picture.data[1];
- ret = gif_parse_next_image(s);
- if (ret < 0)
- return ret;
-
- *picture = s->picture;
- *data_size = sizeof(AVPicture);
- return s->bytestream - buf;
-}
-
-static int gif_decode_close(AVCodecContext *avctx)
-{
- GifState *s = avctx->priv_data;
-
- ff_lzw_decode_close(&s->lzw);
- if(s->picture.data[0])
- avctx->release_buffer(avctx, &s->picture);
- return 0;
-}
-
-AVCodec gif_decoder = {
- "gif",
- CODEC_TYPE_VIDEO,
- CODEC_ID_GIF,
- sizeof(GifState),
- gif_decode_init,
- NULL,
- gif_decode_close,
- gif_decode_frame,
-};
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