From 22e28216336da876e1fd17f380ce42eaf1446769 Mon Sep 17 00:00:00 2001 From: Tim Redfern Date: Mon, 17 Feb 2014 13:36:38 +0000 Subject: chasing indexing error --- ffmpeg/libavformat/gifdec.c | 334 -------------------------------------------- 1 file changed, 334 deletions(-) delete mode 100644 ffmpeg/libavformat/gifdec.c (limited to 'ffmpeg/libavformat/gifdec.c') diff --git a/ffmpeg/libavformat/gifdec.c b/ffmpeg/libavformat/gifdec.c deleted file mode 100644 index 2981bca..0000000 --- a/ffmpeg/libavformat/gifdec.c +++ /dev/null @@ -1,334 +0,0 @@ -/* - * GIF demuxer - * Copyright (c) 2012 Vitaliy E Sugrobov - * - * 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 - */ - -/** - * @file - * GIF demuxer. - */ - -#include "avformat.h" -#include "libavutil/intreadwrite.h" -#include "libavutil/opt.h" -#include "internal.h" -#include "libavcodec/gif.h" - -typedef struct GIFDemuxContext { - const AVClass *class; - /** - * Time span in hundredths of second before - * the next frame should be drawn on screen. - */ - int delay; - /** - * Minimum allowed delay between frames in hundredths of - * second. Values below this threshold considered to be - * invalid and set to value of default_delay. - */ - int min_delay; - int default_delay; - - /** - * loop options - */ - int total_iter; - int iter_count; - int ignore_loop; -} GIFDemuxContext; - -/** - * Major web browsers display gifs at ~10-15fps when rate - * is not explicitly set or have too low values. We assume default rate to be 10. - * Default delay = 100hundredths of second / 10fps = 10hos per frame. - */ -#define GIF_DEFAULT_DELAY 10 -/** - * By default delay values less than this threshold considered to be invalid. - */ -#define GIF_MIN_DELAY 2 - -static int gif_probe(AVProbeData *p) -{ - /* check magick */ - if (memcmp(p->buf, gif87a_sig, 6) && memcmp(p->buf, gif89a_sig, 6)) - return 0; - - /* width or height contains zero? */ - if (!AV_RL16(&p->buf[6]) || !AV_RL16(&p->buf[8])) - return 0; - - return AVPROBE_SCORE_MAX; -} - -static int resync(AVIOContext *pb) -{ - int i; - for (i = 0; i < 6; i++) { - int b = avio_r8(pb); - if (b != gif87a_sig[i] && b != gif89a_sig[i]) - i = -(b != 'G'); - if (url_feof(pb)) - return AVERROR_EOF; - } - return 0; -} - -static int gif_read_header(AVFormatContext *s) -{ - GIFDemuxContext *gdc = s->priv_data; - AVIOContext *pb = s->pb; - AVStream *st; - int width, height, ret; - - if ((ret = resync(pb)) < 0) - return ret; - - gdc->delay = gdc->default_delay; - width = avio_rl16(pb); - height = avio_rl16(pb); - - if (width == 0 || height == 0) - return AVERROR_INVALIDDATA; - - st = avformat_new_stream(s, NULL); - if (!st) - return AVERROR(ENOMEM); - - /* GIF format operates with time in "hundredths of second", - * therefore timebase is 1/100 */ - avpriv_set_pts_info(st, 64, 1, 100); - st->codec->codec_type = AVMEDIA_TYPE_VIDEO; - st->codec->codec_id = AV_CODEC_ID_GIF; - st->codec->width = width; - st->codec->height = height; - - /* jump to start because gif decoder needs header data too */ - if (avio_seek(pb, 0, SEEK_SET) != 0) - return AVERROR(EIO); - - return 0; -} - -static int gif_skip_subblocks(AVIOContext *pb) -{ - int sb_size, ret = 0; - - while (0x00 != (sb_size = avio_r8(pb))) { - if ((ret = avio_skip(pb, sb_size)) < 0) - return ret; - } - - return ret; -} - -static int gif_read_ext(AVFormatContext *s) -{ - GIFDemuxContext *gdc = s->priv_data; - AVIOContext *pb = s->pb; - int sb_size, ext_label = avio_r8(pb); - int ret; - - if (ext_label == GIF_GCE_EXT_LABEL) { - if ((sb_size = avio_r8(pb)) < 4) { - av_log(s, AV_LOG_FATAL, "Graphic Control Extension block's size less than 4.\n"); - return AVERROR_INVALIDDATA; - } - - /* skip packed fields */ - if ((ret = avio_skip(pb, 1)) < 0) - return ret; - - gdc->delay = avio_rl16(pb); - - if (gdc->delay < gdc->min_delay) - gdc->delay = gdc->default_delay; - - /* skip the rest of the Graphic Control Extension block */ - if ((ret = avio_skip(pb, sb_size - 3)) < 0 ) - return ret; - } else if (ext_label == GIF_APP_EXT_LABEL) { - uint8_t data[256]; - - sb_size = avio_r8(pb); - ret = avio_read(pb, data, sb_size); - if (ret < 0 || !sb_size) - return ret; - - if (sb_size == strlen(NETSCAPE_EXT_STR)) { - sb_size = avio_r8(pb); - ret = avio_read(pb, data, sb_size); - if (ret < 0 || !sb_size) - return ret; - - if (sb_size == 3 && data[0] == 1) { - gdc->total_iter = AV_RL16(data+1); - - if (gdc->total_iter == 0) - gdc->total_iter = -1; - } - } - } - - if ((ret = gif_skip_subblocks(pb)) < 0) - return ret; - - return 0; -} - -static int gif_read_packet(AVFormatContext *s, AVPacket *pkt) -{ - GIFDemuxContext *gdc = s->priv_data; - AVIOContext *pb = s->pb; - int packed_fields, block_label, ct_size, - keyframe, frame_parsed = 0, ret; - int64_t frame_start = avio_tell(pb), frame_end; - unsigned char buf[6]; - - if ((ret = avio_read(pb, buf, 6)) == 6) { - keyframe = memcmp(buf, gif87a_sig, 6) == 0 || - memcmp(buf, gif89a_sig, 6) == 0; - } else if (ret < 0) { - return ret; - } else { - keyframe = 0; - } - - if (keyframe) { -parse_keyframe: - /* skip 2 bytes of width and 2 of height */ - if ((ret = avio_skip(pb, 4)) < 0) - return ret; - - packed_fields = avio_r8(pb); - - /* skip 1 byte of Background Color Index and 1 byte of Pixel Aspect Ratio */ - if ((ret = avio_skip(pb, 2)) < 0) - return ret; - - /* global color table presence */ - if (packed_fields & 0x80) { - ct_size = 3 * (1 << ((packed_fields & 0x07) + 1)); - - if ((ret = avio_skip(pb, ct_size)) < 0) - return ret; - } - } else { - avio_seek(pb, -ret, SEEK_CUR); - ret = AVERROR_EOF; - } - - while (GIF_TRAILER != (block_label = avio_r8(pb)) && !url_feof(pb)) { - if (block_label == GIF_EXTENSION_INTRODUCER) { - if ((ret = gif_read_ext (s)) < 0 ) - goto resync; - } else if (block_label == GIF_IMAGE_SEPARATOR) { - /* skip to last byte of Image Descriptor header */ - if ((ret = avio_skip(pb, 8)) < 0) - return ret; - - packed_fields = avio_r8(pb); - - /* local color table presence */ - if (packed_fields & 0x80) { - ct_size = 3 * (1 << ((packed_fields & 0x07) + 1)); - - if ((ret = avio_skip(pb, ct_size)) < 0) - return ret; - } - - /* read LZW Minimum Code Size */ - if (avio_r8(pb) < 1) { - av_log(s, AV_LOG_ERROR, "lzw minimum code size must be >= 1\n"); - goto resync; - } - - if ((ret = gif_skip_subblocks(pb)) < 0) - goto resync; - - frame_end = avio_tell(pb); - - if (avio_seek(pb, frame_start, SEEK_SET) != frame_start) - return AVERROR(EIO); - - ret = av_get_packet(pb, pkt, frame_end - frame_start); - if (ret < 0) - return ret; - - if (keyframe) - pkt->flags |= AV_PKT_FLAG_KEY; - - pkt->stream_index = 0; - pkt->duration = gdc->delay; - - /* Graphic Control Extension's scope is single frame. - * Remove its influence. */ - gdc->delay = gdc->default_delay; - frame_parsed = 1; - - break; - } else { - av_log(s, AV_LOG_ERROR, "invalid block label\n"); -resync: - if (!keyframe) - avio_seek(pb, frame_start, SEEK_SET); - if ((ret = resync(pb)) < 0) - return ret; - frame_start = avio_tell(pb) - 6; - keyframe = 1; - goto parse_keyframe; - } - } - - if ((ret >= 0 && !frame_parsed) || ret == AVERROR_EOF) { - /* This might happen when there is no image block - * between extension blocks and GIF_TRAILER or EOF */ - if (!gdc->ignore_loop && (block_label == GIF_TRAILER || url_feof(pb)) - && (gdc->total_iter < 0 || ++gdc->iter_count < gdc->total_iter)) - return avio_seek(pb, 0, SEEK_SET); - return AVERROR_EOF; - } else - return ret; -} - -static const AVOption options[] = { - { "min_delay" , "minimum valid delay between frames (in hundredths of second)", offsetof(GIFDemuxContext, min_delay) , AV_OPT_TYPE_INT, {.i64 = GIF_MIN_DELAY} , 0, 100 * 60, AV_OPT_FLAG_DECODING_PARAM }, - { "default_delay", "default delay between frames (in hundredths of second)" , offsetof(GIFDemuxContext, default_delay), AV_OPT_TYPE_INT, {.i64 = GIF_DEFAULT_DELAY}, 0, 100 * 60, AV_OPT_FLAG_DECODING_PARAM }, - { "ignore_loop" , "ignore loop setting (netscape extension)" , offsetof(GIFDemuxContext, ignore_loop) , AV_OPT_TYPE_INT, {.i64 = 1} , 0, 1, AV_OPT_FLAG_DECODING_PARAM }, - { NULL }, -}; - -static const AVClass demuxer_class = { - .class_name = "GIF demuxer", - .item_name = av_default_item_name, - .option = options, - .version = LIBAVUTIL_VERSION_INT, - .category = AV_CLASS_CATEGORY_DEMUXER, -}; - -AVInputFormat ff_gif_demuxer = { - .name = "gif", - .long_name = NULL_IF_CONFIG_SMALL("CompuServe Graphics Interchange Format (GIF)"), - .priv_data_size = sizeof(GIFDemuxContext), - .read_probe = gif_probe, - .read_header = gif_read_header, - .read_packet = gif_read_packet, - .flags = AVFMT_GENERIC_INDEX, - .priv_class = &demuxer_class, -}; -- cgit v1.2.3