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/*
* VC1 Test Bitstreams Format Demuxer
* Copyright (c) 2006, 2008 Konstantin Shishkov
*
* 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
* VC1 test bitstream file demuxer
* by Konstantin Shishkov
* Format specified in SMPTE standard 421 Annex L
*/
#include "libavutil/intreadwrite.h"
#include "avformat.h"
#include "internal.h"
#define VC1_EXTRADATA_SIZE 4
static int vc1t_probe(AVProbeData *p)
{
if (p->buf_size < 24)
return 0;
if (p->buf[3] != 0xC5 || AV_RL32(&p->buf[4]) != 4 || AV_RL32(&p->buf[20]) != 0xC)
return 0;
return AVPROBE_SCORE_MAX/2;
}
static int vc1t_read_header(AVFormatContext *s)
{
AVIOContext *pb = s->pb;
AVStream *st;
int frames;
uint32_t fps;
frames = avio_rl24(pb);
if(avio_r8(pb) != 0xC5 || avio_rl32(pb) != 4)
return -1;
/* init video codec */
st = avformat_new_stream(s, NULL);
if (!st)
return -1;
st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
st->codec->codec_id = CODEC_ID_WMV3;
st->codec->extradata = av_malloc(VC1_EXTRADATA_SIZE);
st->codec->extradata_size = VC1_EXTRADATA_SIZE;
avio_read(pb, st->codec->extradata, VC1_EXTRADATA_SIZE);
st->codec->height = avio_rl32(pb);
st->codec->width = avio_rl32(pb);
if(avio_rl32(pb) != 0xC)
return -1;
avio_skip(pb, 8);
fps = avio_rl32(pb);
if(fps == 0xFFFFFFFF)
avpriv_set_pts_info(st, 32, 1, 1000);
else{
if (!fps) {
av_log(s, AV_LOG_ERROR, "Zero FPS specified, defaulting to 1 FPS\n");
fps = 1;
}
avpriv_set_pts_info(st, 24, 1, fps);
st->duration = frames;
}
return 0;
}
static int vc1t_read_packet(AVFormatContext *s,
AVPacket *pkt)
{
AVIOContext *pb = s->pb;
int frame_size;
int keyframe = 0;
uint32_t pts;
if(url_feof(pb))
return AVERROR(EIO);
frame_size = avio_rl24(pb);
if(avio_r8(pb) & 0x80)
keyframe = 1;
pts = avio_rl32(pb);
if(av_get_packet(pb, pkt, frame_size) < 0)
return AVERROR(EIO);
if(s->streams[0]->time_base.den == 1000)
pkt->pts = pts;
pkt->flags |= keyframe ? AV_PKT_FLAG_KEY : 0;
pkt->pos -= 8;
return pkt->size;
}
AVInputFormat ff_vc1t_demuxer = {
.name = "vc1test",
.long_name = NULL_IF_CONFIG_SMALL("VC-1 test bitstream format"),
.read_probe = vc1t_probe,
.read_header = vc1t_read_header,
.read_packet = vc1t_read_packet,
.flags = AVFMT_GENERIC_INDEX,
};