PeerStreamer

/*

 * 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"

#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,

                           AVFormatParameters *ap)

{

    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 = av_new_stream(s, 0);

    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_seek(pb, 8, SEEK_CUR);

    fps = avio_rl32(pb);

    if(fps == 0xFFFFFFFF)

        av_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;

        }

        av_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(pb->eof_reached)

        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 = {

    "vc1test",

    NULL_IF_CONFIG_SMALL("VC-1 test bitstream format"),

    0,

    vc1t_probe,

    vc1t_read_header,

    vc1t_read_packet,

    .flags = AVFMT_GENERIC_INDEX,

};