libavformat/vc1test.c

   1 /*
   2  * VC1 Test Bitstreams Format Demuxer
   3  * Copyright (c) 2006, 2008 Konstantin Shishkov
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * FFmpeg is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with FFmpeg; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 /**
  23  * @file libavformat/vc1test.c
  24  * VC1 test bitstream file demuxer
  25  * by Konstantin Shishkov
  26  * Format specified in SMPTE standard 421 Annex L
  27  */
  28
  29 #include "libavutil/intreadwrite.h"
  30 #include "avformat.h"
  31
  32 #define VC1_EXTRADATA_SIZE 4
  33
  34 static int vc1t_probe(AVProbeData *p)
  35 {
  36     if (p->buf[3] != 0xC5 && AV_RL32(&p->buf[4]) != 4)
  37         return 0;
  38
  39     return AVPROBE_SCORE_MAX/2;
  40 }
  41
  42 static int vc1t_read_header(AVFormatContext *s,
  43                            AVFormatParameters *ap)
  44 {
  45     ByteIOContext *pb = s->pb;
  46     AVStream *st;
  47     int fps, frames;
  48
  49     frames = get_le24(pb);
  50     if(get_byte(pb) != 0xC5 || get_le32(pb) != 4)
  51         return -1;
  52
  53     /* init video codec */
  54     st = av_new_stream(s, 0);
  55     if (!st)
  56         return -1;
  57
  58     st->codec->codec_type = CODEC_TYPE_VIDEO;
  59     st->codec->codec_id = CODEC_ID_WMV3;
  60
  61     st->codec->extradata = av_malloc(VC1_EXTRADATA_SIZE);
  62     st->codec->extradata_size = VC1_EXTRADATA_SIZE;
  63     get_buffer(pb, st->codec->extradata, VC1_EXTRADATA_SIZE);
  64     st->codec->height = get_le32(pb);
  65     st->codec->width = get_le32(pb);
  66     if(get_le32(pb) != 0xC)
  67         return -1;
  68     url_fskip(pb, 8);
  69     fps = get_le32(pb);
  70     if(fps == -1)
  71         av_set_pts_info(st, 32, 1, 1000);
  72     else{
  73         av_set_pts_info(st, 24, 1, fps);
  74         st->duration = frames;
  75     }
  76
  77     return 0;
  78 }
  79
  80 static int vc1t_read_packet(AVFormatContext *s,
  81                            AVPacket *pkt)
  82 {
  83     ByteIOContext *pb = s->pb;
  84     int frame_size;
  85     int keyframe = 0;
  86     uint32_t pts;
  87
  88     if(url_feof(pb))
  89         return AVERROR(EIO);
  90
  91     frame_size = get_le24(pb);
  92     if(get_byte(pb) & 0x80)
  93         keyframe = 1;
  94     pts = get_le32(pb);
  95     if(av_get_packet(pb, pkt, frame_size) < 0)
  96         return AVERROR(EIO);
  97     if(s->streams[0]->time_base.den == 1000)
  98         pkt->pts = pts;
  99     pkt->flags |= keyframe ? PKT_FLAG_KEY : 0;
 100     pkt->pos -= 8;
 101
 102     return pkt->size;
 103 }
 104
 105 AVInputFormat vc1t_demuxer = {
 106     "vc1test",
 107     NULL_IF_CONFIG_SMALL("VC-1 test bitstream format"),
 108     0,
 109     vc1t_probe,
 110     vc1t_read_header,
 111     vc1t_read_packet,
 112     .flags = AVFMT_GENERIC_INDEX,
 113 };