vc1test.c
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1 /*
2  * VC1 Test Bitstreams Format Demuxer
3  * Copyright (c) 2006, 2008 Konstantin Shishkov
4  *
5  * This file is part of Libav.
6  *
7  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
29 #include "libavutil/intreadwrite.h"
30 #include "avformat.h"
31 #include "internal.h"
32 
33 #define VC1_EXTRADATA_SIZE 4
34 
35 static int vc1t_probe(AVProbeData *p)
36 {
37  if (p->buf_size < 24)
38  return 0;
39  if (p->buf[3] != 0xC5 || AV_RL32(&p->buf[4]) != 4 || AV_RL32(&p->buf[20]) != 0xC)
40  return 0;
41 
42  return AVPROBE_SCORE_MAX/2;
43 }
44 
47 {
48  AVIOContext *pb = s->pb;
49  AVStream *st;
50  int frames;
51  uint32_t fps;
52 
53  frames = avio_rl24(pb);
54  if(avio_r8(pb) != 0xC5 || avio_rl32(pb) != 4)
55  return -1;
56 
57  /* init video codec */
58  st = avformat_new_stream(s, NULL);
59  if (!st)
60  return -1;
61 
64 
68  st->codec->height = avio_rl32(pb);
69  st->codec->width = avio_rl32(pb);
70  if(avio_rl32(pb) != 0xC)
71  return -1;
72  avio_skip(pb, 8);
73  fps = avio_rl32(pb);
74  if(fps == 0xFFFFFFFF)
75  avpriv_set_pts_info(st, 32, 1, 1000);
76  else{
77  if (!fps) {
78  av_log(s, AV_LOG_ERROR, "Zero FPS specified, defaulting to 1 FPS\n");
79  fps = 1;
80  }
81  avpriv_set_pts_info(st, 24, 1, fps);
82  st->duration = frames;
83  }
84 
85  return 0;
86 }
87 
89  AVPacket *pkt)
90 {
91  AVIOContext *pb = s->pb;
92  int frame_size;
93  int keyframe = 0;
94  uint32_t pts;
95 
96  if(pb->eof_reached)
97  return AVERROR(EIO);
98 
99  frame_size = avio_rl24(pb);
100  if(avio_r8(pb) & 0x80)
101  keyframe = 1;
102  pts = avio_rl32(pb);
103  if(av_get_packet(pb, pkt, frame_size) < 0)
104  return AVERROR(EIO);
105  if(s->streams[0]->time_base.den == 1000)
106  pkt->pts = pts;
107  pkt->flags |= keyframe ? AV_PKT_FLAG_KEY : 0;
108  pkt->pos -= 8;
109 
110  return pkt->size;
111 }
112 
114  .name = "vc1test",
115  .long_name = NULL_IF_CONFIG_SMALL("VC-1 test bitstream format"),
116  .read_probe = vc1t_probe,
117  .read_header = vc1t_read_header,
118  .read_packet = vc1t_read_packet,
119  .flags = AVFMT_GENERIC_INDEX,
120 };