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
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 #include "demux.h"
32 #include "internal.h"
33
34 #define VC1_EXTRADATA_SIZE 4
35
vc1t_probe(const AVProbeData * p)36 static int vc1t_probe(const AVProbeData *p)
37 {
38 uint32_t size;
39
40 if (p->buf_size < 24)
41 return 0;
42
43 size = AV_RL32(&p->buf[4]);
44 if (p->buf[3] != 0xC5 || size < 4 || size > p->buf_size - 20 ||
45 AV_RL32(&p->buf[size+16]) != 0xC)
46 return 0;
47
48 return AVPROBE_SCORE_EXTENSION;
49 }
50
vc1t_read_header(AVFormatContext * s)51 static int vc1t_read_header(AVFormatContext *s)
52 {
53 AVIOContext *pb = s->pb;
54 AVStream *st;
55 int frames, ret;
56 uint32_t fps;
57 uint32_t size;
58
59 frames = avio_rl24(pb);
60 if (avio_r8(pb) != 0xC5 || ((size = avio_rl32(pb)) < 4))
61 return AVERROR_INVALIDDATA;
62
63 /* init video codec */
64 st = avformat_new_stream(s, NULL);
65 if (!st)
66 return AVERROR(ENOMEM);
67
68 st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
69 st->codecpar->codec_id = AV_CODEC_ID_WMV3;
70
71 if ((ret = ff_get_extradata(s, st->codecpar, pb, VC1_EXTRADATA_SIZE)) < 0)
72 return ret;
73
74 avio_skip(pb, size - 4);
75 st->codecpar->height = avio_rl32(pb);
76 st->codecpar->width = avio_rl32(pb);
77 if(avio_rl32(pb) != 0xC)
78 return AVERROR_INVALIDDATA;
79 avio_skip(pb, 8);
80 fps = avio_rl32(pb);
81 if(fps == 0xFFFFFFFF)
82 avpriv_set_pts_info(st, 32, 1, 1000);
83 else{
84 if (!fps) {
85 av_log(s, AV_LOG_ERROR, "Zero FPS specified, defaulting to 1 FPS\n");
86 fps = 1;
87 }
88 avpriv_set_pts_info(st, 24, 1, fps);
89 st->duration = frames;
90 }
91
92 return 0;
93 }
94
vc1t_read_packet(AVFormatContext * s,AVPacket * pkt)95 static int vc1t_read_packet(AVFormatContext *s,
96 AVPacket *pkt)
97 {
98 AVIOContext *pb = s->pb;
99 int frame_size;
100 int keyframe = 0;
101 uint32_t pts;
102
103 if(avio_feof(pb))
104 return AVERROR(EIO);
105
106 frame_size = avio_rl24(pb);
107 if(avio_r8(pb) & 0x80)
108 keyframe = 1;
109 pts = avio_rl32(pb);
110 if(av_get_packet(pb, pkt, frame_size) < 0)
111 return AVERROR(EIO);
112 if(s->streams[0]->time_base.den == 1000)
113 pkt->pts = pts;
114 pkt->flags |= keyframe ? AV_PKT_FLAG_KEY : 0;
115 pkt->pos -= 8;
116
117 return pkt->size;
118 }
119
120 const AVInputFormat ff_vc1t_demuxer = {
121 .name = "vc1test",
122 .long_name = NULL_IF_CONFIG_SMALL("VC-1 test bitstream"),
123 .read_probe = vc1t_probe,
124 .read_header = vc1t_read_header,
125 .read_packet = vc1t_read_packet,
126 .extensions = "rcv",
127 .flags = AVFMT_GENERIC_INDEX,
128 };
129