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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 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 "internal.h"
32 
33 #define VC1_EXTRADATA_SIZE 4
34 
35 static int vc1t_probe(AVProbeData *p)
36 {
37  uint32_t size;
38 
39  if (p->buf_size < 24)
40  return 0;
41 
42  size = AV_RL32(&p->buf[4]);
43  if (p->buf[3] != 0xC5 || size < 4 || size > p->buf_size - 20 ||
44  AV_RL32(&p->buf[size+16]) != 0xC)
45  return 0;
46 
48 }
49 
51 {
52  AVIOContext *pb = s->pb;
53  AVStream *st;
54  int frames;
55  uint32_t fps;
56  uint32_t size;
57 
58  frames = avio_rl24(pb);
59  if (avio_r8(pb) != 0xC5 || ((size = avio_rl32(pb)) < 4))
60  return AVERROR_INVALIDDATA;
61 
62  /* init video codec */
63  st = avformat_new_stream(s, NULL);
64  if (!st)
65  return AVERROR(ENOMEM);
66 
69 
70  if (ff_get_extradata(s, st->codecpar, pb, VC1_EXTRADATA_SIZE) < 0)
71  return AVERROR(ENOMEM);
72 
73  avio_skip(pb, size - 4);
74  st->codecpar->height = avio_rl32(pb);
75  st->codecpar->width = avio_rl32(pb);
76  if(avio_rl32(pb) != 0xC)
77  return AVERROR_INVALIDDATA;
78  avio_skip(pb, 8);
79  fps = avio_rl32(pb);
80  if(fps == 0xFFFFFFFF)
81  avpriv_set_pts_info(st, 32, 1, 1000);
82  else{
83  if (!fps) {
84  av_log(s, AV_LOG_ERROR, "Zero FPS specified, defaulting to 1 FPS\n");
85  fps = 1;
86  }
87  avpriv_set_pts_info(st, 24, 1, fps);
88  st->duration = frames;
89  }
90 
91  return 0;
92 }
93 
95  AVPacket *pkt)
96 {
97  AVIOContext *pb = s->pb;
98  int frame_size;
99  int keyframe = 0;
100  uint32_t pts;
101 
102  if(avio_feof(pb))
103  return AVERROR(EIO);
104 
105  frame_size = avio_rl24(pb);
106  if(avio_r8(pb) & 0x80)
107  keyframe = 1;
108  pts = avio_rl32(pb);
109  if(av_get_packet(pb, pkt, frame_size) < 0)
110  return AVERROR(EIO);
111  if(s->streams[0]->time_base.den == 1000)
112  pkt->pts = pts;
113  pkt->flags |= keyframe ? AV_PKT_FLAG_KEY : 0;
114  pkt->pos -= 8;
115 
116  return pkt->size;
117 }
118 
120  .name = "vc1test",
121  .long_name = NULL_IF_CONFIG_SMALL("VC-1 test bitstream"),
122  .read_probe = vc1t_probe,
123  .read_header = vc1t_read_header,
124  .read_packet = vc1t_read_packet,
125  .extensions = "rcv",
126  .flags = AVFMT_GENERIC_INDEX,
127 };
#define NULL
Definition: coverity.c:32
Bytestream IO Context.
Definition: avio.h:161
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
int64_t pos
byte position in stream, -1 if unknown
Definition: avcodec.h:1465
void avpriv_set_pts_info(AVStream *s, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: utils.c:4882
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3900
int size
Definition: avcodec.h:1446
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:331
static AVPacket pkt
Format I/O context.
Definition: avformat.h:1351
int width
Video only.
Definition: avcodec.h:3966
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4455
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1419
int av_get_packet(AVIOContext *s, AVPacket *pkt, int size)
Allocate and read the payload of a packet and initialize its fields with default values.
Definition: utils.c:310
ptrdiff_t size
Definition: opengl_enc.c:101
#define av_log(a,...)
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: avcodec.h:1477
static int vc1t_probe(AVProbeData *p)
Definition: vc1test.c:35
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:770
#define AVERROR(e)
Definition: error.h:43
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3896
int flags
A combination of AV_PKT_FLAG values.
Definition: avcodec.h:1451
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:639
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:451
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:450
AVInputFormat ff_vc1t_demuxer
Definition: vc1test.c:119
static int vc1t_read_header(AVFormatContext *s)
Definition: vc1test.c:50
#define s(width, name)
Definition: cbs_vp9.c:257
int frames
Definition: movenc.c:65
#define VC1_EXTRADATA_SIZE
Definition: vc1test.c:33
Stream structure.
Definition: avformat.h:874
int frame_size
Definition: mxfenc.c:2092
AVIOContext * pb
I/O context.
Definition: avformat.h:1393
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:470
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:458
This structure contains the data a format has to probe a file.
Definition: avformat.h:448
static int64_t pts
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:923
Main libavformat public API header.
int ff_get_extradata(AVFormatContext *s, AVCodecParameters *par, AVIOContext *pb, int size)
Allocate extradata with additional AV_INPUT_BUFFER_PADDING_SIZE at end which is always set to 0 and f...
Definition: utils.c:3305
int den
Denominator.
Definition: rational.h:60
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:647
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1021
int avio_feof(AVIOContext *s)
feof() equivalent for AVIOContext.
Definition: aviobuf.c:358
unsigned int avio_rl24(AVIOContext *s)
Definition: aviobuf.c:762
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented...
Definition: avformat.h:903
static int vc1t_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: vc1test.c:94
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:87
This structure stores compressed data.
Definition: avcodec.h:1422
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:1438