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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  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 
43 }
44 
46 {
47  AVIOContext *pb = s->pb;
48  AVStream *st;
49  int frames;
50  uint32_t fps;
51 
52  frames = avio_rl24(pb);
53  if(avio_r8(pb) != 0xC5 || avio_rl32(pb) != 4)
54  return AVERROR_INVALIDDATA;
55 
56  /* init video codec */
57  st = avformat_new_stream(s, NULL);
58  if (!st)
59  return AVERROR(ENOMEM);
60 
63 
64  if (ff_get_extradata(s, st->codecpar, pb, VC1_EXTRADATA_SIZE) < 0)
65  return AVERROR(ENOMEM);
66  st->codecpar->height = avio_rl32(pb);
67  st->codecpar->width = avio_rl32(pb);
68  if(avio_rl32(pb) != 0xC)
69  return AVERROR_INVALIDDATA;
70  avio_skip(pb, 8);
71  fps = avio_rl32(pb);
72  if(fps == 0xFFFFFFFF)
73  avpriv_set_pts_info(st, 32, 1, 1000);
74  else{
75  if (!fps) {
76  av_log(s, AV_LOG_ERROR, "Zero FPS specified, defaulting to 1 FPS\n");
77  fps = 1;
78  }
79  avpriv_set_pts_info(st, 24, 1, fps);
80  st->duration = frames;
81  }
82 
83  return 0;
84 }
85 
87  AVPacket *pkt)
88 {
89  AVIOContext *pb = s->pb;
90  int frame_size;
91  int keyframe = 0;
92  uint32_t pts;
93 
94  if(avio_feof(pb))
95  return AVERROR(EIO);
96 
97  frame_size = avio_rl24(pb);
98  if(avio_r8(pb) & 0x80)
99  keyframe = 1;
100  pts = avio_rl32(pb);
101  if(av_get_packet(pb, pkt, frame_size) < 0)
102  return AVERROR(EIO);
103  if(s->streams[0]->time_base.den == 1000)
104  pkt->pts = pts;
105  pkt->flags |= keyframe ? AV_PKT_FLAG_KEY : 0;
106  pkt->pos -= 8;
107 
108  return pkt->size;
109 }
110 
112  .name = "vc1test",
113  .long_name = NULL_IF_CONFIG_SMALL("VC-1 test bitstream"),
114  .read_probe = vc1t_probe,
115  .read_header = vc1t_read_header,
116  .read_packet = vc1t_read_packet,
117  .flags = AVFMT_GENERIC_INDEX,
118 };
#define NULL
Definition: coverity.c:32
const char * s
Definition: avisynth_c.h:768
Bytestream IO Context.
Definition: avio.h:147
#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:1620
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:4549
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3969
int size
Definition: avcodec.h:1601
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:304
static AVPacket pkt
Format I/O context.
Definition: avformat.h:1330
int width
Video only.
Definition: avcodec.h:4035
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4182
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1398
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:289
#define av_log(a,...)
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: avcodec.h:1632
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:726
#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:176
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3965
int flags
A combination of AV_PKT_FLAG values.
Definition: avcodec.h:1606
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:595
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:464
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:463
AVInputFormat ff_vc1t_demuxer
Definition: vc1test.c:111
static int vc1t_read_header(AVFormatContext *s)
Definition: vc1test.c:45
int frames
Definition: movenc.c:65
#define VC1_EXTRADATA_SIZE
Definition: vc1test.c:33
Stream structure.
Definition: avformat.h:881
int frame_size
Definition: mxfenc.c:1822
AVIOContext * pb
I/O context.
Definition: avformat.h:1372
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:487
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:471
This structure contains the data a format has to probe a file.
Definition: avformat.h:461
static int64_t pts
Global timestamp for the audio frames.
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:935
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:3186
int den
Denominator.
Definition: rational.h:60
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:662
AVCodecParameters * codecpar
Definition: avformat.h:1233
int avio_feof(AVIOContext *s)
feof() equivalent for AVIOContext.
Definition: aviobuf.c:328
unsigned int avio_rl24(AVIOContext *s)
Definition: aviobuf.c:718
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented...
Definition: avformat.h:918
static int vc1t_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: vc1test.c:86
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:87
This structure stores compressed data.
Definition: avcodec.h:1577
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:1593