Libav
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 
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 
65  if (!st->codec->extradata)
66  return AVERROR(ENOMEM);
69  st->codec->height = avio_rl32(pb);
70  st->codec->width = avio_rl32(pb);
71  if(avio_rl32(pb) != 0xC)
72  return AVERROR_INVALIDDATA;
73  avio_skip(pb, 8);
74  fps = avio_rl32(pb);
75  if(fps == 0xFFFFFFFF)
76  avpriv_set_pts_info(st, 32, 1, 1000);
77  else{
78  if (!fps) {
79  av_log(s, AV_LOG_ERROR, "Zero FPS specified, defaulting to 1 FPS\n");
80  fps = 1;
81  }
82  avpriv_set_pts_info(st, 24, 1, fps);
83  st->duration = frames;
84  }
85 
86  return 0;
87 }
88 
90  AVPacket *pkt)
91 {
92  AVIOContext *pb = s->pb;
93  int frame_size;
94  int keyframe = 0;
95  uint32_t pts;
96 
97  if(pb->eof_reached)
98  return AVERROR(EIO);
99 
100  frame_size = avio_rl24(pb);
101  if(avio_r8(pb) & 0x80)
102  keyframe = 1;
103  pts = avio_rl32(pb);
104  if(av_get_packet(pb, pkt, frame_size) < 0)
105  return AVERROR(EIO);
106  if(s->streams[0]->time_base.den == 1000)
107  pkt->pts = pts;
108  pkt->flags |= keyframe ? AV_PKT_FLAG_KEY : 0;
109  pkt->pos -= 8;
110 
111  return pkt->size;
112 }
113 
115  .name = "vc1test",
116  .long_name = NULL_IF_CONFIG_SMALL("VC-1 test bitstream"),
117  .read_probe = vc1t_probe,
118  .read_header = vc1t_read_header,
119  .read_packet = vc1t_read_packet,
120  .flags = AVFMT_GENERIC_INDEX,
121 };
void * av_malloc(size_t size)
Allocate a block of size bytes with alignment suitable for all memory accesses (including vectors if ...
Definition: mem.c:62
Bytestream IO Context.
Definition: avio.h:68
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:54
int64_t pos
byte position in stream, -1 if unknown
Definition: avcodec.h:998
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:2829
int size
Definition: avcodec.h:974
Format I/O context.
Definition: avformat.h:922
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1164
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:2521
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:990
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:117
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:452
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: avcodec.h:1019
static int vc1t_probe(AVProbeData *p)
Definition: vc1test.c:35
static const uint8_t frame_size[4]
Definition: g723_1_data.h:47
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:123
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:564
#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:145
void av_log(void *avcl, int level, const char *fmt,...)
Definition: log.c:169
int flags
A combination of AV_PKT_FLAG values.
Definition: avcodec.h:979
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:443
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:718
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:398
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:397
int width
picture width / height.
Definition: avcodec.h:1229
AVInputFormat ff_vc1t_demuxer
Definition: vc1test.c:114
static av_always_inline int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: avio.h:210
static int vc1t_read_header(AVFormatContext *s)
Definition: vc1test.c:45
#define AV_RL32
Definition: intreadwrite.h:146
#define VC1_EXTRADATA_SIZE
Definition: vc1test.c:33
Stream structure.
Definition: avformat.h:699
NULL
Definition: eval.c:55
enum AVMediaType codec_type
Definition: avcodec.h:1058
enum AVCodecID codec_id
Definition: avcodec.h:1067
AVIOContext * pb
I/O context.
Definition: avformat.h:964
int extradata_size
Definition: avcodec.h:1165
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:417
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:402
This structure contains the data a format has to probe a file.
Definition: avformat.h:395
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:756
Main libavformat public API header.
int den
denominator
Definition: rational.h:45
int eof_reached
true if eof reached
Definition: avio.h:96
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:525
unsigned int avio_rl24(AVIOContext *s)
Definition: aviobuf.c:556
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented...
Definition: avformat.h:741
static int vc1t_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: vc1test.c:89
This structure stores compressed data.
Definition: avcodec.h:950
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:966