FFmpeg  2.1.1
boadec.c
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1 /*
2  * Black ops audio demuxer
3  * Copyright (c) 2013 Michael Niedermayer
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 #include "libavutil/intreadwrite.h"
23 #include "avformat.h"
24 
25 static int probe(AVProbeData *p)
26 {
27  if (p->buf_size < 2096)
28  return 0;
29  if ( AV_RL32(p->buf ) != 1
30  || AV_RL32(p->buf + 8) > 100000
31  || AV_RL32(p->buf + 12) > 8
32  || AV_RL32(p->buf + 16) != 2096
33  ||!AV_RL32(p->buf + 21)
34  || AV_RL16(p->buf + 25) != 2096
35  || AV_RL32(p->buf + 48) % AV_RL32(p->buf + 21)
36  )
37  return 0;
39 }
40 
41 
43 {
44  AVStream *st = avformat_new_stream(s, NULL);
45  if (!st)
46  return AVERROR(ENOMEM);
47 
50 
51  avio_rl32(s->pb);
52  avio_rl32(s->pb);
53  st->codec->sample_rate = avio_rl32(s->pb);
54  st->codec->channels = avio_rl32(s->pb);
55  s->data_offset = avio_rl32(s->pb);
56  avio_r8(s->pb);
57  st->codec->block_align = st->codec->channels * avio_rl32(s->pb);
58 
59  avio_seek(s->pb, s->data_offset, SEEK_SET);
60 
61  return 0;
62 }
63 
65 {
66  AVStream *st = s->streams[0];
67 
68  return av_get_packet(s->pb, pkt, st->codec->block_align);
69 }
70 
72  .name = "boa",
73  .long_name = NULL_IF_CONFIG_SMALL("Black Ops Audio"),
74  .read_probe = probe,
75  .read_header = read_header,
76  .read_packet = read_packet,
77  .flags = AVFMT_GENERIC_INDEX,
78 };
const char * s
Definition: avisynth_c.h:668
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:478
#define AV_RL16(x)
Definition: intreadwrite.h:245
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:686
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:593
int64_t data_offset
offset of the first packet
Definition: avformat.h:1287
int block_align
number of bytes per packet if constant and known or 0 Used by some WAV based audio codecs...
Definition: avcodec.h:1910
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:471
Format I/O context.
Definition: avformat.h:968
static int read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: boadec.c:64
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:336
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:3348
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:200
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:151
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:355
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:337
AVStream ** streams
Definition: avformat.h:1016
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:341
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:199
AVInputFormat ff_boa_demuxer
Definition: boadec.c:71
Stream structure.
Definition: avformat.h:667
enum AVMediaType codec_type
Definition: avcodec.h:1154
enum AVCodecID codec_id
Definition: avcodec.h:1157
int sample_rate
samples per second
Definition: avcodec.h:1873
AVIOContext * pb
I/O context.
Definition: avformat.h:1001
static int read_header(AVFormatContext *s)
Definition: boadec.c:42
This structure contains the data a format has to probe a file.
Definition: avformat.h:334
Main libavformat public API header.
#define AV_RL32(x)
Definition: intreadwrite.h:275
int channels
number of audio channels
Definition: avcodec.h:1874
#define AVERROR(e)
static AVPacket pkt
Definition: demuxing.c:52
This structure stores compressed data.
Definition: avcodec.h:1040
static int probe(AVProbeData *p)
Definition: boadec.c:25