FFmpeg
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 "libavcodec/internal.h"
24 #include "avformat.h"
25 #include "internal.h"
26 
27 static int probe(const AVProbeData *p)
28 {
29  if (p->buf_size < 2096)
30  return 0;
31  if ( AV_RL32(p->buf ) != 1
32  || AV_RL32(p->buf + 8) > 100000
33  || AV_RL32(p->buf + 12) > 8
34  || AV_RL32(p->buf + 16) != 2096
35  ||!AV_RL32(p->buf + 21)
36  || AV_RL16(p->buf + 25) != 2096
37  || AV_RL32(p->buf + 48) % AV_RL32(p->buf + 21)
38  )
39  return 0;
41 }
42 
43 
45 {
47  if (!st)
48  return AVERROR(ENOMEM);
49 
52 
53  avio_rl32(s->pb);
54  avio_rl32(s->pb);
55  st->codecpar->sample_rate = avio_rl32(s->pb);
56  st->codecpar->channels = avio_rl32(s->pb);
57  if (st->codecpar->channels > FF_SANE_NB_CHANNELS || st->codecpar->channels <= 0)
58  return AVERROR(ENOSYS);
59  s->internal->data_offset = avio_rl32(s->pb);
60  avio_r8(s->pb);
61  st->codecpar->block_align = avio_rl32(s->pb);
62  if (st->codecpar->block_align > INT_MAX / FF_SANE_NB_CHANNELS || st->codecpar->block_align <= 0)
63  return AVERROR_INVALIDDATA;
65 
66  avio_seek(s->pb, s->internal->data_offset, SEEK_SET);
67 
68  return 0;
69 }
70 
72 {
73  AVStream *st = s->streams[0];
74 
75  return av_get_packet(s->pb, pkt, st->codecpar->block_align);
76 }
77 
79  .name = "boa",
80  .long_name = NULL_IF_CONFIG_SMALL("Black Ops Audio"),
81  .read_probe = probe,
82  .read_header = read_header,
83  .read_packet = read_packet,
84  .flags = AVFMT_GENERIC_INDEX,
85 };
#define FF_SANE_NB_CHANNELS
Definition: internal.h:97
#define NULL
Definition: coverity.c:32
static int probe(const AVProbeData *p)
Definition: boadec.c:27
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
int64_t data_offset
offset of the first packet
Definition: internal.h:80
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:253
AVFormatInternal * internal
An opaque field for libavformat internal usage.
Definition: avformat.h:1808
static AVPacket pkt
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_RL16
Definition: bytestream.h:91
Format I/O context.
Definition: avformat.h:1355
static int read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: boadec.c:71
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4449
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1423
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:305
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:752
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:153
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:628
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:444
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:443
int block_align
Audio only.
Definition: codec_par.h:177
#define s(width, name)
Definition: cbs_vp9.c:257
AVInputFormat ff_boa_demuxer
Definition: boadec.c:78
Stream structure.
Definition: avformat.h:880
AVIOContext * pb
I/O context.
Definition: avformat.h:1397
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:463
static int read_header(AVFormatContext *s)
Definition: boadec.c:44
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:451
This structure contains the data a format has to probe a file.
Definition: avformat.h:441
int sample_rate
Audio only.
Definition: codec_par.h:170
Main libavformat public API header.
common internal api header.
int channels
Audio only.
Definition: codec_par.h:166
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:652
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1027
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:91
This structure stores compressed data.
Definition: packet.h:340