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  uint32_t data_offset;
48 
49  if (!st)
50  return AVERROR(ENOMEM);
51 
54 
55  avio_rl32(s->pb);
56  avio_rl32(s->pb);
57  st->codecpar->sample_rate = avio_rl32(s->pb);
58  st->codecpar->channels = avio_rl32(s->pb);
59  if (st->codecpar->channels > FF_SANE_NB_CHANNELS || st->codecpar->channels <= 0)
60  return AVERROR(ENOSYS);
61  ffformatcontext(s)->data_offset = data_offset = avio_rl32(s->pb);
62  avio_r8(s->pb);
63  st->codecpar->block_align = avio_rl32(s->pb);
64  if (st->codecpar->block_align > INT_MAX / FF_SANE_NB_CHANNELS || st->codecpar->block_align <= 0)
65  return AVERROR_INVALIDDATA;
67 
68  avio_seek(s->pb, data_offset, SEEK_SET);
69 
70  return 0;
71 }
72 
74 {
75  AVStream *st = s->streams[0];
76 
77  return av_get_packet(s->pb, pkt, st->codecpar->block_align);
78 }
79 
81  .name = "boa",
82  .long_name = NULL_IF_CONFIG_SMALL("Black Ops Audio"),
83  .read_probe = probe,
84  .read_header = read_header,
85  .read_packet = read_packet,
86  .flags = AVFMT_GENERIC_INDEX,
87 };
AV_CODEC_ID_ADPCM_MS
@ AV_CODEC_ID_ADPCM_MS
Definition: codec_id.h:359
AVERROR
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
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:760
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
probe
static int probe(const AVProbeData *p)
Definition: boadec.c:27
ffformatcontext
static av_always_inline FFFormatContext * ffformatcontext(AVFormatContext *s)
Definition: internal.h:191
read_packet
static int read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: boadec.c:73
internal.h
AVProbeData::buf_size
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:450
AVCodecParameters::channels
int channels
Audio only.
Definition: codec_par.h:166
AVFMT_GENERIC_INDEX
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:469
pkt
AVPacket * pkt
Definition: movenc.c:59
AVInputFormat
Definition: avformat.h:643
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:257
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:648
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:449
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
FFFormatContext::data_offset
int64_t data_offset
offset of the first packet
Definition: internal.h:99
AV_RL16
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_RL16
Definition: bytestream.h:94
AVFormatContext
Format I/O context.
Definition: avformat.h:1193
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1088
NULL
#define NULL
Definition: coverity.c:32
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:447
AVPROBE_SCORE_EXTENSION
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:457
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:170
ff_boa_demuxer
const AVInputFormat ff_boa_demuxer
Definition: boadec.c:80
avio_rl32
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:759
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
avio_r8
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:632
AVCodecParameters::block_align
int block_align
Audio only.
Definition: codec_par.h:177
av_get_packet
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:197
AVStream
Stream structure.
Definition: avformat.h:928
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:260
avformat.h
AV_RL32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:92
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
AVPacket
This structure stores compressed data.
Definition: packet.h:350
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
FF_SANE_NB_CHANNELS
#define FF_SANE_NB_CHANNELS
Definition: internal.h:101
read_header
static int read_header(AVFormatContext *s)
Definition: boadec.c:44