FFmpeg
pcmdec.c
Go to the documentation of this file.
1 /*
2  * RAW PCM demuxers
3  * Copyright (c) 2002 Fabrice Bellard
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/avstring.h"
23 #include "avformat.h"
24 #include "internal.h"
25 #include "pcm.h"
26 #include "libavutil/log.h"
27 #include "libavutil/opt.h"
28 #include "libavutil/avassert.h"
29 
30 typedef struct PCMAudioDemuxerContext {
31  AVClass *class;
32  int sample_rate;
33  int channels;
34 } PCMAudioDemuxerContext;
35 
36 static int pcm_read_header(AVFormatContext *s)
37 {
38  PCMAudioDemuxerContext *s1 = s->priv_data;
39  AVCodecParameters *par;
40  AVStream *st;
41  uint8_t *mime_type = NULL;
42 
43  st = avformat_new_stream(s, NULL);
44  if (!st)
45  return AVERROR(ENOMEM);
46  par = st->codecpar;
47 
48  par->codec_type = AVMEDIA_TYPE_AUDIO;
49  par->codec_id = s->iformat->raw_codec_id;
50  par->sample_rate = s1->sample_rate;
51  par->channels = s1->channels;
52 
53  av_opt_get(s->pb, "mime_type", AV_OPT_SEARCH_CHILDREN, &mime_type);
54  if (mime_type && s->iformat->mime_type) {
55  int rate = 0, channels = 0, little_endian = 0;
56  const char *options;
57  if (av_stristart(mime_type, s->iformat->mime_type, &options)) { /* audio/L16 */
58  while (options = strchr(options, ';')) {
59  options++;
60  if (!rate)
61  sscanf(options, " rate=%d", &rate);
62  if (!channels)
63  sscanf(options, " channels=%d", &channels);
64  if (!little_endian) {
65  char val[sizeof("little-endian")];
66  if (sscanf(options, " endianness=%13s", val) == 1) {
67  little_endian = strcmp(val, "little-endian") == 0;
68  }
69  }
70  }
71  if (rate <= 0) {
72  av_log(s, AV_LOG_ERROR,
73  "Invalid sample_rate found in mime_type \"%s\"\n",
74  mime_type);
75  av_freep(&mime_type);
76  return AVERROR_INVALIDDATA;
77  }
78  par->sample_rate = rate;
79  if (channels > 0)
80  par->channels = channels;
81  if (little_endian)
82  par->codec_id = AV_CODEC_ID_PCM_S16LE;
83  }
84  }
85  av_freep(&mime_type);
86 
87  par->bits_per_coded_sample = av_get_bits_per_sample(par->codec_id);
88 
89  av_assert0(par->bits_per_coded_sample > 0);
90 
91  par->block_align = par->bits_per_coded_sample * par->channels / 8;
92 
93  avpriv_set_pts_info(st, 64, 1, par->sample_rate);
94  return 0;
95 }
96 
97 static const AVOption pcm_options[] = {
98  { "sample_rate", "", offsetof(PCMAudioDemuxerContext, sample_rate), AV_OPT_TYPE_INT, {.i64 = 44100}, 0, INT_MAX, AV_OPT_FLAG_DECODING_PARAM },
99  { "channels", "", offsetof(PCMAudioDemuxerContext, channels), AV_OPT_TYPE_INT, {.i64 = 1}, 0, INT_MAX, AV_OPT_FLAG_DECODING_PARAM },
100  { NULL },
101 };
102 static const AVClass pcm_demuxer_class = {
103  .class_name = "pcm demuxer",
104  .item_name = av_default_item_name,
105  .option = pcm_options,
106  .version = LIBAVUTIL_VERSION_INT,
107 };
108 
109 #define PCMDEF_0(name_, long_name_, ext, codec, ...)
110 #define PCMDEF_1(name_, long_name_, ext, codec, ...) \
111 const AVInputFormat ff_pcm_ ## name_ ## _demuxer = { \
112  .name = #name_, \
113  .long_name = NULL_IF_CONFIG_SMALL(long_name_), \
114  .priv_data_size = sizeof(PCMAudioDemuxerContext), \
115  .read_header = pcm_read_header, \
116  .read_packet = ff_pcm_read_packet, \
117  .read_seek = ff_pcm_read_seek, \
118  .flags = AVFMT_GENERIC_INDEX, \
119  .extensions = ext, \
120  .raw_codec_id = codec, \
121  .priv_class = &pcm_demuxer_class, \
122  __VA_ARGS__ \
123 };
124 #define PCMDEF_2(name, long_name, ext, codec, enabled, ...) \
125  PCMDEF_ ## enabled(name, long_name, ext, codec, __VA_ARGS__)
126 #define PCMDEF_3(name, long_name, ext, codec, config, ...) \
127  PCMDEF_2(name, long_name, ext, codec, config, __VA_ARGS__)
128 #define PCMDEF_EXT(name, long_name, ext, uppercase, ...) \
129  PCMDEF_3(name, long_name, ext, AV_CODEC_ID_PCM_ ## uppercase, \
130  CONFIG_PCM_ ## uppercase ## _DEMUXER, __VA_ARGS__)
131 #define PCMDEF(name, long_name, ext, uppercase) \
132  PCMDEF_EXT(name, long_name, ext, uppercase, )
133 
134 PCMDEF(f64be, "PCM 64-bit floating-point big-endian", NULL, F64BE)
135 PCMDEF(f64le, "PCM 64-bit floating-point little-endian", NULL, F64LE)
136 PCMDEF(f32be, "PCM 32-bit floating-point big-endian", NULL, F32BE)
137 PCMDEF(f32le, "PCM 32-bit floating-point little-endian", NULL, F32LE)
138 PCMDEF(s32be, "PCM signed 32-bit big-endian", NULL, S32BE)
139 PCMDEF(s32le, "PCM signed 32-bit little-endian", NULL, S32LE)
140 PCMDEF(s24be, "PCM signed 24-bit big-endian", NULL, S24BE)
141 PCMDEF(s24le, "PCM signed 24-bit little-endian", NULL, S24LE)
142 PCMDEF_EXT(s16be, "PCM signed 16-bit big-endian",
143  AV_NE("sw", NULL), S16BE, .mime_type = "audio/L16")
144 PCMDEF(s16le, "PCM signed 16-bit little-endian", AV_NE(NULL, "sw"), S16LE)
145 PCMDEF(s8, "PCM signed 8-bit", "sb", S8)
146 PCMDEF(u32be, "PCM unsigned 32-bit big-endian", NULL, U32BE)
147 PCMDEF(u32le, "PCM unsigned 32-bit little-endian", NULL, U32LE)
148 PCMDEF(u24be, "PCM unsigned 24-bit big-endian", NULL, U24BE)
149 PCMDEF(u24le, "PCM unsigned 24-bit little-endian", NULL, U24LE)
150 PCMDEF(u16be, "PCM unsigned 16-bit big-endian", AV_NE("uw", NULL), U16BE)
151 PCMDEF(u16le, "PCM unsigned 16-bit little-endian", AV_NE(NULL, "uw"), U16LE)
152 PCMDEF(u8, "PCM unsigned 8-bit", "ub", U8)
153 PCMDEF(alaw, "PCM A-law", "al", ALAW)
154 PCMDEF(mulaw, "PCM mu-law", "ul", MULAW)
155 PCMDEF(vidc, "PCM Archimedes VIDC", NULL, VIDC)
156 
157 #if CONFIG_SLN_DEMUXER
158 static const AVOption sln_options[] = {
159  { "sample_rate", "", offsetof(PCMAudioDemuxerContext, sample_rate), AV_OPT_TYPE_INT, {.i64 = 8000}, 0, INT_MAX, AV_OPT_FLAG_DECODING_PARAM },
160  { "channels", "", offsetof(PCMAudioDemuxerContext, channels), AV_OPT_TYPE_INT, {.i64 = 1}, 0, INT_MAX, AV_OPT_FLAG_DECODING_PARAM },
161  { NULL },
162 };
163 
164 static const AVClass sln_demuxer_class = {
165  .class_name = "sln demuxer",
166  .item_name = av_default_item_name,
167  .option = sln_options,
168  .version = LIBAVUTIL_VERSION_INT,
169 };
170 
171 const AVInputFormat ff_sln_demuxer = {
172  .name = "sln",
173  .long_name = NULL_IF_CONFIG_SMALL("Asterisk raw pcm"),
174  .priv_data_size = sizeof(PCMAudioDemuxerContext),
175  .read_header = pcm_read_header,
176  .read_packet = ff_pcm_read_packet,
177  .read_seek = ff_pcm_read_seek,
178  .flags = AVFMT_GENERIC_INDEX,
179  .extensions = "sln",
180  .raw_codec_id = AV_CODEC_ID_PCM_S16LE,
181  .priv_class = &sln_demuxer_class,
182 };
183 #endif
AV_CODEC_ID_PCM_S16LE
@ AV_CODEC_ID_PCM_S16LE
Definition: codec_id.h:314
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
opt.h
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:768
pcm.h
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
AVCodecParameters
This struct describes the properties of an encoded stream.
Definition: codec_par.h:52
PCMDEF
#define PCMDEF(name, long_name, ext, uppercase)
Definition: pcmdec.c:131
AVOption
AVOption.
Definition: opt.h:247
sample_rate
sample_rate
Definition: ffmpeg_filter.c:153
bit
#define bit(string, value)
Definition: cbs_mpeg2.c:58
A
#define A(x)
Definition: vp56_arith.h:28
AVCodecParameters::channels
int channels
Audio only.
Definition: codec_par.h:166
read_seek
static int read_seek(AVFormatContext *ctx, int stream_index, int64_t timestamp, int flags)
Definition: libcdio.c:149
PCMDEF_EXT
#define PCMDEF_EXT(name, long_name, ext, uppercase,...)
Definition: pcmdec.c:128
ub
#define ub(width, name)
Definition: cbs_h2645.c:266
AVFMT_GENERIC_INDEX
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:476
val
static double val(void *priv, double ch)
Definition: aeval.c:76
av_get_bits_per_sample
int av_get_bits_per_sample(enum AVCodecID codec_id)
Return codec bits per sample.
Definition: utils.c:580
avassert.h
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
AVInputFormat
Definition: avformat.h:650
pcm_options
static const AVOption pcm_options[]
Definition: pcmdec.c:97
s
#define s(width, name)
Definition: cbs_vp9.c:257
AV_NE
#define AV_NE(be, le)
Definition: macros.h:33
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:655
pcm_demuxer_class
static const AVClass pcm_demuxer_class
Definition: pcmdec.c:102
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
s1
#define s1
Definition: regdef.h:38
PCM
#define PCM(format)
Definition: avisynth.c:49
av_assert0
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:37
channels
channels
Definition: aptx.h:33
av_stristart
int av_stristart(const char *str, const char *pfx, const char **ptr)
Return non-zero if pfx is a prefix of str independent of case.
Definition: avstring.c:45
AVFormatContext
Format I/O context.
Definition: avformat.h:1200
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1095
LIBAVUTIL_VERSION_INT
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:527
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
NULL
#define NULL
Definition: coverity.c:32
ff_sln_demuxer
const AVInputFormat ff_sln_demuxer
av_default_item_name
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:235
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:170
options
const OptionDef options[]
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
AV_OPT_SEARCH_CHILDREN
#define AV_OPT_SEARCH_CHILDREN
Search in possible children of the given object first.
Definition: opt.h:559
PCMAudioDemuxerContext::sample_rate
int sample_rate
Definition: pcmdec.c:32
log.h
AVCodecParameters::block_align
int block_align
Audio only.
Definition: codec_par.h:177
AV_OPT_FLAG_DECODING_PARAM
#define AV_OPT_FLAG_DECODING_PARAM
a generic parameter which can be set by the user for demuxing or decoding
Definition: opt.h:278
ff_pcm_read_packet
int ff_pcm_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: pcm.c:29
read_packet
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
AVStream
Stream structure.
Definition: avformat.h:935
AVClass::class_name
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
Definition: log.h:71
ff_pcm_read_seek
int ff_pcm_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
Definition: pcm.c:56
avformat.h
AV_OPT_TYPE_INT
@ AV_OPT_TYPE_INT
Definition: opt.h:224
avpriv_set_pts_info
void avpriv_set_pts_info(AVStream *st, 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:1196
PCMAudioDemuxerContext
Definition: pcmdec.c:30
AVCodecParameters::bits_per_coded_sample
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: codec_par.h:102
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:35
pcm_read_header
static int pcm_read_header(AVFormatContext *s)
Definition: pcmdec.c:36
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561
S8
static const uint32_t S8[256]
Definition: cast5.c:324
av_opt_get
int av_opt_get(void *obj, const char *name, int search_flags, uint8_t **out_val)
Definition: opt.c:782
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
avstring.h
PCMAudioDemuxerContext::channels
int channels
Definition: pcmdec.c:33
Generated on Wed Aug 24 2022 21:38:26 for FFmpeg by   doxygen 1.8.17