FFmpeg: libavformat/pcmdec.c Source File

FFmpeg
pcmdec.c
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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 "config_components.h"
23 
24 #include "libavutil/avstring.h"
25 #include "libavutil/channel_layout.h"
26 #include "libavutil/mem.h"
27 #include "avformat.h"
28 #include "demux.h"
29 #include "internal.h"
30 #include "pcm.h"
31 #include "libavutil/log.h"
32 #include "libavutil/opt.h"
33 #include "libavutil/avassert.h"
34 
35  typedef struct PCMAudioDemuxerContext {
36   AVClass *class;
37   int sample_rate;
38   AVChannelLayout ch_layout;
39 } PCMAudioDemuxerContext;
40 
41  static int pcm_read_header(AVFormatContext *s)
42 {
43  PCMAudioDemuxerContext *s1 = s->priv_data;
44  AVCodecParameters *par;
45  AVStream *st;
46  uint8_t *mime_type = NULL;
47  int ret;
48 
49  st = avformat_new_stream(s, NULL);
50  if (!st)
51  return AVERROR(ENOMEM);
52  par = st->codecpar;
53 
54  par->codec_type = AVMEDIA_TYPE_AUDIO;
55  par->codec_id = ffifmt(s->iformat)->raw_codec_id;
56  par->sample_rate = s1->sample_rate;
57  ret = av_channel_layout_copy(&par->ch_layout, &s1->ch_layout);
58  if (ret < 0)
59  return ret;
60 
61  av_opt_get(s->pb, "mime_type", AV_OPT_SEARCH_CHILDREN, &mime_type);
62  if (mime_type && s->iformat->mime_type) {
63  int rate = 0, channels = 0, little_endian = 0;
64  const char *options;
65  if (av_stristart(mime_type, s->iformat->mime_type, &options)) { /* audio/L16 */
66  while (options = strchr(options, ';')) {
67  options++;
68  if (!rate)
69  sscanf(options, " rate=%d", &rate);
70  if (!channels)
71  sscanf(options, " channels=%d", &channels);
72  if (!little_endian) {
73  char val[sizeof("little-endian")];
74  if (sscanf(options, " endianness=%13s", val) == 1) {
75  little_endian = strcmp(val, "little-endian") == 0;
76  }
77  }
78  }
79  if (rate <= 0) {
80  av_log(s, AV_LOG_ERROR,
81  "Invalid sample_rate found in mime_type \"%s\"\n",
82  mime_type);
83  av_freep(&mime_type);
84  return AVERROR_INVALIDDATA;
85  }
86  par->sample_rate = rate;
87  if (channels > 0) {
88  av_channel_layout_uninit(&par->ch_layout);
89  par->ch_layout.nb_channels = channels;
90  }
91  if (little_endian)
92  par->codec_id = AV_CODEC_ID_PCM_S16LE;
93  }
94  }
95  av_freep(&mime_type);
96 
97  par->bits_per_coded_sample = av_get_bits_per_sample(par->codec_id);
98 
99  av_assert0(par->bits_per_coded_sample > 0);
100 
101  par->block_align = par->bits_per_coded_sample * par->ch_layout.nb_channels / 8;
102 
103  avpriv_set_pts_info(st, 64, 1, par->sample_rate);
104  return 0;
105 }
106 
107  static const AVOption pcm_options[] = {
108  { "sample_rate", "", offsetof(PCMAudioDemuxerContext, sample_rate), AV_OPT_TYPE_INT, {.i64 = 44100}, 0, INT_MAX, AV_OPT_FLAG_DECODING_PARAM },
109  { "ch_layout", "", offsetof(PCMAudioDemuxerContext, ch_layout), AV_OPT_TYPE_CHLAYOUT, {.str = "mono"}, 0, 0, AV_OPT_FLAG_DECODING_PARAM },
110  { NULL },
111 };
112  static const AVClass pcm_demuxer_class = {
113  .class_name = "pcm demuxer",
114  .item_name = av_default_item_name,
115  .option = pcm_options,
116  .version = LIBAVUTIL_VERSION_INT,
117 };
118 
119  #define PCMDEF_0(name_, long_name_, ext, codec, ...)
120  #define PCMDEF_1(name_, long_name_, ext, codec, ...) \
121 const FFInputFormat ff_pcm_ ## name_ ## _demuxer = { \
122  .p.name = #name_, \
123  .p.long_name = NULL_IF_CONFIG_SMALL(long_name_), \
124  .p.flags = AVFMT_GENERIC_INDEX, \
125  .p.extensions = ext, \
126  .p.priv_class = &pcm_demuxer_class, \
127  .priv_data_size = sizeof(PCMAudioDemuxerContext), \
128  .read_header = pcm_read_header, \
129  .read_packet = ff_pcm_read_packet, \
130  .read_seek = ff_pcm_read_seek, \
131  .raw_codec_id = codec, \
132  __VA_ARGS__ \
133 };
134  #define PCMDEF_2(name, long_name, ext, codec, enabled, ...) \
135  PCMDEF_ ## enabled(name, long_name, ext, codec, __VA_ARGS__)
136  #define PCMDEF_3(name, long_name, ext, codec, config, ...) \
137  PCMDEF_2(name, long_name, ext, codec, config, __VA_ARGS__)
138  #define PCMDEF_EXT(name, long_name, ext, uppercase, ...) \
139  PCMDEF_3(name, long_name, ext, AV_CODEC_ID_PCM_ ## uppercase, \
140  CONFIG_PCM_ ## uppercase ## _DEMUXER, __VA_ARGS__)
141  #define PCMDEF(name, long_name, ext, uppercase) \
142  PCMDEF_EXT(name, long_name, ext, uppercase, )
143 
144 PCMDEF(f64be, "PCM 64-bit floating-point big-endian", NULL, F64BE)
145 PCMDEF(f64le, "PCM 64-bit floating-point little-endian", NULL, F64LE)
146 PCMDEF(f32be, "PCM 32-bit floating-point big-endian", NULL, F32BE)
147 PCMDEF(f32le, "PCM 32-bit floating-point little-endian", NULL, F32LE)
148 PCMDEF(s32be, "PCM signed 32-bit big-endian", NULL, S32BE)
149 PCMDEF(s32le, "PCM signed 32-bit little-endian", NULL, S32LE)
150 PCMDEF(s24be, "PCM signed 24-bit big-endian", NULL, S24BE)
151 PCMDEF(s24le, "PCM signed 24-bit little-endian", NULL, S24LE)
152 PCMDEF_EXT(s16be, "PCM signed 16-bit big-endian",
153  AV_NE("sw", NULL), S16BE, .p.mime_type = "audio/L16")
154 PCMDEF(s16le, "PCM signed 16-bit little-endian", AV_NE(NULL, "sw"), S16LE)
155 PCMDEF(s8, "PCM signed 8-bit", "sb", S8)
156 PCMDEF(u32be, "PCM unsigned 32-bit big-endian", NULL, U32BE)
157 PCMDEF(u32le, "PCM unsigned 32-bit little-endian", NULL, U32LE)
158 PCMDEF(u24be, "PCM unsigned 24-bit big-endian", NULL, U24BE)
159 PCMDEF(u24le, "PCM unsigned 24-bit little-endian", NULL, U24LE)
160 PCMDEF(u16be, "PCM unsigned 16-bit big-endian", AV_NE("uw", NULL), U16BE)
161 PCMDEF(u16le, "PCM unsigned 16-bit little-endian", AV_NE(NULL, "uw"), U16LE)
162 PCMDEF(u8, "PCM unsigned 8-bit", "ub", U8)
163 PCMDEF(alaw, "PCM A-law", "al", ALAW)
164 PCMDEF(mulaw, "PCM mu-law", "ul", MULAW)
165 PCMDEF(vidc, "PCM Archimedes VIDC", NULL, VIDC)
166 
167 #if CONFIG_SLN_DEMUXER
168 static const AVOption sln_options[] = {
169  { "sample_rate", "", offsetof(PCMAudioDemuxerContext, sample_rate), AV_OPT_TYPE_INT, {.i64 = 8000}, 0, INT_MAX, AV_OPT_FLAG_DECODING_PARAM },
170  { "ch_layout", "", offsetof(PCMAudioDemuxerContext, ch_layout), AV_OPT_TYPE_CHLAYOUT, {.str = "mono"}, 0, 0, AV_OPT_FLAG_DECODING_PARAM },
171  { NULL },
172 };
173 
174 static const AVClass sln_demuxer_class = {
175  .class_name = "sln demuxer",
176  .item_name = av_default_item_name,
177  .option = sln_options,
178  .version = LIBAVUTIL_VERSION_INT,
179 };
180 
181 const FFInputFormat ff_sln_demuxer = {
182  .p.name = "sln",
183  .p.long_name = NULL_IF_CONFIG_SMALL("Asterisk raw pcm"),
184  .p.flags = AVFMT_GENERIC_INDEX,
185  .p.extensions = "sln",
186  .p.priv_class = &sln_demuxer_class,
187  .priv_data_size = sizeof(PCMAudioDemuxerContext),
188  .read_header = pcm_read_header,
189  .read_packet = ff_pcm_read_packet,
190  .read_seek = ff_pcm_read_seek,
191  .raw_codec_id = AV_CODEC_ID_PCM_S16LE,
192 };
193 #endif
AV_OPT_SEARCH_CHILDREN
#define AV_OPT_SEARCH_CHILDREN
Search in possible children of the given object first.
Definition: opt.h:605
AV_CODEC_ID_PCM_S16LE
@ AV_CODEC_ID_PCM_S16LE
Definition: codec_id.h:328
A
#define A(x)
Definition: vpx_arith.h:28
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
pcm.h
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:51
AVCodecParameters
This struct describes the properties of an encoded stream.
Definition: codec_par.h:47
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const struct AVCodec *c)
Add a new stream to a media file.
PCMDEF
#define PCMDEF(name, long_name, ext, uppercase)
Definition: pcmdec.c:141
AVOption
AVOption.
Definition: opt.h:429
AVChannelLayout::nb_channels
int nb_channels
Number of channels in this layout.
Definition: channel_layout.h:321
bit
#define bit(string, value)
Definition: cbs_mpeg2.c:56
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: avformat.c:860
read_seek
static int read_seek(AVFormatContext *ctx, int stream_index, int64_t timestamp, int flags)
Definition: libcdio.c:151
PCMDEF_EXT
#define PCMDEF_EXT(name, long_name, ext, uppercase,...)
Definition: pcmdec.c:138
ub
#define ub(width, name)
Definition: cbs_h2645.c:401
AVFMT_GENERIC_INDEX
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:480
val
static double val(void *priv, double ch)
Definition: aeval.c:77
av_get_bits_per_sample
int av_get_bits_per_sample(enum AVCodecID codec_id)
Return codec bits per sample.
Definition: utils.c:550
avassert.h
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
pcm_options
static const AVOption pcm_options[]
Definition: pcmdec.c:107
read_packet
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_read_callback.c:42
s
#define s(width, name)
Definition: cbs_vp9.c:198
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:553
pcm_demuxer_class
static const AVClass pcm_demuxer_class
Definition: pcmdec.c:112
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
PCM
#define PCM(format)
Definition: avisynth.c:52
av_assert0
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:40
channels
channels
Definition: aptx.h:31
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:47
ff_sln_demuxer
const FFInputFormat ff_sln_demuxer
AVFormatContext
Format I/O context.
Definition: avformat.h:1287
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:771
LIBAVUTIL_VERSION_INT
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:535
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
NULL
#define NULL
Definition: coverity.c:32
av_default_item_name
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:237
PCMAudioDemuxerContext::ch_layout
AVChannelLayout ch_layout
Definition: pcmdec.c:38
AV_OPT_TYPE_CHLAYOUT
@ AV_OPT_TYPE_CHLAYOUT
Underlying C type is AVChannelLayout.
Definition: opt.h:331
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:180
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:184
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:94
AVChannelLayout
An AVChannelLayout holds information about the channel layout of audio data.
Definition: channel_layout.h:311
FFInputFormat::p
AVInputFormat p
The public AVInputFormat.
Definition: demux.h:41
PCMAudioDemuxerContext::sample_rate
int sample_rate
Definition: pcmdec.c:37
log.h
AVCodecParameters::block_align
int block_align
Audio only.
Definition: codec_par.h:191
FFInputFormat::raw_codec_id
enum AVCodecID raw_codec_id
Raw demuxers store their codec ID here.
Definition: demux.h:46
demux.h
ff_pcm_read_packet
int ff_pcm_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: pcm.c:57
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:748
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:73
avformat.h
channel_layout.h
ffifmt
static const FFInputFormat * ffifmt(const AVInputFormat *fmt)
Definition: demux.h:133
AV_OPT_TYPE_INT
@ AV_OPT_TYPE_INT
Underlying C type is int.
Definition: opt.h:259
av_channel_layout_uninit
void av_channel_layout_uninit(AVChannelLayout *channel_layout)
Free any allocated data in the channel layout and reset the channel count to 0.
Definition: channel_layout.c:437
av_channel_layout_copy
int av_channel_layout_copy(AVChannelLayout *dst, const AVChannelLayout *src)
Make a copy of a channel layout.
Definition: channel_layout.c:444
PCMAudioDemuxerContext
Definition: pcmdec.c:35
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:356
AVCodecParameters::bits_per_coded_sample
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: codec_par.h:110
mem.h
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:55
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:34
FFInputFormat
Definition: demux.h:37
pcm_read_header
static int pcm_read_header(AVFormatContext *s)
Definition: pcmdec.c:41
S8
static const uint32_t S8[256]
Definition: cast5.c:328
av_opt_get
int av_opt_get(void *obj, const char *name, int search_flags, uint8_t **out_val)
Definition: opt.c:1160
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
avstring.h
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