FFmpeg
amr.c
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1 /*
2  * amr file format
3  * Copyright (c) 2001 FFmpeg project
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 /*
23 Write and read amr data according to RFC3267, http://www.ietf.org/rfc/rfc3267.txt?number=3267
24 */
25 
27 #include "libavutil/intreadwrite.h"
28 #include "avformat.h"
29 #include "avio_internal.h"
30 #include "internal.h"
31 #include "rawdec.h"
32 #include "rawenc.h"
33 
34 typedef struct AMRContext {
36 } AMRContext;
37 
38 static const uint8_t AMR_header[6] = "#!AMR\x0a";
39 static const uint8_t AMRMC_header[12] = "#!AMR_MC1.0\x0a";
40 static const uint8_t AMRWB_header[9] = "#!AMR-WB\x0a";
41 static const uint8_t AMRWBMC_header[15] = "#!AMR-WB_MC1.0\x0a";
42 
43 static const uint8_t amrnb_packed_size[16] = {
44  13, 14, 16, 18, 20, 21, 27, 32, 6, 1, 1, 1, 1, 1, 1, 1
45 };
46 static const uint8_t amrwb_packed_size[16] = {
47  18, 24, 33, 37, 41, 47, 51, 59, 61, 6, 1, 1, 1, 1, 1, 1
48 };
49 
50 #if CONFIG_AMR_MUXER
51 static int amr_write_header(AVFormatContext *s)
52 {
53  AVIOContext *pb = s->pb;
54  AVCodecParameters *par = s->streams[0]->codecpar;
55 
56  s->priv_data = NULL;
57 
58  if (par->codec_id == AV_CODEC_ID_AMR_NB) {
59  avio_write(pb, AMR_header, sizeof(AMR_header) - 1); /* magic number */
60  } else if (par->codec_id == AV_CODEC_ID_AMR_WB) {
61  avio_write(pb, AMRWB_header, sizeof(AMRWB_header) - 1); /* magic number */
62  } else {
63  return -1;
64  }
65  return 0;
66 }
67 #endif /* CONFIG_AMR_MUXER */
68 
69 static int amr_probe(const AVProbeData *p)
70 {
71  // Only check for "#!AMR" which could be amr-wb, amr-nb.
72  // This will also trigger multichannel files: "#!AMR_MC1.0\n" and
73  // "#!AMR-WB_MC1.0\n"
74 
75  if (!memcmp(p->buf, AMR_header, 5))
76  return AVPROBE_SCORE_MAX;
77  else
78  return 0;
79 }
80 
81 /* amr input */
83 {
84  AVIOContext *pb = s->pb;
85  AVStream *st;
86  uint8_t header[19] = { 0 };
87  int read, back = 0, ret;
88 
89  ret = ffio_ensure_seekback(s->pb, sizeof(header));
90  if (ret < 0)
91  return ret;
92 
93  read = avio_read(pb, header, sizeof(header));
94  if (read < 0)
95  return ret;
96 
97  st = avformat_new_stream(s, NULL);
98  if (!st)
99  return AVERROR(ENOMEM);
100  if (!memcmp(header, AMR_header, sizeof(AMR_header))) {
101  st->codecpar->codec_tag = MKTAG('s', 'a', 'm', 'r');
103  st->codecpar->sample_rate = 8000;
104  st->codecpar->channels = 1;
106  back = read - sizeof(AMR_header);
107  } else if (!memcmp(header, AMRWB_header, sizeof(AMRWB_header))) {
108  st->codecpar->codec_tag = MKTAG('s', 'a', 'w', 'b');
110  st->codecpar->sample_rate = 16000;
111  st->codecpar->channels = 1;
113  back = read - sizeof(AMRWB_header);
114  } else if (!memcmp(header, AMRMC_header, sizeof(AMRMC_header))) {
115  st->codecpar->codec_tag = MKTAG('s', 'a', 'm', 'r');
117  st->codecpar->sample_rate = 8000;
118  st->codecpar->channels = AV_RL32(header + 12);
119  back = read - 4 - sizeof(AMRMC_header);
120  } else if (!memcmp(header, AMRWBMC_header, sizeof(AMRWBMC_header))) {
121  st->codecpar->codec_tag = MKTAG('s', 'a', 'w', 'b');
123  st->codecpar->sample_rate = 16000;
124  st->codecpar->channels = AV_RL32(header + 15);
125  back = read - 4 - sizeof(AMRWBMC_header);
126  } else {
127  return AVERROR_INVALIDDATA;
128  }
129 
130  if (st->codecpar->channels < 1)
131  return AVERROR_INVALIDDATA;
132 
135  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
136 
137  if (back > 0)
138  avio_seek(pb, -back, SEEK_CUR);
139 
140  return 0;
141 }
142 
143 #if CONFIG_AMR_DEMUXER
145  .name = "amr",
146  .long_name = NULL_IF_CONFIG_SMALL("3GPP AMR"),
147  .priv_data_size = sizeof(AMRContext),
152  .priv_class = &ff_raw_demuxer_class,
153 };
154 #endif
155 
156 #if CONFIG_AMRNB_DEMUXER
157 static int amrnb_probe(const AVProbeData *p)
158 {
159  int mode, i = 0, valid = 0, invalid = 0;
160  const uint8_t *b = p->buf;
161 
162  while (i < p->buf_size) {
163  mode = b[i] >> 3 & 0x0F;
164  if (mode < 9 && (b[i] & 0x4) == 0x4) {
165  int last = b[i];
166  int size = amrnb_packed_size[mode];
167  while (size--) {
168  if (b[++i] != last)
169  break;
170  }
171  if (size > 0) {
172  valid++;
173  i += size;
174  }
175  } else {
176  valid = 0;
177  invalid++;
178  i++;
179  }
180  }
181  if (valid > 100 && valid >> 4 > invalid)
182  return AVPROBE_SCORE_EXTENSION / 2 + 1;
183  return 0;
184 }
185 
186 static int amrnb_read_header(AVFormatContext *s)
187 {
189  if (!st)
190  return AVERROR(ENOMEM);
192  st->codecpar->sample_rate = 8000;
193  st->codecpar->channels = 1;
197  avpriv_set_pts_info(st, 64, 1, 8000);
198 
199  return 0;
200 }
201 
203  .name = "amrnb",
204  .long_name = NULL_IF_CONFIG_SMALL("raw AMR-NB"),
205  .priv_data_size = sizeof(AMRContext),
206  .read_probe = amrnb_probe,
207  .read_header = amrnb_read_header,
210  .priv_class = &ff_raw_demuxer_class,
211 };
212 #endif
213 
214 #if CONFIG_AMRWB_DEMUXER
215 static int amrwb_probe(const AVProbeData *p)
216 {
217  int mode, i = 0, valid = 0, invalid = 0;
218  const uint8_t *b = p->buf;
219 
220  while (i < p->buf_size) {
221  mode = b[i] >> 3 & 0x0F;
222  if (mode < 10 && (b[i] & 0x4) == 0x4) {
223  int last = b[i];
224  int size = amrwb_packed_size[mode];
225  while (size--) {
226  if (b[++i] != last)
227  break;
228  }
229  if (size > 0) {
230  valid++;
231  i += size;
232  }
233  } else {
234  valid = 0;
235  invalid++;
236  i++;
237  }
238  }
239  if (valid > 100 && valid >> 4 > invalid)
240  return AVPROBE_SCORE_EXTENSION / 2 + 1;
241  return 0;
242 }
243 
244 static int amrwb_read_header(AVFormatContext *s)
245 {
247  if (!st)
248  return AVERROR(ENOMEM);
250  st->codecpar->sample_rate = 16000;
251  st->codecpar->channels = 1;
255  avpriv_set_pts_info(st, 64, 1, 16000);
256 
257  return 0;
258 }
259 
261  .name = "amrwb",
262  .long_name = NULL_IF_CONFIG_SMALL("raw AMR-WB"),
263  .priv_data_size = sizeof(AMRContext),
264  .read_probe = amrwb_probe,
265  .read_header = amrwb_read_header,
268  .priv_class = &ff_raw_demuxer_class,
269 };
270 #endif
271 
272 #if CONFIG_AMR_MUXER
274  .name = "amr",
275  .long_name = NULL_IF_CONFIG_SMALL("3GPP AMR"),
276  .mime_type = "audio/amr",
277  .extensions = "amr",
278  .audio_codec = AV_CODEC_ID_AMR_NB,
279  .video_codec = AV_CODEC_ID_NONE,
280  .write_header = amr_write_header,
281  .write_packet = ff_raw_write_packet,
282  .flags = AVFMT_NOTIMESTAMPS,
283 };
284 #endif
AVOutputFormat::name
const char * name
Definition: avformat.h:496
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:724
AMRContext::rawctx
FFRawDemuxerContext rawctx
Definition: amr.c:35
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
AV_CH_LAYOUT_MONO
#define AV_CH_LAYOUT_MONO
Definition: channel_layout.h:90
AVFMT_NOTIMESTAMPS
#define AVFMT_NOTIMESTAMPS
Format does not need / have any timestamps.
Definition: avformat.h:467
b
#define b
Definition: input.c:40
AV_CODEC_ID_AMR_NB
@ AV_CODEC_ID_AMR_NB
Definition: codec_id.h:406
AVCodecParameters::codec_tag
uint32_t codec_tag
Additional information about the codec (corresponds to the AVI FOURCC).
Definition: codec_par.h:64
AV_CODEC_ID_AMR_WB
@ AV_CODEC_ID_AMR_WB
Definition: codec_id.h:407
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:458
AVCodecParameters::channels
int channels
Audio only.
Definition: codec_par.h:166
AMR_header
static const uint8_t AMR_header[6]
Definition: amr.c:38
ffstream
static av_always_inline FFStream * ffstream(AVStream *st)
Definition: internal.h:429
FFRawDemuxerContext
Definition: rawdec.h:36
AVFMT_GENERIC_INDEX
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:468
AVInputFormat
Definition: avformat.h:638
ff_raw_read_partial_packet
int ff_raw_read_partial_packet(AVFormatContext *s, AVPacket *pkt)
Definition: rawdec.c:34
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:643
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:448
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
ff_amrwb_demuxer
const AVInputFormat ff_amrwb_demuxer
ff_raw_write_packet
int ff_raw_write_packet(AVFormatContext *s, AVPacket *pkt)
Definition: rawenc.c:29
ff_amr_demuxer
const AVInputFormat ff_amr_demuxer
AMRContext
Definition: amrnbdec.c:100
FFStream::need_parsing
enum AVStreamParseType need_parsing
Definition: internal.h:402
ff_raw_demuxer_class
const AVClass ff_raw_demuxer_class
Definition: rawdec.c:142
AVFormatContext
Format I/O context.
Definition: avformat.h:1109
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1004
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:527
NULL
#define NULL
Definition: coverity.c:32
rawdec.h
amrnb_packed_size
static const uint8_t amrnb_packed_size[16]
Definition: amr.c:43
read_probe
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:446
AVPROBE_SCORE_EXTENSION
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:456
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:170
AVIOContext
Bytestream IO Context.
Definition: avio.h:161
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
size
int size
Definition: twinvq_data.h:10344
header
static const uint8_t header[24]
Definition: sdr2.c:67
avio_write
void avio_write(AVIOContext *s, const unsigned char *buf, int size)
Definition: aviobuf.c:218
ffio_ensure_seekback
int ffio_ensure_seekback(AVIOContext *s, int64_t buf_size)
Ensures that the requested seekback buffer size will be available.
Definition: aviobuf.c:1016
amrwb_packed_size
static const uint8_t amrwb_packed_size[16]
Definition: amr.c:46
ff_amr_muxer
const AVOutputFormat ff_amr_muxer
ff_amrnb_demuxer
const AVInputFormat ff_amrnb_demuxer
rawenc.h
AV_CODEC_ID_NONE
@ AV_CODEC_ID_NONE
Definition: codec_id.h:48
AVOutputFormat
Definition: avformat.h:495
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:271
avio_internal.h
AMRWBMC_header
static const uint8_t AMRWBMC_header[15]
Definition: amr.c:41
AMRMC_header
static const uint8_t AMRMC_header[12]
Definition: amr.c:39
ret
ret
Definition: filter_design.txt:187
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:857
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:246
amr_read_header
static int amr_read_header(AVFormatContext *s)
Definition: amr.c:82
avformat.h
AV_RL32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:92
channel_layout.h
mode
mode
Definition: ebur128.h:83
avio_read
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:625
AVSTREAM_PARSE_FULL_RAW
@ AVSTREAM_PARSE_FULL_RAW
full parsing and repack with timestamp and position generation by parser for raw this assumes that ea...
Definition: avformat.h:784
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:1146
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
AVCodecParameters::channel_layout
uint64_t channel_layout
Audio only.
Definition: codec_par.h:162
amr_probe
static int amr_probe(const AVProbeData *p)
Definition: amr.c:69
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
MKTAG
#define MKTAG(a, b, c, d)
Definition: macros.h:55
AMRWB_header
static const uint8_t AMRWB_header[9]
Definition: amr.c:40