FFmpeg  4.3.8
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 Only mono files are supported.
26 
27 */
28 
30 #include "avformat.h"
31 #include "internal.h"
32 #include "rawenc.h"
33 
34 typedef struct {
35  uint64_t cumulated_size;
36  uint64_t block_count;
37 } AMRContext;
38 
39 static const char AMR_header[] = "#!AMR\n";
40 static const char AMRWB_header[] = "#!AMR-WB\n";
41 
42 static const uint8_t amrnb_packed_size[16] = {
43  13, 14, 16, 18, 20, 21, 27, 32, 6, 1, 1, 1, 1, 1, 1, 1
44 };
45 static const uint8_t amrwb_packed_size[16] = {
46  18, 24, 33, 37, 41, 47, 51, 59, 61, 6, 1, 1, 1, 1, 1, 1
47 };
48 
49 #if CONFIG_AMR_MUXER
50 static int amr_write_header(AVFormatContext *s)
51 {
52  AVIOContext *pb = s->pb;
53  AVCodecParameters *par = s->streams[0]->codecpar;
54 
55  s->priv_data = NULL;
56 
57  if (par->codec_id == AV_CODEC_ID_AMR_NB) {
58  avio_write(pb, AMR_header, sizeof(AMR_header) - 1); /* magic number */
59  } else if (par->codec_id == AV_CODEC_ID_AMR_WB) {
60  avio_write(pb, AMRWB_header, sizeof(AMRWB_header) - 1); /* magic number */
61  } else {
62  return -1;
63  }
64  return 0;
65 }
66 #endif /* CONFIG_AMR_MUXER */
67 
68 static int amr_probe(const AVProbeData *p)
69 {
70  // Only check for "#!AMR" which could be amr-wb, amr-nb.
71  // This will also trigger multichannel files: "#!AMR_MC1.0\n" and
72  // "#!AMR-WB_MC1.0\n" (not supported)
73 
74  if (!memcmp(p->buf, AMR_header, 5))
75  return AVPROBE_SCORE_MAX;
76  else
77  return 0;
78 }
79 
80 /* amr input */
82 {
83  AVIOContext *pb = s->pb;
84  AVStream *st;
85  uint8_t header[9];
86 
87  if (avio_read(pb, header, 6) != 6)
88  return AVERROR_INVALIDDATA;
89 
90  st = avformat_new_stream(s, NULL);
91  if (!st)
92  return AVERROR(ENOMEM);
93  if (memcmp(header, AMR_header, 6)) {
94  if (avio_read(pb, header + 6, 3) != 3)
95  return AVERROR_INVALIDDATA;
96  if (memcmp(header, AMRWB_header, 9)) {
97  return -1;
98  }
99 
100  st->codecpar->codec_tag = MKTAG('s', 'a', 'w', 'b');
102  st->codecpar->sample_rate = 16000;
103  } else {
104  st->codecpar->codec_tag = MKTAG('s', 'a', 'm', 'r');
106  st->codecpar->sample_rate = 8000;
107  }
108  st->codecpar->channels = 1;
111  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
112 
113  return 0;
114 }
115 
117 {
118  AVCodecParameters *par = s->streams[0]->codecpar;
119  int read, size = 0, toc, mode;
120  int64_t pos = avio_tell(s->pb);
121  AMRContext *amr = s->priv_data;
122 
123  if (avio_feof(s->pb)) {
124  return AVERROR_EOF;
125  }
126 
127  // FIXME this is wrong, this should rather be in an AVParser
128  toc = avio_r8(s->pb);
129  mode = (toc >> 3) & 0x0F;
130 
131  if (par->codec_id == AV_CODEC_ID_AMR_NB) {
132  size = amrnb_packed_size[mode];
133  } else if (par->codec_id == AV_CODEC_ID_AMR_WB) {
134  size = amrwb_packed_size[mode];
135  }
136 
137  if (!size || av_new_packet(pkt, size))
138  return AVERROR(EIO);
139 
140  if (amr->cumulated_size < UINT64_MAX - size) {
141  amr->cumulated_size += size;
142  /* Both AMR formats have 50 frames per second */
143  s->streams[0]->codecpar->bit_rate = amr->cumulated_size / ++amr->block_count * 8 * 50;
144  }
145 
146  pkt->stream_index = 0;
147  pkt->pos = pos;
148  pkt->data[0] = toc;
149  pkt->duration = par->codec_id == AV_CODEC_ID_AMR_NB ? 160 : 320;
150  read = avio_read(s->pb, pkt->data + 1, size - 1);
151 
152  if (read != size - 1) {
153  if (read < 0)
154  return read;
155  return AVERROR(EIO);
156  }
157 
158  return 0;
159 }
160 
161 #if CONFIG_AMR_DEMUXER
163  .name = "amr",
164  .long_name = NULL_IF_CONFIG_SMALL("3GPP AMR"),
165  .priv_data_size = sizeof(AMRContext),
170 };
171 #endif
172 
173 #if CONFIG_AMRNB_DEMUXER
174 static int amrnb_probe(const AVProbeData *p)
175 {
176  int mode, i = 0, valid = 0, invalid = 0;
177  const uint8_t *b = p->buf;
178 
179  while (i < p->buf_size) {
180  mode = b[i] >> 3 & 0x0F;
181  if (mode < 9 && (b[i] & 0x4) == 0x4) {
182  int last = b[i];
183  int size = amrnb_packed_size[mode];
184  while (size--) {
185  if (b[++i] != last)
186  break;
187  }
188  if (size > 0) {
189  valid++;
190  i += size;
191  }
192  } else {
193  valid = 0;
194  invalid++;
195  i++;
196  }
197  }
198  if (valid > 100 && valid >> 4 > invalid)
199  return AVPROBE_SCORE_EXTENSION / 2 + 1;
200  return 0;
201 }
202 
203 static int amrnb_read_header(AVFormatContext *s)
204 {
206  if (!st)
207  return AVERROR(ENOMEM);
209  st->codecpar->sample_rate = 8000;
210  st->codecpar->channels = 1;
213  avpriv_set_pts_info(st, 64, 1, 8000);
214 
215  return 0;
216 }
217 
219  .name = "amrnb",
220  .long_name = NULL_IF_CONFIG_SMALL("raw AMR-NB"),
221  .priv_data_size = sizeof(AMRContext),
222  .read_probe = amrnb_probe,
223  .read_header = amrnb_read_header,
226 };
227 #endif
228 
229 #if CONFIG_AMRWB_DEMUXER
230 static int amrwb_probe(const AVProbeData *p)
231 {
232  int mode, i = 0, valid = 0, invalid = 0;
233  const uint8_t *b = p->buf;
234 
235  while (i < p->buf_size) {
236  mode = b[i] >> 3 & 0x0F;
237  if (mode < 10 && (b[i] & 0x4) == 0x4) {
238  int last = b[i];
239  int size = amrwb_packed_size[mode];
240  while (size--) {
241  if (b[++i] != last)
242  break;
243  }
244  if (size > 0) {
245  valid++;
246  i += size;
247  }
248  } else {
249  valid = 0;
250  invalid++;
251  i++;
252  }
253  }
254  if (valid > 100 && valid >> 4 > invalid)
255  return AVPROBE_SCORE_EXTENSION / 2 + 1;
256  return 0;
257 }
258 
259 static int amrwb_read_header(AVFormatContext *s)
260 {
262  if (!st)
263  return AVERROR(ENOMEM);
265  st->codecpar->sample_rate = 16000;
266  st->codecpar->channels = 1;
269  avpriv_set_pts_info(st, 64, 1, 16000);
270 
271  return 0;
272 }
273 
275  .name = "amrwb",
276  .long_name = NULL_IF_CONFIG_SMALL("raw AMR-WB"),
277  .priv_data_size = sizeof(AMRContext),
278  .read_probe = amrwb_probe,
279  .read_header = amrwb_read_header,
282 };
283 #endif
284 
285 #if CONFIG_AMR_MUXER
287  .name = "amr",
288  .long_name = NULL_IF_CONFIG_SMALL("3GPP AMR"),
289  .mime_type = "audio/amr",
290  .extensions = "amr",
291  .audio_codec = AV_CODEC_ID_AMR_NB,
292  .video_codec = AV_CODEC_ID_NONE,
293  .write_header = amr_write_header,
294  .write_packet = ff_raw_write_packet,
295  .flags = AVFMT_NOTIMESTAMPS,
296 };
297 #endif
#define NULL
Definition: coverity.c:32
Bytestream IO Context.
Definition: avio.h:161
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
int size
int64_t pos
byte position in stream, -1 if unknown
Definition: packet.h:375
void avpriv_set_pts_info(AVStream *s, 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:4948
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
uint64_t cumulated_size
Definition: amr.c:35
static int amr_read_header(AVFormatContext *s)
Definition: amr.c:81
const char * b
Definition: vf_curves.c:116
static AVPacket pkt
static const char AMR_header[]
Definition: amr.c:39
This struct describes the properties of an encoded stream.
Definition: codec_par.h:52
Format I/O context.
Definition: avformat.h:1351
uint8_t
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: packet.h:373
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4526
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1419
uint8_t * data
Definition: packet.h:355
static const char AMRWB_header[]
Definition: amr.c:40
#define AVERROR_EOF
End of file.
Definition: error.h:55
static const uint8_t amrnb_packed_size[16]
Definition: amr.c:42
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:557
AVInputFormat ff_amrwb_demuxer
static const uint8_t header[24]
Definition: sdr2.c:67
void avio_write(AVIOContext *s, const unsigned char *buf, int size)
Definition: aviobuf.c:213
uint64_t channel_layout
Audio only.
Definition: codec_par.h:162
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:625
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: codec_par.h:89
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:88
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:269
#define AVERROR(e)
Definition: error.h:43
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:188
unsigned int pos
Definition: spdifenc.c:412
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
AVOutputFormat ff_amr_muxer
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:616
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:443
audio channel layout utility functions
const char * name
Definition: avformat.h:500
#define s(width, name)
Definition: cbs_vp9.c:257
int ff_raw_write_packet(AVFormatContext *s, AVPacket *pkt)
Definition: rawenc.c:29
static const uint8_t amrwb_packed_size[16]
Definition: amr.c:45
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:545
Stream structure.
Definition: avformat.h:876
#define AVFMT_NOTIMESTAMPS
Format does not need / have any timestamps.
Definition: avformat.h:462
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
AVIOContext * pb
I/O context.
Definition: avformat.h:1393
long long int64_t
Definition: coverity.c:34
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:463
AVInputFormat ff_amr_demuxer
#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
#define flags(name, subs,...)
Definition: cbs_av1.c:576
static int amr_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: amr.c:116
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
AVInputFormat ff_amrnb_demuxer
uint64_t block_count
Definition: amr.c:36
int sample_rate
Audio only.
Definition: codec_par.h:170
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:453
Main libavformat public API header.
static int amr_probe(const AVProbeData *p)
Definition: amr.c:68
void * priv_data
Format private data.
Definition: avformat.h:1379
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:650
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1023
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:356
uint32_t codec_tag
Additional information about the codec (corresponds to the AVI FOURCC).
Definition: codec_par.h:64
int stream_index
Definition: packet.h:357
#define AV_CH_LAYOUT_MONO
#define MKTAG(a, b, c, d)
Definition: common.h:406
This structure stores compressed data.
Definition: packet.h:332
mode
Use these values in ebur128_init (or&#39;ed).
Definition: ebur128.h:83