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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 
33 typedef struct {
34  uint64_t cumulated_size;
35  uint64_t block_count;
36 } AMRContext;
37 
38 static const char AMR_header[] = "#!AMR\n";
39 static const char AMRWB_header[] = "#!AMR-WB\n";
40 
41 static const uint8_t amrnb_packed_size[16] = {
42  13, 14, 16, 18, 20, 21, 27, 32, 6, 1, 1, 1, 1, 1, 1, 1
43 };
44 static const uint8_t amrwb_packed_size[16] = {
45  18, 24, 33, 37, 41, 47, 51, 59, 61, 6, 1, 1, 1, 1, 1, 1
46 };
47 
48 #if CONFIG_AMR_MUXER
49 static int amr_write_header(AVFormatContext *s)
50 {
51  AVIOContext *pb = s->pb;
52  AVCodecParameters *par = s->streams[0]->codecpar;
53 
54  s->priv_data = NULL;
55 
56  if (par->codec_id == AV_CODEC_ID_AMR_NB) {
57  avio_write(pb, AMR_header, sizeof(AMR_header) - 1); /* magic number */
58  } else if (par->codec_id == AV_CODEC_ID_AMR_WB) {
59  avio_write(pb, AMRWB_header, sizeof(AMRWB_header) - 1); /* magic number */
60  } else {
61  return -1;
62  }
63  avio_flush(pb);
64  return 0;
65 }
66 
67 static int amr_write_packet(AVFormatContext *s, AVPacket *pkt)
68 {
69  avio_write(s->pb, pkt->data, pkt->size);
70  return 0;
71 }
72 #endif /* CONFIG_AMR_MUXER */
73 
74 static int amr_probe(AVProbeData *p)
75 {
76  // Only check for "#!AMR" which could be amr-wb, amr-nb.
77  // This will also trigger multichannel files: "#!AMR_MC1.0\n" and
78  // "#!AMR-WB_MC1.0\n" (not supported)
79 
80  if (!memcmp(p->buf, AMR_header, 5))
81  return AVPROBE_SCORE_MAX;
82  else
83  return 0;
84 }
85 
86 /* amr input */
88 {
89  AVIOContext *pb = s->pb;
90  AVStream *st;
91  uint8_t header[9];
92 
93  avio_read(pb, header, 6);
94 
95  st = avformat_new_stream(s, NULL);
96  if (!st)
97  return AVERROR(ENOMEM);
98  if (memcmp(header, AMR_header, 6)) {
99  avio_read(pb, header + 6, 3);
100  if (memcmp(header, AMRWB_header, 9)) {
101  return -1;
102  }
103 
104  st->codecpar->codec_tag = MKTAG('s', 'a', 'w', 'b');
106  st->codecpar->sample_rate = 16000;
107  } else {
108  st->codecpar->codec_tag = MKTAG('s', 'a', 'm', 'r');
110  st->codecpar->sample_rate = 8000;
111  }
112  st->codecpar->channels = 1;
115  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
116 
117  return 0;
118 }
119 
121 {
122  AVCodecParameters *par = s->streams[0]->codecpar;
123  int read, size = 0, toc, mode;
124  int64_t pos = avio_tell(s->pb);
125  AMRContext *amr = s->priv_data;
126 
127  if (avio_feof(s->pb)) {
128  return AVERROR_EOF;
129  }
130 
131  // FIXME this is wrong, this should rather be in an AVParser
132  toc = avio_r8(s->pb);
133  mode = (toc >> 3) & 0x0F;
134 
135  if (par->codec_id == AV_CODEC_ID_AMR_NB) {
136  size = amrnb_packed_size[mode];
137  } else if (par->codec_id == AV_CODEC_ID_AMR_WB) {
138  size = amrwb_packed_size[mode];
139  }
140 
141  if (!size || av_new_packet(pkt, size))
142  return AVERROR(EIO);
143 
144  if (amr->cumulated_size < UINT64_MAX - size) {
145  amr->cumulated_size += size;
146  /* Both AMR formats have 50 frames per second */
147  s->streams[0]->codecpar->bit_rate = amr->cumulated_size / ++amr->block_count * 8 * 50;
148  }
149 
150  pkt->stream_index = 0;
151  pkt->pos = pos;
152  pkt->data[0] = toc;
153  pkt->duration = par->codec_id == AV_CODEC_ID_AMR_NB ? 160 : 320;
154  read = avio_read(s->pb, pkt->data + 1, size - 1);
155 
156  if (read != size - 1) {
157  av_packet_unref(pkt);
158  if (read < 0)
159  return read;
160  return AVERROR(EIO);
161  }
162 
163  return 0;
164 }
165 
166 #if CONFIG_AMR_DEMUXER
167 AVInputFormat ff_amr_demuxer = {
168  .name = "amr",
169  .long_name = NULL_IF_CONFIG_SMALL("3GPP AMR"),
170  .priv_data_size = sizeof(AMRContext),
175 };
176 #endif
177 
178 #if CONFIG_AMRNB_DEMUXER
179 static int amrnb_probe(AVProbeData *p)
180 {
181  int mode, i = 0, valid = 0;
182  const uint8_t *b = p->buf;
183 
184  while (i < p->buf_size) {
185  mode = b[i] >> 3 & 0x0F;
186  if (mode < 9 && (b[i] & 0x4) == 0x4) {
187  int last = mode;
188  int size = amrnb_packed_size[mode];
189  while (size--) {
190  if (b[++i] != last)
191  break;
192  last = b[i];
193  }
194  if (size > 0) {
195  valid++;
196  i += size;
197  }
198  } else {
199  valid = 0;
200  i++;
201  }
202  }
203  if (valid > 100)
204  return AVPROBE_SCORE_EXTENSION / 2 + 1;
205  return 0;
206 }
207 
208 static int amrnb_read_header(AVFormatContext *s)
209 {
211  if (!st)
212  return AVERROR(ENOMEM);
214  st->codecpar->sample_rate = 8000;
215  st->codecpar->channels = 1;
218  avpriv_set_pts_info(st, 64, 1, 8000);
219 
220  return 0;
221 }
222 
223 AVInputFormat ff_amrnb_demuxer = {
224  .name = "amrnb",
225  .long_name = NULL_IF_CONFIG_SMALL("raw AMR-NB"),
226  .priv_data_size = sizeof(AMRContext),
227  .read_probe = amrnb_probe,
228  .read_header = amrnb_read_header,
231 };
232 #endif
233 
234 #if CONFIG_AMRWB_DEMUXER
235 static int amrwb_probe(AVProbeData *p)
236 {
237  int mode, i = 0, valid = 0;
238  const uint8_t *b = p->buf;
239 
240  while (i < p->buf_size) {
241  mode = b[i] >> 3 & 0x0F;
242  if (mode < 10 && (b[i] & 0x4) == 0x4) {
243  int last = mode;
244  int size = amrwb_packed_size[mode];
245  while (size--) {
246  if (b[++i] != last)
247  break;
248  last = b[i];
249  }
250  if (size > 0) {
251  valid++;
252  i += size;
253  }
254  } else {
255  valid = 0;
256  i++;
257  }
258  }
259  if (valid > 100)
260  return AVPROBE_SCORE_EXTENSION / 2 - 1;
261  return 0;
262 }
263 
264 static int amrwb_read_header(AVFormatContext *s)
265 {
267  if (!st)
268  return AVERROR(ENOMEM);
270  st->codecpar->sample_rate = 16000;
271  st->codecpar->channels = 1;
274  avpriv_set_pts_info(st, 64, 1, 16000);
275 
276  return 0;
277 }
278 
279 AVInputFormat ff_amrwb_demuxer = {
280  .name = "amrwb",
281  .long_name = NULL_IF_CONFIG_SMALL("raw AMR-WB"),
282  .priv_data_size = sizeof(AMRContext),
283  .read_probe = amrwb_probe,
284  .read_header = amrwb_read_header,
287 };
288 #endif
289 
290 #if CONFIG_AMR_MUXER
291 AVOutputFormat ff_amr_muxer = {
292  .name = "amr",
293  .long_name = NULL_IF_CONFIG_SMALL("3GPP AMR"),
294  .mime_type = "audio/amr",
295  .extensions = "amr",
296  .audio_codec = AV_CODEC_ID_AMR_NB,
297  .video_codec = AV_CODEC_ID_NONE,
298  .write_header = amr_write_header,
299  .write_packet = amr_write_packet,
300  .flags = AVFMT_NOTIMESTAMPS,
301 };
302 #endif
#define NULL
Definition: coverity.c:32
const char * s
Definition: avisynth_c.h:768
Bytestream IO Context.
Definition: avio.h:161
int64_t pos
byte position in stream, -1 if unknown
Definition: avcodec.h:1419
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:4747
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3736
uint64_t cumulated_size
Definition: amr.c:34
static int amr_read_header(AVFormatContext *s)
Definition: amr.c:87
int size
Definition: avcodec.h:1400
const char * b
Definition: vf_curves.c:113
static AVPacket pkt
static const char AMR_header[]
Definition: amr.c:38
This struct describes the properties of an encoded stream.
Definition: avcodec.h:3728
Format I/O context.
Definition: avformat.h:1325
uint8_t
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: avcodec.h:1417
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4377
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1393
uint8_t * data
Definition: avcodec.h:1399
static const char AMRWB_header[]
Definition: amr.c:39
static int flags
Definition: log.c:57
#define AVERROR_EOF
End of file.
Definition: error.h:55
static const uint8_t amrnb_packed_size[16]
Definition: amr.c:41
ptrdiff_t size
Definition: opengl_enc.c:101
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:558
static const uint8_t header[24]
Definition: sdr2.c:67
void avio_write(AVIOContext *s, const unsigned char *buf, int size)
Definition: aviobuf.c:216
uint64_t channel_layout
Audio only.
Definition: avcodec.h:3838
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:646
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: avcodec.h:3765
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:86
#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:190
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3732
static int amr_probe(AVProbeData *p)
Definition: amr.c:74
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:637
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:450
int void avio_flush(AVIOContext *s)
Force flushing of buffered data.
Definition: aviobuf.c:236
audio channel layout utility functions
static int read_probe(AVProbeData *pd)
Definition: jvdec.c:55
const char * name
Definition: avformat.h:507
static const uint8_t amrwb_packed_size[16]
Definition: amr.c:44
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:528
Stream structure.
Definition: avformat.h:872
#define AVFMT_NOTIMESTAMPS
Format does not need / have any timestamps.
Definition: avformat.h:469
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:1367
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:590
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:470
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:458
This structure contains the data a format has to probe a file.
Definition: avformat.h:448
static int amr_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: amr.c:120
uint64_t block_count
Definition: amr.c:35
int sample_rate
Audio only.
Definition: avcodec.h:3846
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:460
Main libavformat public API header.
void * priv_data
Format private data.
Definition: avformat.h:1353
int channels
Audio only.
Definition: avcodec.h:3842
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:647
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1014
int avio_feof(AVIOContext *s)
feof() equivalent for AVIOContext.
Definition: aviobuf.c:356
uint32_t codec_tag
Additional information about the codec (corresponds to the AVI FOURCC).
Definition: avcodec.h:3740
int stream_index
Definition: avcodec.h:1401
#define AV_CH_LAYOUT_MONO
#define MKTAG(a, b, c, d)
Definition: common.h:342
This structure stores compressed data.
Definition: avcodec.h:1376
mode
Use these values in ebur128_init (or'ed).
Definition: ebur128.h:83