Libav
mp3enc.c
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1 /*
2  * MP3 muxer
3  * Copyright (c) 2003 Fabrice Bellard
4  *
5  * This file is part of Libav.
6  *
7  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "avformat.h"
23 #include "avio_internal.h"
24 #include "id3v1.h"
25 #include "id3v2.h"
26 #include "rawenc.h"
27 #include "libavutil/avstring.h"
28 #include "libavcodec/mpegaudio.h"
31 #include "libavutil/intreadwrite.h"
32 #include "libavutil/opt.h"
33 #include "libavutil/dict.h"
34 #include "libavutil/avassert.h"
35 
36 static int id3v1_set_string(AVFormatContext *s, const char *key,
37  uint8_t *buf, int buf_size)
38 {
40  if ((tag = av_dict_get(s->metadata, key, NULL, 0)))
41  av_strlcpy(buf, tag->value, buf_size);
42  return !!tag;
43 }
44 
46 {
48  int i, count = 0;
49 
50  memset(buf, 0, ID3v1_TAG_SIZE); /* fail safe */
51  buf[0] = 'T';
52  buf[1] = 'A';
53  buf[2] = 'G';
54  count += id3v1_set_string(s, "TIT2", buf + 3, 30); //title
55  count += id3v1_set_string(s, "TPE1", buf + 33, 30); //author|artist
56  count += id3v1_set_string(s, "TALB", buf + 63, 30); //album
57  count += id3v1_set_string(s, "TDRL", buf + 93, 4); //date
58  count += id3v1_set_string(s, "comment", buf + 97, 30);
59  if ((tag = av_dict_get(s->metadata, "TRCK", NULL, 0))) { //track
60  buf[125] = 0;
61  buf[126] = atoi(tag->value);
62  count++;
63  }
64  buf[127] = 0xFF; /* default to unknown genre */
65  if ((tag = av_dict_get(s->metadata, "TCON", NULL, 0))) { //genre
66  for(i = 0; i <= ID3v1_GENRE_MAX; i++) {
67  if (!av_strcasecmp(tag->value, ff_id3v1_genre_str[i])) {
68  buf[127] = i;
69  count++;
70  break;
71  }
72  }
73  }
74  return count;
75 }
76 
77 #define XING_NUM_BAGS 400
78 #define XING_TOC_SIZE 100
79 // maximum size of the xing frame: offset/Xing/flags/frames/size/TOC
80 #define XING_MAX_SIZE (32 + 4 + 4 + 4 + 4 + XING_TOC_SIZE)
81 
82 typedef struct MP3Context {
83  const AVClass *class;
88 
89  /* xing header */
90  int64_t xing_offset;
93  uint32_t want;
94  uint32_t seen;
95  uint32_t pos;
96  uint64_t bag[XING_NUM_BAGS];
99 
100  /* index of the audio stream */
102  /* number of attached pictures we still need to write */
104 
105  /* audio packets are queued here until we get all the attached pictures */
107 } MP3Context;
108 
109 static const uint8_t xing_offtbl[2][2] = {{32, 17}, {17, 9}};
110 
111 /*
112  * Write an empty XING header and initialize respective data.
113  */
115 {
116  MP3Context *mp3 = s->priv_data;
117  AVCodecContext *codec = s->streams[mp3->audio_stream_idx]->codec;
118  int32_t header;
119  MPADecodeHeader mpah;
120  int srate_idx, i, channels;
121  int bitrate_idx;
122  int best_bitrate_idx;
123  int best_bitrate_error = INT_MAX;
124  int xing_offset;
125  int ver = 0;
126  int lsf, bytes_needed;
127 
128  if (!s->pb->seekable || !mp3->write_xing)
129  return;
130 
131  for (i = 0; i < FF_ARRAY_ELEMS(avpriv_mpa_freq_tab); i++) {
132  const uint16_t base_freq = avpriv_mpa_freq_tab[i];
133 
134  if (codec->sample_rate == base_freq) ver = 0x3; // MPEG 1
135  else if (codec->sample_rate == base_freq / 2) ver = 0x2; // MPEG 2
136  else if (codec->sample_rate == base_freq / 4) ver = 0x0; // MPEG 2.5
137  else continue;
138 
139  srate_idx = i;
140  break;
141  }
143  av_log(s, AV_LOG_WARNING, "Unsupported sample rate, not writing Xing "
144  "header.\n");
145  return;
146  }
147 
148  switch (codec->channels) {
149  case 1: channels = MPA_MONO; break;
150  case 2: channels = MPA_STEREO; break;
151  default: av_log(s, AV_LOG_WARNING, "Unsupported number of channels, "
152  "not writing Xing header.\n");
153  return;
154  }
155 
156  /* dummy MPEG audio header */
157  header = 0xff << 24; // sync
158  header |= (0x7 << 5 | ver << 3 | 0x1 << 1 | 0x1) << 16; // sync/audio-version/layer 3/no crc*/
159  header |= (srate_idx << 2) << 8;
160  header |= channels << 6;
161 
162  lsf = !((header & (1 << 20) && header & (1 << 19)));
163 
164  xing_offset = xing_offtbl[ver != 3][channels == 1];
165  bytes_needed = 4 // header
166  + xing_offset
167  + 4 // xing tag
168  + 4 // frames/size/toc flags
169  + 4 // frames
170  + 4 // size
171  + XING_TOC_SIZE; // toc
172 
173  for (bitrate_idx = 1; bitrate_idx < 15; bitrate_idx++) {
174  int bit_rate = 1000 * avpriv_mpa_bitrate_tab[lsf][3 - 1][bitrate_idx];
175  int error = FFABS(bit_rate - codec->bit_rate);
176 
177  if (error < best_bitrate_error){
178  best_bitrate_error = error;
179  best_bitrate_idx = bitrate_idx;
180  }
181  }
182 
183  for (bitrate_idx = best_bitrate_idx; bitrate_idx < 15; bitrate_idx++) {
184  int32_t mask = bitrate_idx << (4 + 8);
185  header |= mask;
186 
187  avpriv_mpegaudio_decode_header(&mpah, header);
188 
189  if (bytes_needed <= mpah.frame_size)
190  break;
191 
192  header &= ~mask;
193  }
194 
195  avio_wb32(s->pb, header);
196 
197  avpriv_mpegaudio_decode_header(&mpah, header);
198 
199  av_assert0(mpah.frame_size >= bytes_needed);
200 
201  ffio_fill(s->pb, 0, xing_offset);
202  mp3->xing_offset = avio_tell(s->pb);
203  ffio_wfourcc(s->pb, "Xing");
204  avio_wb32(s->pb, 0x01 | 0x02 | 0x04); // frames / size / TOC
205 
206  mp3->size = mpah.frame_size;
207  mp3->want = 1;
208 
209  avio_wb32(s->pb, 0); // frames
210  avio_wb32(s->pb, 0); // size
211 
212  // TOC
213  for (i = 0; i < XING_TOC_SIZE; i++)
214  avio_w8(s->pb, 255 * i / XING_TOC_SIZE);
215 
216  ffio_fill(s->pb, 0, mpah.frame_size - bytes_needed);
217 }
218 
219 /*
220  * Add a frame to XING data.
221  * Following lame's "VbrTag.c".
222  */
223 static void mp3_xing_add_frame(MP3Context *mp3, AVPacket *pkt)
224 {
225  int i;
226 
227  mp3->frames++;
228  mp3->seen++;
229  mp3->size += pkt->size;
230 
231  if (mp3->want == mp3->seen) {
232  mp3->bag[mp3->pos] = mp3->size;
233 
234  if (XING_NUM_BAGS == ++mp3->pos) {
235  /* shrink table to half size by throwing away each second bag. */
236  for (i = 1; i < XING_NUM_BAGS; i += 2)
237  mp3->bag[i / 2] = mp3->bag[i];
238 
239  /* double wanted amount per bag. */
240  mp3->want *= 2;
241  /* adjust current position to half of table size. */
242  mp3->pos = XING_NUM_BAGS / 2;
243  }
244 
245  mp3->seen = 0;
246  }
247 }
248 
250 {
251  MP3Context *mp3 = s->priv_data;
252 
253  if (mp3->xing_offset && pkt->size >= 4) {
254  MPADecodeHeader c;
255  uint32_t h;
256 
257  h = AV_RB32(pkt->data);
258  if (ff_mpa_check_header(h) == 0) {
260  if (!mp3->initial_bitrate)
261  mp3->initial_bitrate = c.bit_rate;
262  if ((c.bit_rate == 0) || (mp3->initial_bitrate != c.bit_rate))
263  mp3->has_variable_bitrate = 1;
264  }
265 
266  mp3_xing_add_frame(mp3, pkt);
267  }
268 
269  return ff_raw_write_packet(s, pkt);
270 }
271 
273 {
274  MP3Context *mp3 = s->priv_data;
275  AVPacketList *pktl;
276  int ret = 0, write = 1;
277 
278  ff_id3v2_finish(&mp3->id3, s->pb);
279  mp3_write_xing(s);
280 
281  while ((pktl = mp3->queue)) {
282  if (write && (ret = mp3_write_audio_packet(s, &pktl->pkt)) < 0)
283  write = 0;
284  av_free_packet(&pktl->pkt);
285  mp3->queue = pktl->next;
286  av_freep(&pktl);
287  }
288  mp3->queue_end = NULL;
289  return ret;
290 }
291 
293 {
294  MP3Context *mp3 = s->priv_data;
295  int i;
296 
297  /* replace "Xing" identification string with "Info" for CBR files. */
298  if (!mp3->has_variable_bitrate) {
299  avio_seek(s->pb, mp3->xing_offset, SEEK_SET);
300  ffio_wfourcc(s->pb, "Info");
301  }
302 
303  avio_seek(s->pb, mp3->xing_offset + 8, SEEK_SET);
304  avio_wb32(s->pb, mp3->frames);
305  avio_wb32(s->pb, mp3->size);
306 
307  avio_w8(s->pb, 0); // first toc entry has to be zero.
308 
309  for (i = 1; i < XING_TOC_SIZE; ++i) {
310  int j = i * mp3->pos / XING_TOC_SIZE;
311  int seek_point = 256LL * mp3->bag[j] / mp3->size;
312  avio_w8(s->pb, FFMIN(seek_point, 255));
313  }
314 
315  avio_seek(s->pb, 0, SEEK_END);
316 }
317 
318 static int mp3_write_trailer(struct AVFormatContext *s)
319 {
320  uint8_t buf[ID3v1_TAG_SIZE];
321  MP3Context *mp3 = s->priv_data;
322 
323  if (mp3->pics_to_write) {
324  av_log(s, AV_LOG_WARNING, "No packets were sent for some of the "
325  "attached pictures.\n");
326  mp3_queue_flush(s);
327  }
328 
329  /* write the id3v1 tag */
330  if (mp3->write_id3v1 && id3v1_create_tag(s, buf) > 0) {
331  avio_write(s->pb, buf, ID3v1_TAG_SIZE);
332  }
333 
334  if (mp3->xing_offset)
335  mp3_update_xing(s);
336 
337  return 0;
338 }
339 
340 #if CONFIG_MP2_MUXER
341 AVOutputFormat ff_mp2_muxer = {
342  .name = "mp2",
343  .long_name = NULL_IF_CONFIG_SMALL("MP2 (MPEG audio layer 2)"),
344  .mime_type = "audio/x-mpeg",
345  .extensions = "mp2,m2a,mpa",
346  .audio_codec = AV_CODEC_ID_MP2,
347  .video_codec = AV_CODEC_ID_NONE,
348  .write_packet = ff_raw_write_packet,
349  .flags = AVFMT_NOTIMESTAMPS,
350 };
351 #endif
352 
353 #if CONFIG_MP3_MUXER
354 
355 static const AVOption options[] = {
356  { "id3v2_version", "Select ID3v2 version to write. Currently 3 and 4 are supported.",
357  offsetof(MP3Context, id3v2_version), AV_OPT_TYPE_INT, {.i64 = 4}, 0, 4, AV_OPT_FLAG_ENCODING_PARAM},
358  { "write_id3v1", "Enable ID3v1 writing. ID3v1 tags are written in UTF-8 which may not be supported by most software.",
359  offsetof(MP3Context, write_id3v1), AV_OPT_TYPE_INT, {.i64 = 0}, 0, 1, AV_OPT_FLAG_ENCODING_PARAM},
360  { "write_xing", "Write the Xing header containing file duration.",
361  offsetof(MP3Context, write_xing), AV_OPT_TYPE_INT, {.i64 = 1}, 0, 1, AV_OPT_FLAG_ENCODING_PARAM},
362  { NULL },
363 };
364 
365 static const AVClass mp3_muxer_class = {
366  .class_name = "MP3 muxer",
367  .item_name = av_default_item_name,
368  .option = options,
369  .version = LIBAVUTIL_VERSION_INT,
370 };
371 
372 static int mp3_write_packet(AVFormatContext *s, AVPacket *pkt)
373 {
374  MP3Context *mp3 = s->priv_data;
375 
376  if (pkt->stream_index == mp3->audio_stream_idx) {
377  if (mp3->pics_to_write) {
378  /* buffer audio packets until we get all the pictures */
379  AVPacketList *pktl = av_mallocz(sizeof(*pktl));
380  if (!pktl)
381  return AVERROR(ENOMEM);
382 
383  pktl->pkt = *pkt;
384  pktl->pkt.buf = av_buffer_ref(pkt->buf);
385  if (!pktl->pkt.buf) {
386  av_freep(&pktl);
387  return AVERROR(ENOMEM);
388  }
389 
390  if (mp3->queue_end)
391  mp3->queue_end->next = pktl;
392  else
393  mp3->queue = pktl;
394  mp3->queue_end = pktl;
395  } else
396  return mp3_write_audio_packet(s, pkt);
397  } else {
398  int ret;
399 
400  /* warn only once for each stream */
401  if (s->streams[pkt->stream_index]->nb_frames == 1) {
402  av_log(s, AV_LOG_WARNING, "Got more than one picture in stream %d,"
403  " ignoring.\n", pkt->stream_index);
404  }
405  if (!mp3->pics_to_write || s->streams[pkt->stream_index]->nb_frames >= 1)
406  return 0;
407 
408  if ((ret = ff_id3v2_write_apic(s, &mp3->id3, pkt)) < 0)
409  return ret;
410  mp3->pics_to_write--;
411 
412  /* flush the buffered audio packets */
413  if (!mp3->pics_to_write &&
414  (ret = mp3_queue_flush(s)) < 0)
415  return ret;
416  }
417 
418  return 0;
419 }
420 
425 static int mp3_write_header(struct AVFormatContext *s)
426 {
427  MP3Context *mp3 = s->priv_data;
428  int ret, i;
429 
430  if (mp3->id3v2_version &&
431  mp3->id3v2_version != 3 &&
432  mp3->id3v2_version != 4) {
433  av_log(s, AV_LOG_ERROR, "Invalid ID3v2 version requested: %d. Only "
434  "3, 4 or 0 (disabled) are allowed.\n", mp3->id3v2_version);
435  return AVERROR(EINVAL);
436  }
437 
438  /* check the streams -- we want exactly one audio and arbitrary number of
439  * video (attached pictures) */
440  mp3->audio_stream_idx = -1;
441  for (i = 0; i < s->nb_streams; i++) {
442  AVStream *st = s->streams[i];
443  if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {
444  if (mp3->audio_stream_idx >= 0 || st->codec->codec_id != AV_CODEC_ID_MP3) {
445  av_log(s, AV_LOG_ERROR, "Invalid audio stream. Exactly one MP3 "
446  "audio stream is required.\n");
447  return AVERROR(EINVAL);
448  }
449  mp3->audio_stream_idx = i;
450  } else if (st->codec->codec_type != AVMEDIA_TYPE_VIDEO) {
451  av_log(s, AV_LOG_ERROR, "Only audio streams and pictures are allowed in MP3.\n");
452  return AVERROR(EINVAL);
453  }
454  }
455  if (mp3->audio_stream_idx < 0) {
456  av_log(s, AV_LOG_ERROR, "No audio stream present.\n");
457  return AVERROR(EINVAL);
458  }
459  mp3->pics_to_write = s->nb_streams - 1;
460 
461  if (mp3->pics_to_write && !mp3->id3v2_version) {
462  av_log(s, AV_LOG_ERROR, "Attached pictures were requested, but the "
463  "ID3v2 header is disabled.\n");
464  return AVERROR(EINVAL);
465  }
466 
467  if (mp3->id3v2_version) {
469  ret = ff_id3v2_write_metadata(s, &mp3->id3);
470  if (ret < 0)
471  return ret;
472  }
473 
474  if (!mp3->pics_to_write) {
475  if (mp3->id3v2_version)
476  ff_id3v2_finish(&mp3->id3, s->pb);
477  mp3_write_xing(s);
478  }
479 
480  return 0;
481 }
482 
483 AVOutputFormat ff_mp3_muxer = {
484  .name = "mp3",
485  .long_name = NULL_IF_CONFIG_SMALL("MP3 (MPEG audio layer 3)"),
486  .mime_type = "audio/x-mpeg",
487  .extensions = "mp3",
488  .priv_data_size = sizeof(MP3Context),
489  .audio_codec = AV_CODEC_ID_MP3,
490  .video_codec = AV_CODEC_ID_PNG,
491  .write_header = mp3_write_header,
492  .write_packet = mp3_write_packet,
495  .priv_class = &mp3_muxer_class,
496 };
497 #endif
#define MPA_STEREO
Definition: mpegaudio.h:45
#define XING_NUM_BAGS
Definition: mp3enc.c:77
void av_free_packet(AVPacket *pkt)
Free a packet.
Definition: avpacket.c:243
AVOption.
Definition: opt.h:234
void ff_id3v2_start(ID3v2EncContext *id3, AVIOContext *pb, int id3v2_version, const char *magic)
Initialize an ID3v2 tag.
Definition: id3v2enc.c:113
static int mp3_write_audio_packet(AVFormatContext *s, AVPacket *pkt)
Definition: mp3enc.c:249
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:129
uint32_t pos
Definition: mp3enc.c:95
static int write_packet(AVFormatContext *s, AVPacket *pkt)
Definition: assenc.c:58
int size
Definition: avcodec.h:974
#define ID3v2_DEFAULT_MAGIC
Default magic bytes for ID3v2 header: "ID3".
Definition: id3v2.h:35
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:186
#define FF_ARRAY_ELEMS(a)
mpeg audio layer common tables.
uint64_t bag[XING_NUM_BAGS]
Definition: mp3enc.c:96
void av_freep(void *arg)
Free a memory block which has been allocated with av_malloc(z)() or av_realloc() and set the pointer ...
Definition: mem.c:198
Format I/O context.
Definition: avformat.h:922
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:38
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:37
Public dictionary API.
static void mp3_update_xing(AVFormatContext *s)
Definition: mp3enc.c:292
int32_t size
Definition: mp3enc.c:92
static int mp3_write_trailer(struct AVFormatContext *s)
Definition: mp3enc.c:318
uint8_t
AVOptions.
AVPacket pkt
Definition: avformat.h:1260
#define AV_RB32
Definition: intreadwrite.h:130
const uint16_t avpriv_mpa_freq_tab[3]
Definition: mpegaudiodata.c:40
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:990
AVDictionaryEntry * av_dict_get(const AVDictionary *m, const char *key, const AVDictionaryEntry *prev, int flags)
Get a dictionary entry with matching key.
Definition: dict.c:38
uint8_t * data
Definition: avcodec.h:973
int avpriv_mpegaudio_decode_header(MPADecodeHeader *s, uint32_t header)
static int flags
Definition: log.c:44
uint32_t tag
Definition: movenc.c:844
static const uint8_t xing_offtbl[2][2]
Definition: mp3enc.c:109
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:219
void avio_write(AVIOContext *s, const unsigned char *buf, int size)
Definition: aviobuf.c:165
static av_always_inline void ffio_wfourcc(AVIOContext *pb, const uint8_t *s)
Definition: avio_internal.h:67
static int write_trailer(AVFormatContext *s)
Definition: assenc.c:64
#define AV_OPT_FLAG_ENCODING_PARAM
a generic parameter which can be set by the user for muxing or encoding
Definition: opt.h:264
AVPacketList * queue_end
Definition: mp3enc.c:106
const OptionDef options[]
Definition: avconv_opt.c:2187
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:123
AVDictionary * metadata
Metadata that applies to the whole file.
Definition: avformat.h:1130
int64_t xing_offset
Definition: mp3enc.c:90
static const uint16_t mask[17]
Definition: lzw.c:38
#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:150
preferred ID for decoding MPEG audio layer 1, 2 or 3
Definition: avcodec.h:379
AVBufferRef * buf
A reference to the reference-counted buffer where the packet data is stored.
Definition: avcodec.h:956
simple assert() macros that are a bit more flexible than ISO C assert().
void av_log(void *avcl, int level, const char *fmt,...)
Definition: log.c:169
uint32_t want
Definition: mp3enc.c:93
static int ff_mpa_check_header(uint32_t header)
void ff_id3v2_finish(ID3v2EncContext *id3, AVIOContext *pb)
Finalize an opened ID3v2 tag.
Definition: id3v2enc.c:224
size_t av_strlcpy(char *dst, const char *src, size_t size)
Copy the string src to dst, but no more than size - 1 bytes, and null-terminate dst.
Definition: avstring.c:81
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:718
int initial_bitrate
Definition: mp3enc.c:97
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
Definition: avformat.h:978
int seekable
A combination of AVIO_SEEKABLE_ flags or 0 when the stream is not seekable.
Definition: avio.h:117
int bit_rate
the average bitrate
Definition: avcodec.h:1114
int ff_id3v2_write_metadata(AVFormatContext *s, ID3v2EncContext *id3)
Convert and write all global metadata from s into an ID3v2 tag.
Definition: id3v2enc.c:127
void ffio_fill(AVIOContext *s, int b, int count)
Definition: aviobuf.c:151
int id3v2_version
Definition: mp3enc.c:85
#define FFMIN(a, b)
Definition: common.h:57
int av_strcasecmp(const char *a, const char *b)
Definition: avstring.c:156
const char * name
Definition: avformat.h:446
int32_t
AVPacketList * queue
Definition: mp3enc.c:106
#define FFABS(a)
Definition: common.h:52
int ff_raw_write_packet(AVFormatContext *s, AVPacket *pkt)
Definition: rawenc.c:26
int write_id3v1
Definition: mp3enc.c:86
static void mp3_write_xing(AVFormatContext *s)
Definition: mp3enc.c:114
LIBAVUTIL_VERSION_INT
Definition: eval.c:55
Stream structure.
Definition: avformat.h:699
int pics_to_write
Definition: mp3enc.c:103
#define AVFMT_NOTIMESTAMPS
Format does not need / have any timestamps.
Definition: avformat.h:416
NULL
Definition: eval.c:55
int has_variable_bitrate
Definition: mp3enc.c:98
int audio_stream_idx
Definition: mp3enc.c:101
enum AVMediaType codec_type
Definition: avcodec.h:1058
enum AVCodecID codec_id
Definition: avcodec.h:1067
int sample_rate
samples per second
Definition: avcodec.h:1791
AVIOContext * pb
I/O context.
Definition: avformat.h:964
int32_t frames
Definition: mp3enc.c:91
av_default_item_name
Definition: dnxhdenc.c:52
void avio_w8(AVIOContext *s, int b)
Definition: aviobuf.c:144
main external API structure.
Definition: avcodec.h:1050
Describe the class of an AVClass context structure.
Definition: log.h:33
#define MPA_MONO
Definition: mpegaudio.h:48
static int id3v1_set_string(AVFormatContext *s, const char *key, uint8_t *buf, int buf_size)
Definition: mp3enc.c:36
int ff_id3v2_write_apic(AVFormatContext *s, ID3v2EncContext *id3, AVPacket *pkt)
Write an attached picture from pkt into an ID3v2 tag.
Definition: id3v2enc.c:159
int write_xing
Definition: mp3enc.c:87
MPEG Audio header decoder.
static int mp3_queue_flush(AVFormatContext *s)
Definition: mp3enc.c:272
Main libavformat public API header.
struct AVPacketList * next
Definition: avformat.h:1261
AVBufferRef * av_buffer_ref(AVBufferRef *buf)
Create a new reference to an AVBuffer.
Definition: buffer.c:92
mpeg audio declarations for both encoder and decoder.
int64_t nb_frames
number of frames in this stream if known or 0
Definition: avformat.h:758
#define XING_TOC_SIZE
Definition: mp3enc.c:78
char * value
Definition: dict.h:76
int channels
number of audio channels
Definition: avcodec.h:1792
void * priv_data
Format private data.
Definition: avformat.h:950
static void write_header(FFV1Context *f)
Definition: ffv1enc.c:380
#define ID3v1_TAG_SIZE
Definition: id3v1.h:27
void avio_wb32(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:268
const uint16_t avpriv_mpa_bitrate_tab[2][3][15]
Definition: mpegaudiodata.c:30
int stream_index
Definition: avcodec.h:975
static int id3v1_create_tag(AVFormatContext *s, uint8_t *buf)
Definition: mp3enc.c:45
#define ID3v1_GENRE_MAX
Definition: id3v1.h:29
const char *const ff_id3v1_genre_str[ID3v1_GENRE_MAX+1]
ID3v1 genres.
Definition: id3v1.c:26
This structure stores compressed data.
Definition: avcodec.h:950
void * av_mallocz(size_t size)
Allocate a block of size bytes with alignment suitable for all memory accesses (including vectors if ...
Definition: mem.c:205
ID3v2EncContext id3
Definition: mp3enc.c:84
static void mp3_xing_add_frame(MP3Context *mp3, AVPacket *pkt)
Definition: mp3enc.c:223
uint32_t seen
Definition: mp3enc.c:94