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mp3dec.c
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1 /*
2  * MP3 demuxer
3  * Copyright (c) 2003 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 "libavutil/opt.h"
23 #include "libavutil/avstring.h"
24 #include "libavutil/intreadwrite.h"
25 #include "libavutil/crc.h"
26 #include "libavutil/dict.h"
27 #include "libavutil/mathematics.h"
28 #include "avformat.h"
29 #include "internal.h"
30 #include "avio_internal.h"
31 #include "id3v2.h"
32 #include "id3v1.h"
33 #include "replaygain.h"
34 
35 #include "libavcodec/avcodec.h"
37 
38 #define XING_FLAG_FRAMES 0x01
39 #define XING_FLAG_SIZE 0x02
40 #define XING_FLAG_TOC 0x04
41 #define XING_FLAC_QSCALE 0x08
42 
43 #define XING_TOC_COUNT 100
44 
45 typedef struct {
46  AVClass *class;
47  int64_t filesize;
48  int xing_toc;
49  int start_pad;
50  int end_pad;
51  int usetoc;
52  unsigned frames; /* Total number of frames in file */
53  unsigned header_filesize; /* Total number of bytes in the stream */
54  int is_cbr;
56 
57 static int check(AVFormatContext *s, int64_t pos);
58 
59 /* mp3 read */
60 
62 {
63  int max_frames, first_frames = 0;
64  int fsize, frames;
65  uint32_t header;
66  const uint8_t *buf, *buf0, *buf2, *end;
68 
69  if (!avctx)
70  return AVERROR(ENOMEM);
71 
72  buf0 = p->buf;
73  end = p->buf + p->buf_size - sizeof(uint32_t);
74  while(buf0 < end && !*buf0)
75  buf0++;
76 
77  max_frames = 0;
78  buf = buf0;
79 
80  for(; buf < end; buf= buf2+1) {
81  buf2 = buf;
82  if(ff_mpa_check_header(AV_RB32(buf2)))
83  continue;
84 
85  for(frames = 0; buf2 < end; frames++) {
86  int dummy;
87  header = AV_RB32(buf2);
88  fsize = avpriv_mpa_decode_header(avctx, header,
89  &dummy, &dummy, &dummy, &dummy);
90  if(fsize < 0)
91  break;
92  buf2 += fsize;
93  }
94  max_frames = FFMAX(max_frames, frames);
95  if(buf == buf0)
96  first_frames= frames;
97  }
98  avcodec_free_context(&avctx);
99  // keep this in sync with ac3 probe, both need to avoid
100  // issues with MPEG-files!
101  if (first_frames>=4) return AVPROBE_SCORE_EXTENSION + 1;
102  else if(max_frames>200)return AVPROBE_SCORE_EXTENSION;
103  else if(max_frames>=4 && max_frames >= p->buf_size/10000) return AVPROBE_SCORE_EXTENSION / 2;
104  else if(ff_id3v2_match(buf0, ID3v2_DEFAULT_MAGIC) && 2*ff_id3v2_tag_len(buf0) >= p->buf_size)
106  else if(max_frames>=1 && max_frames >= p->buf_size/10000) return 1;
107  else return 0;
108 //mpegps_mp3_unrecognized_format.mpg has max_frames=3
109 }
110 
111 static void read_xing_toc(AVFormatContext *s, int64_t filesize, int64_t duration)
112 {
113  int i;
114  MP3DecContext *mp3 = s->priv_data;
115  int fill_index = mp3->usetoc == 1 && duration > 0;
116 
117  if (!filesize &&
118  !(filesize = avio_size(s->pb))) {
119  av_log(s, AV_LOG_WARNING, "Cannot determine file size, skipping TOC table.\n");
120  fill_index = 0;
121  }
122 
123  for (i = 0; i < XING_TOC_COUNT; i++) {
124  uint8_t b = avio_r8(s->pb);
125  if (fill_index)
127  av_rescale(b, filesize, 256),
128  av_rescale(i, duration, XING_TOC_COUNT),
129  0, 0, AVINDEX_KEYFRAME);
130  }
131  if (fill_index)
132  mp3->xing_toc = 1;
133 }
134 
136  MPADecodeHeader *c, uint32_t spf)
137 {
138 #define LAST_BITS(k, n) ((k) & ((1 << (n)) - 1))
139 #define MIDDLE_BITS(k, m, n) LAST_BITS((k) >> (m), ((n) - (m)))
140 
141  uint16_t crc;
142  uint32_t v;
143 
144  char version[10];
145 
146  uint32_t peak = 0;
147  int32_t r_gain = INT32_MIN, a_gain = INT32_MIN;
148 
149  MP3DecContext *mp3 = s->priv_data;
150  static const int64_t xing_offtbl[2][2] = {{32, 17}, {17,9}};
151  uint64_t fsize = avio_size(s->pb);
152  fsize = fsize >= avio_tell(s->pb) ? fsize - avio_tell(s->pb) : 0;
153 
154  /* Check for Xing / Info tag */
155  avio_skip(s->pb, xing_offtbl[c->lsf == 1][c->nb_channels == 1]);
156  v = avio_rb32(s->pb);
157  mp3->is_cbr = v == MKBETAG('I', 'n', 'f', 'o');
158  if (v != MKBETAG('X', 'i', 'n', 'g') && !mp3->is_cbr)
159  return;
160 
161  v = avio_rb32(s->pb);
162  if (v & XING_FLAG_FRAMES)
163  mp3->frames = avio_rb32(s->pb);
164  if (v & XING_FLAG_SIZE)
165  mp3->header_filesize = avio_rb32(s->pb);
166  if (fsize && mp3->header_filesize) {
167  uint64_t min, delta;
168  min = FFMIN(fsize, mp3->header_filesize);
169  delta = FFMAX(fsize, mp3->header_filesize) - min;
170  if (fsize > mp3->header_filesize && delta > min >> 4) {
171  mp3->frames = 0;
173  "invalid concatenated file detected - using bitrate for duration\n");
174  } else if (delta > min >> 4) {
176  "filesize and duration do not match (growing file?)\n");
177  }
178  }
179  if (v & XING_FLAG_TOC)
181  (AVRational){spf, c->sample_rate},
182  st->time_base));
183  /* VBR quality */
184  if (v & XING_FLAC_QSCALE)
185  avio_rb32(s->pb);
186 
187  /* Encoder short version string */
188  memset(version, 0, sizeof(version));
189  avio_read(s->pb, version, 9);
190 
191  /* Info Tag revision + VBR method */
192  avio_r8(s->pb);
193 
194  /* Lowpass filter value */
195  avio_r8(s->pb);
196 
197  /* ReplayGain peak */
198  v = avio_rb32(s->pb);
199  peak = av_rescale(v, 100000, 1 << 23);
200 
201  /* Radio ReplayGain */
202  v = avio_rb16(s->pb);
203 
204  if (MIDDLE_BITS(v, 13, 15) == 1) {
205  r_gain = MIDDLE_BITS(v, 0, 8) * 10000;
206 
207  if (v & (1 << 9))
208  r_gain *= -1;
209  }
210 
211  /* Audiophile ReplayGain */
212  v = avio_rb16(s->pb);
213 
214  if (MIDDLE_BITS(v, 13, 15) == 2) {
215  a_gain = MIDDLE_BITS(v, 0, 8) * 10000;
216 
217  if (v & (1 << 9))
218  a_gain *= -1;
219  }
220 
221  /* Encoding flags + ATH Type */
222  avio_r8(s->pb);
223 
224  /* if ABR {specified bitrate} else {minimal bitrate} */
225  avio_r8(s->pb);
226 
227  /* Encoder delays */
228  v= avio_rb24(s->pb);
229  if(AV_RB32(version) == MKBETAG('L', 'A', 'M', 'E')
230  || AV_RB32(version) == MKBETAG('L', 'a', 'v', 'f')
231  || AV_RB32(version) == MKBETAG('L', 'a', 'v', 'c')
232  ) {
233 
234  mp3->start_pad = v>>12;
235  mp3-> end_pad = v&4095;
236  st->start_skip_samples = mp3->start_pad + 528 + 1;
237  if (mp3->frames) {
238  st->first_discard_sample = -mp3->end_pad + 528 + 1 + mp3->frames * (int64_t)spf;
239  st->last_discard_sample = mp3->frames * (int64_t)spf;
240  }
241  if (!st->start_time)
242  st->start_time = av_rescale_q(st->start_skip_samples,
243  (AVRational){1, c->sample_rate},
244  st->time_base);
245  av_log(s, AV_LOG_DEBUG, "pad %d %d\n", mp3->start_pad, mp3-> end_pad);
246  }
247 
248  /* Misc */
249  avio_r8(s->pb);
250 
251  /* MP3 gain */
252  avio_r8(s->pb);
253 
254  /* Preset and surround info */
255  avio_rb16(s->pb);
256 
257  /* Music length */
258  avio_rb32(s->pb);
259 
260  /* Music CRC */
261  avio_rb16(s->pb);
262 
263  /* Info Tag CRC */
264  crc = ffio_get_checksum(s->pb);
265  v = avio_rb16(s->pb);
266 
267  if (v == crc) {
268  ff_replaygain_export_raw(st, r_gain, peak, a_gain, 0);
269  av_dict_set(&st->metadata, "encoder", version, 0);
270  }
271 }
272 
273 static void mp3_parse_vbri_tag(AVFormatContext *s, AVStream *st, int64_t base)
274 {
275  uint32_t v;
276  MP3DecContext *mp3 = s->priv_data;
277 
278  /* Check for VBRI tag (always 32 bytes after end of mpegaudio header) */
279  avio_seek(s->pb, base + 4 + 32, SEEK_SET);
280  v = avio_rb32(s->pb);
281  if (v == MKBETAG('V', 'B', 'R', 'I')) {
282  /* Check tag version */
283  if (avio_rb16(s->pb) == 1) {
284  /* skip delay and quality */
285  avio_skip(s->pb, 4);
286  mp3->header_filesize = avio_rb32(s->pb);
287  mp3->frames = avio_rb32(s->pb);
288  }
289  }
290 }
291 
292 /**
293  * Try to find Xing/Info/VBRI tags and compute duration from info therein
294  */
295 static int mp3_parse_vbr_tags(AVFormatContext *s, AVStream *st, int64_t base)
296 {
297  uint32_t v, spf;
299  int vbrtag_size = 0;
300  MP3DecContext *mp3 = s->priv_data;
301 
303 
304  v = avio_rb32(s->pb);
305  if(ff_mpa_check_header(v) < 0)
306  return -1;
307 
308  if (avpriv_mpegaudio_decode_header(&c, v) == 0)
309  vbrtag_size = c.frame_size;
310  if(c.layer != 3)
311  return -1;
312 
313  spf = c.lsf ? 576 : 1152; /* Samples per frame, layer 3 */
314 
315  mp3->frames = 0;
316  mp3->header_filesize = 0;
317 
318  mp3_parse_info_tag(s, st, &c, spf);
319  mp3_parse_vbri_tag(s, st, base);
320 
321  if (!mp3->frames && !mp3->header_filesize)
322  return -1;
323 
324  /* Skip the vbr tag frame */
325  avio_seek(s->pb, base + vbrtag_size, SEEK_SET);
326 
327  if (mp3->frames)
328  st->duration = av_rescale_q(mp3->frames, (AVRational){spf, c.sample_rate},
329  st->time_base);
330  if (mp3->header_filesize && mp3->frames && !mp3->is_cbr)
331  st->codec->bit_rate = av_rescale(mp3->header_filesize, 8 * c.sample_rate, mp3->frames * (int64_t)spf);
332 
333  return 0;
334 }
335 
337 {
338  MP3DecContext *mp3 = s->priv_data;
339  AVStream *st;
340  int64_t off;
341  int ret;
342  int i;
343 
344  if (mp3->usetoc < 0)
345  mp3->usetoc = (s->flags & AVFMT_FLAG_FAST_SEEK) ? 0 : 2;
346 
347  st = avformat_new_stream(s, NULL);
348  if (!st)
349  return AVERROR(ENOMEM);
350 
354  st->start_time = 0;
355 
356  // lcm of all mp3 sample rates
357  avpriv_set_pts_info(st, 64, 1, 14112000);
358 
359  s->pb->maxsize = -1;
360  off = avio_tell(s->pb);
361 
363  ff_id3v1_read(s);
364 
365  if(s->pb->seekable)
366  mp3->filesize = avio_size(s->pb);
367 
368  if (mp3_parse_vbr_tags(s, st, off) < 0)
369  avio_seek(s->pb, off, SEEK_SET);
370 
371  ret = ff_replaygain_export(st, s->metadata);
372  if (ret < 0)
373  return ret;
374 
375  off = avio_tell(s->pb);
376  for (i = 0; i < 64 * 1024; i++) {
377  if (!(i&1023))
378  ffio_ensure_seekback(s->pb, i + 1024 + 4);
379  if (check(s, off + i) >= 0) {
380  av_log(s, AV_LOG_INFO, "Skipping %d bytes of junk at %lld.\n", i, (long long)off);
381  avio_seek(s->pb, off + i, SEEK_SET);
382  break;
383  }
384  avio_seek(s->pb, off, SEEK_SET);
385  }
386 
387  // the seek index is relative to the end of the xing vbr headers
388  for (i = 0; i < st->nb_index_entries; i++)
389  st->index_entries[i].pos += avio_tell(s->pb);
390 
391  /* the parameters will be extracted from the compressed bitstream */
392  return 0;
393 }
394 
395 #define MP3_PACKET_SIZE 1024
396 
398 {
399  MP3DecContext *mp3 = s->priv_data;
400  int ret, size;
401  int64_t pos;
402 
403  size= MP3_PACKET_SIZE;
404  pos = avio_tell(s->pb);
405  if(mp3->filesize > ID3v1_TAG_SIZE && pos < mp3->filesize)
406  size= FFMIN(size, mp3->filesize - pos);
407 
408  ret= av_get_packet(s->pb, pkt, size);
409  if (ret <= 0) {
410  if(ret<0)
411  return ret;
412  return AVERROR_EOF;
413  }
414 
415  pkt->flags &= ~AV_PKT_FLAG_CORRUPT;
416  pkt->stream_index = 0;
417 
418  if (ret >= ID3v1_TAG_SIZE &&
419  memcmp(&pkt->data[ret - ID3v1_TAG_SIZE], "TAG", 3) == 0)
420  ret -= ID3v1_TAG_SIZE;
421 
422  /* note: we need to modify the packet size here to handle the last
423  packet */
424  pkt->size = ret;
425  return ret;
426 }
427 
428 static int check(AVFormatContext *s, int64_t pos)
429 {
430  int64_t ret = avio_seek(s->pb, pos, SEEK_SET);
431  unsigned header;
432  MPADecodeHeader sd;
433  if (ret < 0)
434  return ret;
435  header = avio_rb32(s->pb);
436  if (ff_mpa_check_header(header) < 0)
437  return -1;
438  if (avpriv_mpegaudio_decode_header(&sd, header) == 1)
439  return -1;
440  return sd.frame_size;
441 }
442 
443 static int mp3_seek(AVFormatContext *s, int stream_index, int64_t timestamp,
444  int flags)
445 {
446  MP3DecContext *mp3 = s->priv_data;
447  AVIndexEntry *ie, ie1;
448  AVStream *st = s->streams[0];
449  int64_t ret = av_index_search_timestamp(st, timestamp, flags);
450  int i, j;
451  int dir = (flags&AVSEEK_FLAG_BACKWARD) ? -1 : 1;
452  int64_t best_pos;
453  int best_score;
454 
455  if (mp3->usetoc == 2)
456  return -1; // generic index code
457 
458  if ( mp3->is_cbr
459  && (mp3->usetoc == 0 || !mp3->xing_toc)
460  && st->duration > 0
461  && mp3->header_filesize > s->internal->data_offset
462  && mp3->frames) {
463  ie = &ie1;
464  timestamp = av_clip64(timestamp, 0, st->duration);
465  ie->timestamp = timestamp;
466  ie->pos = av_rescale(timestamp, mp3->header_filesize, st->duration) + s->internal->data_offset;
467  } else if (mp3->xing_toc) {
468  if (ret < 0)
469  return ret;
470 
471  ie = &st->index_entries[ret];
472  } else {
473  return -1;
474  }
475 
476  avio_seek(s->pb, FFMAX(ie->pos - 4096, 0), SEEK_SET);
477  ret = avio_seek(s->pb, ie->pos, SEEK_SET);
478  if (ret < 0)
479  return ret;
480 
481 #define MIN_VALID 3
482  best_pos = ie->pos;
483  best_score = 999;
484  for(i=0; i<4096; i++) {
485  int64_t pos = ie->pos + (dir > 0 ? i - 1024 : -i);
486  int64_t candidate = -1;
487  int score = 999;
488 
489  if (pos < 0)
490  continue;
491 
492  for(j=0; j<MIN_VALID; j++) {
493  ret = check(s, pos);
494  if(ret < 0)
495  break;
496  if ((ie->pos - pos)*dir <= 0 && abs(MIN_VALID/2-j) < score) {
497  candidate = pos;
498  score = abs(MIN_VALID/2-j);
499  }
500  pos += ret;
501  }
502  if (best_score > score && j == MIN_VALID) {
503  best_pos = candidate;
504  best_score = score;
505  if(score == 0)
506  break;
507  }
508  }
509 
510  ret = avio_seek(s->pb, best_pos, SEEK_SET);
511  if (ret < 0)
512  return ret;
513 
514  if (mp3->is_cbr && ie == &ie1) {
515  int frame_duration = av_rescale(st->duration, 1, mp3->frames);
516  ie1.timestamp = frame_duration * av_rescale(best_pos - s->internal->data_offset, mp3->frames, mp3->header_filesize);
517  }
518 
519  ff_update_cur_dts(s, st, ie->timestamp);
520  return 0;
521 }
522 
523 static const AVOption options[] = {
524  { "usetoc", "use table of contents", offsetof(MP3DecContext, usetoc), AV_OPT_TYPE_INT, {.i64 = -1}, -1, 2, AV_OPT_FLAG_DECODING_PARAM},
525  { NULL },
526 };
527 
528 static const AVClass demuxer_class = {
529  .class_name = "mp3",
530  .item_name = av_default_item_name,
531  .option = options,
532  .version = LIBAVUTIL_VERSION_INT,
533  .category = AV_CLASS_CATEGORY_DEMUXER,
534 };
535 
537  .name = "mp3",
538  .long_name = NULL_IF_CONFIG_SMALL("MP2/3 (MPEG audio layer 2/3)"),
539  .read_probe = mp3_read_probe,
540  .read_header = mp3_read_header,
541  .read_packet = mp3_read_packet,
542  .read_seek = mp3_seek,
543  .priv_data_size = sizeof(MP3DecContext),
545  .extensions = "mp2,mp3,m2a,mpa", /* XXX: use probe */
546  .priv_class = &demuxer_class,
547 };
#define AVSEEK_FLAG_BACKWARD
Definition: avformat.h:2266
#define NULL
Definition: coverity.c:32
float v
const char * s
Definition: avisynth_c.h:631
int64_t avio_size(AVIOContext *s)
Get the filesize.
Definition: aviobuf.c:281
AVOption.
Definition: opt.h:255
int av_add_index_entry(AVStream *st, int64_t pos, int64_t timestamp, int size, int distance, int flags)
Add an index entry into a sorted list.
Definition: utils.c:1742
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
#define LIBAVUTIL_VERSION_INT
Definition: version.h:62
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:4006
int64_t pos
Definition: avformat.h:784
int64_t data_offset
offset of the first packet
Definition: internal.h:66
void ff_id3v1_read(AVFormatContext *s)
Read an ID3v1 tag.
Definition: id3v1.c:235
int size
Definition: avcodec.h:1163
const char * b
Definition: vf_curves.c:109
#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:203
AVIndexEntry * index_entries
Only used if the format does not support seeking natively.
Definition: avformat.h:1046
AVFormatInternal * internal
An opaque field for libavformat internal usage.
Definition: avformat.h:1695
static void read_xing_toc(AVFormatContext *s, int64_t filesize, int64_t duration)
Definition: mp3dec.c:111
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:276
int version
Definition: avisynth_c.h:629
static AVPacket pkt
unsigned int avio_rb16(AVIOContext *s)
Definition: aviobuf.c:674
#define PROBE_BUF_MAX
Definition: internal.h:32
int64_t maxsize
max filesize, used to limit allocations This field is internal to libavformat and access from outside...
Definition: avio.h:166
unsigned frames
Definition: mp3dec.c:52
static int check(AVFormatContext *s, int64_t pos)
Definition: mp3dec.c:428
Format I/O context.
Definition: avformat.h:1272
void ff_update_cur_dts(AVFormatContext *s, AVStream *ref_st, int64_t timestamp)
Update cur_dts of all streams based on the given timestamp and AVStream.
Definition: utils.c:1656
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:72
Public dictionary API.
static int mp3_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: mp3dec.c:397
uint8_t
int usetoc
Definition: mp3dec.c:51
#define XING_FLAG_SIZE
Definition: mp3dec.c:39
float delta
AVOptions.
unsigned int avio_rb32(AVIOContext *s)
Definition: aviobuf.c:689
static int mp3_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
Definition: mp3dec.c:443
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:67
enum AVStreamParseType need_parsing
Definition: avformat.h:1035
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:3672
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_RB32
Definition: bytestream.h:85
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1340
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:39
int flags
Flags modifying the (de)muxer behaviour.
Definition: avformat.h:1383
uint8_t * data
Definition: avcodec.h:1162
int avpriv_mpegaudio_decode_header(MPADecodeHeader *s, uint32_t header)
static const uint8_t xing_offtbl[2][2]
Definition: mp3enc.c:124
#define AVERROR_EOF
End of file.
Definition: error.h:55
int av_get_packet(AVIOContext *s, AVPacket *pkt, int size)
Allocate and read the payload of a packet and initialize its fields with default values.
Definition: utils.c:241
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:365
static const uint8_t header[24]
Definition: sdr2.c:67
static int64_t duration
Definition: ffplay.c:321
int ff_replaygain_export(AVStream *st, AVDictionary *metadata)
Parse replaygain tags and export them as per-stream side data.
Definition: replaygain.c:91
full parsing and repack with timestamp and position generation by parser for raw this assumes that ea...
Definition: avformat.h:778
#define av_log(a,...)
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:537
int64_t filesize
Definition: mp3dec.c:47
int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq)
Rescale a 64-bit integer by 2 rational numbers.
Definition: mathematics.c:140
#define AVINDEX_KEYFRAME
Definition: avformat.h:791
AVDictionary * metadata
Metadata that applies to the whole file.
Definition: avformat.h:1482
int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags)
Get the index for a specific timestamp.
Definition: utils.c:1784
av_default_item_name
#define AVERROR(e)
Definition: error.h:43
int64_t timestamp
Timestamp in AVStream.time_base units, preferably the time from which on correctly decoded frames are...
Definition: avformat.h:785
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:175
static int mp3_read_header(AVFormatContext *s)
Definition: mp3dec.c:336
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:197
preferred ID for decoding MPEG audio layer 1, 2 or 3
Definition: avcodec.h:421
static int ff_mpa_check_header(uint32_t header)
#define FFMAX(a, b)
Definition: common.h:64
Libavcodec external API header.
int flags
A combination of AV_PKT_FLAG values.
Definition: avcodec.h:1168
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:528
int avpriv_mpa_decode_header(AVCodecContext *avctx, uint32_t head, int *sample_rate, int *channels, int *frame_size, int *bit_rate)
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:861
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:451
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:450
void ffio_init_checksum(AVIOContext *s, unsigned long(*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len), unsigned long checksum)
Definition: aviobuf.c:516
int seekable
A combination of AVIO_SEEKABLE_ flags or 0 when the stream is not seekable.
Definition: avio.h:160
unsigned int avio_rb24(AVIOContext *s)
Definition: aviobuf.c:682
int64_t av_rescale(int64_t a, int64_t b, int64_t c)
Rescale a 64-bit integer with rounding to nearest.
Definition: mathematics.c:127
#define MP3_PACKET_SIZE
Definition: mp3dec.c:395
#define FFMIN(a, b)
Definition: common.h:66
AVCodecContext * avcodec_alloc_context3(const AVCodec *codec)
Allocate an AVCodecContext and set its fields to default values.
Definition: options.c:147
ret
Definition: avfilter.c:974
int end_pad
Definition: mp3dec.c:50
static void mp3_parse_info_tag(AVFormatContext *s, AVStream *st, MPADecodeHeader *c, uint32_t spf)
Definition: mp3dec.c:135
int32_t
int xing_toc
Definition: mp3dec.c:48
unsigned long ff_crcA001_update(unsigned long checksum, const uint8_t *buf, unsigned int len)
Definition: aviobuf.c:502
static void mp3_parse_vbri_tag(AVFormatContext *s, AVStream *st, int64_t base)
Definition: mp3dec.c:273
#define MIN_VALID
Stream structure.
Definition: avformat.h:842
static int mp3_read_probe(AVProbeData *p)
Definition: mp3dec.c:61
#define AV_LOG_INFO
Standard information.
Definition: log.h:187
enum AVMediaType codec_type
Definition: avcodec.h:1249
void avcodec_free_context(AVCodecContext **avctx)
Free the codec context and everything associated with it and write NULL to the provided pointer...
Definition: options.c:162
enum AVCodecID codec_id
Definition: avcodec.h:1258
AVIOContext * pb
I/O context.
Definition: avformat.h:1314
main external API structure.
Definition: avcodec.h:1241
#define XING_FLAG_FRAMES
Definition: mp3dec.c:38
void * buf
Definition: avisynth_c.h:553
int av_dict_set(AVDictionary **pm, const char *key, const char *value, int flags)
Set the given entry in *pm, overwriting an existing entry.
Definition: dict.c:69
int nb_index_entries
Definition: avformat.h:1048
Describe the class of an AVClass context structure.
Definition: log.h:67
static const AVOption options[]
Definition: mp3dec.c:523
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:473
rational number numerator/denominator
Definition: rational.h:43
#define AV_OPT_FLAG_DECODING_PARAM
a generic parameter which can be set by the user for demuxing or decoding
Definition: opt.h:286
#define XING_FLAC_QSCALE
Definition: mp3dec.c:41
unsigned long ffio_get_checksum(AVIOContext *s)
Definition: aviobuf.c:508
#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 flags
Definition: cpu.c:47
int ffio_ensure_seekback(AVIOContext *s, int64_t buf_size)
Ensures that the requested seekback buffer size will be available.
Definition: aviobuf.c:809
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:901
MPEG Audio header decoder.
int is_cbr
Definition: mp3dec.c:54
Main libavformat public API header.
unsigned header_filesize
Definition: mp3dec.c:53
static const AVClass demuxer_class
Definition: mp3dec.c:528
int ff_id3v2_match(const uint8_t *buf, const char *magic)
Detect ID3v2 Header.
Definition: id3v2.c:141
int ff_replaygain_export_raw(AVStream *st, int32_t tg, uint32_t tp, int32_t ag, uint32_t ap)
Export already decoded replaygain values as per-stream side data.
Definition: replaygain.c:70
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base...
Definition: avformat.h:894
AVInputFormat ff_mp3_demuxer
Definition: mp3dec.c:536
static double c[64]
#define AV_PKT_FLAG_CORRUPT
The packet content is corrupted.
Definition: avcodec.h:1209
#define MKBETAG(a, b, c, d)
Definition: common.h:316
#define XING_FLAG_TOC
Definition: mp3dec.c:40
#define MIDDLE_BITS(k, m, n)
#define AVFMT_FLAG_FAST_SEEK
Enable fast, but inaccurate seeks for some formats.
Definition: avformat.h:1405
int ff_id3v2_tag_len(const uint8_t *buf)
Get the length of an ID3v2 tag.
Definition: id3v2.c:154
void * priv_data
Format private data.
Definition: avformat.h:1300
#define XING_TOC_COUNT
Definition: mp3dec.c:43
static int mp3_parse_vbr_tags(AVFormatContext *s, AVStream *st, int64_t base)
Try to find Xing/Info/VBRI tags and compute duration from info therein.
Definition: mp3dec.c:295
#define ID3v1_TAG_SIZE
Definition: id3v1.h:27
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:628
#define AV_DICT_IGNORE_SUFFIX
Return first entry in a dictionary whose first part corresponds to the search key, ignoring the suffix of the found key string.
Definition: dict.h:72
int start_pad
Definition: mp3dec.c:49
int stream_index
Definition: avcodec.h:1164
int dummy
Definition: motion-test.c:64
float min
This structure stores compressed data.
Definition: avcodec.h:1139