FFmpeg  4.3.9
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 
46 typedef struct {
47  AVClass *class;
49  int xing_toc;
50  int start_pad;
51  int end_pad;
52  int usetoc;
53  unsigned frames; /* Total number of frames in file */
54  unsigned header_filesize; /* Total number of bytes in the stream */
55  int is_cbr;
57 
58 enum CheckRet {
61 };
62 
63 static int check(AVIOContext *pb, int64_t pos, uint32_t *header);
64 
65 /* mp3 read */
66 
67 static int mp3_read_probe(const AVProbeData *p)
68 {
69  int max_frames, first_frames = 0;
70  int whole_used = 0;
71  int frames, ret;
72  int framesizes, max_framesizes;
73  uint32_t header;
74  const uint8_t *buf, *buf0, *buf2, *buf3, *end;
75 
76  buf0 = p->buf;
77  end = p->buf + p->buf_size - sizeof(uint32_t);
78  while (buf0 < end && !*buf0)
79  buf0++;
80 
81  max_frames = 0;
82  max_framesizes = 0;
83  buf = buf0;
84 
85  for (; buf < end; buf = buf2+1) {
86  buf2 = buf;
87  for (framesizes = frames = 0; buf2 < end; frames++) {
89  int header_emu = 0;
90  int available;
91 
92  header = AV_RB32(buf2);
93  ret = avpriv_mpegaudio_decode_header(&h, header);
94  if (ret != 0)
95  break;
96 
97  available = FFMIN(h.frame_size, end - buf2);
98  for (buf3 = buf2 + 4; buf3 < buf2 + available; buf3++) {
99  uint32_t next_sync = AV_RB32(buf3);
100  header_emu += (next_sync & MP3_MASK) == (header & MP3_MASK);
101  }
102  if (header_emu > 2)
103  break;
104  framesizes += h.frame_size;
105  if (available < h.frame_size) {
106  frames++;
107  break;
108  }
109  buf2 += h.frame_size;
110  }
111  max_frames = FFMAX(max_frames, frames);
112  max_framesizes = FFMAX(max_framesizes, framesizes);
113  if (buf == buf0) {
114  first_frames= frames;
115  if (buf2 == end + sizeof(uint32_t))
116  whole_used = 1;
117  }
118  }
119  // keep this in sync with ac3 probe, both need to avoid
120  // issues with MPEG-files!
121  if (first_frames>=7) return AVPROBE_SCORE_EXTENSION + 1;
122  else if (max_frames>200 && p->buf_size < 2*max_framesizes)return AVPROBE_SCORE_EXTENSION;
123  else if (max_frames>=4 && p->buf_size < 2*max_framesizes) return AVPROBE_SCORE_EXTENSION / 2;
124  else if (ff_id3v2_match(buf0, ID3v2_DEFAULT_MAGIC) && 2*ff_id3v2_tag_len(buf0) >= p->buf_size)
126  else if (first_frames > 1 && whole_used) return 5;
127  else if (max_frames>=1 && p->buf_size < 10*max_framesizes) return 1;
128  else return 0;
129  //mpegps_mp3_unrecognized_format.mpg has max_frames=3
130 }
131 
133 {
134  int i;
135  MP3DecContext *mp3 = s->priv_data;
136  int fast_seek = s->flags & AVFMT_FLAG_FAST_SEEK;
137  int fill_index = (mp3->usetoc || fast_seek) && duration > 0;
138 
139  if (!filesize &&
140  (filesize = avio_size(s->pb)) <= 0) {
141  av_log(s, AV_LOG_WARNING, "Cannot determine file size, skipping TOC table.\n");
142  fill_index = 0;
143  filesize = 0;
144  }
145 
146  for (i = 0; i < XING_TOC_COUNT; i++) {
147  uint8_t b = avio_r8(s->pb);
148  if (fill_index)
150  av_rescale(b, filesize, 256),
151  av_rescale(i, duration, XING_TOC_COUNT),
152  0, 0, AVINDEX_KEYFRAME);
153  }
154  if (fill_index)
155  mp3->xing_toc = 1;
156 }
157 
159  MPADecodeHeader *c, uint32_t spf)
160 {
161 #define LAST_BITS(k, n) ((k) & ((1 << (n)) - 1))
162 #define MIDDLE_BITS(k, m, n) LAST_BITS((k) >> (m), ((n) - (m) + 1))
163 
164  uint16_t crc;
165  uint32_t v;
166 
167  char version[10];
168 
169  uint32_t peak = 0;
170  int32_t r_gain = INT32_MIN, a_gain = INT32_MIN;
171 
172  MP3DecContext *mp3 = s->priv_data;
173  static const int64_t xing_offtbl[2][2] = {{32, 17}, {17,9}};
174  uint64_t fsize = avio_size(s->pb);
175  fsize = fsize >= avio_tell(s->pb) ? fsize - avio_tell(s->pb) : 0;
176 
177  /* Check for Xing / Info tag */
178  avio_skip(s->pb, xing_offtbl[c->lsf == 1][c->nb_channels == 1]);
179  v = avio_rb32(s->pb);
180  mp3->is_cbr = v == MKBETAG('I', 'n', 'f', 'o');
181  if (v != MKBETAG('X', 'i', 'n', 'g') && !mp3->is_cbr)
182  return;
183 
184  v = avio_rb32(s->pb);
185  if (v & XING_FLAG_FRAMES)
186  mp3->frames = avio_rb32(s->pb);
187  if (v & XING_FLAG_SIZE)
188  mp3->header_filesize = avio_rb32(s->pb);
189  if (fsize && mp3->header_filesize) {
190  uint64_t min, delta;
191  min = FFMIN(fsize, mp3->header_filesize);
192  delta = FFMAX(fsize, mp3->header_filesize) - min;
193  if (fsize > mp3->header_filesize && delta > min >> 4) {
194  mp3->frames = 0;
196  "invalid concatenated file detected - using bitrate for duration\n");
197  } else if (delta > min >> 4) {
199  "filesize and duration do not match (growing file?)\n");
200  }
201  }
202  if (v & XING_FLAG_TOC)
204  (AVRational){spf, c->sample_rate},
205  st->time_base));
206  /* VBR quality */
207  if (v & XING_FLAC_QSCALE)
208  avio_rb32(s->pb);
209 
210  /* Encoder short version string */
211  memset(version, 0, sizeof(version));
212  avio_read(s->pb, version, 9);
213 
214  /* Info Tag revision + VBR method */
215  avio_r8(s->pb);
216 
217  /* Lowpass filter value */
218  avio_r8(s->pb);
219 
220  /* ReplayGain peak */
221  v = avio_rb32(s->pb);
222  peak = av_rescale(v, 100000, 1 << 23);
223 
224  /* Radio ReplayGain */
225  v = avio_rb16(s->pb);
226 
227  if (MIDDLE_BITS(v, 13, 15) == 1) {
228  r_gain = MIDDLE_BITS(v, 0, 8) * 10000;
229 
230  if (v & (1 << 9))
231  r_gain *= -1;
232  }
233 
234  /* Audiophile ReplayGain */
235  v = avio_rb16(s->pb);
236 
237  if (MIDDLE_BITS(v, 13, 15) == 2) {
238  a_gain = MIDDLE_BITS(v, 0, 8) * 10000;
239 
240  if (v & (1 << 9))
241  a_gain *= -1;
242  }
243 
244  /* Encoding flags + ATH Type */
245  avio_r8(s->pb);
246 
247  /* if ABR {specified bitrate} else {minimal bitrate} */
248  avio_r8(s->pb);
249 
250  /* Encoder delays */
251  v = avio_rb24(s->pb);
252  if (AV_RB32(version) == MKBETAG('L', 'A', 'M', 'E')
253  || AV_RB32(version) == MKBETAG('L', 'a', 'v', 'f')
254  || AV_RB32(version) == MKBETAG('L', 'a', 'v', 'c')
255  ) {
256 
257  mp3->start_pad = v>>12;
258  mp3-> end_pad = v&4095;
259  st->start_skip_samples = mp3->start_pad + 528 + 1;
260  if (mp3->frames) {
261  st->first_discard_sample = -mp3->end_pad + 528 + 1 + mp3->frames * (int64_t)spf;
262  st->last_discard_sample = mp3->frames * (int64_t)spf;
263  }
264  if (!st->start_time)
266  (AVRational){1, c->sample_rate},
267  st->time_base);
268  av_log(s, AV_LOG_DEBUG, "pad %d %d\n", mp3->start_pad, mp3-> end_pad);
269  }
270 
271  /* Misc */
272  avio_r8(s->pb);
273 
274  /* MP3 gain */
275  avio_r8(s->pb);
276 
277  /* Preset and surround info */
278  avio_rb16(s->pb);
279 
280  /* Music length */
281  avio_rb32(s->pb);
282 
283  /* Music CRC */
284  avio_rb16(s->pb);
285 
286  /* Info Tag CRC */
287  crc = ffio_get_checksum(s->pb);
288  v = avio_rb16(s->pb);
289 
290  if (v == crc) {
291  ff_replaygain_export_raw(st, r_gain, peak, a_gain, 0);
292  av_dict_set(&st->metadata, "encoder", version, 0);
293  }
294 }
295 
297 {
298  uint32_t v;
299  MP3DecContext *mp3 = s->priv_data;
300 
301  /* Check for VBRI tag (always 32 bytes after end of mpegaudio header) */
302  avio_seek(s->pb, base + 4 + 32, SEEK_SET);
303  v = avio_rb32(s->pb);
304  if (v == MKBETAG('V', 'B', 'R', 'I')) {
305  /* Check tag version */
306  if (avio_rb16(s->pb) == 1) {
307  /* skip delay and quality */
308  avio_skip(s->pb, 4);
309  mp3->header_filesize = avio_rb32(s->pb);
310  mp3->frames = avio_rb32(s->pb);
311  }
312  }
313 }
314 
315 /**
316  * Try to find Xing/Info/VBRI tags and compute duration from info therein
317  */
319 {
320  uint32_t v, spf;
322  int vbrtag_size = 0;
323  MP3DecContext *mp3 = s->priv_data;
324  int ret;
325 
327 
328  v = avio_rb32(s->pb);
329 
330  ret = avpriv_mpegaudio_decode_header(&c, v);
331  if (ret < 0)
332  return ret;
333  else if (ret == 0)
334  vbrtag_size = c.frame_size;
335  if (c.layer != 3)
336  return -1;
337 
338  spf = c.lsf ? 576 : 1152; /* Samples per frame, layer 3 */
339 
340  mp3->frames = 0;
341  mp3->header_filesize = 0;
342 
343  mp3_parse_info_tag(s, st, &c, spf);
344  mp3_parse_vbri_tag(s, st, base);
345 
346  if (!mp3->frames && !mp3->header_filesize)
347  return -1;
348 
349  /* Skip the vbr tag frame */
350  avio_seek(s->pb, base + vbrtag_size, SEEK_SET);
351 
352  if (mp3->frames)
353  st->duration = av_rescale_q(mp3->frames, (AVRational){spf, c.sample_rate},
354  st->time_base);
355  if (mp3->header_filesize && mp3->frames && !mp3->is_cbr)
356  st->codecpar->bit_rate = av_rescale(mp3->header_filesize, 8 * c.sample_rate, mp3->frames * (int64_t)spf);
357 
358  return 0;
359 }
360 
362 {
363  MP3DecContext *mp3 = s->priv_data;
364  AVStream *st;
365  int64_t off;
366  int ret;
367  int i;
368 
369  s->metadata = s->internal->id3v2_meta;
370  s->internal->id3v2_meta = NULL;
371 
372  st = avformat_new_stream(s, NULL);
373  if (!st)
374  return AVERROR(ENOMEM);
375 
379  st->start_time = 0;
380 
381  // lcm of all mp3 sample rates
382  avpriv_set_pts_info(st, 64, 1, 14112000);
383 
384  s->pb->maxsize = -1;
385  off = avio_tell(s->pb);
386 
388  ff_id3v1_read(s);
389 
390  if (s->pb->seekable & AVIO_SEEKABLE_NORMAL)
391  mp3->filesize = avio_size(s->pb);
392 
393  if (mp3_parse_vbr_tags(s, st, off) < 0)
394  avio_seek(s->pb, off, SEEK_SET);
395 
396  ret = ff_replaygain_export(st, s->metadata);
397  if (ret < 0)
398  return ret;
399 
400  off = avio_tell(s->pb);
401  for (i = 0; i < 64 * 1024; i++) {
402  uint32_t header, header2;
403  int frame_size;
404  if (!(i&1023))
405  ffio_ensure_seekback(s->pb, i + 1024 + 4);
406  frame_size = check(s->pb, off + i, &header);
407  if (frame_size > 0) {
408  ret = avio_seek(s->pb, off, SEEK_SET);
409  if (ret < 0)
410  return ret;
411  ffio_ensure_seekback(s->pb, i + 1024 + frame_size + 4);
412  ret = check(s->pb, off + i + frame_size, &header2);
413  if (ret >= 0 &&
414  (header & MP3_MASK) == (header2 & MP3_MASK))
415  {
416  av_log(s, i > 0 ? AV_LOG_INFO : AV_LOG_VERBOSE, "Skipping %d bytes of junk at %"PRId64".\n", i, off);
417  ret = avio_seek(s->pb, off + i, SEEK_SET);
418  if (ret < 0)
419  return ret;
420  break;
421  } else if (ret == CHECK_SEEK_FAILED) {
422  av_log(s, AV_LOG_ERROR, "Invalid frame size (%d): Could not seek to %"PRId64".\n", frame_size, off + i + frame_size);
423  return AVERROR(EINVAL);
424  }
425  } else if (frame_size == CHECK_SEEK_FAILED) {
426  av_log(s, AV_LOG_ERROR, "Failed to read frame size: Could not seek to %"PRId64".\n", (int64_t) (i + 1024 + frame_size + 4));
427  return AVERROR(EINVAL);
428  }
429  ret = avio_seek(s->pb, off, SEEK_SET);
430  if (ret < 0)
431  return ret;
432  }
433 
434  // the seek index is relative to the end of the xing vbr headers
435  for (i = 0; i < st->nb_index_entries; i++)
436  st->index_entries[i].pos += avio_tell(s->pb);
437 
438  /* the parameters will be extracted from the compressed bitstream */
439  return 0;
440 }
441 
442 #define MP3_PACKET_SIZE 1024
443 
445 {
446  MP3DecContext *mp3 = s->priv_data;
447  int ret, size;
448  int64_t pos;
449 
450  size = MP3_PACKET_SIZE;
451  pos = avio_tell(s->pb);
452  if (mp3->filesize > ID3v1_TAG_SIZE && pos < mp3->filesize)
453  size= FFMIN(size, mp3->filesize - pos);
454 
455  ret = av_get_packet(s->pb, pkt, size);
456  if (ret <= 0) {
457  if(ret<0)
458  return ret;
459  return AVERROR_EOF;
460  }
461 
462  pkt->flags &= ~AV_PKT_FLAG_CORRUPT;
463  pkt->stream_index = 0;
464 
465  return ret;
466 }
467 
468 #define SEEK_WINDOW 4096
469 
470 static int check(AVIOContext *pb, int64_t pos, uint32_t *ret_header)
471 {
472  int64_t ret = avio_seek(pb, pos, SEEK_SET);
473  uint8_t header_buf[4];
474  unsigned header;
475  MPADecodeHeader sd;
476  if (ret < 0)
477  return CHECK_SEEK_FAILED;
478 
479  ret = avio_read(pb, &header_buf[0], 4);
480  /* We should always find four bytes for a valid mpa header. */
481  if (ret < 4)
482  return CHECK_SEEK_FAILED;
483 
484  header = AV_RB32(&header_buf[0]);
485  if (ff_mpa_check_header(header) < 0)
486  return CHECK_WRONG_HEADER;
487  if (avpriv_mpegaudio_decode_header(&sd, header) == 1)
488  return CHECK_WRONG_HEADER;
489 
490  if (ret_header)
491  *ret_header = header;
492  return sd.frame_size;
493 }
494 
495 static int64_t mp3_sync(AVFormatContext *s, int64_t target_pos, int flags)
496 {
497  int dir = (flags&AVSEEK_FLAG_BACKWARD) ? -1 : 1;
498  int64_t best_pos;
499  int best_score, i, j;
500  int64_t ret;
501 
502  avio_seek(s->pb, FFMAX(target_pos - SEEK_WINDOW, 0), SEEK_SET);
503  ret = avio_seek(s->pb, target_pos, SEEK_SET);
504  if (ret < 0)
505  return ret;
506 
507 #define MIN_VALID 3
508  best_pos = target_pos;
509  best_score = 999;
510  for (i = 0; i < SEEK_WINDOW; i++) {
511  int64_t pos = target_pos + (dir > 0 ? i - SEEK_WINDOW/4 : -i);
512  int64_t candidate = -1;
513  int score = 999;
514 
515  if (pos < 0)
516  continue;
517 
518  for (j = 0; j < MIN_VALID; j++) {
519  ret = check(s->pb, pos, NULL);
520  if (ret < 0) {
521  if (ret == CHECK_WRONG_HEADER) {
522  break;
523  } else if (ret == CHECK_SEEK_FAILED) {
524  av_log(s, AV_LOG_ERROR, "Could not seek to %"PRId64".\n", pos);
525  return AVERROR(EINVAL);
526  }
527  }
528  if ((target_pos - pos)*dir <= 0 && FFABS(MIN_VALID/2-j) < score) {
529  candidate = pos;
530  score = FFABS(MIN_VALID/2-j);
531  }
532  pos += ret;
533  }
534  if (best_score > score && j == MIN_VALID) {
535  best_pos = candidate;
536  best_score = score;
537  if(score == 0)
538  break;
539  }
540  }
541 
542  return avio_seek(s->pb, best_pos, SEEK_SET);
543 }
544 
545 static int mp3_seek(AVFormatContext *s, int stream_index, int64_t timestamp,
546  int flags)
547 {
548  MP3DecContext *mp3 = s->priv_data;
549  AVIndexEntry *ie, ie1;
550  AVStream *st = s->streams[0];
551  int64_t best_pos;
552  int fast_seek = s->flags & AVFMT_FLAG_FAST_SEEK;
553  int64_t filesize = mp3->header_filesize;
554 
555  if (filesize <= 0) {
556  int64_t size = avio_size(s->pb);
557  if (size > 0 && size > s->internal->data_offset)
558  filesize = size - s->internal->data_offset;
559  }
560 
561  if (mp3->xing_toc && (mp3->usetoc || (fast_seek && !mp3->is_cbr))) {
562  int64_t ret = av_index_search_timestamp(st, timestamp, flags);
563 
564  // NOTE: The MP3 TOC is not a precise lookup table. Accuracy is worse
565  // for bigger files.
566  av_log(s, AV_LOG_WARNING, "Using MP3 TOC to seek; may be imprecise.\n");
567 
568  if (ret < 0)
569  return ret;
570 
571  ie = &st->index_entries[ret];
572  } else if (fast_seek && st->duration > 0 && filesize > 0) {
573  if (!mp3->is_cbr)
574  av_log(s, AV_LOG_WARNING, "Using scaling to seek VBR MP3; may be imprecise.\n");
575 
576  ie = &ie1;
577  timestamp = av_clip64(timestamp, 0, st->duration);
578  ie->timestamp = timestamp;
579  ie->pos = av_rescale(timestamp, filesize, st->duration) + s->internal->data_offset;
580  } else {
581  return -1; // generic index code
582  }
583 
584  best_pos = mp3_sync(s, ie->pos, flags);
585  if (best_pos < 0)
586  return best_pos;
587 
588  if (mp3->is_cbr && ie == &ie1 && mp3->frames && mp3->header_filesize > 0) {
589  int frame_duration = av_rescale(st->duration, 1, mp3->frames);
590  ie1.timestamp = frame_duration * av_rescale(best_pos - s->internal->data_offset, mp3->frames, mp3->header_filesize);
591  }
592 
593  ff_update_cur_dts(s, st, ie->timestamp);
594  return 0;
595 }
596 
597 static const AVOption options[] = {
598  { "usetoc", "use table of contents", offsetof(MP3DecContext, usetoc), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, AV_OPT_FLAG_DECODING_PARAM},
599  { NULL },
600 };
601 
602 static const AVClass demuxer_class = {
603  .class_name = "mp3",
604  .item_name = av_default_item_name,
605  .option = options,
606  .version = LIBAVUTIL_VERSION_INT,
607  .category = AV_CLASS_CATEGORY_DEMUXER,
608 };
609 
611  .name = "mp3",
612  .long_name = NULL_IF_CONFIG_SMALL("MP2/3 (MPEG audio layer 2/3)"),
613  .read_probe = mp3_read_probe,
614  .read_header = mp3_read_header,
615  .read_packet = mp3_read_packet,
616  .read_seek = mp3_seek,
617  .priv_data_size = sizeof(MP3DecContext),
619  .extensions = "mp2,mp3,m2a,mpa", /* XXX: use probe */
620  .priv_class = &demuxer_class,
621 };
#define AVSEEK_FLAG_BACKWARD
Definition: avformat.h:2512
#define NULL
Definition: coverity.c:32
AVDictionary * id3v2_meta
ID3v2 tag useful for MP3 demuxing.
Definition: internal.h:139
Bytestream IO Context.
Definition: avio.h:161
int64_t avio_size(AVIOContext *s)
Get the filesize.
Definition: aviobuf.c:334
version
Definition: libkvazaar.c:292
int size
AVOption.
Definition: opt.h:246
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:2052
int64_t start_skip_samples
If not 0, the number of samples that should be skipped from the start of the stream (the samples are ...
Definition: avformat.h:1152
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
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
int64_t pos
Definition: avformat.h:805
#define MP3_MASK
int64_t data_offset
offset of the first packet
Definition: internal.h:80
int64_t first_discard_sample
If not 0, the first audio sample that should be discarded from the stream.
Definition: avformat.h:1160
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
void ff_id3v1_read(AVFormatContext *s)
Read an ID3v1 tag.
Definition: id3v1.c:279
const char * b
Definition: vf_curves.c:116
#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:241
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:235
AVIndexEntry * index_entries
Only used if the format does not support seeking natively.
Definition: avformat.h:1105
AVFormatInternal * internal
An opaque field for libavformat internal usage.
Definition: avformat.h:1804
static void read_xing_toc(AVFormatContext *s, int64_t filesize, int64_t duration)
Definition: mp3dec.c:132
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:329
static AVPacket pkt
unsigned int avio_rb16(AVIOContext *s)
Definition: aviobuf.c:763
#define PROBE_BUF_MAX
Definition: internal.h:34
int64_t maxsize
max filesize, used to limit allocations This field is internal to libavformat and access from outside...
Definition: avio.h:266
unsigned frames
Definition: mp3dec.c:53
uint8_t base
Definition: vp3data.h:202
Format I/O context.
Definition: avformat.h:1351
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:1966
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
CheckRet
Definition: mp3dec.c:58
Public dictionary API.
static int mp3_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: mp3dec.c:444
uint8_t
int usetoc
Definition: mp3dec.c:52
#define XING_FLAG_SIZE
Definition: mp3dec.c:39
float delta
AVOptions.
unsigned int avio_rb32(AVIOContext *s)
Definition: aviobuf.c:778
static int mp3_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
Definition: mp3dec.c:545
#define AV_RB32
Definition: intreadwrite.h:130
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:92
enum AVStreamParseType need_parsing
Definition: avformat.h:1094
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
int64_t duration
Definition: movenc.c:63
Public header for CRC hash function implementation.
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:40
int flags
Flags modifying the (de)muxer behaviour.
Definition: avformat.h:1482
int avpriv_mpegaudio_decode_header(MPADecodeHeader *s, uint32_t header)
static const uint8_t xing_offtbl[2][2]
Definition: mp3enc.c:137
#define AVERROR_EOF
End of file.
Definition: error.h:55
#define AV_LOG_VERBOSE
Detailed information.
Definition: log.h:192
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:307
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:557
static const uint8_t header[24]
Definition: sdr2.c:67
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:799
#define av_log(a,...)
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
int64_t filesize
Definition: mp3dec.c:48
int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq)
Rescale a 64-bit integer by 2 rational numbers.
Definition: mathematics.c:142
#define AVINDEX_KEYFRAME
Definition: avformat.h:812
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:269
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
AVDictionary * metadata
Metadata that applies to the whole file.
Definition: avformat.h:1591
int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags)
Get the index for a specific timestamp.
Definition: utils.c:2169
#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:806
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:188
static int mp3_read_header(AVFormatContext *s)
Definition: mp3dec.c:361
unsigned int pos
Definition: spdifenc.c:412
#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: codec_id.h:411
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
static int ff_mpa_check_header(uint32_t header)
#define FFMAX(a, b)
Definition: common.h:94
int flags
A combination of AV_PKT_FLAG values.
Definition: packet.h:361
static int mp3_read_probe(const AVProbeData *p)
Definition: mp3dec.c:67
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:616
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:444
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:443
#define SEEK_WINDOW
Definition: mp3dec.c:468
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:604
int seekable
A combination of AVIO_SEEKABLE_ flags or 0 when the stream is not seekable.
Definition: avio.h:260
unsigned int avio_rb24(AVIOContext *s)
Definition: aviobuf.c:771
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:129
#define MP3_PACKET_SIZE
Definition: mp3dec.c:442
#define FFMIN(a, b)
Definition: common.h:96
static int check(AVIOContext *pb, int64_t pos, uint32_t *header)
Definition: mp3dec.c:470
int end_pad
Definition: mp3dec.c:51
static void mp3_parse_info_tag(AVFormatContext *s, AVStream *st, MPADecodeHeader *c, uint32_t spf)
Definition: mp3dec.c:158
int32_t
#define FFABS(a)
Absolute value, Note, INT_MIN / INT64_MIN result in undefined behavior as they are not representable ...
Definition: common.h:72
static int64_t mp3_sync(AVFormatContext *s, int64_t target_pos, int flags)
Definition: mp3dec.c:495
#define s(width, name)
Definition: cbs_vp9.c:257
int xing_toc
Definition: mp3dec.c:49
AVDictionary * metadata
Definition: avformat.h:940
unsigned long ff_crcA001_update(unsigned long checksum, const uint8_t *buf, unsigned int len)
Definition: aviobuf.c:590
static void mp3_parse_vbri_tag(AVFormatContext *s, AVStream *st, int64_t base)
Definition: mp3dec.c:296
int frames
Definition: movenc.c:65
#define MIN_VALID
Stream structure.
Definition: avformat.h:876
#define AVIO_SEEKABLE_NORMAL
Seeking works like for a local file.
Definition: avio.h:40
#define AV_LOG_INFO
Standard information.
Definition: log.h:187
int frame_size
Definition: mxfenc.c:2137
Libavcodec external API header.
AVIOContext * pb
I/O context.
Definition: avformat.h:1393
long long int64_t
Definition: coverity.c:34
#define XING_FLAG_FRAMES
Definition: mp3dec.c:38
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:70
int nb_index_entries
Definition: avformat.h:1107
Describe the class of an AVClass context structure.
Definition: log.h:67
static const AVOption options[]
Definition: mp3dec.c:597
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:463
Rational number (pair of numerator and denominator).
Definition: rational.h:58
#define AV_OPT_FLAG_DECODING_PARAM
a generic parameter which can be set by the user for demuxing or decoding
Definition: opt.h:277
#define XING_FLAC_QSCALE
Definition: mp3dec.c:41
unsigned long ffio_get_checksum(AVIOContext *s)
Definition: aviobuf.c:596
#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
int ffio_ensure_seekback(AVIOContext *s, int64_t buf_size)
Ensures that the requested seekback buffer size will be available.
Definition: aviobuf.c:982
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:925
MPEG Audio header decoder.
int is_cbr
Definition: mp3dec.c:55
Main libavformat public API header.
unsigned header_filesize
Definition: mp3dec.c:54
static const AVClass demuxer_class
Definition: mp3dec.c:602
int ff_id3v2_match(const uint8_t *buf, const char *magic)
Detect ID3v2 Header.
Definition: id3v2.c:143
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:915
AVInputFormat ff_mp3_demuxer
Definition: mp3dec.c:610
static double c[64]
#define AV_PKT_FLAG_CORRUPT
The packet content is corrupted.
Definition: packet.h:389
#define MKBETAG(a, b, c, d)
Definition: common.h:407
#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:1508
int ff_id3v2_tag_len(const uint8_t *buf)
Get the length of an ID3v2 tag.
Definition: id3v2.c:156
void * priv_data
Format private data.
Definition: avformat.h:1379
#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:318
#define ID3v1_TAG_SIZE
Definition: id3v1.h:27
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:650
#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:70
int start_pad
Definition: mp3dec.c:50
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1023
static int64_t fsize(FILE *f)
Definition: audiomatch.c:28
int stream_index
Definition: packet.h:357
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented...
Definition: avformat.h:905
float min
This structure stores compressed data.
Definition: packet.h:332
int64_t last_discard_sample
The sample after last sample that is intended to be discarded after first_discard_sample.
Definition: avformat.h:1167