FFmpeg  4.4.4
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;
48  int64_t filesize;
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);
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 
132 static void read_xing_toc(AVFormatContext *s, int64_t filesize, int64_t duration)
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))) {
141  av_log(s, AV_LOG_WARNING, "Cannot determine file size, skipping TOC table.\n");
142  fill_index = 0;
143  }
144 
145  for (i = 0; i < XING_TOC_COUNT; i++) {
146  uint8_t b = avio_r8(s->pb);
147  if (fill_index)
148  av_add_index_entry(s->streams[0],
149  av_rescale(b, filesize, 256),
151  0, 0, AVINDEX_KEYFRAME);
152  }
153  if (fill_index)
154  mp3->xing_toc = 1;
155 }
156 
158  MPADecodeHeader *c, uint32_t spf)
159 {
160 #define LAST_BITS(k, n) ((k) & ((1 << (n)) - 1))
161 #define MIDDLE_BITS(k, m, n) LAST_BITS((k) >> (m), ((n) - (m) + 1))
162 
163  uint16_t crc;
164  uint32_t v;
165 
166  char version[10];
167 
168  uint32_t peak = 0;
169  int32_t r_gain = INT32_MIN, a_gain = INT32_MIN;
170 
171  MP3DecContext *mp3 = s->priv_data;
172  static const int64_t xing_offtbl[2][2] = {{32, 17}, {17,9}};
173  uint64_t fsize = avio_size(s->pb);
174  fsize = fsize >= avio_tell(s->pb) ? fsize - avio_tell(s->pb) : 0;
175 
176  /* Check for Xing / Info tag */
177  avio_skip(s->pb, xing_offtbl[c->lsf == 1][c->nb_channels == 1]);
178  v = avio_rb32(s->pb);
179  mp3->is_cbr = v == MKBETAG('I', 'n', 'f', 'o');
180  if (v != MKBETAG('X', 'i', 'n', 'g') && !mp3->is_cbr)
181  return;
182 
183  v = avio_rb32(s->pb);
184  if (v & XING_FLAG_FRAMES)
185  mp3->frames = avio_rb32(s->pb);
186  if (v & XING_FLAG_SIZE)
187  mp3->header_filesize = avio_rb32(s->pb);
188  if (fsize && mp3->header_filesize) {
189  uint64_t min, delta;
190  min = FFMIN(fsize, mp3->header_filesize);
191  delta = FFMAX(fsize, mp3->header_filesize) - min;
192  if (fsize > mp3->header_filesize && delta > min >> 4) {
193  mp3->frames = 0;
195  "invalid concatenated file detected - using bitrate for duration\n");
196  } else if (delta > min >> 4) {
198  "filesize and duration do not match (growing file?)\n");
199  }
200  }
201  if (v & XING_FLAG_TOC)
203  (AVRational){spf, c->sample_rate},
204  st->time_base));
205  /* VBR quality */
206  if (v & XING_FLAC_QSCALE)
207  avio_rb32(s->pb);
208 
209  /* Encoder short version string */
210  memset(version, 0, sizeof(version));
211  avio_read(s->pb, version, 9);
212 
213  /* Info Tag revision + VBR method */
214  avio_r8(s->pb);
215 
216  /* Lowpass filter value */
217  avio_r8(s->pb);
218 
219  /* ReplayGain peak */
220  v = avio_rb32(s->pb);
221  peak = av_rescale(v, 100000, 1 << 23);
222 
223  /* Radio ReplayGain */
224  v = avio_rb16(s->pb);
225 
226  if (MIDDLE_BITS(v, 13, 15) == 1) {
227  r_gain = MIDDLE_BITS(v, 0, 8) * 10000;
228 
229  if (v & (1 << 9))
230  r_gain *= -1;
231  }
232 
233  /* Audiophile ReplayGain */
234  v = avio_rb16(s->pb);
235 
236  if (MIDDLE_BITS(v, 13, 15) == 2) {
237  a_gain = MIDDLE_BITS(v, 0, 8) * 10000;
238 
239  if (v & (1 << 9))
240  a_gain *= -1;
241  }
242 
243  /* Encoding flags + ATH Type */
244  avio_r8(s->pb);
245 
246  /* if ABR {specified bitrate} else {minimal bitrate} */
247  avio_r8(s->pb);
248 
249  /* Encoder delays */
250  v = avio_rb24(s->pb);
251  if (AV_RB32(version) == MKBETAG('L', 'A', 'M', 'E')
252  || AV_RB32(version) == MKBETAG('L', 'a', 'v', 'f')
253  || AV_RB32(version) == MKBETAG('L', 'a', 'v', 'c')
254  ) {
255 
256  mp3->start_pad = v>>12;
257  mp3-> end_pad = v&4095;
258  st->internal->start_skip_samples = mp3->start_pad + 528 + 1;
259  if (mp3->frames) {
260  st->internal->first_discard_sample = -mp3->end_pad + 528 + 1 + mp3->frames * (int64_t)spf;
261  st->internal->last_discard_sample = mp3->frames * (int64_t)spf;
262  }
263  if (!st->start_time)
265  (AVRational){1, c->sample_rate},
266  st->time_base);
267  av_log(s, AV_LOG_DEBUG, "pad %d %d\n", mp3->start_pad, mp3-> end_pad);
268  }
269 
270  /* Misc */
271  avio_r8(s->pb);
272 
273  /* MP3 gain */
274  avio_r8(s->pb);
275 
276  /* Preset and surround info */
277  avio_rb16(s->pb);
278 
279  /* Music length */
280  avio_rb32(s->pb);
281 
282  /* Music CRC */
283  avio_rb16(s->pb);
284 
285  /* Info Tag CRC */
286  crc = ffio_get_checksum(s->pb);
287  v = avio_rb16(s->pb);
288 
289  if (v == crc) {
290  ff_replaygain_export_raw(st, r_gain, peak, a_gain, 0);
291  av_dict_set(&st->metadata, "encoder", version, 0);
292  }
293 }
294 
295 static void mp3_parse_vbri_tag(AVFormatContext *s, AVStream *st, int64_t base)
296 {
297  uint32_t v;
298  MP3DecContext *mp3 = s->priv_data;
299 
300  /* Check for VBRI tag (always 32 bytes after end of mpegaudio header) */
301  avio_seek(s->pb, base + 4 + 32, SEEK_SET);
302  v = avio_rb32(s->pb);
303  if (v == MKBETAG('V', 'B', 'R', 'I')) {
304  /* Check tag version */
305  if (avio_rb16(s->pb) == 1) {
306  /* skip delay and quality */
307  avio_skip(s->pb, 4);
308  mp3->header_filesize = avio_rb32(s->pb);
309  mp3->frames = avio_rb32(s->pb);
310  }
311  }
312 }
313 
314 /**
315  * Try to find Xing/Info/VBRI tags and compute duration from info therein
316  */
318 {
319  uint32_t v, spf;
321  int vbrtag_size = 0;
322  MP3DecContext *mp3 = s->priv_data;
323  int ret;
324 
326 
327  v = avio_rb32(s->pb);
328 
330  if (ret < 0)
331  return ret;
332  else if (ret == 0)
333  vbrtag_size = c.frame_size;
334  if (c.layer != 3)
335  return -1;
336 
337  spf = c.lsf ? 576 : 1152; /* Samples per frame, layer 3 */
338 
339  mp3->frames = 0;
340  mp3->header_filesize = 0;
341 
342  mp3_parse_info_tag(s, st, &c, spf);
343  mp3_parse_vbri_tag(s, st, base);
344 
345  if (!mp3->frames && !mp3->header_filesize)
346  return -1;
347 
348  /* Skip the vbr tag frame */
349  avio_seek(s->pb, base + vbrtag_size, SEEK_SET);
350 
351  if (mp3->frames)
352  st->duration = av_rescale_q(mp3->frames, (AVRational){spf, c.sample_rate},
353  st->time_base);
354  if (mp3->header_filesize && mp3->frames && !mp3->is_cbr)
355  st->codecpar->bit_rate = av_rescale(mp3->header_filesize, 8 * c.sample_rate, mp3->frames * (int64_t)spf);
356 
357  return 0;
358 }
359 
361 {
362  MP3DecContext *mp3 = s->priv_data;
363  AVStream *st;
364  int64_t off;
365  int ret;
366  int i;
367 
368  s->metadata = s->internal->id3v2_meta;
369  s->internal->id3v2_meta = NULL;
370 
371  st = avformat_new_stream(s, NULL);
372  if (!st)
373  return AVERROR(ENOMEM);
374 
378  st->start_time = 0;
379 
380  // lcm of all mp3 sample rates
381  avpriv_set_pts_info(st, 64, 1, 14112000);
382 
383  s->pb->maxsize = -1;
384  off = avio_tell(s->pb);
385 
386  if (!av_dict_get(s->metadata, "", NULL, AV_DICT_IGNORE_SUFFIX))
387  ff_id3v1_read(s);
388 
389  if (s->pb->seekable & AVIO_SEEKABLE_NORMAL)
390  mp3->filesize = avio_size(s->pb);
391 
392  if (mp3_parse_vbr_tags(s, st, off) < 0)
393  avio_seek(s->pb, off, SEEK_SET);
394 
395  ret = ff_replaygain_export(st, s->metadata);
396  if (ret < 0)
397  return ret;
398 
399  off = avio_tell(s->pb);
400  for (i = 0; i < 64 * 1024; i++) {
401  uint32_t header, header2;
402  int frame_size;
403  if (!(i&1023))
404  ffio_ensure_seekback(s->pb, i + 1024 + 4);
405  frame_size = check(s->pb, off + i, &header);
406  if (frame_size > 0) {
407  ret = avio_seek(s->pb, off, SEEK_SET);
408  if (ret < 0)
409  return ret;
410  ffio_ensure_seekback(s->pb, i + 1024 + frame_size + 4);
411  ret = check(s->pb, off + i + frame_size, &header2);
412  if (ret >= 0 &&
413  (header & MP3_MASK) == (header2 & MP3_MASK))
414  {
415  av_log(s, i > 0 ? AV_LOG_INFO : AV_LOG_VERBOSE, "Skipping %d bytes of junk at %"PRId64".\n", i, off);
416  ret = avio_seek(s->pb, off + i, SEEK_SET);
417  if (ret < 0)
418  return ret;
419  break;
420  } else if (ret == CHECK_SEEK_FAILED) {
421  av_log(s, AV_LOG_ERROR, "Invalid frame size (%d): Could not seek to %"PRId64".\n", frame_size, off + i + frame_size);
422  return AVERROR(EINVAL);
423  }
424  } else if (frame_size == CHECK_SEEK_FAILED) {
425  av_log(s, AV_LOG_ERROR, "Failed to read frame size: Could not seek to %"PRId64".\n", (int64_t) (i + 1024 + frame_size + 4));
426  return AVERROR(EINVAL);
427  }
428  ret = avio_seek(s->pb, off, SEEK_SET);
429  if (ret < 0)
430  return ret;
431  }
432 
433  // the seek index is relative to the end of the xing vbr headers
434  for (i = 0; i < st->nb_index_entries; i++)
435  st->index_entries[i].pos += avio_tell(s->pb);
436 
437  /* the parameters will be extracted from the compressed bitstream */
438  return 0;
439 }
440 
441 #define MP3_PACKET_SIZE 1024
442 
444 {
445  MP3DecContext *mp3 = s->priv_data;
446  int ret, size;
447  int64_t pos;
448 
450  pos = avio_tell(s->pb);
451  if (mp3->filesize > ID3v1_TAG_SIZE && pos < mp3->filesize)
452  size= FFMIN(size, mp3->filesize - pos);
453 
454  ret = av_get_packet(s->pb, pkt, size);
455  if (ret <= 0) {
456  if(ret<0)
457  return ret;
458  return AVERROR_EOF;
459  }
460 
462  pkt->stream_index = 0;
463 
464  return ret;
465 }
466 
467 #define SEEK_WINDOW 4096
468 
469 static int check(AVIOContext *pb, int64_t pos, uint32_t *ret_header)
470 {
471  int64_t ret = avio_seek(pb, pos, SEEK_SET);
472  uint8_t header_buf[4];
473  unsigned header;
474  MPADecodeHeader sd;
475  if (ret < 0)
476  return CHECK_SEEK_FAILED;
477 
478  ret = avio_read(pb, &header_buf[0], 4);
479  /* We should always find four bytes for a valid mpa header. */
480  if (ret < 4)
481  return CHECK_SEEK_FAILED;
482 
483  header = AV_RB32(&header_buf[0]);
484  if (ff_mpa_check_header(header) < 0)
485  return CHECK_WRONG_HEADER;
486  if (avpriv_mpegaudio_decode_header(&sd, header) == 1)
487  return CHECK_WRONG_HEADER;
488 
489  if (ret_header)
490  *ret_header = header;
491  return sd.frame_size;
492 }
493 
494 static int64_t mp3_sync(AVFormatContext *s, int64_t target_pos, int flags)
495 {
496  int dir = (flags&AVSEEK_FLAG_BACKWARD) ? -1 : 1;
497  int64_t best_pos;
498  int best_score, i, j;
499  int64_t ret;
500 
501  avio_seek(s->pb, FFMAX(target_pos - SEEK_WINDOW, 0), SEEK_SET);
502  ret = avio_seek(s->pb, target_pos, SEEK_SET);
503  if (ret < 0)
504  return ret;
505 
506 #define MIN_VALID 3
507  best_pos = target_pos;
508  best_score = 999;
509  for (i = 0; i < SEEK_WINDOW; i++) {
510  int64_t pos = target_pos + (dir > 0 ? i - SEEK_WINDOW/4 : -i);
511  int64_t candidate = -1;
512  int score = 999;
513 
514  if (pos < 0)
515  continue;
516 
517  for (j = 0; j < MIN_VALID; j++) {
518  ret = check(s->pb, pos, NULL);
519  if (ret < 0) {
520  if (ret == CHECK_WRONG_HEADER) {
521  break;
522  } else if (ret == CHECK_SEEK_FAILED) {
523  av_log(s, AV_LOG_ERROR, "Could not seek to %"PRId64".\n", pos);
524  return AVERROR(EINVAL);
525  }
526  }
527  if ((target_pos - pos)*dir <= 0 && FFABS(MIN_VALID/2-j) < score) {
528  candidate = pos;
529  score = FFABS(MIN_VALID/2-j);
530  }
531  pos += ret;
532  }
533  if (best_score > score && j == MIN_VALID) {
534  best_pos = candidate;
535  best_score = score;
536  if(score == 0)
537  break;
538  }
539  }
540 
541  return avio_seek(s->pb, best_pos, SEEK_SET);
542 }
543 
544 static int mp3_seek(AVFormatContext *s, int stream_index, int64_t timestamp,
545  int flags)
546 {
547  MP3DecContext *mp3 = s->priv_data;
548  AVIndexEntry *ie, ie1;
549  AVStream *st = s->streams[0];
550  int64_t best_pos;
551  int fast_seek = s->flags & AVFMT_FLAG_FAST_SEEK;
552  int64_t filesize = mp3->header_filesize;
553 
554  if (filesize <= 0) {
555  int64_t size = avio_size(s->pb);
556  if (size > 0 && size > s->internal->data_offset)
557  filesize = size - s->internal->data_offset;
558  }
559 
560  if (mp3->xing_toc && (mp3->usetoc || (fast_seek && !mp3->is_cbr))) {
561  int64_t ret = av_index_search_timestamp(st, timestamp, flags);
562 
563  // NOTE: The MP3 TOC is not a precise lookup table. Accuracy is worse
564  // for bigger files.
565  av_log(s, AV_LOG_WARNING, "Using MP3 TOC to seek; may be imprecise.\n");
566 
567  if (ret < 0)
568  return ret;
569 
570  ie = &st->index_entries[ret];
571  } else if (fast_seek && st->duration > 0 && filesize > 0) {
572  if (!mp3->is_cbr)
573  av_log(s, AV_LOG_WARNING, "Using scaling to seek VBR MP3; may be imprecise.\n");
574 
575  ie = &ie1;
576  timestamp = av_clip64(timestamp, 0, st->duration);
577  ie->timestamp = timestamp;
578  ie->pos = av_rescale(timestamp, filesize, st->duration) + s->internal->data_offset;
579  } else {
580  return -1; // generic index code
581  }
582 
583  best_pos = mp3_sync(s, ie->pos, flags);
584  if (best_pos < 0)
585  return best_pos;
586 
587  if (mp3->is_cbr && ie == &ie1 && mp3->frames) {
588  int frame_duration = av_rescale(st->duration, 1, mp3->frames);
589  ie1.timestamp = frame_duration * av_rescale(best_pos - s->internal->data_offset, mp3->frames, mp3->header_filesize);
590  }
591 
592  ff_update_cur_dts(s, st, ie->timestamp);
593  return 0;
594 }
595 
596 static const AVOption options[] = {
597  { "usetoc", "use table of contents", offsetof(MP3DecContext, usetoc), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, AV_OPT_FLAG_DECODING_PARAM},
598  { NULL },
599 };
600 
601 static const AVClass demuxer_class = {
602  .class_name = "mp3",
603  .item_name = av_default_item_name,
604  .option = options,
605  .version = LIBAVUTIL_VERSION_INT,
606  .category = AV_CLASS_CATEGORY_DEMUXER,
607 };
608 
610  .name = "mp3",
611  .long_name = NULL_IF_CONFIG_SMALL("MP2/3 (MPEG audio layer 2/3)"),
612  .read_probe = mp3_read_probe,
613  .read_header = mp3_read_header,
614  .read_packet = mp3_read_packet,
615  .read_seek = mp3_seek,
616  .priv_data_size = sizeof(MP3DecContext),
618  .extensions = "mp2,mp3,m2a,mpa", /* XXX: use probe */
619  .priv_class = &demuxer_class,
620 };
uint8_t
int32_t
static int64_t fsize(FILE *f)
Definition: audiomatch.c:29
Libavcodec external API header.
Main libavformat public API header.
#define AVINDEX_KEYFRAME
Definition: avformat.h:811
#define AVFMT_FLAG_FAST_SEEK
Enable fast, but inaccurate seeks for some formats.
Definition: avformat.h:1391
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:451
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:310
#define AVSEEK_FLAG_BACKWARD
Definition: avformat.h:2415
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:463
@ AVSTREAM_PARSE_FULL_RAW
full parsing and repack with timestamp and position generation by parser for raw this assumes that ea...
Definition: avformat.h:798
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:253
#define AVIO_SEEKABLE_NORMAL
Seeking works like for a local file.
Definition: avio.h:40
int64_t avio_size(AVIOContext *s)
Get the filesize.
Definition: aviobuf.c:342
unsigned int avio_rb16(AVIOContext *s)
Definition: aviobuf.c:766
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:557
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:337
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:633
unsigned int avio_rb24(AVIOContext *s)
Definition: aviobuf.c:774
unsigned int avio_rb32(AVIOContext *s)
Definition: aviobuf.c:781
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:624
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:612
unsigned long ff_crcA001_update(unsigned long checksum, const uint8_t *buf, unsigned int len)
Definition: aviobuf.c:598
unsigned long ffio_get_checksum(AVIOContext *s)
Definition: aviobuf.c:604
int ffio_ensure_seekback(AVIOContext *s, int64_t buf_size)
Ensures that the requested seekback buffer size will be available.
Definition: aviobuf.c:998
#define AV_RB32
Definition: intreadwrite.h:130
#define flags(name, subs,...)
Definition: cbs_av1.c:561
#define s(width, name)
Definition: cbs_vp9.c:257
#define FFMIN(a, b)
Definition: common.h:105
#define MKBETAG(a, b, c, d)
Definition: common.h:479
#define FFMAX(a, b)
Definition: common.h:103
#define av_clip64
Definition: common.h:125
#define FFABS(a)
Absolute value, Note, INT_MIN / INT64_MIN result in undefined behavior as they are not representable ...
Definition: common.h:72
#define NULL
Definition: coverity.c:32
Public header for CRC hash function implementation.
Public dictionary API.
@ AV_OPT_TYPE_BOOL
Definition: opt.h:242
@ AV_CODEC_ID_MP3
preferred ID for decoding MPEG audio layer 1, 2 or 3
Definition: codec_id.h:425
#define AV_PKT_FLAG_CORRUPT
The packet content is corrupted.
Definition: packet.h:411
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4509
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:2013
int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags)
Get the index for a specific timestamp.
Definition: utils.c:2130
#define AV_DICT_IGNORE_SUFFIX
Return first entry in a dictionary whose first part corresponds to the search key,...
Definition: dict.h:70
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
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
#define AVERROR_EOF
End of file.
Definition: error.h:55
#define AVERROR(e)
Definition: error.h:43
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:215
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:200
#define AV_LOG_VERBOSE
Detailed information.
Definition: log.h:210
#define AV_LOG_INFO
Standard information.
Definition: log.h:205
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:194
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:235
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
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
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
void ff_id3v1_read(AVFormatContext *s)
Read an ID3v1 tag.
Definition: id3v1.c:279
#define ID3v1_TAG_SIZE
Definition: id3v1.h:27
int ff_id3v2_tag_len(const uint8_t *buf)
Get the length of an ID3v2 tag.
Definition: id3v2.c:156
int ff_id3v2_match(const uint8_t *buf, const char *magic)
Detect ID3v2 Header.
Definition: id3v2.c:143
#define ID3v2_DEFAULT_MAGIC
Default magic bytes for ID3v2 header: "ID3".
Definition: id3v2.h:35
int i
Definition: input.c:407
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:1927
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:4945
#define PROBE_BUF_MAX
Definition: internal.h:34
common internal API header
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
version
Definition: libkvazaar.c:326
@ AV_CLASS_CATEGORY_DEMUXER
Definition: log.h:34
CheckRet
Definition: mp3dec.c:58
@ CHECK_SEEK_FAILED
Definition: mp3dec.c:60
@ CHECK_WRONG_HEADER
Definition: mp3dec.c:59
static int mp3_read_header(AVFormatContext *s)
Definition: mp3dec.c:360
#define XING_FLAC_QSCALE
Definition: mp3dec.c:41
#define MIN_VALID
static int mp3_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
Definition: mp3dec.c:544
#define MP3_PACKET_SIZE
Definition: mp3dec.c:441
static const AVOption options[]
Definition: mp3dec.c:596
static void mp3_parse_info_tag(AVFormatContext *s, AVStream *st, MPADecodeHeader *c, uint32_t spf)
Definition: mp3dec.c:157
static int check(AVIOContext *pb, int64_t pos, uint32_t *header)
Definition: mp3dec.c:469
#define XING_FLAG_FRAMES
Definition: mp3dec.c:38
static int64_t mp3_sync(AVFormatContext *s, int64_t target_pos, int flags)
Definition: mp3dec.c:494
static void mp3_parse_vbri_tag(AVFormatContext *s, AVStream *st, int64_t base)
Definition: mp3dec.c:295
#define MIDDLE_BITS(k, m, n)
#define SEEK_WINDOW
Definition: mp3dec.c:467
#define XING_TOC_COUNT
Definition: mp3dec.c:43
static const AVClass demuxer_class
Definition: mp3dec.c:601
AVInputFormat ff_mp3_demuxer
Definition: mp3dec.c:609
static void read_xing_toc(AVFormatContext *s, int64_t filesize, int64_t duration)
Definition: mp3dec.c:132
static int mp3_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: mp3dec.c:443
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:317
#define XING_FLAG_SIZE
Definition: mp3dec.c:39
static int mp3_read_probe(const AVProbeData *p)
Definition: mp3dec.c:67
#define XING_FLAG_TOC
Definition: mp3dec.c:40
static const uint8_t xing_offtbl[2][2]
Definition: mp3enc.c:138
int avpriv_mpegaudio_decode_header(MPADecodeHeader *s, uint32_t header)
MPEG Audio header decoder.
static int ff_mpa_check_header(uint32_t header)
#define MP3_MASK
int frame_size
Definition: mxfenc.c:2206
AVOptions.
#define AV_OPT_FLAG_DECODING_PARAM
a generic parameter which can be set by the user for demuxing or decoding
Definition: opt.h:279
int ff_replaygain_export(AVStream *st, AVDictionary *metadata)
Parse replaygain tags and export them as per-stream side data.
Definition: replaygain.c:91
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
static const uint8_t header[24]
Definition: sdr2.c:67
unsigned int pos
Definition: spdifenc.c:412
Describe the class of an AVClass context structure.
Definition: log.h:67
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
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: codec_par.h:89
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
Format I/O context.
Definition: avformat.h:1232
Bytestream IO Context.
Definition: avio.h:161
int64_t pos
Definition: avformat.h:804
int64_t timestamp
Timestamp in AVStream.time_base units, preferably the time from which on correctly decoded frames are...
Definition: avformat.h:805
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:645
AVOption.
Definition: opt.h:248
This structure stores compressed data.
Definition: packet.h:346
int stream_index
Definition: packet.h:371
int flags
A combination of AV_PKT_FLAG values.
Definition: packet.h:375
This structure contains the data a format has to probe a file.
Definition: avformat.h:441
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
Rational number (pair of numerator and denominator).
Definition: rational.h:58
int64_t first_discard_sample
If not 0, the first audio sample that should be discarded from the stream.
Definition: internal.h:275
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: internal.h:267
int64_t last_discard_sample
The sample after last sample that is intended to be discarded after first_discard_sample.
Definition: internal.h:282
Stream structure.
Definition: avformat.h:873
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1038
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:922
AVDictionary * metadata
Definition: avformat.h:937
int nb_index_entries
Definition: avformat.h:1092
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base.
Definition: avformat.h:912
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented.
Definition: avformat.h:902
AVIndexEntry * index_entries
Only used if the format does not support seeking natively.
Definition: avformat.h:1090
enum AVStreamParseType need_parsing
Definition: avformat.h:1081
AVStreamInternal * internal
An opaque field for libavformat internal usage.
Definition: avformat.h:1113
int end_pad
Definition: mp3dec.c:51
int is_cbr
Definition: mp3dec.c:55
int64_t filesize
Definition: mp3dec.c:48
int usetoc
Definition: mp3dec.c:52
unsigned frames
Definition: mp3dec.c:53
unsigned header_filesize
Definition: mp3dec.c:54
int start_pad
Definition: mp3dec.c:50
int xing_toc
Definition: mp3dec.c:49
#define av_log(a,...)
int64_t duration
Definition: movenc.c:64
AVPacket * pkt
Definition: movenc.c:59
int frames
Definition: movenc.c:66
int size
const char * b
Definition: vf_curves.c:118
float delta
float min
uint8_t base
Definition: vp3data.h:141
static double c[64]