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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 #define SAME_HEADER_MASK \
46  (0xffe00000 | (3 << 17) | (3 << 10) | (3 << 19))
47 
48 typedef struct {
49  AVClass *class;
50  int64_t filesize;
51  int xing_toc;
52  int start_pad;
53  int end_pad;
54  int usetoc;
55  unsigned frames; /* Total number of frames in file */
56  unsigned header_filesize; /* Total number of bytes in the stream */
57  int is_cbr;
59 
60 enum CheckRet {
63 };
64 
65 static int check(AVIOContext *pb, int64_t pos, uint32_t *header);
66 
67 /* mp3 read */
68 
70 {
71  int max_frames, first_frames = 0;
72  int whole_used = 0;
73  int frames, ret;
74  uint32_t header;
75  const uint8_t *buf, *buf0, *buf2, *end;
76 
77  buf0 = p->buf;
78  end = p->buf + p->buf_size - sizeof(uint32_t);
79  while(buf0 < end && !*buf0)
80  buf0++;
81 
82  max_frames = 0;
83  buf = buf0;
84 
85  for(; buf < end; buf= buf2+1) {
86  buf2 = buf;
87  for(frames = 0; buf2 < end; frames++) {
89 
90  header = AV_RB32(buf2);
91  ret = avpriv_mpegaudio_decode_header(&h, header);
92  if (ret != 0)
93  break;
94  buf2 += h.frame_size;
95  }
96  max_frames = FFMAX(max_frames, frames);
97  if(buf == buf0) {
98  first_frames= frames;
99  if (buf2 == end + sizeof(uint32_t))
100  whole_used = 1;
101  }
102  }
103  // keep this in sync with ac3 probe, both need to avoid
104  // issues with MPEG-files!
105  if (first_frames>=7) return AVPROBE_SCORE_EXTENSION + 1;
106  else if(max_frames>200)return AVPROBE_SCORE_EXTENSION;
107  else if(max_frames>=4 && max_frames >= p->buf_size/10000) return AVPROBE_SCORE_EXTENSION / 2;
108  else if(ff_id3v2_match(buf0, ID3v2_DEFAULT_MAGIC) && 2*ff_id3v2_tag_len(buf0) >= p->buf_size)
110  else if(first_frames > 1 && whole_used) return 5;
111  else if(max_frames>=1 && max_frames >= p->buf_size/10000) return 1;
112  else return 0;
113 //mpegps_mp3_unrecognized_format.mpg has max_frames=3
114 }
115 
116 static void read_xing_toc(AVFormatContext *s, int64_t filesize, int64_t duration)
117 {
118  int i;
119  MP3DecContext *mp3 = s->priv_data;
120  int fast_seek = s->flags & AVFMT_FLAG_FAST_SEEK;
121  int fill_index = (mp3->usetoc || fast_seek) && duration > 0;
122 
123  if (!filesize &&
124  !(filesize = avio_size(s->pb))) {
125  av_log(s, AV_LOG_WARNING, "Cannot determine file size, skipping TOC table.\n");
126  fill_index = 0;
127  }
128 
129  for (i = 0; i < XING_TOC_COUNT; i++) {
130  uint8_t b = avio_r8(s->pb);
131  if (fill_index)
133  av_rescale(b, filesize, 256),
134  av_rescale(i, duration, XING_TOC_COUNT),
135  0, 0, AVINDEX_KEYFRAME);
136  }
137  if (fill_index)
138  mp3->xing_toc = 1;
139 }
140 
142  MPADecodeHeader *c, uint32_t spf)
143 {
144 #define LAST_BITS(k, n) ((k) & ((1 << (n)) - 1))
145 #define MIDDLE_BITS(k, m, n) LAST_BITS((k) >> (m), ((n) - (m)))
146 
147  uint16_t crc;
148  uint32_t v;
149 
150  char version[10];
151 
152  uint32_t peak = 0;
153  int32_t r_gain = INT32_MIN, a_gain = INT32_MIN;
154 
155  MP3DecContext *mp3 = s->priv_data;
156  static const int64_t xing_offtbl[2][2] = {{32, 17}, {17,9}};
157  uint64_t fsize = avio_size(s->pb);
158  fsize = fsize >= avio_tell(s->pb) ? fsize - avio_tell(s->pb) : 0;
159 
160  /* Check for Xing / Info tag */
161  avio_skip(s->pb, xing_offtbl[c->lsf == 1][c->nb_channels == 1]);
162  v = avio_rb32(s->pb);
163  mp3->is_cbr = v == MKBETAG('I', 'n', 'f', 'o');
164  if (v != MKBETAG('X', 'i', 'n', 'g') && !mp3->is_cbr)
165  return;
166 
167  v = avio_rb32(s->pb);
168  if (v & XING_FLAG_FRAMES)
169  mp3->frames = avio_rb32(s->pb);
170  if (v & XING_FLAG_SIZE)
171  mp3->header_filesize = avio_rb32(s->pb);
172  if (fsize && mp3->header_filesize) {
173  uint64_t min, delta;
174  min = FFMIN(fsize, mp3->header_filesize);
175  delta = FFMAX(fsize, mp3->header_filesize) - min;
176  if (fsize > mp3->header_filesize && delta > min >> 4) {
177  mp3->frames = 0;
179  "invalid concatenated file detected - using bitrate for duration\n");
180  } else if (delta > min >> 4) {
182  "filesize and duration do not match (growing file?)\n");
183  }
184  }
185  if (v & XING_FLAG_TOC)
187  (AVRational){spf, c->sample_rate},
188  st->time_base));
189  /* VBR quality */
190  if (v & XING_FLAC_QSCALE)
191  avio_rb32(s->pb);
192 
193  /* Encoder short version string */
194  memset(version, 0, sizeof(version));
195  avio_read(s->pb, version, 9);
196 
197  /* Info Tag revision + VBR method */
198  avio_r8(s->pb);
199 
200  /* Lowpass filter value */
201  avio_r8(s->pb);
202 
203  /* ReplayGain peak */
204  v = avio_rb32(s->pb);
205  peak = av_rescale(v, 100000, 1 << 23);
206 
207  /* Radio ReplayGain */
208  v = avio_rb16(s->pb);
209 
210  if (MIDDLE_BITS(v, 13, 15) == 1) {
211  r_gain = MIDDLE_BITS(v, 0, 8) * 10000;
212 
213  if (v & (1 << 9))
214  r_gain *= -1;
215  }
216 
217  /* Audiophile ReplayGain */
218  v = avio_rb16(s->pb);
219 
220  if (MIDDLE_BITS(v, 13, 15) == 2) {
221  a_gain = MIDDLE_BITS(v, 0, 8) * 10000;
222 
223  if (v & (1 << 9))
224  a_gain *= -1;
225  }
226 
227  /* Encoding flags + ATH Type */
228  avio_r8(s->pb);
229 
230  /* if ABR {specified bitrate} else {minimal bitrate} */
231  avio_r8(s->pb);
232 
233  /* Encoder delays */
234  v= avio_rb24(s->pb);
235  if(AV_RB32(version) == MKBETAG('L', 'A', 'M', 'E')
236  || AV_RB32(version) == MKBETAG('L', 'a', 'v', 'f')
237  || AV_RB32(version) == MKBETAG('L', 'a', 'v', 'c')
238  ) {
239 
240  mp3->start_pad = v>>12;
241  mp3-> end_pad = v&4095;
242  st->start_skip_samples = mp3->start_pad + 528 + 1;
243  if (mp3->frames) {
244  st->first_discard_sample = -mp3->end_pad + 528 + 1 + mp3->frames * (int64_t)spf;
245  st->last_discard_sample = mp3->frames * (int64_t)spf;
246  }
247  if (!st->start_time)
248  st->start_time = av_rescale_q(st->start_skip_samples,
249  (AVRational){1, c->sample_rate},
250  st->time_base);
251  av_log(s, AV_LOG_DEBUG, "pad %d %d\n", mp3->start_pad, mp3-> end_pad);
252  }
253 
254  /* Misc */
255  avio_r8(s->pb);
256 
257  /* MP3 gain */
258  avio_r8(s->pb);
259 
260  /* Preset and surround info */
261  avio_rb16(s->pb);
262 
263  /* Music length */
264  avio_rb32(s->pb);
265 
266  /* Music CRC */
267  avio_rb16(s->pb);
268 
269  /* Info Tag CRC */
270  crc = ffio_get_checksum(s->pb);
271  v = avio_rb16(s->pb);
272 
273  if (v == crc) {
274  ff_replaygain_export_raw(st, r_gain, peak, a_gain, 0);
275  av_dict_set(&st->metadata, "encoder", version, 0);
276  }
277 }
278 
279 static void mp3_parse_vbri_tag(AVFormatContext *s, AVStream *st, int64_t base)
280 {
281  uint32_t v;
282  MP3DecContext *mp3 = s->priv_data;
283 
284  /* Check for VBRI tag (always 32 bytes after end of mpegaudio header) */
285  avio_seek(s->pb, base + 4 + 32, SEEK_SET);
286  v = avio_rb32(s->pb);
287  if (v == MKBETAG('V', 'B', 'R', 'I')) {
288  /* Check tag version */
289  if (avio_rb16(s->pb) == 1) {
290  /* skip delay and quality */
291  avio_skip(s->pb, 4);
292  mp3->header_filesize = avio_rb32(s->pb);
293  mp3->frames = avio_rb32(s->pb);
294  }
295  }
296 }
297 
298 /**
299  * Try to find Xing/Info/VBRI tags and compute duration from info therein
300  */
301 static int mp3_parse_vbr_tags(AVFormatContext *s, AVStream *st, int64_t base)
302 {
303  uint32_t v, spf;
305  int vbrtag_size = 0;
306  MP3DecContext *mp3 = s->priv_data;
307  int ret;
308 
310 
311  v = avio_rb32(s->pb);
312 
313  ret = avpriv_mpegaudio_decode_header(&c, v);
314  if (ret < 0)
315  return ret;
316  else if (ret == 0)
317  vbrtag_size = c.frame_size;
318  if(c.layer != 3)
319  return -1;
320 
321  spf = c.lsf ? 576 : 1152; /* Samples per frame, layer 3 */
322 
323  mp3->frames = 0;
324  mp3->header_filesize = 0;
325 
326  mp3_parse_info_tag(s, st, &c, spf);
327  mp3_parse_vbri_tag(s, st, base);
328 
329  if (!mp3->frames && !mp3->header_filesize)
330  return -1;
331 
332  /* Skip the vbr tag frame */
333  avio_seek(s->pb, base + vbrtag_size, SEEK_SET);
334 
335  if (mp3->frames)
336  st->duration = av_rescale_q(mp3->frames, (AVRational){spf, c.sample_rate},
337  st->time_base);
338  if (mp3->header_filesize && mp3->frames && !mp3->is_cbr)
339  st->codecpar->bit_rate = av_rescale(mp3->header_filesize, 8 * c.sample_rate, mp3->frames * (int64_t)spf);
340 
341  return 0;
342 }
343 
345 {
346  MP3DecContext *mp3 = s->priv_data;
347  AVStream *st;
348  int64_t off;
349  int ret;
350  int i;
351 
352  s->metadata = s->internal->id3v2_meta;
353  s->internal->id3v2_meta = NULL;
354 
355  st = avformat_new_stream(s, NULL);
356  if (!st)
357  return AVERROR(ENOMEM);
358 
362  st->start_time = 0;
363 
364  // lcm of all mp3 sample rates
365  avpriv_set_pts_info(st, 64, 1, 14112000);
366 
367  s->pb->maxsize = -1;
368  off = avio_tell(s->pb);
369 
371  ff_id3v1_read(s);
372 
374  mp3->filesize = avio_size(s->pb);
375 
376  if (mp3_parse_vbr_tags(s, st, off) < 0)
377  avio_seek(s->pb, off, SEEK_SET);
378 
379  ret = ff_replaygain_export(st, s->metadata);
380  if (ret < 0)
381  return ret;
382 
383  off = avio_tell(s->pb);
384  for (i = 0; i < 64 * 1024; i++) {
385  uint32_t header, header2;
386  int frame_size;
387  if (!(i&1023))
388  ffio_ensure_seekback(s->pb, i + 1024 + 4);
389  frame_size = check(s->pb, off + i, &header);
390  if (frame_size > 0) {
391  ret = avio_seek(s->pb, off, SEEK_SET);
392  if (ret < 0)
393  return ret;
394  ffio_ensure_seekback(s->pb, i + 1024 + frame_size + 4);
395  ret = check(s->pb, off + i + frame_size, &header2);
396  if (ret >= 0 &&
397  (header & SAME_HEADER_MASK) == (header2 & SAME_HEADER_MASK))
398  {
399  av_log(s, i > 0 ? AV_LOG_INFO : AV_LOG_VERBOSE, "Skipping %d bytes of junk at %"PRId64".\n", i, off);
400  ret = avio_seek(s->pb, off + i, SEEK_SET);
401  if (ret < 0)
402  return ret;
403  break;
404  } else if (ret == CHECK_SEEK_FAILED) {
405  av_log(s, AV_LOG_ERROR, "Invalid frame size (%d): Could not seek to %"PRId64".\n", frame_size, off + i + frame_size);
406  return AVERROR(EINVAL);
407  }
408  } else if (frame_size == CHECK_SEEK_FAILED) {
409  av_log(s, AV_LOG_ERROR, "Failed to read frame size: Could not seek to %"PRId64".\n", (int64_t) (i + 1024 + frame_size + 4));
410  return AVERROR(EINVAL);
411  }
412  ret = avio_seek(s->pb, off, SEEK_SET);
413  if (ret < 0)
414  return ret;
415  }
416 
417  // the seek index is relative to the end of the xing vbr headers
418  for (i = 0; i < st->nb_index_entries; i++)
419  st->index_entries[i].pos += avio_tell(s->pb);
420 
421  /* the parameters will be extracted from the compressed bitstream */
422  return 0;
423 }
424 
425 #define MP3_PACKET_SIZE 1024
426 
428 {
429  MP3DecContext *mp3 = s->priv_data;
430  int ret, size;
431  int64_t pos;
432 
433  size= MP3_PACKET_SIZE;
434  pos = avio_tell(s->pb);
435  if(mp3->filesize > ID3v1_TAG_SIZE && pos < mp3->filesize)
436  size= FFMIN(size, mp3->filesize - pos);
437 
438  ret= av_get_packet(s->pb, pkt, size);
439  if (ret <= 0) {
440  if(ret<0)
441  return ret;
442  return AVERROR_EOF;
443  }
444 
445  pkt->flags &= ~AV_PKT_FLAG_CORRUPT;
446  pkt->stream_index = 0;
447 
448  return ret;
449 }
450 
451 #define SEEK_WINDOW 4096
452 
453 static int check(AVIOContext *pb, int64_t pos, uint32_t *ret_header)
454 {
455  int64_t ret = avio_seek(pb, pos, SEEK_SET);
456  uint8_t header_buf[4];
457  unsigned header;
458  MPADecodeHeader sd;
459  if (ret < 0)
460  return CHECK_SEEK_FAILED;
461 
462  ret = avio_read(pb, &header_buf[0], 4);
463  /* We should always find four bytes for a valid mpa header. */
464  if (ret < 4)
465  return CHECK_SEEK_FAILED;
466 
467  header = AV_RB32(&header_buf[0]);
468  if (ff_mpa_check_header(header) < 0)
469  return CHECK_WRONG_HEADER;
470  if (avpriv_mpegaudio_decode_header(&sd, header) == 1)
471  return CHECK_WRONG_HEADER;
472 
473  if (ret_header)
474  *ret_header = header;
475  return sd.frame_size;
476 }
477 
478 static int64_t mp3_sync(AVFormatContext *s, int64_t target_pos, int flags)
479 {
480  int dir = (flags&AVSEEK_FLAG_BACKWARD) ? -1 : 1;
481  int64_t best_pos;
482  int best_score, i, j;
483  int64_t ret;
484 
485  avio_seek(s->pb, FFMAX(target_pos - SEEK_WINDOW, 0), SEEK_SET);
486  ret = avio_seek(s->pb, target_pos, SEEK_SET);
487  if (ret < 0)
488  return ret;
489 
490 #define MIN_VALID 3
491  best_pos = target_pos;
492  best_score = 999;
493  for(i=0; i<SEEK_WINDOW; i++) {
494  int64_t pos = target_pos + (dir > 0 ? i - SEEK_WINDOW/4 : -i);
495  int64_t candidate = -1;
496  int score = 999;
497 
498  if (pos < 0)
499  continue;
500 
501  for(j=0; j<MIN_VALID; j++) {
502  ret = check(s->pb, pos, NULL);
503  if(ret < 0) {
504  if (ret == CHECK_WRONG_HEADER) {
505  break;
506  } else if (ret == CHECK_SEEK_FAILED) {
507  av_log(s, AV_LOG_ERROR, "Could not seek to %"PRId64".\n", pos);
508  return AVERROR(EINVAL);
509  }
510  }
511  if ((target_pos - pos)*dir <= 0 && abs(MIN_VALID/2-j) < score) {
512  candidate = pos;
513  score = abs(MIN_VALID/2-j);
514  }
515  pos += ret;
516  }
517  if (best_score > score && j == MIN_VALID) {
518  best_pos = candidate;
519  best_score = score;
520  if(score == 0)
521  break;
522  }
523  }
524 
525  return avio_seek(s->pb, best_pos, SEEK_SET);
526 }
527 
528 static int mp3_seek(AVFormatContext *s, int stream_index, int64_t timestamp,
529  int flags)
530 {
531  MP3DecContext *mp3 = s->priv_data;
532  AVIndexEntry *ie, ie1;
533  AVStream *st = s->streams[0];
534  int64_t best_pos;
535  int fast_seek = s->flags & AVFMT_FLAG_FAST_SEEK;
536  int64_t filesize = mp3->header_filesize;
537 
538  if (filesize <= 0) {
539  int64_t size = avio_size(s->pb);
540  if (size > 0 && size > s->internal->data_offset)
541  filesize = size - s->internal->data_offset;
542  }
543 
544  if (mp3->xing_toc && (mp3->usetoc || (fast_seek && !mp3->is_cbr))) {
545  int64_t ret = av_index_search_timestamp(st, timestamp, flags);
546 
547  // NOTE: The MP3 TOC is not a precise lookup table. Accuracy is worse
548  // for bigger files.
549  av_log(s, AV_LOG_WARNING, "Using MP3 TOC to seek; may be imprecise.\n");
550 
551  if (ret < 0)
552  return ret;
553 
554  ie = &st->index_entries[ret];
555  } else if (fast_seek && st->duration > 0 && filesize > 0) {
556  if (!mp3->is_cbr)
557  av_log(s, AV_LOG_WARNING, "Using scaling to seek VBR MP3; may be imprecise.\n");
558 
559  ie = &ie1;
560  timestamp = av_clip64(timestamp, 0, st->duration);
561  ie->timestamp = timestamp;
562  ie->pos = av_rescale(timestamp, filesize, st->duration) + s->internal->data_offset;
563  } else {
564  return -1; // generic index code
565  }
566 
567  best_pos = mp3_sync(s, ie->pos, flags);
568  if (best_pos < 0)
569  return best_pos;
570 
571  if (mp3->is_cbr && ie == &ie1 && mp3->frames) {
572  int frame_duration = av_rescale(st->duration, 1, mp3->frames);
573  ie1.timestamp = frame_duration * av_rescale(best_pos - s->internal->data_offset, mp3->frames, mp3->header_filesize);
574  }
575 
576  ff_update_cur_dts(s, st, ie->timestamp);
577  return 0;
578 }
579 
580 static const AVOption options[] = {
581  { "usetoc", "use table of contents", offsetof(MP3DecContext, usetoc), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, AV_OPT_FLAG_DECODING_PARAM},
582  { NULL },
583 };
584 
585 static const AVClass demuxer_class = {
586  .class_name = "mp3",
587  .item_name = av_default_item_name,
588  .option = options,
589  .version = LIBAVUTIL_VERSION_INT,
590  .category = AV_CLASS_CATEGORY_DEMUXER,
591 };
592 
594  .name = "mp3",
595  .long_name = NULL_IF_CONFIG_SMALL("MP2/3 (MPEG audio layer 2/3)"),
596  .read_probe = mp3_read_probe,
597  .read_header = mp3_read_header,
598  .read_packet = mp3_read_packet,
599  .read_seek = mp3_seek,
600  .priv_data_size = sizeof(MP3DecContext),
602  .extensions = "mp2,mp3,m2a,mpa", /* XXX: use probe */
603  .priv_class = &demuxer_class,
604 };
#define AVSEEK_FLAG_BACKWARD
Definition: avformat.h:2423
#define NULL
Definition: coverity.c:32
AVDictionary * id3v2_meta
ID3v2 tag useful for MP3 demuxing.
Definition: internal.h:147
const char * s
Definition: avisynth_c.h:768
Bytestream IO Context.
Definition: avio.h:161
int64_t avio_size(AVIOContext *s)
Get the filesize.
Definition: aviobuf.c:327
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:1980
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
#define LIBAVUTIL_VERSION_INT
Definition: version.h:86
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:4739
int64_t pos
Definition: avformat.h:820
int64_t data_offset
offset of the first packet
Definition: internal.h:82
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:4128
void ff_id3v1_read(AVFormatContext *s)
Read an ID3v1 tag.
Definition: id3v1.c:235
const char * b
Definition: vf_curves.c:113
#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:239
AVIndexEntry * index_entries
Only used if the format does not support seeking natively.
Definition: avformat.h:1092
AVFormatInternal * internal
An opaque field for libavformat internal usage.
Definition: avformat.h:1780
static void read_xing_toc(AVFormatContext *s, int64_t filesize, int64_t duration)
Definition: mp3dec.c:116
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:322
int version
Definition: avisynth_c.h:766
static AVPacket pkt
unsigned int avio_rb16(AVIOContext *s)
Definition: aviobuf.c:768
#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:267
unsigned frames
Definition: mp3dec.c:55
Format I/O context.
Definition: avformat.h:1349
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:1894
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:60
Public dictionary API.
static int mp3_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: mp3dec.c:427
uint8_t
int usetoc
Definition: mp3dec.c:54
#define XING_FLAG_SIZE
Definition: mp3dec.c:39
float delta
AVOptions.
unsigned int avio_rb32(AVIOContext *s)
Definition: aviobuf.c:783
static int mp3_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
Definition: mp3dec.c:528
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:90
enum AVStreamParseType need_parsing
Definition: avformat.h:1081
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4369
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:87
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1417
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:1460
int avpriv_mpegaudio_decode_header(MPADecodeHeader *s, uint32_t header)
static int flags
Definition: log.c:57
static const uint8_t xing_offtbl[2][2]
Definition: mp3enc.c:126
#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:289
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:548
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:814
#define av_log(a,...)
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:630
int64_t filesize
Definition: mp3dec.c:50
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:827
#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:1567
int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags)
Get the index for a specific timestamp.
Definition: utils.c:2089
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:821
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:179
static int mp3_read_header(AVFormatContext *s)
Definition: mp3dec.c:344
#define SAME_HEADER_MASK
Definition: mp3dec.c:45
#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:556
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:4124
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: avcodec.h:1676
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:621
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:464
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:463
#define SEEK_WINDOW
Definition: mp3dec.c:451
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:609
int seekable
A combination of AVIO_SEEKABLE_ flags or 0 when the stream is not seekable.
Definition: avio.h:261
unsigned int avio_rb24(AVIOContext *s)
Definition: aviobuf.c:776
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:425
#define FFMIN(a, b)
Definition: common.h:96
static int check(AVIOContext *pb, int64_t pos, uint32_t *header)
Definition: mp3dec.c:453
int end_pad
Definition: mp3dec.c:53
static void mp3_parse_info_tag(AVFormatContext *s, AVStream *st, MPADecodeHeader *c, uint32_t spf)
Definition: mp3dec.c:141
int32_t
static int64_t mp3_sync(AVFormatContext *s, int64_t target_pos, int flags)
Definition: mp3dec.c:478
int xing_toc
Definition: mp3dec.c:51
unsigned long ff_crcA001_update(unsigned long checksum, const uint8_t *buf, unsigned int len)
Definition: aviobuf.c:595
static void mp3_parse_vbri_tag(AVFormatContext *s, AVStream *st, int64_t base)
Definition: mp3dec.c:279
int frames
Definition: movenc.c:65
#define MIN_VALID
Stream structure.
Definition: avformat.h:889
static int mp3_read_probe(AVProbeData *p)
Definition: mp3dec.c:69
#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:1820
Libavcodec external API header.
AVIOContext * pb
I/O context.
Definition: avformat.h:1391
#define XING_FLAG_FRAMES
Definition: mp3dec.c:38
void * buf
Definition: avisynth_c.h:690
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:1094
Describe the class of an AVClass context structure.
Definition: log.h:67
static const AVOption options[]
Definition: mp3dec.c:580
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:487
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:601
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:471
This structure contains the data a format has to probe a file.
Definition: avformat.h:461
int ffio_ensure_seekback(AVIOContext *s, int64_t buf_size)
Ensures that the requested seekback buffer size will be available.
Definition: aviobuf.c:967
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:946
MPEG Audio header decoder.
int is_cbr
Definition: mp3dec.c:57
Main libavformat public API header.
unsigned header_filesize
Definition: mp3dec.c:56
static const AVClass demuxer_class
Definition: mp3dec.c:585
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:936
AVInputFormat ff_mp3_demuxer
Definition: mp3dec.c:593
static double c[64]
#define AV_PKT_FLAG_CORRUPT
The packet content is corrupted.
Definition: avcodec.h:1703
#define MKBETAG(a, b, c, d)
Definition: common.h:343
#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:1484
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:1377
#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:301
#define ID3v1_TAG_SIZE
Definition: id3v1.h:27
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:664
#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:52
AVCodecParameters * codecpar
Definition: avformat.h:1252
static int64_t fsize(FILE *f)
Definition: audiomatch.c:28
int stream_index
Definition: avcodec.h:1672
float min
This structure stores compressed data.
Definition: avcodec.h:1647