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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  int framesizes, max_framesizes;
75  uint32_t header;
76  const uint8_t *buf, *buf0, *buf2, *end;
77 
78  buf0 = p->buf;
79  end = p->buf + p->buf_size - sizeof(uint32_t);
80  while(buf0 < end && !*buf0)
81  buf0++;
82 
83  max_frames = 0;
84  max_framesizes = 0;
85  buf = buf0;
86 
87  for(; buf < end; buf= buf2+1) {
88  buf2 = buf;
89  for(framesizes = frames = 0; buf2 < end; frames++) {
91 
92  header = AV_RB32(buf2);
93  ret = avpriv_mpegaudio_decode_header(&h, header);
94  if (ret != 0)
95  break;
96  buf2 += h.frame_size;
97  framesizes += h.frame_size;
98  }
99  max_frames = FFMAX(max_frames, frames);
100  max_framesizes = FFMAX(max_framesizes, framesizes);
101  if(buf == buf0) {
102  first_frames= frames;
103  if (buf2 == end + sizeof(uint32_t))
104  whole_used = 1;
105  }
106  }
107  // keep this in sync with ac3 probe, both need to avoid
108  // issues with MPEG-files!
109  if (first_frames>=7) return AVPROBE_SCORE_EXTENSION + 1;
110  else if(max_frames>200 && p->buf_size < 2*max_framesizes)return AVPROBE_SCORE_EXTENSION;
111  else if(max_frames>=4 && p->buf_size < 2*max_framesizes) return AVPROBE_SCORE_EXTENSION / 2;
112  else if(ff_id3v2_match(buf0, ID3v2_DEFAULT_MAGIC) && 2*ff_id3v2_tag_len(buf0) >= p->buf_size)
114  else if(first_frames > 1 && whole_used) return 5;
115  else if(max_frames>=1 && p->buf_size < 10*max_framesizes) return 1;
116  else return 0;
117 //mpegps_mp3_unrecognized_format.mpg has max_frames=3
118 }
119 
120 static void read_xing_toc(AVFormatContext *s, int64_t filesize, int64_t duration)
121 {
122  int i;
123  MP3DecContext *mp3 = s->priv_data;
124  int fast_seek = s->flags & AVFMT_FLAG_FAST_SEEK;
125  int fill_index = (mp3->usetoc || fast_seek) && duration > 0;
126 
127  if (!filesize &&
128  !(filesize = avio_size(s->pb))) {
129  av_log(s, AV_LOG_WARNING, "Cannot determine file size, skipping TOC table.\n");
130  fill_index = 0;
131  }
132 
133  for (i = 0; i < XING_TOC_COUNT; i++) {
134  uint8_t b = avio_r8(s->pb);
135  if (fill_index)
137  av_rescale(b, filesize, 256),
138  av_rescale(i, duration, XING_TOC_COUNT),
139  0, 0, AVINDEX_KEYFRAME);
140  }
141  if (fill_index)
142  mp3->xing_toc = 1;
143 }
144 
146  MPADecodeHeader *c, uint32_t spf)
147 {
148 #define LAST_BITS(k, n) ((k) & ((1 << (n)) - 1))
149 #define MIDDLE_BITS(k, m, n) LAST_BITS((k) >> (m), ((n) - (m) + 1))
150 
151  uint16_t crc;
152  uint32_t v;
153 
154  char version[10];
155 
156  uint32_t peak = 0;
157  int32_t r_gain = INT32_MIN, a_gain = INT32_MIN;
158 
159  MP3DecContext *mp3 = s->priv_data;
160  static const int64_t xing_offtbl[2][2] = {{32, 17}, {17,9}};
161  uint64_t fsize = avio_size(s->pb);
162  fsize = fsize >= avio_tell(s->pb) ? fsize - avio_tell(s->pb) : 0;
163 
164  /* Check for Xing / Info tag */
165  avio_skip(s->pb, xing_offtbl[c->lsf == 1][c->nb_channels == 1]);
166  v = avio_rb32(s->pb);
167  mp3->is_cbr = v == MKBETAG('I', 'n', 'f', 'o');
168  if (v != MKBETAG('X', 'i', 'n', 'g') && !mp3->is_cbr)
169  return;
170 
171  v = avio_rb32(s->pb);
172  if (v & XING_FLAG_FRAMES)
173  mp3->frames = avio_rb32(s->pb);
174  if (v & XING_FLAG_SIZE)
175  mp3->header_filesize = avio_rb32(s->pb);
176  if (fsize && mp3->header_filesize) {
177  uint64_t min, delta;
178  min = FFMIN(fsize, mp3->header_filesize);
179  delta = FFMAX(fsize, mp3->header_filesize) - min;
180  if (fsize > mp3->header_filesize && delta > min >> 4) {
181  mp3->frames = 0;
183  "invalid concatenated file detected - using bitrate for duration\n");
184  } else if (delta > min >> 4) {
186  "filesize and duration do not match (growing file?)\n");
187  }
188  }
189  if (v & XING_FLAG_TOC)
191  (AVRational){spf, c->sample_rate},
192  st->time_base));
193  /* VBR quality */
194  if (v & XING_FLAC_QSCALE)
195  avio_rb32(s->pb);
196 
197  /* Encoder short version string */
198  memset(version, 0, sizeof(version));
199  avio_read(s->pb, version, 9);
200 
201  /* Info Tag revision + VBR method */
202  avio_r8(s->pb);
203 
204  /* Lowpass filter value */
205  avio_r8(s->pb);
206 
207  /* ReplayGain peak */
208  v = avio_rb32(s->pb);
209  peak = av_rescale(v, 100000, 1 << 23);
210 
211  /* Radio ReplayGain */
212  v = avio_rb16(s->pb);
213 
214  if (MIDDLE_BITS(v, 13, 15) == 1) {
215  r_gain = MIDDLE_BITS(v, 0, 8) * 10000;
216 
217  if (v & (1 << 9))
218  r_gain *= -1;
219  }
220 
221  /* Audiophile ReplayGain */
222  v = avio_rb16(s->pb);
223 
224  if (MIDDLE_BITS(v, 13, 15) == 2) {
225  a_gain = MIDDLE_BITS(v, 0, 8) * 10000;
226 
227  if (v & (1 << 9))
228  a_gain *= -1;
229  }
230 
231  /* Encoding flags + ATH Type */
232  avio_r8(s->pb);
233 
234  /* if ABR {specified bitrate} else {minimal bitrate} */
235  avio_r8(s->pb);
236 
237  /* Encoder delays */
238  v= avio_rb24(s->pb);
239  if(AV_RB32(version) == MKBETAG('L', 'A', 'M', 'E')
240  || AV_RB32(version) == MKBETAG('L', 'a', 'v', 'f')
241  || AV_RB32(version) == MKBETAG('L', 'a', 'v', 'c')
242  ) {
243 
244  mp3->start_pad = v>>12;
245  mp3-> end_pad = v&4095;
246  st->start_skip_samples = mp3->start_pad + 528 + 1;
247  if (mp3->frames) {
248  st->first_discard_sample = -mp3->end_pad + 528 + 1 + mp3->frames * (int64_t)spf;
249  st->last_discard_sample = mp3->frames * (int64_t)spf;
250  }
251  if (!st->start_time)
252  st->start_time = av_rescale_q(st->start_skip_samples,
253  (AVRational){1, c->sample_rate},
254  st->time_base);
255  av_log(s, AV_LOG_DEBUG, "pad %d %d\n", mp3->start_pad, mp3-> end_pad);
256  }
257 
258  /* Misc */
259  avio_r8(s->pb);
260 
261  /* MP3 gain */
262  avio_r8(s->pb);
263 
264  /* Preset and surround info */
265  avio_rb16(s->pb);
266 
267  /* Music length */
268  avio_rb32(s->pb);
269 
270  /* Music CRC */
271  avio_rb16(s->pb);
272 
273  /* Info Tag CRC */
274  crc = ffio_get_checksum(s->pb);
275  v = avio_rb16(s->pb);
276 
277  if (v == crc) {
278  ff_replaygain_export_raw(st, r_gain, peak, a_gain, 0);
279  av_dict_set(&st->metadata, "encoder", version, 0);
280  }
281 }
282 
283 static void mp3_parse_vbri_tag(AVFormatContext *s, AVStream *st, int64_t base)
284 {
285  uint32_t v;
286  MP3DecContext *mp3 = s->priv_data;
287 
288  /* Check for VBRI tag (always 32 bytes after end of mpegaudio header) */
289  avio_seek(s->pb, base + 4 + 32, SEEK_SET);
290  v = avio_rb32(s->pb);
291  if (v == MKBETAG('V', 'B', 'R', 'I')) {
292  /* Check tag version */
293  if (avio_rb16(s->pb) == 1) {
294  /* skip delay and quality */
295  avio_skip(s->pb, 4);
296  mp3->header_filesize = avio_rb32(s->pb);
297  mp3->frames = avio_rb32(s->pb);
298  }
299  }
300 }
301 
302 /**
303  * Try to find Xing/Info/VBRI tags and compute duration from info therein
304  */
305 static int mp3_parse_vbr_tags(AVFormatContext *s, AVStream *st, int64_t base)
306 {
307  uint32_t v, spf;
309  int vbrtag_size = 0;
310  MP3DecContext *mp3 = s->priv_data;
311  int ret;
312 
314 
315  v = avio_rb32(s->pb);
316 
317  ret = avpriv_mpegaudio_decode_header(&c, v);
318  if (ret < 0)
319  return ret;
320  else if (ret == 0)
321  vbrtag_size = c.frame_size;
322  if(c.layer != 3)
323  return -1;
324 
325  spf = c.lsf ? 576 : 1152; /* Samples per frame, layer 3 */
326 
327  mp3->frames = 0;
328  mp3->header_filesize = 0;
329 
330  mp3_parse_info_tag(s, st, &c, spf);
331  mp3_parse_vbri_tag(s, st, base);
332 
333  if (!mp3->frames && !mp3->header_filesize)
334  return -1;
335 
336  /* Skip the vbr tag frame */
337  avio_seek(s->pb, base + vbrtag_size, SEEK_SET);
338 
339  if (mp3->frames)
340  st->duration = av_rescale_q(mp3->frames, (AVRational){spf, c.sample_rate},
341  st->time_base);
342  if (mp3->header_filesize && mp3->frames && !mp3->is_cbr)
343  st->codecpar->bit_rate = av_rescale(mp3->header_filesize, 8 * c.sample_rate, mp3->frames * (int64_t)spf);
344 
345  return 0;
346 }
347 
349 {
350  MP3DecContext *mp3 = s->priv_data;
351  AVStream *st;
352  int64_t off;
353  int ret;
354  int i;
355 
356  s->metadata = s->internal->id3v2_meta;
357  s->internal->id3v2_meta = NULL;
358 
359  st = avformat_new_stream(s, NULL);
360  if (!st)
361  return AVERROR(ENOMEM);
362 
366  st->start_time = 0;
367 
368  // lcm of all mp3 sample rates
369  avpriv_set_pts_info(st, 64, 1, 14112000);
370 
371  s->pb->maxsize = -1;
372  off = avio_tell(s->pb);
373 
375  ff_id3v1_read(s);
376 
378  mp3->filesize = avio_size(s->pb);
379 
380  if (mp3_parse_vbr_tags(s, st, off) < 0)
381  avio_seek(s->pb, off, SEEK_SET);
382 
383  ret = ff_replaygain_export(st, s->metadata);
384  if (ret < 0)
385  return ret;
386 
387  off = avio_tell(s->pb);
388  for (i = 0; i < 64 * 1024; i++) {
389  uint32_t header, header2;
390  int frame_size;
391  if (!(i&1023))
392  ffio_ensure_seekback(s->pb, i + 1024 + 4);
393  frame_size = check(s->pb, off + i, &header);
394  if (frame_size > 0) {
395  ret = avio_seek(s->pb, off, SEEK_SET);
396  if (ret < 0)
397  return ret;
398  ffio_ensure_seekback(s->pb, i + 1024 + frame_size + 4);
399  ret = check(s->pb, off + i + frame_size, &header2);
400  if (ret >= 0 &&
401  (header & SAME_HEADER_MASK) == (header2 & SAME_HEADER_MASK))
402  {
403  av_log(s, i > 0 ? AV_LOG_INFO : AV_LOG_VERBOSE, "Skipping %d bytes of junk at %"PRId64".\n", i, off);
404  ret = avio_seek(s->pb, off + i, SEEK_SET);
405  if (ret < 0)
406  return ret;
407  break;
408  } else if (ret == CHECK_SEEK_FAILED) {
409  av_log(s, AV_LOG_ERROR, "Invalid frame size (%d): Could not seek to %"PRId64".\n", frame_size, off + i + frame_size);
410  return AVERROR(EINVAL);
411  }
412  } else if (frame_size == CHECK_SEEK_FAILED) {
413  av_log(s, AV_LOG_ERROR, "Failed to read frame size: Could not seek to %"PRId64".\n", (int64_t) (i + 1024 + frame_size + 4));
414  return AVERROR(EINVAL);
415  }
416  ret = avio_seek(s->pb, off, SEEK_SET);
417  if (ret < 0)
418  return ret;
419  }
420 
421  // the seek index is relative to the end of the xing vbr headers
422  for (i = 0; i < st->nb_index_entries; i++)
423  st->index_entries[i].pos += avio_tell(s->pb);
424 
425  /* the parameters will be extracted from the compressed bitstream */
426  return 0;
427 }
428 
429 #define MP3_PACKET_SIZE 1024
430 
432 {
433  MP3DecContext *mp3 = s->priv_data;
434  int ret, size;
435  int64_t pos;
436 
437  size= MP3_PACKET_SIZE;
438  pos = avio_tell(s->pb);
439  if(mp3->filesize > ID3v1_TAG_SIZE && pos < mp3->filesize)
440  size= FFMIN(size, mp3->filesize - pos);
441 
442  ret= av_get_packet(s->pb, pkt, size);
443  if (ret <= 0) {
444  if(ret<0)
445  return ret;
446  return AVERROR_EOF;
447  }
448 
449  pkt->flags &= ~AV_PKT_FLAG_CORRUPT;
450  pkt->stream_index = 0;
451 
452  return ret;
453 }
454 
455 #define SEEK_WINDOW 4096
456 
457 static int check(AVIOContext *pb, int64_t pos, uint32_t *ret_header)
458 {
459  int64_t ret = avio_seek(pb, pos, SEEK_SET);
460  uint8_t header_buf[4];
461  unsigned header;
462  MPADecodeHeader sd;
463  if (ret < 0)
464  return CHECK_SEEK_FAILED;
465 
466  ret = avio_read(pb, &header_buf[0], 4);
467  /* We should always find four bytes for a valid mpa header. */
468  if (ret < 4)
469  return CHECK_SEEK_FAILED;
470 
471  header = AV_RB32(&header_buf[0]);
472  if (ff_mpa_check_header(header) < 0)
473  return CHECK_WRONG_HEADER;
474  if (avpriv_mpegaudio_decode_header(&sd, header) == 1)
475  return CHECK_WRONG_HEADER;
476 
477  if (ret_header)
478  *ret_header = header;
479  return sd.frame_size;
480 }
481 
482 static int64_t mp3_sync(AVFormatContext *s, int64_t target_pos, int flags)
483 {
484  int dir = (flags&AVSEEK_FLAG_BACKWARD) ? -1 : 1;
485  int64_t best_pos;
486  int best_score, i, j;
487  int64_t ret;
488 
489  avio_seek(s->pb, FFMAX(target_pos - SEEK_WINDOW, 0), SEEK_SET);
490  ret = avio_seek(s->pb, target_pos, SEEK_SET);
491  if (ret < 0)
492  return ret;
493 
494 #define MIN_VALID 3
495  best_pos = target_pos;
496  best_score = 999;
497  for(i=0; i<SEEK_WINDOW; i++) {
498  int64_t pos = target_pos + (dir > 0 ? i - SEEK_WINDOW/4 : -i);
499  int64_t candidate = -1;
500  int score = 999;
501 
502  if (pos < 0)
503  continue;
504 
505  for(j=0; j<MIN_VALID; j++) {
506  ret = check(s->pb, pos, NULL);
507  if(ret < 0) {
508  if (ret == CHECK_WRONG_HEADER) {
509  break;
510  } else if (ret == CHECK_SEEK_FAILED) {
511  av_log(s, AV_LOG_ERROR, "Could not seek to %"PRId64".\n", pos);
512  return AVERROR(EINVAL);
513  }
514  }
515  if ((target_pos - pos)*dir <= 0 && FFABS(MIN_VALID/2-j) < score) {
516  candidate = pos;
517  score = FFABS(MIN_VALID/2-j);
518  }
519  pos += ret;
520  }
521  if (best_score > score && j == MIN_VALID) {
522  best_pos = candidate;
523  best_score = score;
524  if(score == 0)
525  break;
526  }
527  }
528 
529  return avio_seek(s->pb, best_pos, SEEK_SET);
530 }
531 
532 static int mp3_seek(AVFormatContext *s, int stream_index, int64_t timestamp,
533  int flags)
534 {
535  MP3DecContext *mp3 = s->priv_data;
536  AVIndexEntry *ie, ie1;
537  AVStream *st = s->streams[0];
538  int64_t best_pos;
539  int fast_seek = s->flags & AVFMT_FLAG_FAST_SEEK;
540  int64_t filesize = mp3->header_filesize;
541 
542  if (filesize <= 0) {
543  int64_t size = avio_size(s->pb);
544  if (size > 0 && size > s->internal->data_offset)
545  filesize = size - s->internal->data_offset;
546  }
547 
548  if (mp3->xing_toc && (mp3->usetoc || (fast_seek && !mp3->is_cbr))) {
549  int64_t ret = av_index_search_timestamp(st, timestamp, flags);
550 
551  // NOTE: The MP3 TOC is not a precise lookup table. Accuracy is worse
552  // for bigger files.
553  av_log(s, AV_LOG_WARNING, "Using MP3 TOC to seek; may be imprecise.\n");
554 
555  if (ret < 0)
556  return ret;
557 
558  ie = &st->index_entries[ret];
559  } else if (fast_seek && st->duration > 0 && filesize > 0) {
560  if (!mp3->is_cbr)
561  av_log(s, AV_LOG_WARNING, "Using scaling to seek VBR MP3; may be imprecise.\n");
562 
563  ie = &ie1;
564  timestamp = av_clip64(timestamp, 0, st->duration);
565  ie->timestamp = timestamp;
566  ie->pos = av_rescale(timestamp, filesize, st->duration) + s->internal->data_offset;
567  } else {
568  return -1; // generic index code
569  }
570 
571  best_pos = mp3_sync(s, ie->pos, flags);
572  if (best_pos < 0)
573  return best_pos;
574 
575  if (mp3->is_cbr && ie == &ie1 && mp3->frames) {
576  int frame_duration = av_rescale(st->duration, 1, mp3->frames);
577  ie1.timestamp = frame_duration * av_rescale(best_pos - s->internal->data_offset, mp3->frames, mp3->header_filesize);
578  }
579 
580  ff_update_cur_dts(s, st, ie->timestamp);
581  return 0;
582 }
583 
584 static const AVOption options[] = {
585  { "usetoc", "use table of contents", offsetof(MP3DecContext, usetoc), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, AV_OPT_FLAG_DECODING_PARAM},
586  { NULL },
587 };
588 
589 static const AVClass demuxer_class = {
590  .class_name = "mp3",
591  .item_name = av_default_item_name,
592  .option = options,
593  .version = LIBAVUTIL_VERSION_INT,
594  .category = AV_CLASS_CATEGORY_DEMUXER,
595 };
596 
598  .name = "mp3",
599  .long_name = NULL_IF_CONFIG_SMALL("MP2/3 (MPEG audio layer 2/3)"),
600  .read_probe = mp3_read_probe,
601  .read_header = mp3_read_header,
602  .read_packet = mp3_read_packet,
603  .read_seek = mp3_seek,
604  .priv_data_size = sizeof(MP3DecContext),
606  .extensions = "mp2,mp3,m2a,mpa", /* XXX: use probe */
607  .priv_class = &demuxer_class,
608 };
#define AVSEEK_FLAG_BACKWARD
Definition: avformat.h:2502
#define NULL
Definition: coverity.c:32
AVDictionary * id3v2_meta
ID3v2 tag useful for MP3 demuxing.
Definition: internal.h:141
Bytestream IO Context.
Definition: avio.h:161
int64_t avio_size(AVIOContext *s)
Get the filesize.
Definition: aviobuf.c:336
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:2038
#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:4827
int64_t pos
Definition: avformat.h:803
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:3884
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:246
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:191
AVIndexEntry * index_entries
Only used if the format does not support seeking natively.
Definition: avformat.h:1103
AVFormatInternal * internal
An opaque field for libavformat internal usage.
Definition: avformat.h:1802
static void read_xing_toc(AVFormatContext *s, int64_t filesize, int64_t duration)
Definition: mp3dec.c:120
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:331
int version
Definition: avisynth_c.h:766
static AVPacket pkt
unsigned int avio_rb16(AVIOContext *s)
Definition: aviobuf.c:786
#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:55
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:1952
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:431
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:801
static int mp3_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
Definition: mp3dec.c:532
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:90
enum AVStreamParseType need_parsing
Definition: avformat.h:1092
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4456
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: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: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:310
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:557
static const uint8_t header[24]
Definition: sdr2.c:67
#define flags(name, subs,...)
Definition: cbs_h2645.c:263
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:797
#define av_log(a,...)
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:648
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:810
#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:1589
int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags)
Get the index for a specific timestamp.
Definition: utils.c:2147
#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:804
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
static int mp3_read_header(AVFormatContext *s)
Definition: mp3dec.c:348
#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:552
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3880
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:1436
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:639
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
#define SEEK_WINDOW
Definition: mp3dec.c:455
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:627
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:794
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:429
#define FFMIN(a, b)
Definition: common.h:96
static int check(AVIOContext *pb, int64_t pos, uint32_t *header)
Definition: mp3dec.c:457
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:145
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:482
#define s(width, name)
Definition: cbs_vp9.c:257
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:613
static void mp3_parse_vbri_tag(AVFormatContext *s, AVStream *st, int64_t base)
Definition: mp3dec.c:283
int frames
Definition: movenc.c:65
#define MIN_VALID
Stream structure.
Definition: avformat.h:874
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:2117
Libavcodec external API header.
AVIOContext * pb
I/O context.
Definition: avformat.h:1393
#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:1105
Describe the class of an AVClass context structure.
Definition: log.h:67
static const AVOption options[]
Definition: mp3dec.c:584
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:470
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:619
#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
int ffio_ensure_seekback(AVIOContext *s, int64_t buf_size)
Ensures that the requested seekback buffer size will be available.
Definition: aviobuf.c:1052
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:923
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:589
int ff_id3v2_match(const uint8_t *buf, const char *magic)
Detect ID3v2 Header.
Definition: id3v2.c:142
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:913
AVInputFormat ff_mp3_demuxer
Definition: mp3dec.c:597
static double c[64]
#define AV_PKT_FLAG_CORRUPT
The packet content is corrupted.
Definition: avcodec.h:1463
#define MKBETAG(a, b, c, d)
Definition: common.h:367
#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:1506
int ff_id3v2_tag_len(const uint8_t *buf)
Get the length of an ID3v2 tag.
Definition: id3v2.c:155
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:305
#define ID3v1_TAG_SIZE
Definition: id3v1.h:27
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:647
#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
Codec parameters associated with this stream.
Definition: avformat.h:1021
static int64_t fsize(FILE *f)
Definition: audiomatch.c:28
int stream_index
Definition: avcodec.h:1432
float min
This structure stores compressed data.
Definition: avcodec.h:1407