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flvdec.c
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1 /*
2  * FLV demuxer
3  * Copyright (c) 2003 The FFmpeg Project
4  *
5  * This demuxer will generate a 1 byte extradata for VP6F content.
6  * It is composed of:
7  * - upper 4bits: difference between encoded width and visible width
8  * - lower 4bits: difference between encoded height and visible height
9  *
10  * This file is part of FFmpeg.
11  *
12  * FFmpeg is free software; you can redistribute it and/or
13  * modify it under the terms of the GNU Lesser General Public
14  * License as published by the Free Software Foundation; either
15  * version 2.1 of the License, or (at your option) any later version.
16  *
17  * FFmpeg is distributed in the hope that it will be useful,
18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
20  * Lesser General Public License for more details.
21  *
22  * You should have received a copy of the GNU Lesser General Public
23  * License along with FFmpeg; if not, write to the Free Software
24  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
25  */
26 
27 #include "libavutil/avstring.h"
29 #include "libavutil/dict.h"
30 #include "libavutil/opt.h"
31 #include "libavutil/intfloat.h"
32 #include "libavutil/mathematics.h"
33 #include "libavcodec/bytestream.h"
34 #include "libavcodec/mpeg4audio.h"
35 #include "avformat.h"
36 #include "internal.h"
37 #include "avio_internal.h"
38 #include "flv.h"
39 
40 #define VALIDATE_INDEX_TS_THRESH 2500
41 
42 typedef struct {
43  const AVClass *class; ///< Class for private options.
44  int trust_metadata; ///< configure streams according onMetaData
45  int wrong_dts; ///< wrong dts due to negative cts
46  uint8_t *new_extradata[FLV_STREAM_TYPE_NB];
47  int new_extradata_size[FLV_STREAM_TYPE_NB];
50  struct {
51  int64_t dts;
52  int64_t pos;
53  } validate_index[2];
57 } FLVContext;
58 
59 static int probe(AVProbeData *p, int live)
60 {
61  const uint8_t *d = p->buf;
62  unsigned offset = AV_RB32(d + 5);
63 
64  if (d[0] == 'F' &&
65  d[1] == 'L' &&
66  d[2] == 'V' &&
67  d[3] < 5 && d[5] == 0 &&
68  offset + 100 < p->buf_size &&
69  offset > 8) {
70  int is_live = !memcmp(d + offset + 40, "NGINX RTMP", 10);
71 
72  if (live == is_live)
73  return AVPROBE_SCORE_MAX;
74  }
75  return 0;
76 }
77 
78 static int flv_probe(AVProbeData *p)
79 {
80  return probe(p, 0);
81 }
82 
84 {
85  return probe(p, 1);
86 }
87 
89 {
90  AVStream *st = avformat_new_stream(s, NULL);
91  if (!st)
92  return NULL;
94  if (s->nb_streams>=3 ||( s->nb_streams==2
98 
99  avpriv_set_pts_info(st, 32, 1, 1000); /* 32 bit pts in ms */
100  return st;
101 }
102 
103 static int flv_same_audio_codec(AVCodecContext *acodec, int flags)
104 {
105  int bits_per_coded_sample = (flags & FLV_AUDIO_SAMPLESIZE_MASK) ? 16 : 8;
106  int flv_codecid = flags & FLV_AUDIO_CODECID_MASK;
107  int codec_id;
108 
109  if (!acodec->codec_id && !acodec->codec_tag)
110  return 1;
111 
112  if (acodec->bits_per_coded_sample != bits_per_coded_sample)
113  return 0;
114 
115  switch (flv_codecid) {
116  // no distinction between S16 and S8 PCM codec flags
117  case FLV_CODECID_PCM:
118  codec_id = bits_per_coded_sample == 8
120 #if HAVE_BIGENDIAN
122 #else
124 #endif
125  return codec_id == acodec->codec_id;
126  case FLV_CODECID_PCM_LE:
127  codec_id = bits_per_coded_sample == 8
130  return codec_id == acodec->codec_id;
131  case FLV_CODECID_AAC:
132  return acodec->codec_id == AV_CODEC_ID_AAC;
133  case FLV_CODECID_ADPCM:
134  return acodec->codec_id == AV_CODEC_ID_ADPCM_SWF;
135  case FLV_CODECID_SPEEX:
136  return acodec->codec_id == AV_CODEC_ID_SPEEX;
137  case FLV_CODECID_MP3:
138  return acodec->codec_id == AV_CODEC_ID_MP3;
142  return acodec->codec_id == AV_CODEC_ID_NELLYMOSER;
144  return acodec->sample_rate == 8000 &&
145  acodec->codec_id == AV_CODEC_ID_PCM_MULAW;
147  return acodec->sample_rate == 8000 &&
148  acodec->codec_id == AV_CODEC_ID_PCM_ALAW;
149  default:
150  return acodec->codec_tag == (flv_codecid >> FLV_AUDIO_CODECID_OFFSET);
151  }
152 }
153 
155  AVCodecContext *acodec, int flv_codecid)
156 {
157  switch (flv_codecid) {
158  // no distinction between S16 and S8 PCM codec flags
159  case FLV_CODECID_PCM:
160  acodec->codec_id = acodec->bits_per_coded_sample == 8
162 #if HAVE_BIGENDIAN
164 #else
166 #endif
167  break;
168  case FLV_CODECID_PCM_LE:
169  acodec->codec_id = acodec->bits_per_coded_sample == 8
172  break;
173  case FLV_CODECID_AAC:
174  acodec->codec_id = AV_CODEC_ID_AAC;
175  break;
176  case FLV_CODECID_ADPCM:
178  break;
179  case FLV_CODECID_SPEEX:
180  acodec->codec_id = AV_CODEC_ID_SPEEX;
181  acodec->sample_rate = 16000;
182  break;
183  case FLV_CODECID_MP3:
184  acodec->codec_id = AV_CODEC_ID_MP3;
186  break;
188  // in case metadata does not otherwise declare samplerate
189  acodec->sample_rate = 8000;
191  break;
193  acodec->sample_rate = 16000;
195  break;
198  break;
200  acodec->sample_rate = 8000;
202  break;
204  acodec->sample_rate = 8000;
205  acodec->codec_id = AV_CODEC_ID_PCM_ALAW;
206  break;
207  default:
208  avpriv_request_sample(s, "Audio codec (%x)",
209  flv_codecid >> FLV_AUDIO_CODECID_OFFSET);
210  acodec->codec_tag = flv_codecid >> FLV_AUDIO_CODECID_OFFSET;
211  }
212 }
213 
214 static int flv_same_video_codec(AVCodecContext *vcodec, int flags)
215 {
216  int flv_codecid = flags & FLV_VIDEO_CODECID_MASK;
217 
218  if (!vcodec->codec_id && !vcodec->codec_tag)
219  return 1;
220 
221  switch (flv_codecid) {
222  case FLV_CODECID_H263:
223  return vcodec->codec_id == AV_CODEC_ID_FLV1;
224  case FLV_CODECID_SCREEN:
225  return vcodec->codec_id == AV_CODEC_ID_FLASHSV;
226  case FLV_CODECID_SCREEN2:
227  return vcodec->codec_id == AV_CODEC_ID_FLASHSV2;
228  case FLV_CODECID_VP6:
229  return vcodec->codec_id == AV_CODEC_ID_VP6F;
230  case FLV_CODECID_VP6A:
231  return vcodec->codec_id == AV_CODEC_ID_VP6A;
232  case FLV_CODECID_H264:
233  return vcodec->codec_id == AV_CODEC_ID_H264;
234  default:
235  return vcodec->codec_tag == flv_codecid;
236  }
237 }
238 
240  int flv_codecid, int read)
241 {
242  AVCodecContext *vcodec = vstream->codec;
243  switch (flv_codecid) {
244  case FLV_CODECID_H263:
245  vcodec->codec_id = AV_CODEC_ID_FLV1;
246  break;
248  vcodec->codec_id = AV_CODEC_ID_H263;
249  break; // Really mean it this time
250  case FLV_CODECID_SCREEN:
251  vcodec->codec_id = AV_CODEC_ID_FLASHSV;
252  break;
253  case FLV_CODECID_SCREEN2:
254  vcodec->codec_id = AV_CODEC_ID_FLASHSV2;
255  break;
256  case FLV_CODECID_VP6:
257  vcodec->codec_id = AV_CODEC_ID_VP6F;
258  case FLV_CODECID_VP6A:
259  if (flv_codecid == FLV_CODECID_VP6A)
260  vcodec->codec_id = AV_CODEC_ID_VP6A;
261  if (read) {
262  if (vcodec->extradata_size != 1) {
263  ff_alloc_extradata(vcodec, 1);
264  }
265  if (vcodec->extradata)
266  vcodec->extradata[0] = avio_r8(s->pb);
267  else
268  avio_skip(s->pb, 1);
269  }
270  return 1; // 1 byte body size adjustment for flv_read_packet()
271  case FLV_CODECID_H264:
272  vcodec->codec_id = AV_CODEC_ID_H264;
274  return 3; // not 4, reading packet type will consume one byte
275  case FLV_CODECID_MPEG4:
276  vcodec->codec_id = AV_CODEC_ID_MPEG4;
277  return 3;
278  default:
279  avpriv_request_sample(s, "Video codec (%x)", flv_codecid);
280  vcodec->codec_tag = flv_codecid;
281  }
282 
283  return 0;
284 }
285 
286 static int amf_get_string(AVIOContext *ioc, char *buffer, int buffsize)
287 {
288  int length = avio_rb16(ioc);
289  if (length >= buffsize) {
290  avio_skip(ioc, length);
291  return -1;
292  }
293 
294  avio_read(ioc, buffer, length);
295 
296  buffer[length] = '\0';
297 
298  return length;
299 }
300 
302  AVStream *vstream, int64_t max_pos)
303 {
304  FLVContext *flv = s->priv_data;
305  unsigned int timeslen = 0, fileposlen = 0, i;
306  char str_val[256];
307  int64_t *times = NULL;
308  int64_t *filepositions = NULL;
309  int ret = AVERROR(ENOSYS);
310  int64_t initial_pos = avio_tell(ioc);
311 
312  if (vstream->nb_index_entries>0) {
313  av_log(s, AV_LOG_WARNING, "Skipping duplicate index\n");
314  return 0;
315  }
316 
317  if (s->flags & AVFMT_FLAG_IGNIDX)
318  return 0;
319 
320  while (avio_tell(ioc) < max_pos - 2 &&
321  amf_get_string(ioc, str_val, sizeof(str_val)) > 0) {
322  int64_t **current_array;
323  unsigned int arraylen;
324 
325  // Expect array object in context
326  if (avio_r8(ioc) != AMF_DATA_TYPE_ARRAY)
327  break;
328 
329  arraylen = avio_rb32(ioc);
330  if (arraylen>>28)
331  break;
332 
333  if (!strcmp(KEYFRAMES_TIMESTAMP_TAG , str_val) && !times) {
334  current_array = &times;
335  timeslen = arraylen;
336  } else if (!strcmp(KEYFRAMES_BYTEOFFSET_TAG, str_val) &&
337  !filepositions) {
338  current_array = &filepositions;
339  fileposlen = arraylen;
340  } else
341  // unexpected metatag inside keyframes, will not use such
342  // metadata for indexing
343  break;
344 
345  if (!(*current_array = av_mallocz(sizeof(**current_array) * arraylen))) {
346  ret = AVERROR(ENOMEM);
347  goto finish;
348  }
349 
350  for (i = 0; i < arraylen && avio_tell(ioc) < max_pos - 1; i++) {
351  if (avio_r8(ioc) != AMF_DATA_TYPE_NUMBER)
352  goto invalid;
353  current_array[0][i] = av_int2double(avio_rb64(ioc));
354  }
355  if (times && filepositions) {
356  // All done, exiting at a position allowing amf_parse_object
357  // to finish parsing the object
358  ret = 0;
359  break;
360  }
361  }
362 
363  if (timeslen == fileposlen && fileposlen>1 && max_pos <= filepositions[0]) {
364  for (i = 0; i < fileposlen; i++) {
365  av_add_index_entry(vstream, filepositions[i], times[i] * 1000,
366  0, 0, AVINDEX_KEYFRAME);
367  if (i < 2) {
368  flv->validate_index[i].pos = filepositions[i];
369  flv->validate_index[i].dts = times[i] * 1000;
370  flv->validate_count = i + 1;
371  }
372  }
373  } else {
374 invalid:
375  av_log(s, AV_LOG_WARNING, "Invalid keyframes object, skipping.\n");
376  }
377 
378 finish:
379  av_freep(&times);
380  av_freep(&filepositions);
381  avio_seek(ioc, initial_pos, SEEK_SET);
382  return ret;
383 }
384 
386  AVStream *vstream, const char *key,
387  int64_t max_pos, int depth)
388 {
389  AVCodecContext *acodec, *vcodec;
390  FLVContext *flv = s->priv_data;
391  AVIOContext *ioc;
392  AMFDataType amf_type;
393  char str_val[256];
394  double num_val;
395 
396  num_val = 0;
397  ioc = s->pb;
398  amf_type = avio_r8(ioc);
399 
400  switch (amf_type) {
402  num_val = av_int2double(avio_rb64(ioc));
403  break;
404  case AMF_DATA_TYPE_BOOL:
405  num_val = avio_r8(ioc);
406  break;
408  if (amf_get_string(ioc, str_val, sizeof(str_val)) < 0)
409  return -1;
410  break;
412  if ((vstream || astream) && key &&
413  ioc->seekable &&
414  !strcmp(KEYFRAMES_TAG, key) && depth == 1)
415  if (parse_keyframes_index(s, ioc, vstream ? vstream : astream,
416  max_pos) < 0)
417  av_log(s, AV_LOG_ERROR, "Keyframe index parsing failed\n");
418 
419  while (avio_tell(ioc) < max_pos - 2 &&
420  amf_get_string(ioc, str_val, sizeof(str_val)) > 0)
421  if (amf_parse_object(s, astream, vstream, str_val, max_pos,
422  depth + 1) < 0)
423  return -1; // if we couldn't skip, bomb out.
424  if (avio_r8(ioc) != AMF_END_OF_OBJECT)
425  return -1;
426  break;
427  case AMF_DATA_TYPE_NULL:
430  break; // these take up no additional space
432  avio_skip(ioc, 4); // skip 32-bit max array index
433  while (avio_tell(ioc) < max_pos - 2 &&
434  amf_get_string(ioc, str_val, sizeof(str_val)) > 0)
435  // this is the only case in which we would want a nested
436  // parse to not skip over the object
437  if (amf_parse_object(s, astream, vstream, str_val, max_pos,
438  depth + 1) < 0)
439  return -1;
440  if (avio_r8(ioc) != AMF_END_OF_OBJECT)
441  return -1;
442  break;
443  case AMF_DATA_TYPE_ARRAY:
444  {
445  unsigned int arraylen, i;
446 
447  arraylen = avio_rb32(ioc);
448  for (i = 0; i < arraylen && avio_tell(ioc) < max_pos - 1; i++)
449  if (amf_parse_object(s, NULL, NULL, NULL, max_pos,
450  depth + 1) < 0)
451  return -1; // if we couldn't skip, bomb out.
452  }
453  break;
454  case AMF_DATA_TYPE_DATE:
455  avio_skip(ioc, 8 + 2); // timestamp (double) and UTC offset (int16)
456  break;
457  default: // unsupported type, we couldn't skip
458  return -1;
459  }
460 
461  if (key) {
462  acodec = astream ? astream->codec : NULL;
463  vcodec = vstream ? vstream->codec : NULL;
464 
465  // stream info doesn't live any deeper than the first object
466  if (depth == 1) {
467  if (amf_type == AMF_DATA_TYPE_NUMBER ||
468  amf_type == AMF_DATA_TYPE_BOOL) {
469  if (!strcmp(key, "duration"))
470  s->duration = num_val * AV_TIME_BASE;
471  else if (!strcmp(key, "videodatarate") && vcodec &&
472  0 <= (int)(num_val * 1024.0))
473  vcodec->bit_rate = num_val * 1024.0;
474  else if (!strcmp(key, "audiodatarate") && acodec &&
475  0 <= (int)(num_val * 1024.0))
476  acodec->bit_rate = num_val * 1024.0;
477  else if (!strcmp(key, "datastream")) {
479  if (!st)
480  return AVERROR(ENOMEM);
482  } else if (flv->trust_metadata) {
483  if (!strcmp(key, "videocodecid") && vcodec) {
484  flv_set_video_codec(s, vstream, num_val, 0);
485  } else if (!strcmp(key, "audiocodecid") && acodec) {
486  int id = ((int)num_val) << FLV_AUDIO_CODECID_OFFSET;
487  flv_set_audio_codec(s, astream, acodec, id);
488  } else if (!strcmp(key, "audiosamplerate") && acodec) {
489  acodec->sample_rate = num_val;
490  } else if (!strcmp(key, "audiosamplesize") && acodec) {
491  acodec->bits_per_coded_sample = num_val;
492  } else if (!strcmp(key, "stereo") && acodec) {
493  acodec->channels = num_val + 1;
494  acodec->channel_layout = acodec->channels == 2 ?
497  } else if (!strcmp(key, "width") && vcodec) {
498  vcodec->width = num_val;
499  } else if (!strcmp(key, "height") && vcodec) {
500  vcodec->height = num_val;
501  }
502  }
503  }
504  }
505 
506  if (amf_type == AMF_DATA_TYPE_OBJECT && s->nb_streams == 1 &&
507  ((!acodec && !strcmp(key, "audiocodecid")) ||
508  (!vcodec && !strcmp(key, "videocodecid"))))
509  s->ctx_flags &= ~AVFMTCTX_NOHEADER; //If there is either audio/video missing, codecid will be an empty object
510 
511  if (!strcmp(key, "duration") ||
512  !strcmp(key, "filesize") ||
513  !strcmp(key, "width") ||
514  !strcmp(key, "height") ||
515  !strcmp(key, "videodatarate") ||
516  !strcmp(key, "framerate") ||
517  !strcmp(key, "videocodecid") ||
518  !strcmp(key, "audiodatarate") ||
519  !strcmp(key, "audiosamplerate") ||
520  !strcmp(key, "audiosamplesize") ||
521  !strcmp(key, "stereo") ||
522  !strcmp(key, "audiocodecid") ||
523  !strcmp(key, "datastream"))
524  return 0;
525 
527  if (amf_type == AMF_DATA_TYPE_BOOL) {
528  av_strlcpy(str_val, num_val > 0 ? "true" : "false",
529  sizeof(str_val));
530  av_dict_set(&s->metadata, key, str_val, 0);
531  } else if (amf_type == AMF_DATA_TYPE_NUMBER) {
532  snprintf(str_val, sizeof(str_val), "%.f", num_val);
533  av_dict_set(&s->metadata, key, str_val, 0);
534  } else if (amf_type == AMF_DATA_TYPE_STRING)
535  av_dict_set(&s->metadata, key, str_val, 0);
536  }
537 
538  return 0;
539 }
540 
541 static int flv_read_metabody(AVFormatContext *s, int64_t next_pos)
542 {
544  AVStream *stream, *astream, *vstream;
545  AVStream av_unused *dstream;
546  AVIOContext *ioc;
547  int i;
548  // only needs to hold the string "onMetaData".
549  // Anything longer is something we don't want.
550  char buffer[11];
551 
552  astream = NULL;
553  vstream = NULL;
554  dstream = NULL;
555  ioc = s->pb;
556 
557  // first object needs to be "onMetaData" string
558  type = avio_r8(ioc);
559  if (type != AMF_DATA_TYPE_STRING ||
560  amf_get_string(ioc, buffer, sizeof(buffer)) < 0)
561  return -1;
562 
563  if (!strcmp(buffer, "onTextData"))
564  return 1;
565 
566  if (strcmp(buffer, "onMetaData") && strcmp(buffer, "onCuePoint"))
567  return -1;
568 
569  // find the streams now so that amf_parse_object doesn't need to do
570  // the lookup every time it is called.
571  for (i = 0; i < s->nb_streams; i++) {
572  stream = s->streams[i];
573  if (stream->codec->codec_type == AVMEDIA_TYPE_VIDEO)
574  vstream = stream;
575  else if (stream->codec->codec_type == AVMEDIA_TYPE_AUDIO)
576  astream = stream;
577  else if (stream->codec->codec_type == AVMEDIA_TYPE_DATA)
578  dstream = stream;
579  }
580 
581  // parse the second object (we want a mixed array)
582  if (amf_parse_object(s, astream, vstream, buffer, next_pos, 0) < 0)
583  return -1;
584 
585  return 0;
586 }
587 
589 {
590  int offset, flags;
591 
592  avio_skip(s->pb, 4);
593  flags = avio_r8(s->pb);
594 
596 
597  if (flags & FLV_HEADER_FLAG_HASVIDEO)
599  return AVERROR(ENOMEM);
600  if (flags & FLV_HEADER_FLAG_HASAUDIO)
602  return AVERROR(ENOMEM);
603  // Flag doesn't indicate whether or not there is script-data present. Must
604  // create that stream if it's encountered.
605 
606  offset = avio_rb32(s->pb);
607  avio_seek(s->pb, offset, SEEK_SET);
608  avio_skip(s->pb, 4);
609 
610  s->start_time = 0;
611 
612  return 0;
613 }
614 
616 {
617  int i;
618  FLVContext *flv = s->priv_data;
619  for (i=0; i<FLV_STREAM_TYPE_NB; i++)
620  av_freep(&flv->new_extradata[i]);
621  return 0;
622 }
623 
625 {
626  av_freep(&st->codec->extradata);
627  if (ff_get_extradata(st->codec, s->pb, size) < 0)
628  return AVERROR(ENOMEM);
629  return 0;
630 }
631 
632 static int flv_queue_extradata(FLVContext *flv, AVIOContext *pb, int stream,
633  int size)
634 {
635  av_free(flv->new_extradata[stream]);
636  flv->new_extradata[stream] = av_mallocz(size +
638  if (!flv->new_extradata[stream])
639  return AVERROR(ENOMEM);
640  flv->new_extradata_size[stream] = size;
641  avio_read(pb, flv->new_extradata[stream], size);
642  return 0;
643 }
644 
645 static void clear_index_entries(AVFormatContext *s, int64_t pos)
646 {
647  int i, j, out;
649  "Found invalid index entries, clearing the index.\n");
650  for (i = 0; i < s->nb_streams; i++) {
651  AVStream *st = s->streams[i];
652  /* Remove all index entries that point to >= pos */
653  out = 0;
654  for (j = 0; j < st->nb_index_entries; j++)
655  if (st->index_entries[j].pos < pos)
656  st->index_entries[out++] = st->index_entries[j];
657  st->nb_index_entries = out;
658  }
659 }
660 
662 {
663  int nb = -1, ret, parse_name = 1;
664 
665  switch (type) {
667  avio_skip(pb, 8);
668  break;
669  case AMF_DATA_TYPE_BOOL:
670  avio_skip(pb, 1);
671  break;
673  avio_skip(pb, avio_rb16(pb));
674  break;
675  case AMF_DATA_TYPE_ARRAY:
676  parse_name = 0;
678  nb = avio_rb32(pb);
680  while(!pb->eof_reached && (nb-- > 0 || type != AMF_DATA_TYPE_ARRAY)) {
681  if (parse_name) {
682  int size = avio_rb16(pb);
683  if (!size) {
684  avio_skip(pb, 1);
685  break;
686  }
687  avio_skip(pb, size);
688  }
689  if ((ret = amf_skip_tag(pb, avio_r8(pb))) < 0)
690  return ret;
691  }
692  break;
693  case AMF_DATA_TYPE_NULL:
695  break;
696  default:
697  return AVERROR_INVALIDDATA;
698  }
699  return 0;
700 }
701 
703  int64_t dts, int64_t next)
704 {
705  AVIOContext *pb = s->pb;
706  AVStream *st = NULL;
707  char buf[20];
708  int ret = AVERROR_INVALIDDATA;
709  int i, length = -1;
710 
711  switch (avio_r8(pb)) {
713  avio_seek(pb, 4, SEEK_CUR);
715  break;
716  default:
717  goto skip;
718  }
719 
720  while ((ret = amf_get_string(pb, buf, sizeof(buf))) > 0) {
721  AMFDataType type = avio_r8(pb);
722  if (type == AMF_DATA_TYPE_STRING && !strcmp(buf, "text")) {
723  length = avio_rb16(pb);
724  ret = av_get_packet(pb, pkt, length);
725  if (ret < 0)
726  goto skip;
727  else
728  break;
729  } else {
730  if ((ret = amf_skip_tag(pb, type)) < 0)
731  goto skip;
732  }
733  }
734 
735  if (length < 0) {
736  ret = AVERROR_INVALIDDATA;
737  goto skip;
738  }
739 
740  for (i = 0; i < s->nb_streams; i++) {
741  st = s->streams[i];
742  if (st->codec->codec_type == AVMEDIA_TYPE_DATA)
743  break;
744  }
745 
746  if (i == s->nb_streams) {
748  if (!st)
749  return AVERROR(ENOMEM);
751  }
752 
753  pkt->dts = dts;
754  pkt->pts = dts;
755  pkt->size = ret;
756 
757  pkt->stream_index = st->index;
758  pkt->flags |= AV_PKT_FLAG_KEY;
759 
760 skip:
761  avio_seek(s->pb, next + 4, SEEK_SET);
762 
763  return ret;
764 }
765 
767 {
768  FLVContext *flv = s->priv_data;
769  int ret, i, type, size, flags;
770  int stream_type=-1;
771  int64_t next, pos, meta_pos;
772  int64_t dts, pts = AV_NOPTS_VALUE;
773  int av_uninit(channels);
774  int av_uninit(sample_rate);
775  AVStream *st = NULL;
776 
777  /* pkt size is repeated at end. skip it */
778  for (;; avio_skip(s->pb, 4)) {
779  pos = avio_tell(s->pb);
780  type = (avio_r8(s->pb) & 0x1F);
781  size = avio_rb24(s->pb);
782  dts = avio_rb24(s->pb);
783  dts |= avio_r8(s->pb) << 24;
784  av_dlog(s, "type:%d, size:%d, dts:%"PRId64" pos:%"PRId64"\n", type, size, dts, avio_tell(s->pb));
785  if (avio_feof(s->pb))
786  return AVERROR_EOF;
787  avio_skip(s->pb, 3); /* stream id, always 0 */
788  flags = 0;
789 
790  if (flv->validate_next < flv->validate_count) {
791  int64_t validate_pos = flv->validate_index[flv->validate_next].pos;
792  if (pos == validate_pos) {
793  if (FFABS(dts - flv->validate_index[flv->validate_next].dts) <=
795  flv->validate_next++;
796  } else {
797  clear_index_entries(s, validate_pos);
798  flv->validate_count = 0;
799  }
800  } else if (pos > validate_pos) {
801  clear_index_entries(s, validate_pos);
802  flv->validate_count = 0;
803  }
804  }
805 
806  if (size == 0)
807  continue;
808 
809  next = size + avio_tell(s->pb);
810 
811  if (type == FLV_TAG_TYPE_AUDIO) {
812  stream_type = FLV_STREAM_TYPE_AUDIO;
813  flags = avio_r8(s->pb);
814  size--;
815  } else if (type == FLV_TAG_TYPE_VIDEO) {
816  stream_type = FLV_STREAM_TYPE_VIDEO;
817  flags = avio_r8(s->pb);
818  size--;
820  goto skip;
821  } else if (type == FLV_TAG_TYPE_META) {
822  stream_type=FLV_STREAM_TYPE_DATA;
823  if (size > 13 + 1 + 4 && dts == 0) { // Header-type metadata stuff
824  meta_pos = avio_tell(s->pb);
825  if (flv_read_metabody(s, next) == 0) {
826  goto skip;
827  }
828  avio_seek(s->pb, meta_pos, SEEK_SET);
829  }
830  } else {
831  av_log(s, AV_LOG_DEBUG,
832  "Skipping flv packet: type %d, size %d, flags %d.\n",
833  type, size, flags);
834 skip:
835  avio_seek(s->pb, next, SEEK_SET);
836  continue;
837  }
838 
839  /* skip empty data packets */
840  if (!size)
841  continue;
842 
843  /* now find stream */
844  for (i = 0; i < s->nb_streams; i++) {
845  st = s->streams[i];
846  if (stream_type == FLV_STREAM_TYPE_AUDIO) {
847  if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO &&
848  (s->audio_codec_id || flv_same_audio_codec(st->codec, flags)))
849  break;
850  } else if (stream_type == FLV_STREAM_TYPE_VIDEO) {
851  if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO &&
852  (s->video_codec_id || flv_same_video_codec(st->codec, flags)))
853  break;
854  } else if (stream_type == FLV_STREAM_TYPE_DATA) {
855  if (st->codec->codec_type == AVMEDIA_TYPE_DATA)
856  break;
857  }
858  }
859  if (i == s->nb_streams) {
860  static const enum AVMediaType stream_types[] = {AVMEDIA_TYPE_VIDEO, AVMEDIA_TYPE_AUDIO, AVMEDIA_TYPE_DATA};
861  av_log(s, AV_LOG_WARNING, "Stream discovered after head already parsed\n");
862  st = create_stream(s, stream_types[stream_type]);
863  if (!st)
864  return AVERROR(ENOMEM);
865 
866  }
867  av_dlog(s, "%d %X %d \n", stream_type, flags, st->discard);
868 
869  if ((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_KEY ||
870  stream_type == FLV_STREAM_TYPE_AUDIO)
871  av_add_index_entry(st, pos, dts, size, 0, AVINDEX_KEYFRAME);
872 
873  if ( (st->discard >= AVDISCARD_NONKEY && !((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_KEY || (stream_type == FLV_STREAM_TYPE_AUDIO)))
874  ||(st->discard >= AVDISCARD_BIDIR && ((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_DISP_INTER && (stream_type == FLV_STREAM_TYPE_VIDEO)))
875  || st->discard >= AVDISCARD_ALL
876  ) {
877  avio_seek(s->pb, next, SEEK_SET);
878  continue;
879  }
880  break;
881  }
882 
883  // if not streamed and no duration from metadata then seek to end to find
884  // the duration from the timestamps
885  if (s->pb->seekable && (!s->duration || s->duration == AV_NOPTS_VALUE) && !flv->searched_for_end) {
886  int size;
887  const int64_t pos = avio_tell(s->pb);
888  // Read the last 4 bytes of the file, this should be the size of the
889  // previous FLV tag. Use the timestamp of its payload as duration.
890  int64_t fsize = avio_size(s->pb);
891 retry_duration:
892  avio_seek(s->pb, fsize - 4, SEEK_SET);
893  size = avio_rb32(s->pb);
894  // Seek to the start of the last FLV tag at position (fsize - 4 - size)
895  // but skip the byte indicating the type.
896  avio_seek(s->pb, fsize - 3 - size, SEEK_SET);
897  if (size == avio_rb24(s->pb) + 11) {
898  uint32_t ts = avio_rb24(s->pb);
899  ts |= avio_r8(s->pb) << 24;
900  if (ts)
901  s->duration = ts * (int64_t)AV_TIME_BASE / 1000;
902  else if (fsize >= 8 && fsize - 8 >= size) {
903  fsize -= size+4;
904  goto retry_duration;
905  }
906  }
907 
908  avio_seek(s->pb, pos, SEEK_SET);
909  flv->searched_for_end = 1;
910  }
911 
912  if (stream_type == FLV_STREAM_TYPE_AUDIO) {
913  int bits_per_coded_sample;
914  channels = (flags & FLV_AUDIO_CHANNEL_MASK) == FLV_STEREO ? 2 : 1;
915  sample_rate = 44100 << ((flags & FLV_AUDIO_SAMPLERATE_MASK) >>
917  bits_per_coded_sample = (flags & FLV_AUDIO_SAMPLESIZE_MASK) ? 16 : 8;
918  if (!st->codec->channels || !st->codec->sample_rate ||
920  st->codec->channels = channels;
921  st->codec->channel_layout = channels == 1
925  st->codec->bits_per_coded_sample = bits_per_coded_sample;
926  }
927  if (!st->codec->codec_id) {
928  flv_set_audio_codec(s, st, st->codec,
929  flags & FLV_AUDIO_CODECID_MASK);
930  flv->last_sample_rate =
932  flv->last_channels =
933  channels = st->codec->channels;
934  } else {
935  AVCodecContext ctx = {0};
936  ctx.sample_rate = sample_rate;
937  ctx.bits_per_coded_sample = bits_per_coded_sample;
938  flv_set_audio_codec(s, st, &ctx, flags & FLV_AUDIO_CODECID_MASK);
939  sample_rate = ctx.sample_rate;
940  }
941  } else if (stream_type == FLV_STREAM_TYPE_VIDEO) {
942  size -= flv_set_video_codec(s, st, flags & FLV_VIDEO_CODECID_MASK, 1);
943  }
944 
945  if (st->codec->codec_id == AV_CODEC_ID_AAC ||
946  st->codec->codec_id == AV_CODEC_ID_H264 ||
947  st->codec->codec_id == AV_CODEC_ID_MPEG4) {
948  int type = avio_r8(s->pb);
949  size--;
951  // sign extension
952  int32_t cts = (avio_rb24(s->pb) + 0xff800000) ^ 0xff800000;
953  pts = dts + cts;
954  if (cts < 0) { // dts might be wrong
955  if (!flv->wrong_dts)
957  "Negative cts, previous timestamps might be wrong.\n");
958  flv->wrong_dts = 1;
959  } else if (FFABS(dts - pts) > 1000*60*15) {
961  "invalid timestamps %"PRId64" %"PRId64"\n", dts, pts);
962  dts = pts = AV_NOPTS_VALUE;
963  }
964  }
965  if (type == 0 && (!st->codec->extradata || st->codec->codec_id == AV_CODEC_ID_AAC ||
966  st->codec->codec_id == AV_CODEC_ID_H264)) {
968 
969  if (st->codec->extradata) {
970  if ((ret = flv_queue_extradata(flv, s->pb, stream_type, size)) < 0)
971  return ret;
972  ret = AVERROR(EAGAIN);
973  goto leave;
974  }
975  if ((ret = flv_get_extradata(s, st, size)) < 0)
976  return ret;
977 
978  /* Workaround for buggy Omnia A/XE encoder */
979  t = av_dict_get(s->metadata, "Encoder", NULL, 0);
980  if (st->codec->codec_id == AV_CODEC_ID_AAC && t && !strcmp(t->value, "Omnia A/XE"))
981  st->codec->extradata_size = 2;
982 
983  if (st->codec->codec_id == AV_CODEC_ID_AAC && 0) {
984  MPEG4AudioConfig cfg;
985 
987  st->codec->extradata_size * 8, 1) >= 0) {
988  st->codec->channels = cfg.channels;
989  st->codec->channel_layout = 0;
990  if (cfg.ext_sample_rate)
991  st->codec->sample_rate = cfg.ext_sample_rate;
992  else
993  st->codec->sample_rate = cfg.sample_rate;
994  av_dlog(s, "mp4a config channels %d sample rate %d\n",
995  st->codec->channels, st->codec->sample_rate);
996  }
997  }
998 
999  ret = AVERROR(EAGAIN);
1000  goto leave;
1001  }
1002  }
1003 
1004  /* skip empty data packets */
1005  if (!size) {
1006  ret = AVERROR(EAGAIN);
1007  goto leave;
1008  }
1009 
1010  ret = av_get_packet(s->pb, pkt, size);
1011  if (ret < 0)
1012  return ret;
1013  pkt->dts = dts;
1014  pkt->pts = pts == AV_NOPTS_VALUE ? dts : pts;
1015  pkt->stream_index = st->index;
1016  if (flv->new_extradata[stream_type]) {
1018  flv->new_extradata_size[stream_type]);
1019  if (side) {
1020  memcpy(side, flv->new_extradata[stream_type],
1021  flv->new_extradata_size[stream_type]);
1022  av_freep(&flv->new_extradata[stream_type]);
1023  flv->new_extradata_size[stream_type] = 0;
1024  }
1025  }
1026  if (stream_type == FLV_STREAM_TYPE_AUDIO &&
1027  (sample_rate != flv->last_sample_rate ||
1028  channels != flv->last_channels)) {
1030  flv->last_channels = channels;
1031  ff_add_param_change(pkt, channels, 0, sample_rate, 0, 0);
1032  }
1033 
1034  if ( stream_type == FLV_STREAM_TYPE_AUDIO ||
1035  ((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_KEY) ||
1036  stream_type == FLV_STREAM_TYPE_DATA)
1037  pkt->flags |= AV_PKT_FLAG_KEY;
1038 
1039 leave:
1040  avio_skip(s->pb, 4);
1041  return ret;
1042 }
1043 
1044 static int flv_read_seek(AVFormatContext *s, int stream_index,
1045  int64_t ts, int flags)
1046 {
1047  FLVContext *flv = s->priv_data;
1048  flv->validate_count = 0;
1049  return avio_seek_time(s->pb, stream_index, ts, flags);
1050 }
1051 
1052 #define OFFSET(x) offsetof(FLVContext, x)
1053 #define VD AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_DECODING_PARAM
1054 static const AVOption options[] = {
1055  { "flv_metadata", "Allocate streams according to the onMetaData array", OFFSET(trust_metadata), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, VD },
1056  { NULL }
1057 };
1058 
1059 static const AVClass flv_class = {
1060  .class_name = "flvdec",
1061  .item_name = av_default_item_name,
1062  .option = options,
1063  .version = LIBAVUTIL_VERSION_INT,
1064 };
1065 
1067  .name = "flv",
1068  .long_name = NULL_IF_CONFIG_SMALL("FLV (Flash Video)"),
1069  .priv_data_size = sizeof(FLVContext),
1070  .read_probe = flv_probe,
1075  .extensions = "flv",
1076  .priv_class = &flv_class,
1077 };
1078 
1079 static const AVClass live_flv_class = {
1080  .class_name = "live_flvdec",
1081  .item_name = av_default_item_name,
1082  .option = options,
1083  .version = LIBAVUTIL_VERSION_INT,
1084 };
1085 
1087  .name = "live_flv",
1088  .long_name = NULL_IF_CONFIG_SMALL("live RTMP FLV (Flash Video)"),
1089  .priv_data_size = sizeof(FLVContext),
1095  .extensions = "flv",
1096  .priv_class = &live_flv_class,
1098 };