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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  // only look for metadata values when we are not nested and key != NULL
462  if (depth == 1 && key) {
463  acodec = astream ? astream->codec : NULL;
464  vcodec = vstream ? vstream->codec : NULL;
465 
466  if (amf_type == AMF_DATA_TYPE_NUMBER ||
467  amf_type == AMF_DATA_TYPE_BOOL) {
468  if (!strcmp(key, "duration"))
469  s->duration = num_val * AV_TIME_BASE;
470  else if (!strcmp(key, "videodatarate") && vcodec &&
471  0 <= (int)(num_val * 1024.0))
472  vcodec->bit_rate = num_val * 1024.0;
473  else if (!strcmp(key, "audiodatarate") && acodec &&
474  0 <= (int)(num_val * 1024.0))
475  acodec->bit_rate = num_val * 1024.0;
476  else if (!strcmp(key, "datastream")) {
478  if (!st)
479  return AVERROR(ENOMEM);
481  } else if (flv->trust_metadata) {
482  if (!strcmp(key, "videocodecid") && vcodec) {
483  flv_set_video_codec(s, vstream, num_val, 0);
484  } else if (!strcmp(key, "audiocodecid") && acodec) {
485  int id = ((int)num_val) << FLV_AUDIO_CODECID_OFFSET;
486  flv_set_audio_codec(s, astream, acodec, id);
487  } else if (!strcmp(key, "audiosamplerate") && acodec) {
488  acodec->sample_rate = num_val;
489  } else if (!strcmp(key, "audiosamplesize") && acodec) {
490  acodec->bits_per_coded_sample = num_val;
491  } else if (!strcmp(key, "stereo") && acodec) {
492  acodec->channels = num_val + 1;
493  acodec->channel_layout = acodec->channels == 2 ?
496  } else if (!strcmp(key, "width") && vcodec) {
497  vcodec->width = num_val;
498  } else if (!strcmp(key, "height") && vcodec) {
499  vcodec->height = num_val;
500  }
501  }
502  }
503 
504  if (amf_type == AMF_DATA_TYPE_OBJECT && s->nb_streams == 1 &&
505  ((!acodec && !strcmp(key, "audiocodecid")) ||
506  (!vcodec && !strcmp(key, "videocodecid"))))
507  s->ctx_flags &= ~AVFMTCTX_NOHEADER; //If there is either audio/video missing, codecid will be an empty object
508 
509  if (!strcmp(key, "duration") ||
510  !strcmp(key, "filesize") ||
511  !strcmp(key, "width") ||
512  !strcmp(key, "height") ||
513  !strcmp(key, "videodatarate") ||
514  !strcmp(key, "framerate") ||
515  !strcmp(key, "videocodecid") ||
516  !strcmp(key, "audiodatarate") ||
517  !strcmp(key, "audiosamplerate") ||
518  !strcmp(key, "audiosamplesize") ||
519  !strcmp(key, "stereo") ||
520  !strcmp(key, "audiocodecid") ||
521  !strcmp(key, "datastream"))
522  return 0;
523 
524  if (amf_type == AMF_DATA_TYPE_BOOL) {
525  av_strlcpy(str_val, num_val > 0 ? "true" : "false",
526  sizeof(str_val));
527  av_dict_set(&s->metadata, key, str_val, 0);
528  } else if (amf_type == AMF_DATA_TYPE_NUMBER) {
529  snprintf(str_val, sizeof(str_val), "%.f", num_val);
530  av_dict_set(&s->metadata, key, str_val, 0);
531  } else if (amf_type == AMF_DATA_TYPE_STRING)
532  av_dict_set(&s->metadata, key, str_val, 0);
533  }
534 
535  return 0;
536 }
537 
538 static int flv_read_metabody(AVFormatContext *s, int64_t next_pos)
539 {
541  AVStream *stream, *astream, *vstream;
542  AVStream av_unused *dstream;
543  AVIOContext *ioc;
544  int i;
545  // only needs to hold the string "onMetaData".
546  // Anything longer is something we don't want.
547  char buffer[11];
548 
549  astream = NULL;
550  vstream = NULL;
551  dstream = NULL;
552  ioc = s->pb;
553 
554  // first object needs to be "onMetaData" string
555  type = avio_r8(ioc);
556  if (type != AMF_DATA_TYPE_STRING ||
557  amf_get_string(ioc, buffer, sizeof(buffer)) < 0)
558  return -1;
559 
560  if (!strcmp(buffer, "onTextData"))
561  return 1;
562 
563  if (strcmp(buffer, "onMetaData"))
564  return -1;
565 
566  // find the streams now so that amf_parse_object doesn't need to do
567  // the lookup every time it is called.
568  for (i = 0; i < s->nb_streams; i++) {
569  stream = s->streams[i];
570  if (stream->codec->codec_type == AVMEDIA_TYPE_VIDEO)
571  vstream = stream;
572  else if (stream->codec->codec_type == AVMEDIA_TYPE_AUDIO)
573  astream = stream;
574  else if (stream->codec->codec_type == AVMEDIA_TYPE_DATA)
575  dstream = stream;
576  }
577 
578  // parse the second object (we want a mixed array)
579  if (amf_parse_object(s, astream, vstream, buffer, next_pos, 0) < 0)
580  return -1;
581 
582  return 0;
583 }
584 
586 {
587  int offset, flags;
588 
589  avio_skip(s->pb, 4);
590  flags = avio_r8(s->pb);
591 
593 
594  if (flags & FLV_HEADER_FLAG_HASVIDEO)
596  return AVERROR(ENOMEM);
597  if (flags & FLV_HEADER_FLAG_HASAUDIO)
599  return AVERROR(ENOMEM);
600  // Flag doesn't indicate whether or not there is script-data present. Must
601  // create that stream if it's encountered.
602 
603  offset = avio_rb32(s->pb);
604  avio_seek(s->pb, offset, SEEK_SET);
605  avio_skip(s->pb, 4);
606 
607  s->start_time = 0;
608 
609  return 0;
610 }
611 
613 {
614  int i;
615  FLVContext *flv = s->priv_data;
616  for (i=0; i<FLV_STREAM_TYPE_NB; i++)
617  av_freep(&flv->new_extradata[i]);
618  return 0;
619 }
620 
622 {
623  av_free(st->codec->extradata);
624  if (ff_get_extradata(st->codec, s->pb, size) < 0)
625  return AVERROR(ENOMEM);
626  return 0;
627 }
628 
629 static int flv_queue_extradata(FLVContext *flv, AVIOContext *pb, int stream,
630  int size)
631 {
632  av_free(flv->new_extradata[stream]);
633  flv->new_extradata[stream] = av_mallocz(size +
635  if (!flv->new_extradata[stream])
636  return AVERROR(ENOMEM);
637  flv->new_extradata_size[stream] = size;
638  avio_read(pb, flv->new_extradata[stream], size);
639  return 0;
640 }
641 
642 static void clear_index_entries(AVFormatContext *s, int64_t pos)
643 {
644  int i, j, out;
646  "Found invalid index entries, clearing the index.\n");
647  for (i = 0; i < s->nb_streams; i++) {
648  AVStream *st = s->streams[i];
649  /* Remove all index entries that point to >= pos */
650  out = 0;
651  for (j = 0; j < st->nb_index_entries; j++)
652  if (st->index_entries[j].pos < pos)
653  st->index_entries[out++] = st->index_entries[j];
654  st->nb_index_entries = out;
655  }
656 }
657 
659 {
660  int nb = -1, ret, parse_name = 1;
661 
662  switch (type) {
664  avio_skip(pb, 8);
665  break;
666  case AMF_DATA_TYPE_BOOL:
667  avio_skip(pb, 1);
668  break;
670  avio_skip(pb, avio_rb16(pb));
671  break;
672  case AMF_DATA_TYPE_ARRAY:
673  parse_name = 0;
675  nb = avio_rb32(pb);
677  while(!pb->eof_reached && (nb-- > 0 || type != AMF_DATA_TYPE_ARRAY)) {
678  if (parse_name) {
679  int size = avio_rb16(pb);
680  if (!size) {
681  avio_skip(pb, 1);
682  break;
683  }
684  avio_skip(pb, size);
685  }
686  if ((ret = amf_skip_tag(pb, avio_r8(pb))) < 0)
687  return ret;
688  }
689  break;
690  case AMF_DATA_TYPE_NULL:
692  break;
693  default:
694  return AVERROR_INVALIDDATA;
695  }
696  return 0;
697 }
698 
700  int64_t dts, int64_t next)
701 {
702  AVIOContext *pb = s->pb;
703  AVStream *st = NULL;
704  char buf[20];
705  int ret = AVERROR_INVALIDDATA;
706  int i, length = -1;
707 
708  switch (avio_r8(pb)) {
710  avio_seek(pb, 4, SEEK_CUR);
712  break;
713  default:
714  goto skip;
715  }
716 
717  while ((ret = amf_get_string(pb, buf, sizeof(buf))) > 0) {
718  AMFDataType type = avio_r8(pb);
719  if (type == AMF_DATA_TYPE_STRING && !strcmp(buf, "text")) {
720  length = avio_rb16(pb);
721  ret = av_get_packet(pb, pkt, length);
722  if (ret < 0)
723  goto skip;
724  else
725  break;
726  } else {
727  if ((ret = amf_skip_tag(pb, type)) < 0)
728  goto skip;
729  }
730  }
731 
732  if (length < 0) {
733  ret = AVERROR_INVALIDDATA;
734  goto skip;
735  }
736 
737  for (i = 0; i < s->nb_streams; i++) {
738  st = s->streams[i];
739  if (st->codec->codec_type == AVMEDIA_TYPE_DATA)
740  break;
741  }
742 
743  if (i == s->nb_streams) {
745  if (!st)
746  return AVERROR_INVALIDDATA;
748  }
749 
750  pkt->dts = dts;
751  pkt->pts = dts;
752  pkt->size = ret;
753 
754  pkt->stream_index = st->index;
755  pkt->flags |= AV_PKT_FLAG_KEY;
756 
757 skip:
758  avio_seek(s->pb, next + 4, SEEK_SET);
759 
760  return ret;
761 }
762 
764 {
765  FLVContext *flv = s->priv_data;
766  int ret, i, type, size, flags;
767  int stream_type=-1;
768  int64_t next, pos, meta_pos;
769  int64_t dts, pts = AV_NOPTS_VALUE;
770  int av_uninit(channels);
771  int av_uninit(sample_rate);
772  AVStream *st = NULL;
773 
774  /* pkt size is repeated at end. skip it */
775  for (;; avio_skip(s->pb, 4)) {
776  pos = avio_tell(s->pb);
777  type = avio_r8(s->pb);
778  size = avio_rb24(s->pb);
779  dts = avio_rb24(s->pb);
780  dts |= avio_r8(s->pb) << 24;
781  av_dlog(s, "type:%d, size:%d, dts:%"PRId64" pos:%"PRId64"\n", type, size, dts, avio_tell(s->pb));
782  if (url_feof(s->pb))
783  return AVERROR_EOF;
784  avio_skip(s->pb, 3); /* stream id, always 0 */
785  flags = 0;
786 
787  if (flv->validate_next < flv->validate_count) {
788  int64_t validate_pos = flv->validate_index[flv->validate_next].pos;
789  if (pos == validate_pos) {
790  if (FFABS(dts - flv->validate_index[flv->validate_next].dts) <=
792  flv->validate_next++;
793  } else {
794  clear_index_entries(s, validate_pos);
795  flv->validate_count = 0;
796  }
797  } else if (pos > validate_pos) {
798  clear_index_entries(s, validate_pos);
799  flv->validate_count = 0;
800  }
801  }
802 
803  if (size == 0)
804  continue;
805 
806  next = size + avio_tell(s->pb);
807 
808  if (type == FLV_TAG_TYPE_AUDIO) {
809  stream_type = FLV_STREAM_TYPE_AUDIO;
810  flags = avio_r8(s->pb);
811  size--;
812  } else if (type == FLV_TAG_TYPE_VIDEO) {
813  stream_type = FLV_STREAM_TYPE_VIDEO;
814  flags = avio_r8(s->pb);
815  size--;
817  goto skip;
818  } else if (type == FLV_TAG_TYPE_META) {
819  stream_type=FLV_STREAM_TYPE_DATA;
820  if (size > 13 + 1 + 4 && dts == 0) { // Header-type metadata stuff
821  meta_pos = avio_tell(s->pb);
822  if (flv_read_metabody(s, next) == 0) {
823  goto skip;
824  }
825  avio_seek(s->pb, meta_pos, SEEK_SET);
826  }
827  } else {
828  av_log(s, AV_LOG_DEBUG,
829  "Skipping flv packet: type %d, size %d, flags %d.\n",
830  type, size, flags);
831 skip:
832  avio_seek(s->pb, next, SEEK_SET);
833  continue;
834  }
835 
836  /* skip empty data packets */
837  if (!size)
838  continue;
839 
840  /* now find stream */
841  for (i = 0; i < s->nb_streams; i++) {
842  st = s->streams[i];
843  if (stream_type == FLV_STREAM_TYPE_AUDIO) {
844  if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO &&
845  (s->audio_codec_id || flv_same_audio_codec(st->codec, flags)))
846  break;
847  } else if (stream_type == FLV_STREAM_TYPE_VIDEO) {
848  if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO &&
849  (s->video_codec_id || flv_same_video_codec(st->codec, flags)))
850  break;
851  } else if (stream_type == FLV_STREAM_TYPE_DATA) {
852  if (st->codec->codec_type == AVMEDIA_TYPE_DATA)
853  break;
854  }
855  }
856  if (i == s->nb_streams) {
857  static const enum AVMediaType stream_types[] = {AVMEDIA_TYPE_VIDEO, AVMEDIA_TYPE_AUDIO, AVMEDIA_TYPE_DATA};
858  av_log(s, AV_LOG_WARNING, "Stream discovered after head already parsed\n");
859  st = create_stream(s, stream_types[stream_type]);
860  if (!st)
861  return AVERROR(ENOMEM);
862 
863  }
864  av_dlog(s, "%d %X %d \n", stream_type, flags, st->discard);
865  if ( (st->discard >= AVDISCARD_NONKEY && !((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_KEY || (stream_type == FLV_STREAM_TYPE_AUDIO)))
866  ||(st->discard >= AVDISCARD_BIDIR && ((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_DISP_INTER && (stream_type == FLV_STREAM_TYPE_VIDEO)))
867  || st->discard >= AVDISCARD_ALL
868  ) {
869  avio_seek(s->pb, next, SEEK_SET);
870  continue;
871  }
872  if ((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_KEY || stream_type == FLV_STREAM_TYPE_AUDIO)
873  av_add_index_entry(st, pos, dts, size, 0, AVINDEX_KEYFRAME);
874  break;
875  }
876 
877  // if not streamed and no duration from metadata then seek to end to find
878  // the duration from the timestamps
879  if (s->pb->seekable && (!s->duration || s->duration == AV_NOPTS_VALUE) && !flv->searched_for_end) {
880  int size;
881  const int64_t pos = avio_tell(s->pb);
882  int64_t fsize = avio_size(s->pb);
883 retry_duration:
884  avio_seek(s->pb, fsize - 4, SEEK_SET);
885  size = avio_rb32(s->pb);
886  avio_seek(s->pb, fsize - 3 - size, SEEK_SET);
887  if (size == avio_rb24(s->pb) + 11) {
888  uint32_t ts = avio_rb24(s->pb);
889  ts |= avio_r8(s->pb) << 24;
890  if (ts)
891  s->duration = ts * (int64_t)AV_TIME_BASE / 1000;
892  else if (fsize >= 8 && fsize - 8 >= size) {
893  fsize -= size+4;
894  goto retry_duration;
895  }
896  }
897 
898  avio_seek(s->pb, pos, SEEK_SET);
899  flv->searched_for_end = 1;
900  }
901 
902  if (stream_type == FLV_STREAM_TYPE_AUDIO) {
903  int bits_per_coded_sample;
904  channels = (flags & FLV_AUDIO_CHANNEL_MASK) == FLV_STEREO ? 2 : 1;
905  sample_rate = 44100 << ((flags & FLV_AUDIO_SAMPLERATE_MASK) >>
907  bits_per_coded_sample = (flags & FLV_AUDIO_SAMPLESIZE_MASK) ? 16 : 8;
908  if (!st->codec->channels || !st->codec->sample_rate ||
910  st->codec->channels = channels;
911  st->codec->channel_layout = channels == 1
915  st->codec->bits_per_coded_sample = bits_per_coded_sample;
916  }
917  if (!st->codec->codec_id) {
918  flv_set_audio_codec(s, st, st->codec,
919  flags & FLV_AUDIO_CODECID_MASK);
920  flv->last_sample_rate =
922  flv->last_channels =
923  channels = st->codec->channels;
924  } else {
925  AVCodecContext ctx = {0};
926  ctx.sample_rate = sample_rate;
927  flv_set_audio_codec(s, st, &ctx, flags & FLV_AUDIO_CODECID_MASK);
928  sample_rate = ctx.sample_rate;
929  }
930  } else if (stream_type == FLV_STREAM_TYPE_VIDEO) {
931  size -= flv_set_video_codec(s, st, flags & FLV_VIDEO_CODECID_MASK, 1);
932  }
933 
934  if (st->codec->codec_id == AV_CODEC_ID_AAC ||
935  st->codec->codec_id == AV_CODEC_ID_H264 ||
936  st->codec->codec_id == AV_CODEC_ID_MPEG4) {
937  int type = avio_r8(s->pb);
938  size--;
940  // sign extension
941  int32_t cts = (avio_rb24(s->pb) + 0xff800000) ^ 0xff800000;
942  pts = dts + cts;
943  if (cts < 0) { // dts might be wrong
944  if (!flv->wrong_dts)
946  "Negative cts, previous timestamps might be wrong.\n");
947  flv->wrong_dts = 1;
948  } else if (FFABS(dts - pts) > 1000*60*15) {
950  "invalid timestamps %"PRId64" %"PRId64"\n", dts, pts);
951  dts = pts = AV_NOPTS_VALUE;
952  }
953  }
954  if (type == 0 && (!st->codec->extradata || st->codec->codec_id == AV_CODEC_ID_AAC ||
955  st->codec->codec_id == AV_CODEC_ID_H264)) {
957 
958  if (st->codec->extradata) {
959  if ((ret = flv_queue_extradata(flv, s->pb, stream_type, size)) < 0)
960  return ret;
961  ret = AVERROR(EAGAIN);
962  goto leave;
963  }
964  if ((ret = flv_get_extradata(s, st, size)) < 0)
965  return ret;
966 
967  /* Workaround for buggy Omnia A/XE encoder */
968  t = av_dict_get(s->metadata, "Encoder", NULL, 0);
969  if (st->codec->codec_id == AV_CODEC_ID_AAC && t && !strcmp(t->value, "Omnia A/XE"))
970  st->codec->extradata_size = 2;
971 
972  if (st->codec->codec_id == AV_CODEC_ID_AAC && 0) {
973  MPEG4AudioConfig cfg;
974 
976  st->codec->extradata_size * 8, 1) >= 0) {
977  st->codec->channels = cfg.channels;
978  st->codec->channel_layout = 0;
979  if (cfg.ext_sample_rate)
980  st->codec->sample_rate = cfg.ext_sample_rate;
981  else
982  st->codec->sample_rate = cfg.sample_rate;
983  av_dlog(s, "mp4a config channels %d sample rate %d\n",
984  st->codec->channels, st->codec->sample_rate);
985  }
986  }
987 
988  ret = AVERROR(EAGAIN);
989  goto leave;
990  }
991  }
992 
993  /* skip empty data packets */
994  if (!size) {
995  ret = AVERROR(EAGAIN);
996  goto leave;
997  }
998 
999  ret = av_get_packet(s->pb, pkt, size);
1000  if (ret < 0)
1001  return ret;
1002  pkt->dts = dts;
1003  pkt->pts = pts == AV_NOPTS_VALUE ? dts : pts;
1004  pkt->stream_index = st->index;
1005  if (flv->new_extradata[stream_type]) {
1007  flv->new_extradata_size[stream_type]);
1008  if (side) {
1009  memcpy(side, flv->new_extradata[stream_type],
1010  flv->new_extradata_size[stream_type]);
1011  av_freep(&flv->new_extradata[stream_type]);
1012  flv->new_extradata_size[stream_type] = 0;
1013  }
1014  }
1015  if (stream_type == FLV_STREAM_TYPE_AUDIO &&
1016  (sample_rate != flv->last_sample_rate ||
1017  channels != flv->last_channels)) {
1019  flv->last_channels = channels;
1020  ff_add_param_change(pkt, channels, 0, sample_rate, 0, 0);
1021  }
1022 
1023  if ( stream_type == FLV_STREAM_TYPE_AUDIO ||
1024  ((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_KEY) ||
1025  stream_type == FLV_STREAM_TYPE_DATA)
1026  pkt->flags |= AV_PKT_FLAG_KEY;
1027 
1028 leave:
1029  avio_skip(s->pb, 4);
1030  return ret;
1031 }
1032 
1033 static int flv_read_seek(AVFormatContext *s, int stream_index,
1034  int64_t ts, int flags)
1035 {
1036  FLVContext *flv = s->priv_data;
1037  flv->validate_count = 0;
1038  return avio_seek_time(s->pb, stream_index, ts, flags);
1039 }
1040 
1041 #define OFFSET(x) offsetof(FLVContext, x)
1042 #define VD AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_DECODING_PARAM
1043 static const AVOption options[] = {
1044  { "flv_metadata", "Allocate streams according to the onMetaData array", OFFSET(trust_metadata), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, VD },
1045  { NULL }
1046 };
1047 
1048 static const AVClass flv_class = {
1049  .class_name = "flvdec",
1050  .item_name = av_default_item_name,
1051  .option = options,
1052  .version = LIBAVUTIL_VERSION_INT,
1053 };
1054 
1056  .name = "flv",
1057  .long_name = NULL_IF_CONFIG_SMALL("FLV (Flash Video)"),
1058  .priv_data_size = sizeof(FLVContext),
1059  .read_probe = flv_probe,
1064  .extensions = "flv",
1065  .priv_class = &flv_class,
1066 };
1067 
1068 static const AVClass live_flv_class = {
1069  .class_name = "live_flvdec",
1070  .item_name = av_default_item_name,
1071  .option = options,
1072  .version = LIBAVUTIL_VERSION_INT,
1073 };
1074 
1076  .name = "live_flv",
1077  .long_name = NULL_IF_CONFIG_SMALL("live RTMP FLV (Flash Video)"),
1078  .priv_data_size = sizeof(FLVContext),
1084  .extensions = "flv",
1085  .priv_class = &live_flv_class,
1087 };