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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[1024];
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  av_log(s, AV_LOG_ERROR, "AMF_DATA_TYPE_STRING parsing failed\n");
410  return -1;
411  }
412  break;
414  if ((vstream || astream) && key &&
415  ioc->seekable &&
416  !strcmp(KEYFRAMES_TAG, key) && depth == 1)
417  if (parse_keyframes_index(s, ioc, vstream ? vstream : astream,
418  max_pos) < 0)
419  av_log(s, AV_LOG_ERROR, "Keyframe index parsing failed\n");
420 
421  while (avio_tell(ioc) < max_pos - 2 &&
422  amf_get_string(ioc, str_val, sizeof(str_val)) > 0)
423  if (amf_parse_object(s, astream, vstream, str_val, max_pos,
424  depth + 1) < 0)
425  return -1; // if we couldn't skip, bomb out.
426  if (avio_r8(ioc) != AMF_END_OF_OBJECT) {
427  av_log(s, AV_LOG_ERROR, "Missing AMF_END_OF_OBJECT in AMF_DATA_TYPE_OBJECT\n");
428  return -1;
429  }
430  break;
431  case AMF_DATA_TYPE_NULL:
434  break; // these take up no additional space
436  avio_skip(ioc, 4); // skip 32-bit max array index
437  while (avio_tell(ioc) < max_pos - 2 &&
438  amf_get_string(ioc, str_val, sizeof(str_val)) > 0)
439  // this is the only case in which we would want a nested
440  // parse to not skip over the object
441  if (amf_parse_object(s, astream, vstream, str_val, max_pos,
442  depth + 1) < 0)
443  return -1;
444  if (avio_r8(ioc) != AMF_END_OF_OBJECT) {
445  av_log(s, AV_LOG_ERROR, "Missing AMF_END_OF_OBJECT in AMF_DATA_TYPE_MIXEDARRAY\n");
446  return -1;
447  }
448  break;
449  case AMF_DATA_TYPE_ARRAY:
450  {
451  unsigned int arraylen, i;
452 
453  arraylen = avio_rb32(ioc);
454  for (i = 0; i < arraylen && avio_tell(ioc) < max_pos - 1; i++)
455  if (amf_parse_object(s, NULL, NULL, NULL, max_pos,
456  depth + 1) < 0)
457  return -1; // if we couldn't skip, bomb out.
458  }
459  break;
460  case AMF_DATA_TYPE_DATE:
461  avio_skip(ioc, 8 + 2); // timestamp (double) and UTC offset (int16)
462  break;
463  default: // unsupported type, we couldn't skip
464  av_log(s, AV_LOG_ERROR, "unsupported amf type %d\n", amf_type);
465  return -1;
466  }
467 
468  if (key) {
469  acodec = astream ? astream->codec : NULL;
470  vcodec = vstream ? vstream->codec : NULL;
471 
472  // stream info doesn't live any deeper than the first object
473  if (depth == 1) {
474  if (amf_type == AMF_DATA_TYPE_NUMBER ||
475  amf_type == AMF_DATA_TYPE_BOOL) {
476  if (!strcmp(key, "duration"))
477  s->duration = num_val * AV_TIME_BASE;
478  else if (!strcmp(key, "videodatarate") && vcodec &&
479  0 <= (int)(num_val * 1024.0))
480  vcodec->bit_rate = num_val * 1024.0;
481  else if (!strcmp(key, "audiodatarate") && acodec &&
482  0 <= (int)(num_val * 1024.0))
483  acodec->bit_rate = num_val * 1024.0;
484  else if (!strcmp(key, "datastream")) {
486  if (!st)
487  return AVERROR(ENOMEM);
489  } else if (flv->trust_metadata) {
490  if (!strcmp(key, "videocodecid") && vcodec) {
491  flv_set_video_codec(s, vstream, num_val, 0);
492  } else if (!strcmp(key, "audiocodecid") && acodec) {
493  int id = ((int)num_val) << FLV_AUDIO_CODECID_OFFSET;
494  flv_set_audio_codec(s, astream, acodec, id);
495  } else if (!strcmp(key, "audiosamplerate") && acodec) {
496  acodec->sample_rate = num_val;
497  } else if (!strcmp(key, "audiosamplesize") && acodec) {
498  acodec->bits_per_coded_sample = num_val;
499  } else if (!strcmp(key, "stereo") && acodec) {
500  acodec->channels = num_val + 1;
501  acodec->channel_layout = acodec->channels == 2 ?
504  } else if (!strcmp(key, "width") && vcodec) {
505  vcodec->width = num_val;
506  } else if (!strcmp(key, "height") && vcodec) {
507  vcodec->height = num_val;
508  }
509  }
510  }
511  }
512 
513  if (amf_type == AMF_DATA_TYPE_OBJECT && s->nb_streams == 1 &&
514  ((!acodec && !strcmp(key, "audiocodecid")) ||
515  (!vcodec && !strcmp(key, "videocodecid"))))
516  s->ctx_flags &= ~AVFMTCTX_NOHEADER; //If there is either audio/video missing, codecid will be an empty object
517 
518  if (!strcmp(key, "duration") ||
519  !strcmp(key, "filesize") ||
520  !strcmp(key, "width") ||
521  !strcmp(key, "height") ||
522  !strcmp(key, "videodatarate") ||
523  !strcmp(key, "framerate") ||
524  !strcmp(key, "videocodecid") ||
525  !strcmp(key, "audiodatarate") ||
526  !strcmp(key, "audiosamplerate") ||
527  !strcmp(key, "audiosamplesize") ||
528  !strcmp(key, "stereo") ||
529  !strcmp(key, "audiocodecid") ||
530  !strcmp(key, "datastream"))
531  return 0;
532 
534  if (amf_type == AMF_DATA_TYPE_BOOL) {
535  av_strlcpy(str_val, num_val > 0 ? "true" : "false",
536  sizeof(str_val));
537  av_dict_set(&s->metadata, key, str_val, 0);
538  } else if (amf_type == AMF_DATA_TYPE_NUMBER) {
539  snprintf(str_val, sizeof(str_val), "%.f", num_val);
540  av_dict_set(&s->metadata, key, str_val, 0);
541  } else if (amf_type == AMF_DATA_TYPE_STRING)
542  av_dict_set(&s->metadata, key, str_val, 0);
543  }
544 
545  return 0;
546 }
547 
548 #define TYPE_ONTEXTDATA 1
549 #define TYPE_UNKNOWN 2
550 
551 static int flv_read_metabody(AVFormatContext *s, int64_t next_pos)
552 {
554  AVStream *stream, *astream, *vstream;
555  AVStream av_unused *dstream;
556  AVIOContext *ioc;
557  int i;
558  // only needs to hold the string "onMetaData".
559  // Anything longer is something we don't want.
560  char buffer[11];
561 
562  astream = NULL;
563  vstream = NULL;
564  dstream = NULL;
565  ioc = s->pb;
566 
567  // first object needs to be "onMetaData" string
568  type = avio_r8(ioc);
569  if (type != AMF_DATA_TYPE_STRING ||
570  amf_get_string(ioc, buffer, sizeof(buffer)) < 0)
571  return TYPE_UNKNOWN;
572 
573  if (!strcmp(buffer, "onTextData"))
574  return TYPE_ONTEXTDATA;
575 
576  if (strcmp(buffer, "onMetaData") && strcmp(buffer, "onCuePoint"))
577  return TYPE_UNKNOWN;
578 
579  // find the streams now so that amf_parse_object doesn't need to do
580  // the lookup every time it is called.
581  for (i = 0; i < s->nb_streams; i++) {
582  stream = s->streams[i];
583  if (stream->codec->codec_type == AVMEDIA_TYPE_VIDEO)
584  vstream = stream;
585  else if (stream->codec->codec_type == AVMEDIA_TYPE_AUDIO)
586  astream = stream;
587  else if (stream->codec->codec_type == AVMEDIA_TYPE_DATA)
588  dstream = stream;
589  }
590 
591  // parse the second object (we want a mixed array)
592  if (amf_parse_object(s, astream, vstream, buffer, next_pos, 0) < 0)
593  return -1;
594 
595  return 0;
596 }
597 
599 {
600  int offset, flags;
601 
602  avio_skip(s->pb, 4);
603  flags = avio_r8(s->pb);
604 
606 
607  if (flags & FLV_HEADER_FLAG_HASVIDEO)
609  return AVERROR(ENOMEM);
610  if (flags & FLV_HEADER_FLAG_HASAUDIO)
612  return AVERROR(ENOMEM);
613  // Flag doesn't indicate whether or not there is script-data present. Must
614  // create that stream if it's encountered.
615 
616  offset = avio_rb32(s->pb);
617  avio_seek(s->pb, offset, SEEK_SET);
618  avio_skip(s->pb, 4);
619 
620  s->start_time = 0;
621 
622  return 0;
623 }
624 
626 {
627  int i;
628  FLVContext *flv = s->priv_data;
629  for (i=0; i<FLV_STREAM_TYPE_NB; i++)
630  av_freep(&flv->new_extradata[i]);
631  return 0;
632 }
633 
635 {
636  av_freep(&st->codec->extradata);
637  if (ff_get_extradata(st->codec, s->pb, size) < 0)
638  return AVERROR(ENOMEM);
639  return 0;
640 }
641 
642 static int flv_queue_extradata(FLVContext *flv, AVIOContext *pb, int stream,
643  int size)
644 {
645  av_free(flv->new_extradata[stream]);
646  flv->new_extradata[stream] = av_mallocz(size +
648  if (!flv->new_extradata[stream])
649  return AVERROR(ENOMEM);
650  flv->new_extradata_size[stream] = size;
651  avio_read(pb, flv->new_extradata[stream], size);
652  return 0;
653 }
654 
655 static void clear_index_entries(AVFormatContext *s, int64_t pos)
656 {
657  int i, j, out;
659  "Found invalid index entries, clearing the index.\n");
660  for (i = 0; i < s->nb_streams; i++) {
661  AVStream *st = s->streams[i];
662  /* Remove all index entries that point to >= pos */
663  out = 0;
664  for (j = 0; j < st->nb_index_entries; j++)
665  if (st->index_entries[j].pos < pos)
666  st->index_entries[out++] = st->index_entries[j];
667  st->nb_index_entries = out;
668  }
669 }
670 
672 {
673  int nb = -1, ret, parse_name = 1;
674 
675  switch (type) {
677  avio_skip(pb, 8);
678  break;
679  case AMF_DATA_TYPE_BOOL:
680  avio_skip(pb, 1);
681  break;
683  avio_skip(pb, avio_rb16(pb));
684  break;
685  case AMF_DATA_TYPE_ARRAY:
686  parse_name = 0;
688  nb = avio_rb32(pb);
690  while(!pb->eof_reached && (nb-- > 0 || type != AMF_DATA_TYPE_ARRAY)) {
691  if (parse_name) {
692  int size = avio_rb16(pb);
693  if (!size) {
694  avio_skip(pb, 1);
695  break;
696  }
697  avio_skip(pb, size);
698  }
699  if ((ret = amf_skip_tag(pb, avio_r8(pb))) < 0)
700  return ret;
701  }
702  break;
703  case AMF_DATA_TYPE_NULL:
705  break;
706  default:
707  return AVERROR_INVALIDDATA;
708  }
709  return 0;
710 }
711 
713  int64_t dts, int64_t next)
714 {
715  AVIOContext *pb = s->pb;
716  AVStream *st = NULL;
717  char buf[20];
718  int ret = AVERROR_INVALIDDATA;
719  int i, length = -1;
720 
721  switch (avio_r8(pb)) {
723  avio_seek(pb, 4, SEEK_CUR);
725  break;
726  default:
727  goto skip;
728  }
729 
730  while ((ret = amf_get_string(pb, buf, sizeof(buf))) > 0) {
731  AMFDataType type = avio_r8(pb);
732  if (type == AMF_DATA_TYPE_STRING && !strcmp(buf, "text")) {
733  length = avio_rb16(pb);
734  ret = av_get_packet(pb, pkt, length);
735  if (ret < 0)
736  goto skip;
737  else
738  break;
739  } else {
740  if ((ret = amf_skip_tag(pb, type)) < 0)
741  goto skip;
742  }
743  }
744 
745  if (length < 0) {
746  ret = AVERROR_INVALIDDATA;
747  goto skip;
748  }
749 
750  for (i = 0; i < s->nb_streams; i++) {
751  st = s->streams[i];
752  if (st->codec->codec_type == AVMEDIA_TYPE_DATA)
753  break;
754  }
755 
756  if (i == s->nb_streams) {
758  if (!st)
759  return AVERROR(ENOMEM);
761  }
762 
763  pkt->dts = dts;
764  pkt->pts = dts;
765  pkt->size = ret;
766 
767  pkt->stream_index = st->index;
768  pkt->flags |= AV_PKT_FLAG_KEY;
769 
770 skip:
771  avio_seek(s->pb, next + 4, SEEK_SET);
772 
773  return ret;
774 }
775 
777 {
778  FLVContext *flv = s->priv_data;
779  int ret, i, type, size, flags;
780  int stream_type=-1;
781  int64_t next, pos, meta_pos;
782  int64_t dts, pts = AV_NOPTS_VALUE;
783  int av_uninit(channels);
784  int av_uninit(sample_rate);
785  AVStream *st = NULL;
786 
787  /* pkt size is repeated at end. skip it */
788  for (;; avio_skip(s->pb, 4)) {
789  pos = avio_tell(s->pb);
790  type = (avio_r8(s->pb) & 0x1F);
791  size = avio_rb24(s->pb);
792  dts = avio_rb24(s->pb);
793  dts |= avio_r8(s->pb) << 24;
794  av_dlog(s, "type:%d, size:%d, dts:%"PRId64" pos:%"PRId64"\n", type, size, dts, avio_tell(s->pb));
795  if (avio_feof(s->pb))
796  return AVERROR_EOF;
797  avio_skip(s->pb, 3); /* stream id, always 0 */
798  flags = 0;
799 
800  if (flv->validate_next < flv->validate_count) {
801  int64_t validate_pos = flv->validate_index[flv->validate_next].pos;
802  if (pos == validate_pos) {
803  if (FFABS(dts - flv->validate_index[flv->validate_next].dts) <=
805  flv->validate_next++;
806  } else {
807  clear_index_entries(s, validate_pos);
808  flv->validate_count = 0;
809  }
810  } else if (pos > validate_pos) {
811  clear_index_entries(s, validate_pos);
812  flv->validate_count = 0;
813  }
814  }
815 
816  if (size == 0)
817  continue;
818 
819  next = size + avio_tell(s->pb);
820 
821  if (type == FLV_TAG_TYPE_AUDIO) {
822  stream_type = FLV_STREAM_TYPE_AUDIO;
823  flags = avio_r8(s->pb);
824  size--;
825  } else if (type == FLV_TAG_TYPE_VIDEO) {
826  stream_type = FLV_STREAM_TYPE_VIDEO;
827  flags = avio_r8(s->pb);
828  size--;
830  goto skip;
831  } else if (type == FLV_TAG_TYPE_META) {
832  stream_type=FLV_STREAM_TYPE_DATA;
833  if (size > 13 + 1 + 4 && dts == 0) { // Header-type metadata stuff
834  meta_pos = avio_tell(s->pb);
835  if (flv_read_metabody(s, next) <= 0) {
836  goto skip;
837  }
838  avio_seek(s->pb, meta_pos, SEEK_SET);
839  }
840  } else {
841  av_log(s, AV_LOG_DEBUG,
842  "Skipping flv packet: type %d, size %d, flags %d.\n",
843  type, size, flags);
844 skip:
845  avio_seek(s->pb, next, SEEK_SET);
846  continue;
847  }
848 
849  /* skip empty data packets */
850  if (!size)
851  continue;
852 
853  /* now find stream */
854  for (i = 0; i < s->nb_streams; i++) {
855  st = s->streams[i];
856  if (stream_type == FLV_STREAM_TYPE_AUDIO) {
857  if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO &&
858  (s->audio_codec_id || flv_same_audio_codec(st->codec, flags)))
859  break;
860  } else if (stream_type == FLV_STREAM_TYPE_VIDEO) {
861  if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO &&
862  (s->video_codec_id || flv_same_video_codec(st->codec, flags)))
863  break;
864  } else if (stream_type == FLV_STREAM_TYPE_DATA) {
865  if (st->codec->codec_type == AVMEDIA_TYPE_DATA)
866  break;
867  }
868  }
869  if (i == s->nb_streams) {
870  static const enum AVMediaType stream_types[] = {AVMEDIA_TYPE_VIDEO, AVMEDIA_TYPE_AUDIO, AVMEDIA_TYPE_DATA};
871  av_log(s, AV_LOG_WARNING, "Stream discovered after head already parsed\n");
872  st = create_stream(s, stream_types[stream_type]);
873  if (!st)
874  return AVERROR(ENOMEM);
875 
876  }
877  av_dlog(s, "%d %X %d \n", stream_type, flags, st->discard);
878 
879  if ((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_KEY ||
880  stream_type == FLV_STREAM_TYPE_AUDIO)
881  av_add_index_entry(st, pos, dts, size, 0, AVINDEX_KEYFRAME);
882 
883  if ( (st->discard >= AVDISCARD_NONKEY && !((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_KEY || (stream_type == FLV_STREAM_TYPE_AUDIO)))
884  ||(st->discard >= AVDISCARD_BIDIR && ((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_DISP_INTER && (stream_type == FLV_STREAM_TYPE_VIDEO)))
885  || st->discard >= AVDISCARD_ALL
886  ) {
887  avio_seek(s->pb, next, SEEK_SET);
888  continue;
889  }
890  break;
891  }
892 
893  // if not streamed and no duration from metadata then seek to end to find
894  // the duration from the timestamps
895  if (s->pb->seekable && (!s->duration || s->duration == AV_NOPTS_VALUE) && !flv->searched_for_end) {
896  int size;
897  const int64_t pos = avio_tell(s->pb);
898  // Read the last 4 bytes of the file, this should be the size of the
899  // previous FLV tag. Use the timestamp of its payload as duration.
900  int64_t fsize = avio_size(s->pb);
901 retry_duration:
902  avio_seek(s->pb, fsize - 4, SEEK_SET);
903  size = avio_rb32(s->pb);
904  // Seek to the start of the last FLV tag at position (fsize - 4 - size)
905  // but skip the byte indicating the type.
906  avio_seek(s->pb, fsize - 3 - size, SEEK_SET);
907  if (size == avio_rb24(s->pb) + 11) {
908  uint32_t ts = avio_rb24(s->pb);
909  ts |= avio_r8(s->pb) << 24;
910  if (ts)
911  s->duration = ts * (int64_t)AV_TIME_BASE / 1000;
912  else if (fsize >= 8 && fsize - 8 >= size) {
913  fsize -= size+4;
914  goto retry_duration;
915  }
916  }
917 
918  avio_seek(s->pb, pos, SEEK_SET);
919  flv->searched_for_end = 1;
920  }
921 
922  if (stream_type == FLV_STREAM_TYPE_AUDIO) {
923  int bits_per_coded_sample;
924  channels = (flags & FLV_AUDIO_CHANNEL_MASK) == FLV_STEREO ? 2 : 1;
925  sample_rate = 44100 << ((flags & FLV_AUDIO_SAMPLERATE_MASK) >>
927  bits_per_coded_sample = (flags & FLV_AUDIO_SAMPLESIZE_MASK) ? 16 : 8;
928  if (!st->codec->channels || !st->codec->sample_rate ||
930  st->codec->channels = channels;
931  st->codec->channel_layout = channels == 1
935  st->codec->bits_per_coded_sample = bits_per_coded_sample;
936  }
937  if (!st->codec->codec_id) {
938  flv_set_audio_codec(s, st, st->codec,
939  flags & FLV_AUDIO_CODECID_MASK);
940  flv->last_sample_rate =
942  flv->last_channels =
943  channels = st->codec->channels;
944  } else {
945  AVCodecContext ctx = {0};
946  ctx.sample_rate = sample_rate;
947  ctx.bits_per_coded_sample = bits_per_coded_sample;
948  flv_set_audio_codec(s, st, &ctx, flags & FLV_AUDIO_CODECID_MASK);
949  sample_rate = ctx.sample_rate;
950  }
951  } else if (stream_type == FLV_STREAM_TYPE_VIDEO) {
952  size -= flv_set_video_codec(s, st, flags & FLV_VIDEO_CODECID_MASK, 1);
953  }
954 
955  if (st->codec->codec_id == AV_CODEC_ID_AAC ||
956  st->codec->codec_id == AV_CODEC_ID_H264 ||
957  st->codec->codec_id == AV_CODEC_ID_MPEG4) {
958  int type = avio_r8(s->pb);
959  size--;
961  // sign extension
962  int32_t cts = (avio_rb24(s->pb) + 0xff800000) ^ 0xff800000;
963  pts = dts + cts;
964  if (cts < 0) { // dts might be wrong
965  if (!flv->wrong_dts)
967  "Negative cts, previous timestamps might be wrong.\n");
968  flv->wrong_dts = 1;
969  } else if (FFABS(dts - pts) > 1000*60*15) {
971  "invalid timestamps %"PRId64" %"PRId64"\n", dts, pts);
972  dts = pts = AV_NOPTS_VALUE;
973  }
974  }
975  if (type == 0 && (!st->codec->extradata || st->codec->codec_id == AV_CODEC_ID_AAC ||
976  st->codec->codec_id == AV_CODEC_ID_H264)) {
978 
979  if (st->codec->extradata) {
980  if ((ret = flv_queue_extradata(flv, s->pb, stream_type, size)) < 0)
981  return ret;
982  ret = AVERROR(EAGAIN);
983  goto leave;
984  }
985  if ((ret = flv_get_extradata(s, st, size)) < 0)
986  return ret;
987 
988  /* Workaround for buggy Omnia A/XE encoder */
989  t = av_dict_get(s->metadata, "Encoder", NULL, 0);
990  if (st->codec->codec_id == AV_CODEC_ID_AAC && t && !strcmp(t->value, "Omnia A/XE"))
991  st->codec->extradata_size = 2;
992 
993  if (st->codec->codec_id == AV_CODEC_ID_AAC && 0) {
994  MPEG4AudioConfig cfg;
995 
997  st->codec->extradata_size * 8, 1) >= 0) {
998  st->codec->channels = cfg.channels;
999  st->codec->channel_layout = 0;
1000  if (cfg.ext_sample_rate)
1001  st->codec->sample_rate = cfg.ext_sample_rate;
1002  else
1003  st->codec->sample_rate = cfg.sample_rate;
1004  av_dlog(s, "mp4a config channels %d sample rate %d\n",
1005  st->codec->channels, st->codec->sample_rate);
1006  }
1007  }
1008 
1009  ret = AVERROR(EAGAIN);
1010  goto leave;
1011  }
1012  }
1013 
1014  /* skip empty data packets */
1015  if (!size) {
1016  ret = AVERROR(EAGAIN);
1017  goto leave;
1018  }
1019 
1020  ret = av_get_packet(s->pb, pkt, size);
1021  if (ret < 0)
1022  return ret;
1023  pkt->dts = dts;
1024  pkt->pts = pts == AV_NOPTS_VALUE ? dts : pts;
1025  pkt->stream_index = st->index;
1026  if (flv->new_extradata[stream_type]) {
1028  flv->new_extradata_size[stream_type]);
1029  if (side) {
1030  memcpy(side, flv->new_extradata[stream_type],
1031  flv->new_extradata_size[stream_type]);
1032  av_freep(&flv->new_extradata[stream_type]);
1033  flv->new_extradata_size[stream_type] = 0;
1034  }
1035  }
1036  if (stream_type == FLV_STREAM_TYPE_AUDIO &&
1037  (sample_rate != flv->last_sample_rate ||
1038  channels != flv->last_channels)) {
1040  flv->last_channels = channels;
1041  ff_add_param_change(pkt, channels, 0, sample_rate, 0, 0);
1042  }
1043 
1044  if ( stream_type == FLV_STREAM_TYPE_AUDIO ||
1045  ((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_KEY) ||
1046  stream_type == FLV_STREAM_TYPE_DATA)
1047  pkt->flags |= AV_PKT_FLAG_KEY;
1048 
1049 leave:
1050  avio_skip(s->pb, 4);
1051  return ret;
1052 }
1053 
1054 static int flv_read_seek(AVFormatContext *s, int stream_index,
1055  int64_t ts, int flags)
1056 {
1057  FLVContext *flv = s->priv_data;
1058  flv->validate_count = 0;
1059  return avio_seek_time(s->pb, stream_index, ts, flags);
1060 }
1061 
1062 #define OFFSET(x) offsetof(FLVContext, x)
1063 #define VD AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_DECODING_PARAM
1064 static const AVOption options[] = {
1065  { "flv_metadata", "Allocate streams according to the onMetaData array", OFFSET(trust_metadata), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, VD },
1066  { NULL }
1067 };
1068 
1069 static const AVClass flv_class = {
1070  .class_name = "flvdec",
1071  .item_name = av_default_item_name,
1072  .option = options,
1073  .version = LIBAVUTIL_VERSION_INT,
1074 };
1075 
1077  .name = "flv",
1078  .long_name = NULL_IF_CONFIG_SMALL("FLV (Flash Video)"),
1079  .priv_data_size = sizeof(FLVContext),
1080  .read_probe = flv_probe,
1085  .extensions = "flv",
1086  .priv_class = &flv_class,
1087 };
1088 
1089 static const AVClass live_flv_class = {
1090  .class_name = "live_flvdec",
1091  .item_name = av_default_item_name,
1092  .option = options,
1093  .version = LIBAVUTIL_VERSION_INT,
1094 };
1095 
1097  .name = "live_flv",
1098  .long_name = NULL_IF_CONFIG_SMALL("live RTMP FLV (Flash Video)"),
1099  .priv_data_size = sizeof(FLVContext),
1105  .extensions = "flv",
1106  .priv_class = &live_flv_class,
1108 };