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flvenc.c
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1 /*
2  * FLV muxer
3  * Copyright (c) 2003 The FFmpeg Project
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/intreadwrite.h"
23 #include "libavutil/dict.h"
24 #include "libavutil/intfloat.h"
25 #include "libavutil/avassert.h"
26 #include "avc.h"
27 #include "avformat.h"
28 #include "flv.h"
29 #include "internal.h"
30 #include "metadata.h"
31 
32 
33 static const AVCodecTag flv_video_codec_ids[] = {
43  { AV_CODEC_ID_NONE, 0 }
44 };
45 
46 static const AVCodecTag flv_audio_codec_ids[] = {
57  { AV_CODEC_ID_NONE, 0 }
58 };
59 
60 typedef struct FLVContext {
61  int reserved;
62  int64_t duration_offset;
63  int64_t filesize_offset;
64  int64_t duration;
65  int64_t delay; ///< first dts delay (needed for AVC & Speex)
66 } FLVContext;
67 
68 typedef struct FLVStreamContext {
69  int64_t last_ts; ///< last timestamp for each stream
71 
73 {
76 
77  if (enc->codec_id == AV_CODEC_ID_AAC) // specs force these parameters
80  else if (enc->codec_id == AV_CODEC_ID_SPEEX) {
81  if (enc->sample_rate != 16000) {
83  "FLV only supports wideband (16kHz) Speex audio\n");
84  return AVERROR(EINVAL);
85  }
86  if (enc->channels != 1) {
87  av_log(s, AV_LOG_ERROR, "FLV only supports mono Speex audio\n");
88  return AVERROR(EINVAL);
89  }
91  } else {
92  switch (enc->sample_rate) {
93  case 44100:
94  flags |= FLV_SAMPLERATE_44100HZ;
95  break;
96  case 22050:
97  flags |= FLV_SAMPLERATE_22050HZ;
98  break;
99  case 11025:
100  flags |= FLV_SAMPLERATE_11025HZ;
101  break;
102  case 16000: // nellymoser only
103  case 8000: // nellymoser only
104  case 5512: // not MP3
105  if (enc->codec_id != AV_CODEC_ID_MP3) {
106  flags |= FLV_SAMPLERATE_SPECIAL;
107  break;
108  }
109  default:
110  av_log(s, AV_LOG_ERROR,
111  "FLV does not support sample rate %d, "
112  "choose from (44100, 22050, 11025)\n", enc->sample_rate);
113  return AVERROR(EINVAL);
114  }
115  }
116 
117  if (enc->channels > 1)
118  flags |= FLV_STEREO;
119 
120  switch (enc->codec_id) {
121  case AV_CODEC_ID_MP3:
123  break;
124  case AV_CODEC_ID_PCM_U8:
126  break;
129  break;
132  break;
135  break;
137  if (enc->sample_rate == 8000)
139  else if (enc->sample_rate == 16000)
141  else
143  break;
146  break;
149  break;
150  case 0:
151  flags |= enc->codec_tag << 4;
152  break;
153  default:
154  av_log(s, AV_LOG_ERROR, "Audio codec '%s' not compatible with FLV\n",
155  avcodec_get_name(enc->codec_id));
156  return AVERROR(EINVAL);
157  }
158 
159  return flags;
160 }
161 
162 static void put_amf_string(AVIOContext *pb, const char *str)
163 {
164  size_t len = strlen(str);
165  avio_wb16(pb, len);
166  avio_write(pb, str, len);
167 }
168 
169 static void put_avc_eos_tag(AVIOContext *pb, unsigned ts)
170 {
172  avio_wb24(pb, 5); /* Tag Data Size */
173  avio_wb24(pb, ts); /* lower 24 bits of timestamp in ms */
174  avio_w8(pb, (ts >> 24) & 0x7F); /* MSB of ts in ms */
175  avio_wb24(pb, 0); /* StreamId = 0 */
176  avio_w8(pb, 23); /* ub[4] FrameType = 1, ub[4] CodecId = 7 */
177  avio_w8(pb, 2); /* AVC end of sequence */
178  avio_wb24(pb, 0); /* Always 0 for AVC EOS. */
179  avio_wb32(pb, 16); /* Size of FLV tag */
180 }
181 
182 static void put_amf_double(AVIOContext *pb, double d)
183 {
185  avio_wb64(pb, av_double2int(d));
186 }
187 
188 static void put_amf_bool(AVIOContext *pb, int b)
189 {
191  avio_w8(pb, !!b);
192 }
193 
195 {
196  AVIOContext *pb = s->pb;
197  FLVContext *flv = s->priv_data;
198  AVCodecContext *audio_enc = NULL, *video_enc = NULL, *data_enc = NULL;
199  int i, metadata_count = 0;
200  double framerate = 0.0;
201  int64_t metadata_size_pos, data_size, metadata_count_pos;
202  AVDictionaryEntry *tag = NULL;
203 
204  for (i = 0; i < s->nb_streams; i++) {
205  AVCodecContext *enc = s->streams[i]->codec;
206  FLVStreamContext *sc;
207  switch (enc->codec_type) {
208  case AVMEDIA_TYPE_VIDEO:
209  if (s->streams[i]->avg_frame_rate.den &&
210  s->streams[i]->avg_frame_rate.num) {
211  framerate = av_q2d(s->streams[i]->avg_frame_rate);
212  }
213  if (video_enc) {
214  av_log(s, AV_LOG_ERROR,
215  "at most one video stream is supported in flv\n");
216  return AVERROR(EINVAL);
217  }
218  video_enc = enc;
219  if (enc->codec_tag == 0) {
220  av_log(s, AV_LOG_ERROR, "Video codec '%s' for stream %d is not compatible with FLV\n",
221  avcodec_get_name(enc->codec_id), i);
222  return AVERROR(EINVAL);
223  }
224  if (enc->codec_id == AV_CODEC_ID_MPEG4 ||
225  enc->codec_id == AV_CODEC_ID_H263) {
227  av_log(s, error ? AV_LOG_ERROR : AV_LOG_WARNING,
228  "Codec %s is not supported in the official FLV specification,\n", avcodec_get_name(enc->codec_id));
229 
230  if (error) {
231  av_log(s, AV_LOG_ERROR,
232  "use vstrict=-1 / -strict -1 to use it anyway.\n");
233  return AVERROR(EINVAL);
234  }
235  }
236  break;
237  case AVMEDIA_TYPE_AUDIO:
238  if (audio_enc) {
239  av_log(s, AV_LOG_ERROR,
240  "at most one audio stream is supported in flv\n");
241  return AVERROR(EINVAL);
242  }
243  audio_enc = enc;
244  if (get_audio_flags(s, enc) < 0)
245  return AVERROR_INVALIDDATA;
246  if (enc->codec_id == AV_CODEC_ID_PCM_S16BE)
248  "16-bit big-endian audio in flv is valid but most likely unplayable (hardware dependent); use s16le\n");
249  break;
250  case AVMEDIA_TYPE_DATA:
251  if (enc->codec_id != AV_CODEC_ID_TEXT && enc->codec_id != AV_CODEC_ID_NONE) {
252  av_log(s, AV_LOG_ERROR, "Data codec '%s' for stream %d is not compatible with FLV\n",
253  avcodec_get_name(enc->codec_id), i);
254  return AVERROR_INVALIDDATA;
255  }
256  data_enc = enc;
257  break;
258  default:
259  av_log(s, AV_LOG_ERROR, "Codec type '%s' for stream %d is not compatible with FLV\n",
261  return AVERROR(EINVAL);
262  }
263  avpriv_set_pts_info(s->streams[i], 32, 1, 1000); /* 32 bit pts in ms */
264 
265  sc = av_mallocz(sizeof(FLVStreamContext));
266  if (!sc)
267  return AVERROR(ENOMEM);
268  s->streams[i]->priv_data = sc;
269  sc->last_ts = -1;
270  }
271 
272  flv->delay = AV_NOPTS_VALUE;
273 
274  avio_write(pb, "FLV", 3);
275  avio_w8(pb, 1);
276  avio_w8(pb, FLV_HEADER_FLAG_HASAUDIO * !!audio_enc +
277  FLV_HEADER_FLAG_HASVIDEO * !!video_enc);
278  avio_wb32(pb, 9);
279  avio_wb32(pb, 0);
280 
281  for (i = 0; i < s->nb_streams; i++)
282  if (s->streams[i]->codec->codec_tag == 5) {
283  avio_w8(pb, 8); // message type
284  avio_wb24(pb, 0); // include flags
285  avio_wb24(pb, 0); // time stamp
286  avio_wb32(pb, 0); // reserved
287  avio_wb32(pb, 11); // size
288  flv->reserved = 5;
289  }
290 
291  /* write meta_tag */
292  avio_w8(pb, 18); // tag type META
293  metadata_size_pos = avio_tell(pb);
294  avio_wb24(pb, 0); // size of data part (sum of all parts below)
295  avio_wb24(pb, 0); // timestamp
296  avio_wb32(pb, 0); // reserved
297 
298  /* now data of data_size size */
299 
300  /* first event name as a string */
302  put_amf_string(pb, "onMetaData"); // 12 bytes
303 
304  /* mixed array (hash) with size and string/type/data tuples */
306  metadata_count_pos = avio_tell(pb);
307  metadata_count = 4 * !!video_enc +
308  5 * !!audio_enc +
309  1 * !!data_enc +
310  2; // +2 for duration and file size
311 
312  avio_wb32(pb, metadata_count);
313 
314  put_amf_string(pb, "duration");
315  flv->duration_offset= avio_tell(pb);
316 
317  // fill in the guessed duration, it'll be corrected later if incorrect
319 
320  if (video_enc) {
321  put_amf_string(pb, "width");
322  put_amf_double(pb, video_enc->width);
323 
324  put_amf_string(pb, "height");
325  put_amf_double(pb, video_enc->height);
326 
327  put_amf_string(pb, "videodatarate");
328  put_amf_double(pb, video_enc->bit_rate / 1024.0);
329 
330  if (framerate != 0.0) {
331  put_amf_string(pb, "framerate");
332  put_amf_double(pb, framerate);
333  metadata_count++;
334  }
335 
336  put_amf_string(pb, "videocodecid");
337  put_amf_double(pb, video_enc->codec_tag);
338  }
339 
340  if (audio_enc) {
341  put_amf_string(pb, "audiodatarate");
342  put_amf_double(pb, audio_enc->bit_rate / 1024.0);
343 
344  put_amf_string(pb, "audiosamplerate");
345  put_amf_double(pb, audio_enc->sample_rate);
346 
347  put_amf_string(pb, "audiosamplesize");
348  put_amf_double(pb, audio_enc->codec_id == AV_CODEC_ID_PCM_U8 ? 8 : 16);
349 
350  put_amf_string(pb, "stereo");
351  put_amf_bool(pb, audio_enc->channels == 2);
352 
353  put_amf_string(pb, "audiocodecid");
354  put_amf_double(pb, audio_enc->codec_tag);
355  }
356 
357  if (data_enc) {
358  put_amf_string(pb, "datastream");
359  put_amf_double(pb, 0.0);
360  }
361 
362  while ((tag = av_dict_get(s->metadata, "", tag, AV_DICT_IGNORE_SUFFIX))) {
363  if( !strcmp(tag->key, "width")
364  ||!strcmp(tag->key, "height")
365  ||!strcmp(tag->key, "videodatarate")
366  ||!strcmp(tag->key, "framerate")
367  ||!strcmp(tag->key, "videocodecid")
368  ||!strcmp(tag->key, "audiodatarate")
369  ||!strcmp(tag->key, "audiosamplerate")
370  ||!strcmp(tag->key, "audiosamplesize")
371  ||!strcmp(tag->key, "stereo")
372  ||!strcmp(tag->key, "audiocodecid")
373  ||!strcmp(tag->key, "duration")
374  ||!strcmp(tag->key, "onMetaData")
375  ){
376  av_log(s, AV_LOG_DEBUG, "Ignoring metadata for %s\n", tag->key);
377  continue;
378  }
379  put_amf_string(pb, tag->key);
381  put_amf_string(pb, tag->value);
382  metadata_count++;
383  }
384 
385  put_amf_string(pb, "filesize");
386  flv->filesize_offset = avio_tell(pb);
387  put_amf_double(pb, 0); // delayed write
388 
389  put_amf_string(pb, "");
391 
392  /* write total size of tag */
393  data_size = avio_tell(pb) - metadata_size_pos - 10;
394 
395  avio_seek(pb, metadata_count_pos, SEEK_SET);
396  avio_wb32(pb, metadata_count);
397 
398  avio_seek(pb, metadata_size_pos, SEEK_SET);
399  avio_wb24(pb, data_size);
400  avio_skip(pb, data_size + 10 - 3);
401  avio_wb32(pb, data_size + 11);
402 
403  for (i = 0; i < s->nb_streams; i++) {
404  AVCodecContext *enc = s->streams[i]->codec;
405  if (enc->codec_id == AV_CODEC_ID_AAC || enc->codec_id == AV_CODEC_ID_H264 || enc->codec_id == AV_CODEC_ID_MPEG4) {
406  int64_t pos;
409  avio_wb24(pb, 0); // size patched later
410  avio_wb24(pb, 0); // ts
411  avio_w8(pb, 0); // ts ext
412  avio_wb24(pb, 0); // streamid
413  pos = avio_tell(pb);
414  if (enc->codec_id == AV_CODEC_ID_AAC) {
415  avio_w8(pb, get_audio_flags(s, enc));
416  avio_w8(pb, 0); // AAC sequence header
417  avio_write(pb, enc->extradata, enc->extradata_size);
418  } else {
419  avio_w8(pb, enc->codec_tag | FLV_FRAME_KEY); // flags
420  avio_w8(pb, 0); // AVC sequence header
421  avio_wb24(pb, 0); // composition time
423  }
424  data_size = avio_tell(pb) - pos;
425  avio_seek(pb, -data_size - 10, SEEK_CUR);
426  avio_wb24(pb, data_size);
427  avio_skip(pb, data_size + 10 - 3);
428  avio_wb32(pb, data_size + 11); // previous tag size
429  }
430  }
431 
432  return 0;
433 }
434 
436 {
437  int64_t file_size;
438 
439  AVIOContext *pb = s->pb;
440  FLVContext *flv = s->priv_data;
441  int i;
442 
443  /* Add EOS tag */
444  for (i = 0; i < s->nb_streams; i++) {
445  AVCodecContext *enc = s->streams[i]->codec;
446  FLVStreamContext *sc = s->streams[i]->priv_data;
447  if (enc->codec_type == AVMEDIA_TYPE_VIDEO &&
449  put_avc_eos_tag(pb, sc->last_ts);
450  }
451 
452  file_size = avio_tell(pb);
453 
454  /* update information */
455  if (avio_seek(pb, flv->duration_offset, SEEK_SET) < 0)
456  av_log(s, AV_LOG_WARNING, "Failed to update header with correct duration.\n");
457  else
458  put_amf_double(pb, flv->duration / (double)1000);
459  if (avio_seek(pb, flv->filesize_offset, SEEK_SET) < 0)
460  av_log(s, AV_LOG_WARNING, "Failed to update header with correct filesize.\n");
461  else
462  put_amf_double(pb, file_size);
463 
464  avio_seek(pb, file_size, SEEK_SET);
465  return 0;
466 }
467 
469 {
470  AVIOContext *pb = s->pb;
471  AVCodecContext *enc = s->streams[pkt->stream_index]->codec;
472  FLVContext *flv = s->priv_data;
474  unsigned ts;
475  int size = pkt->size;
476  uint8_t *data = NULL;
477  int flags = -1, flags_size, ret;
478 
479  if (enc->codec_id == AV_CODEC_ID_VP6F || enc->codec_id == AV_CODEC_ID_VP6A ||
481  flags_size = 2;
482  else if (enc->codec_id == AV_CODEC_ID_H264 || enc->codec_id == AV_CODEC_ID_MPEG4)
483  flags_size = 5;
484  else
485  flags_size = 1;
486 
487  switch (enc->codec_type) {
488  case AVMEDIA_TYPE_VIDEO:
490 
491  flags = enc->codec_tag;
492  if (flags == 0) {
493  av_log(s, AV_LOG_ERROR,
494  "Video codec '%s' is not compatible with FLV\n",
495  avcodec_get_name(enc->codec_id));
496  return AVERROR(EINVAL);
497  }
498 
500  break;
501  case AVMEDIA_TYPE_AUDIO:
502  flags = get_audio_flags(s, enc);
503 
504  av_assert0(size);
505 
507  break;
508  case AVMEDIA_TYPE_DATA:
510  break;
511  default:
512  return AVERROR(EINVAL);
513  }
514 
515  if (enc->codec_id == AV_CODEC_ID_H264 || enc->codec_id == AV_CODEC_ID_MPEG4) {
516  /* check if extradata looks like mp4 formated */
517  if (enc->extradata_size > 0 && *(uint8_t*)enc->extradata != 1)
518  if ((ret = ff_avc_parse_nal_units_buf(pkt->data, &data, &size)) < 0)
519  return ret;
520  } else if (enc->codec_id == AV_CODEC_ID_AAC && pkt->size > 2 &&
521  (AV_RB16(pkt->data) & 0xfff0) == 0xfff0) {
522  if (!s->streams[pkt->stream_index]->nb_frames) {
523  av_log(s, AV_LOG_ERROR, "Malformed AAC bitstream detected: "
524  "use the audio bitstream filter 'aac_adtstoasc' to fix it "
525  "('-bsf:a aac_adtstoasc' option with ffmpeg)\n");
526  return AVERROR_INVALIDDATA;
527  }
528  av_log(s, AV_LOG_WARNING, "aac bitstream error\n");
529  }
530 
531  if (flv->delay == AV_NOPTS_VALUE)
532  flv->delay = -pkt->dts;
533 
534  if (pkt->dts < -flv->delay) {
536  "Packets are not in the proper order with respect to DTS\n");
537  return AVERROR(EINVAL);
538  }
539 
540  ts = pkt->dts + flv->delay; // add delay to force positive dts
541 
542  /* check Speex packet duration */
543  if (enc->codec_id == AV_CODEC_ID_SPEEX && ts - sc->last_ts > 160)
544  av_log(s, AV_LOG_WARNING, "Warning: Speex stream has more than "
545  "8 frames per packet. Adobe Flash "
546  "Player cannot handle this!\n");
547 
548  if (sc->last_ts < ts)
549  sc->last_ts = ts;
550 
551  avio_wb24(pb, size + flags_size);
552  avio_wb24(pb, ts & 0xFFFFFF);
553  avio_w8(pb, (ts >> 24) & 0x7F); // timestamps are 32 bits _signed_
554  avio_wb24(pb, flv->reserved);
555 
556  if (enc->codec_type == AVMEDIA_TYPE_DATA) {
557  int data_size;
558  int64_t metadata_size_pos = avio_tell(pb);
559  if (enc->codec_id == AV_CODEC_ID_TEXT) {
560  // legacy FFmpeg magic?
562  put_amf_string(pb, "onTextData");
564  avio_wb32(pb, 2);
565  put_amf_string(pb, "type");
567  put_amf_string(pb, "Text");
568  put_amf_string(pb, "text");
570  put_amf_string(pb, pkt->data);
571  put_amf_string(pb, "");
573  } else {
574  // just pass the metadata through
575  avio_write(pb, data ? data : pkt->data, size);
576  }
577  /* write total size of tag */
578  data_size = avio_tell(pb) - metadata_size_pos;
579  avio_seek(pb, metadata_size_pos - 10, SEEK_SET);
580  avio_wb24(pb, data_size);
581  avio_seek(pb, data_size + 10 - 3, SEEK_CUR);
582  avio_wb32(pb, data_size + 11);
583  } else {
584  av_assert1(flags>=0);
585  avio_w8(pb,flags);
586  if (enc->codec_id == AV_CODEC_ID_VP6)
587  avio_w8(pb,0);
588  if (enc->codec_id == AV_CODEC_ID_VP6F || enc->codec_id == AV_CODEC_ID_VP6A) {
589  if (enc->extradata_size)
590  avio_w8(pb, enc->extradata[0]);
591  else
592  avio_w8(pb, ((FFALIGN(enc->width, 16) - enc->width) << 4) |
593  (FFALIGN(enc->height, 16) - enc->height));
594  } else if (enc->codec_id == AV_CODEC_ID_AAC)
595  avio_w8(pb, 1); // AAC raw
596  else if (enc->codec_id == AV_CODEC_ID_H264 || enc->codec_id == AV_CODEC_ID_MPEG4) {
597  avio_w8(pb, 1); // AVC NALU
598  avio_wb24(pb, pkt->pts - pkt->dts);
599  }
600 
601  avio_write(pb, data ? data : pkt->data, size);
602 
603  avio_wb32(pb, size + flags_size + 11); // previous tag size
604  flv->duration = FFMAX(flv->duration,
605  pkt->pts + flv->delay + pkt->duration);
606  }
607 
608  av_free(data);
609 
610  return pb->error;
611 }
612 
614  .name = "flv",
615  .long_name = NULL_IF_CONFIG_SMALL("FLV (Flash Video)"),
616  .mime_type = "video/x-flv",
617  .extensions = "flv",
618  .priv_data_size = sizeof(FLVContext),
619  .audio_codec = CONFIG_LIBMP3LAME ? AV_CODEC_ID_MP3 : AV_CODEC_ID_ADPCM_SWF,
620  .video_codec = AV_CODEC_ID_FLV1,
624  .codec_tag = (const AVCodecTag* const []) {
626  },
629 };