FFmpeg  1.2.12
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;
66 } FLVContext;
67 
68 typedef struct FLVStreamContext {
69  int64_t last_ts;
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;
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  } else {
213  framerate = 1 / av_q2d(s->streams[i]->codec->time_base);
214  }
215  video_enc = enc;
216  if (enc->codec_tag == 0) {
217  av_log(s, AV_LOG_ERROR, "Video codec '%s' for stream %d is not compatible with FLV\n",
218  avcodec_get_name(enc->codec_id), i);
219  return AVERROR(EINVAL);
220  }
221  if (enc->codec_id == AV_CODEC_ID_MPEG4 ||
222  enc->codec_id == AV_CODEC_ID_H263) {
224  av_log(s, error ? AV_LOG_ERROR : AV_LOG_WARNING,
225  "Codec %s is not supported in the official FLV specification,\n", avcodec_get_name(enc->codec_id));
226 
227  if (error) {
228  av_log(s, AV_LOG_ERROR,
229  "use vstrict=-1 / -strict -1 to use it anyway.\n");
230  return AVERROR(EINVAL);
231  }
232  }
233  break;
234  case AVMEDIA_TYPE_AUDIO:
235  audio_enc = enc;
236  if (get_audio_flags(s, enc) < 0)
237  return AVERROR_INVALIDDATA;
238  break;
239  case AVMEDIA_TYPE_DATA:
240  if (enc->codec_id != AV_CODEC_ID_TEXT) {
241  av_log(s, AV_LOG_ERROR, "Data codec '%s' for stream %d is not compatible with FLV\n",
242  avcodec_get_name(enc->codec_id), i);
243  return AVERROR_INVALIDDATA;
244  }
245  data_enc = enc;
246  break;
247  default:
248  av_log(s, AV_LOG_ERROR, "Codec type '%s' for stream %d is not compatible with FLV\n",
250  return AVERROR(EINVAL);
251  }
252  avpriv_set_pts_info(s->streams[i], 32, 1, 1000); /* 32 bit pts in ms */
253 
254  sc = av_mallocz(sizeof(FLVStreamContext));
255  if (!sc)
256  return AVERROR(ENOMEM);
257  s->streams[i]->priv_data = sc;
258  sc->last_ts = -1;
259  }
260 
261  flv->delay = AV_NOPTS_VALUE;
262 
263  avio_write(pb, "FLV", 3);
264  avio_w8(pb, 1);
265  avio_w8(pb, FLV_HEADER_FLAG_HASAUDIO * !!audio_enc +
266  FLV_HEADER_FLAG_HASVIDEO * !!video_enc);
267  avio_wb32(pb, 9);
268  avio_wb32(pb, 0);
269 
270  for (i = 0; i < s->nb_streams; i++)
271  if (s->streams[i]->codec->codec_tag == 5) {
272  avio_w8(pb, 8); // message type
273  avio_wb24(pb, 0); // include flags
274  avio_wb24(pb, 0); // time stamp
275  avio_wb32(pb, 0); // reserved
276  avio_wb32(pb, 11); // size
277  flv->reserved = 5;
278  }
279 
280  /* write meta_tag */
281  avio_w8(pb, 18); // tag type META
282  metadata_size_pos = avio_tell(pb);
283  avio_wb24(pb, 0); // size of data part (sum of all parts below)
284  avio_wb24(pb, 0); // timestamp
285  avio_wb32(pb, 0); // reserved
286 
287  /* now data of data_size size */
288 
289  /* first event name as a string */
291  put_amf_string(pb, "onMetaData"); // 12 bytes
292 
293  /* mixed array (hash) with size and string/type/data tuples */
295  metadata_count_pos = avio_tell(pb);
296  metadata_count = 5 * !!video_enc +
297  5 * !!audio_enc +
298  1 * !!data_enc +
299  2; // +2 for duration and file size
300 
301  avio_wb32(pb, metadata_count);
302 
303  put_amf_string(pb, "duration");
304  flv->duration_offset= avio_tell(pb);
305 
306  // fill in the guessed duration, it'll be corrected later if incorrect
308 
309  if (video_enc) {
310  put_amf_string(pb, "width");
311  put_amf_double(pb, video_enc->width);
312 
313  put_amf_string(pb, "height");
314  put_amf_double(pb, video_enc->height);
315 
316  put_amf_string(pb, "videodatarate");
317  put_amf_double(pb, video_enc->bit_rate / 1024.0);
318 
319  put_amf_string(pb, "framerate");
320  put_amf_double(pb, framerate);
321 
322  put_amf_string(pb, "videocodecid");
323  put_amf_double(pb, video_enc->codec_tag);
324  }
325 
326  if (audio_enc) {
327  put_amf_string(pb, "audiodatarate");
328  put_amf_double(pb, audio_enc->bit_rate / 1024.0);
329 
330  put_amf_string(pb, "audiosamplerate");
331  put_amf_double(pb, audio_enc->sample_rate);
332 
333  put_amf_string(pb, "audiosamplesize");
334  put_amf_double(pb, audio_enc->codec_id == AV_CODEC_ID_PCM_U8 ? 8 : 16);
335 
336  put_amf_string(pb, "stereo");
337  put_amf_bool(pb, audio_enc->channels == 2);
338 
339  put_amf_string(pb, "audiocodecid");
340  put_amf_double(pb, audio_enc->codec_tag);
341  }
342 
343  if (data_enc) {
344  put_amf_string(pb, "datastream");
345  put_amf_double(pb, 0.0);
346  }
347 
348  while ((tag = av_dict_get(s->metadata, "", tag, AV_DICT_IGNORE_SUFFIX))) {
349  if( !strcmp(tag->key, "width")
350  ||!strcmp(tag->key, "height")
351  ||!strcmp(tag->key, "videodatarate")
352  ||!strcmp(tag->key, "framerate")
353  ||!strcmp(tag->key, "videocodecid")
354  ||!strcmp(tag->key, "audiodatarate")
355  ||!strcmp(tag->key, "audiosamplerate")
356  ||!strcmp(tag->key, "audiosamplesize")
357  ||!strcmp(tag->key, "stereo")
358  ||!strcmp(tag->key, "audiocodecid")
359  ||!strcmp(tag->key, "duration")
360  ||!strcmp(tag->key, "onMetaData")
361  ){
362  av_log(s, AV_LOG_DEBUG, "Ignoring metadata for %s\n", tag->key);
363  continue;
364  }
365  put_amf_string(pb, tag->key);
367  put_amf_string(pb, tag->value);
368  metadata_count++;
369  }
370 
371  put_amf_string(pb, "filesize");
372  flv->filesize_offset = avio_tell(pb);
373  put_amf_double(pb, 0); // delayed write
374 
375  put_amf_string(pb, "");
377 
378  /* write total size of tag */
379  data_size = avio_tell(pb) - metadata_size_pos - 10;
380 
381  avio_seek(pb, metadata_count_pos, SEEK_SET);
382  avio_wb32(pb, metadata_count);
383 
384  avio_seek(pb, metadata_size_pos, SEEK_SET);
385  avio_wb24(pb, data_size);
386  avio_skip(pb, data_size + 10 - 3);
387  avio_wb32(pb, data_size + 11);
388 
389  for (i = 0; i < s->nb_streams; i++) {
390  AVCodecContext *enc = s->streams[i]->codec;
391  if (enc->codec_id == AV_CODEC_ID_AAC || enc->codec_id == AV_CODEC_ID_H264 || enc->codec_id == AV_CODEC_ID_MPEG4) {
392  int64_t pos;
395  avio_wb24(pb, 0); // size patched later
396  avio_wb24(pb, 0); // ts
397  avio_w8(pb, 0); // ts ext
398  avio_wb24(pb, 0); // streamid
399  pos = avio_tell(pb);
400  if (enc->codec_id == AV_CODEC_ID_AAC) {
401  avio_w8(pb, get_audio_flags(s, enc));
402  avio_w8(pb, 0); // AAC sequence header
403  avio_write(pb, enc->extradata, enc->extradata_size);
404  } else {
405  avio_w8(pb, enc->codec_tag | FLV_FRAME_KEY); // flags
406  avio_w8(pb, 0); // AVC sequence header
407  avio_wb24(pb, 0); // composition time
409  }
410  data_size = avio_tell(pb) - pos;
411  avio_seek(pb, -data_size - 10, SEEK_CUR);
412  avio_wb24(pb, data_size);
413  avio_skip(pb, data_size + 10 - 3);
414  avio_wb32(pb, data_size + 11); // previous tag size
415  }
416  }
417 
418  return 0;
419 }
420 
422 {
423  int64_t file_size;
424 
425  AVIOContext *pb = s->pb;
426  FLVContext *flv = s->priv_data;
427  int i;
428 
429  /* Add EOS tag */
430  for (i = 0; i < s->nb_streams; i++) {
431  AVCodecContext *enc = s->streams[i]->codec;
432  FLVStreamContext *sc = s->streams[i]->priv_data;
433  if (enc->codec_type == AVMEDIA_TYPE_VIDEO &&
435  put_avc_eos_tag(pb, sc->last_ts);
436  }
437 
438  file_size = avio_tell(pb);
439 
440  /* update information */
441  if (avio_seek(pb, flv->duration_offset, SEEK_SET) < 0)
442  av_log(s, AV_LOG_WARNING, "Failed to update header with correct duration.\n");
443  else
444  put_amf_double(pb, flv->duration / (double)1000);
445  if (avio_seek(pb, flv->filesize_offset, SEEK_SET) < 0)
446  av_log(s, AV_LOG_WARNING, "Failed to update header with correct filesize.\n");
447  else
448  put_amf_double(pb, file_size);
449 
450  avio_seek(pb, file_size, SEEK_SET);
451  return 0;
452 }
453 
455 {
456  AVIOContext *pb = s->pb;
457  AVCodecContext *enc = s->streams[pkt->stream_index]->codec;
458  FLVContext *flv = s->priv_data;
460  unsigned ts;
461  int size = pkt->size;
462  uint8_t *data = NULL;
463  int flags = -1, flags_size, ret;
464 
465  if (enc->codec_id == AV_CODEC_ID_VP6 || enc->codec_id == AV_CODEC_ID_VP6F ||
467  flags_size = 2;
468  else if (enc->codec_id == AV_CODEC_ID_H264 || enc->codec_id == AV_CODEC_ID_MPEG4)
469  flags_size = 5;
470  else
471  flags_size = 1;
472 
473  switch (enc->codec_type) {
474  case AVMEDIA_TYPE_VIDEO:
476 
477  flags = enc->codec_tag;
478  if (flags == 0) {
479  av_log(s, AV_LOG_ERROR,
480  "Video codec '%s' is not compatible with FLV\n",
481  avcodec_get_name(enc->codec_id));
482  return AVERROR(EINVAL);
483  }
484 
486  break;
487  case AVMEDIA_TYPE_AUDIO:
488  flags = get_audio_flags(s, enc);
489 
490  av_assert0(size);
491 
493  break;
494  case AVMEDIA_TYPE_DATA:
496  break;
497  default:
498  return AVERROR(EINVAL);
499  }
500 
501  if (enc->codec_id == AV_CODEC_ID_H264 || enc->codec_id == AV_CODEC_ID_MPEG4) {
502  /* check if extradata looks like mp4 formated */
503  if (enc->extradata_size > 0 && *(uint8_t*)enc->extradata != 1)
504  if ((ret = ff_avc_parse_nal_units_buf(pkt->data, &data, &size)) < 0)
505  return ret;
506  } else if (enc->codec_id == AV_CODEC_ID_AAC && pkt->size > 2 &&
507  (AV_RB16(pkt->data) & 0xfff0) == 0xfff0) {
508  if (!s->streams[pkt->stream_index]->nb_frames) {
509  av_log(s, AV_LOG_ERROR, "Malformed AAC bitstream detected: "
510  "use audio bitstream filter 'aac_adtstoasc' to fix it "
511  "('-bsf:a aac_adtstoasc' option with ffmpeg)\n");
512  return AVERROR_INVALIDDATA;
513  }
514  av_log(s, AV_LOG_WARNING, "aac bitstream error\n");
515  }
516 
517  if (flv->delay == AV_NOPTS_VALUE)
518  flv->delay = -pkt->dts;
519 
520  if (pkt->dts < -flv->delay) {
522  "Packets are not in the proper order with respect to DTS\n");
523  return AVERROR(EINVAL);
524  }
525 
526  ts = pkt->dts + flv->delay; // add delay to force positive dts
527 
528  /* check Speex packet duration */
529  if (enc->codec_id == AV_CODEC_ID_SPEEX && ts - sc->last_ts > 160)
530  av_log(s, AV_LOG_WARNING, "Warning: Speex stream has more than "
531  "8 frames per packet. Adobe Flash "
532  "Player cannot handle this!\n");
533 
534  if (sc->last_ts < ts)
535  sc->last_ts = ts;
536 
537  avio_wb24(pb, size + flags_size);
538  avio_wb24(pb, ts);
539  avio_w8(pb, (ts >> 24) & 0x7F); // timestamps are 32 bits _signed_
540  avio_wb24(pb, flv->reserved);
541 
542  if (enc->codec_type == AVMEDIA_TYPE_DATA) {
543  int data_size;
544  int metadata_size_pos = avio_tell(pb);
546  put_amf_string(pb, "onTextData");
548  avio_wb32(pb, 2);
549  put_amf_string(pb, "type");
551  put_amf_string(pb, "Text");
552  put_amf_string(pb, "text");
554  put_amf_string(pb, pkt->data);
555  put_amf_string(pb, "");
557  /* write total size of tag */
558  data_size = avio_tell(pb) - metadata_size_pos;
559  avio_seek(pb, metadata_size_pos - 10, SEEK_SET);
560  avio_wb24(pb, data_size);
561  avio_seek(pb, data_size + 10 - 3, SEEK_CUR);
562  avio_wb32(pb, data_size + 11);
563  } else {
564  av_assert1(flags>=0);
565  avio_w8(pb,flags);
566  if (enc->codec_id == AV_CODEC_ID_VP6)
567  avio_w8(pb,0);
568  if (enc->codec_id == AV_CODEC_ID_VP6F || enc->codec_id == AV_CODEC_ID_VP6A)
569  avio_w8(pb, enc->extradata_size ? enc->extradata[0] : 0);
570  else if (enc->codec_id == AV_CODEC_ID_AAC)
571  avio_w8(pb,1); // AAC raw
572  else if (enc->codec_id == AV_CODEC_ID_H264 || enc->codec_id == AV_CODEC_ID_MPEG4) {
573  avio_w8(pb,1); // AVC NALU
574  avio_wb24(pb,pkt->pts - pkt->dts);
575  }
576 
577  avio_write(pb, data ? data : pkt->data, size);
578 
579  avio_wb32(pb, size + flags_size + 11); // previous tag size
580  flv->duration = FFMAX(flv->duration,
581  pkt->pts + flv->delay + pkt->duration);
582  }
583 
584  avio_flush(pb);
585  av_free(data);
586 
587  return pb->error;
588 }
589 
591  .name = "flv",
592  .long_name = NULL_IF_CONFIG_SMALL("FLV (Flash Video)"),
593  .mime_type = "video/x-flv",
594  .extensions = "flv",
595  .priv_data_size = sizeof(FLVContext),
597  .video_codec = AV_CODEC_ID_FLV1,
601  .codec_tag = (const AVCodecTag* const []) {
603  },
606 };