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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[] = {
34  { AV_CODEC_ID_FLV1, FLV_CODECID_H263 },
35  { AV_CODEC_ID_H263, FLV_CODECID_REALH263 },
36  { AV_CODEC_ID_MPEG4, FLV_CODECID_MPEG4 },
37  { AV_CODEC_ID_FLASHSV, FLV_CODECID_SCREEN },
38  { AV_CODEC_ID_FLASHSV2, FLV_CODECID_SCREEN2 },
39  { AV_CODEC_ID_VP6F, FLV_CODECID_VP6 },
40  { AV_CODEC_ID_VP6, FLV_CODECID_VP6 },
41  { AV_CODEC_ID_VP6A, FLV_CODECID_VP6A },
42  { AV_CODEC_ID_H264, FLV_CODECID_H264 },
43  { AV_CODEC_ID_NONE, 0 }
44 };
45 
46 static const AVCodecTag flv_audio_codec_ids[] = {
47  { AV_CODEC_ID_MP3, FLV_CODECID_MP3 >> FLV_AUDIO_CODECID_OFFSET },
48  { AV_CODEC_ID_PCM_U8, FLV_CODECID_PCM >> FLV_AUDIO_CODECID_OFFSET },
49  { AV_CODEC_ID_PCM_S16BE, FLV_CODECID_PCM >> FLV_AUDIO_CODECID_OFFSET },
50  { AV_CODEC_ID_PCM_S16LE, FLV_CODECID_PCM_LE >> FLV_AUDIO_CODECID_OFFSET },
51  { AV_CODEC_ID_ADPCM_SWF, FLV_CODECID_ADPCM >> FLV_AUDIO_CODECID_OFFSET },
52  { AV_CODEC_ID_AAC, FLV_CODECID_AAC >> FLV_AUDIO_CODECID_OFFSET },
53  { AV_CODEC_ID_NELLYMOSER, FLV_CODECID_NELLYMOSER >> FLV_AUDIO_CODECID_OFFSET },
54  { AV_CODEC_ID_PCM_MULAW, FLV_CODECID_PCM_MULAW >> FLV_AUDIO_CODECID_OFFSET },
55  { AV_CODEC_ID_PCM_ALAW, FLV_CODECID_PCM_ALAW >> FLV_AUDIO_CODECID_OFFSET },
56  { AV_CODEC_ID_SPEEX, FLV_CODECID_SPEEX >> FLV_AUDIO_CODECID_OFFSET },
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
70 } FLVStreamContext;
71 
72 static int get_audio_flags(AVFormatContext *s, AVCodecContext *enc)
73 {
74  int flags = (enc->bits_per_coded_sample == 16) ? FLV_SAMPLESSIZE_16BIT
75  : FLV_SAMPLESSIZE_8BIT;
76 
77  if (enc->codec_id == AV_CODEC_ID_AAC) // specs force these parameters
78  return FLV_CODECID_AAC | FLV_SAMPLERATE_44100HZ |
79  FLV_SAMPLESSIZE_16BIT | FLV_STEREO;
80  else if (enc->codec_id == AV_CODEC_ID_SPEEX) {
81  if (enc->sample_rate != 16000) {
82  av_log(s, AV_LOG_ERROR,
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  }
90  return FLV_CODECID_SPEEX | FLV_SAMPLERATE_11025HZ | FLV_SAMPLESSIZE_16BIT;
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:
122  flags |= FLV_CODECID_MP3 | FLV_SAMPLESSIZE_16BIT;
123  break;
124  case AV_CODEC_ID_PCM_U8:
125  flags |= FLV_CODECID_PCM | FLV_SAMPLESSIZE_8BIT;
126  break;
127  case AV_CODEC_ID_PCM_S16BE:
128  flags |= FLV_CODECID_PCM | FLV_SAMPLESSIZE_16BIT;
129  break;
130  case AV_CODEC_ID_PCM_S16LE:
131  flags |= FLV_CODECID_PCM_LE | FLV_SAMPLESSIZE_16BIT;
132  break;
133  case AV_CODEC_ID_ADPCM_SWF:
134  flags |= FLV_CODECID_ADPCM | FLV_SAMPLESSIZE_16BIT;
135  break;
136  case AV_CODEC_ID_NELLYMOSER:
137  if (enc->sample_rate == 8000)
138  flags |= FLV_CODECID_NELLYMOSER_8KHZ_MONO | FLV_SAMPLESSIZE_16BIT;
139  else if (enc->sample_rate == 16000)
140  flags |= FLV_CODECID_NELLYMOSER_16KHZ_MONO | FLV_SAMPLESSIZE_16BIT;
141  else
142  flags |= FLV_CODECID_NELLYMOSER | FLV_SAMPLESSIZE_16BIT;
143  break;
144  case AV_CODEC_ID_PCM_MULAW:
145  flags = FLV_CODECID_PCM_MULAW | FLV_SAMPLERATE_SPECIAL | FLV_SAMPLESSIZE_16BIT;
146  break;
147  case AV_CODEC_ID_PCM_ALAW:
148  flags = FLV_CODECID_PCM_ALAW | FLV_SAMPLERATE_SPECIAL | FLV_SAMPLESSIZE_16BIT;
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 {
171  avio_w8(pb, FLV_TAG_TYPE_VIDEO);
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 {
184  avio_w8(pb, AMF_DATA_TYPE_NUMBER);
185  avio_wb64(pb, av_double2int(d));
186 }
187 
188 static void put_amf_bool(AVIOContext *pb, int b)
189 {
190  avio_w8(pb, AMF_DATA_TYPE_BOOL);
191  avio_w8(pb, !!b);
192 }
193 
194 static int flv_write_header(AVFormatContext *s)
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  } else {
213  framerate = 1 / av_q2d(s->streams[i]->codec->time_base);
214  }
215  if (video_enc) {
216  av_log(s, AV_LOG_ERROR,
217  "at most one video stream is supported in flv\n");
218  return AVERROR(EINVAL);
219  }
220  video_enc = enc;
221  if (enc->codec_tag == 0) {
222  av_log(s, AV_LOG_ERROR, "Video codec '%s' for stream %d is not compatible with FLV\n",
223  avcodec_get_name(enc->codec_id), i);
224  return AVERROR(EINVAL);
225  }
226  break;
227  case AVMEDIA_TYPE_AUDIO:
228  if (audio_enc) {
229  av_log(s, AV_LOG_ERROR,
230  "at most one audio stream is supported in flv\n");
231  return AVERROR(EINVAL);
232  }
233  audio_enc = enc;
234  if (get_audio_flags(s, enc) < 0)
235  return AVERROR_INVALIDDATA;
236  if (enc->codec_id == AV_CODEC_ID_PCM_S16BE)
237  av_log(s, AV_LOG_WARNING,
238  "16-bit big-endian audio in flv is valid but most likely unplayable (hardware dependent); use s16le\n");
239  break;
240  case AVMEDIA_TYPE_DATA:
241  if (enc->codec_id != AV_CODEC_ID_TEXT) {
242  av_log(s, AV_LOG_ERROR, "Data codec '%s' for stream %d is not compatible with FLV\n",
243  avcodec_get_name(enc->codec_id), i);
244  return AVERROR_INVALIDDATA;
245  }
246  data_enc = enc;
247  break;
248  default:
249  av_log(s, AV_LOG_ERROR, "Codec type '%s' for stream %d is not compatible with FLV\n",
250  av_get_media_type_string(enc->codec_type), i);
251  return AVERROR(EINVAL);
252  }
253  avpriv_set_pts_info(s->streams[i], 32, 1, 1000); /* 32 bit pts in ms */
254 
255  sc = av_mallocz(sizeof(FLVStreamContext));
256  if (!sc)
257  return AVERROR(ENOMEM);
258  s->streams[i]->priv_data = sc;
259  sc->last_ts = -1;
260  }
261 
262  flv->delay = AV_NOPTS_VALUE;
263 
264  avio_write(pb, "FLV", 3);
265  avio_w8(pb, 1);
266  avio_w8(pb, FLV_HEADER_FLAG_HASAUDIO * !!audio_enc +
267  FLV_HEADER_FLAG_HASVIDEO * !!video_enc);
268  avio_wb32(pb, 9);
269  avio_wb32(pb, 0);
270 
271  for (i = 0; i < s->nb_streams; i++)
272  if (s->streams[i]->codec->codec_tag == 5) {
273  avio_w8(pb, 8); // message type
274  avio_wb24(pb, 0); // include flags
275  avio_wb24(pb, 0); // time stamp
276  avio_wb32(pb, 0); // reserved
277  avio_wb32(pb, 11); // size
278  flv->reserved = 5;
279  }
280 
281  /* write meta_tag */
282  avio_w8(pb, 18); // tag type META
283  metadata_size_pos = avio_tell(pb);
284  avio_wb24(pb, 0); // size of data part (sum of all parts below)
285  avio_wb24(pb, 0); // timestamp
286  avio_wb32(pb, 0); // reserved
287 
288  /* now data of data_size size */
289 
290  /* first event name as a string */
291  avio_w8(pb, AMF_DATA_TYPE_STRING);
292  put_amf_string(pb, "onMetaData"); // 12 bytes
293 
294  /* mixed array (hash) with size and string/type/data tuples */
295  avio_w8(pb, AMF_DATA_TYPE_MIXEDARRAY);
296  metadata_count_pos = avio_tell(pb);
297  metadata_count = 5 * !!video_enc +
298  5 * !!audio_enc +
299  1 * !!data_enc +
300  2; // +2 for duration and file size
301 
302  avio_wb32(pb, metadata_count);
303 
304  put_amf_string(pb, "duration");
305  flv->duration_offset= avio_tell(pb);
306 
307  // fill in the guessed duration, it'll be corrected later if incorrect
308  put_amf_double(pb, s->duration / AV_TIME_BASE);
309 
310  if (video_enc) {
311  put_amf_string(pb, "width");
312  put_amf_double(pb, video_enc->width);
313 
314  put_amf_string(pb, "height");
315  put_amf_double(pb, video_enc->height);
316 
317  put_amf_string(pb, "videodatarate");
318  put_amf_double(pb, video_enc->bit_rate / 1024.0);
319 
320  put_amf_string(pb, "framerate");
321  put_amf_double(pb, framerate);
322 
323  put_amf_string(pb, "videocodecid");
324  put_amf_double(pb, video_enc->codec_tag);
325  }
326 
327  if (audio_enc) {
328  put_amf_string(pb, "audiodatarate");
329  put_amf_double(pb, audio_enc->bit_rate / 1024.0);
330 
331  put_amf_string(pb, "audiosamplerate");
332  put_amf_double(pb, audio_enc->sample_rate);
333 
334  put_amf_string(pb, "audiosamplesize");
335  put_amf_double(pb, audio_enc->codec_id == AV_CODEC_ID_PCM_U8 ? 8 : 16);
336 
337  put_amf_string(pb, "stereo");
338  put_amf_bool(pb, audio_enc->channels == 2);
339 
340  put_amf_string(pb, "audiocodecid");
341  put_amf_double(pb, audio_enc->codec_tag);
342  }
343 
344  if (data_enc) {
345  put_amf_string(pb, "datastream");
346  put_amf_double(pb, 0.0);
347  }
348 
349  while ((tag = av_dict_get(s->metadata, "", tag, AV_DICT_IGNORE_SUFFIX))) {
350  if( !strcmp(tag->key, "width")
351  ||!strcmp(tag->key, "height")
352  ||!strcmp(tag->key, "videodatarate")
353  ||!strcmp(tag->key, "framerate")
354  ||!strcmp(tag->key, "videocodecid")
355  ||!strcmp(tag->key, "audiodatarate")
356  ||!strcmp(tag->key, "audiosamplerate")
357  ||!strcmp(tag->key, "audiosamplesize")
358  ||!strcmp(tag->key, "stereo")
359  ||!strcmp(tag->key, "audiocodecid")
360  ||!strcmp(tag->key, "duration")
361  ||!strcmp(tag->key, "onMetaData")
362  ){
363  av_log(s, AV_LOG_DEBUG, "Ignoring metadata for %s\n", tag->key);
364  continue;
365  }
366  put_amf_string(pb, tag->key);
367  avio_w8(pb, AMF_DATA_TYPE_STRING);
368  put_amf_string(pb, tag->value);
369  metadata_count++;
370  }
371 
372  put_amf_string(pb, "filesize");
373  flv->filesize_offset = avio_tell(pb);
374  put_amf_double(pb, 0); // delayed write
375 
376  put_amf_string(pb, "");
377  avio_w8(pb, AMF_END_OF_OBJECT);
378 
379  /* write total size of tag */
380  data_size = avio_tell(pb) - metadata_size_pos - 10;
381 
382  avio_seek(pb, metadata_count_pos, SEEK_SET);
383  avio_wb32(pb, metadata_count);
384 
385  avio_seek(pb, metadata_size_pos, SEEK_SET);
386  avio_wb24(pb, data_size);
387  avio_skip(pb, data_size + 10 - 3);
388  avio_wb32(pb, data_size + 11);
389 
390  for (i = 0; i < s->nb_streams; i++) {
391  AVCodecContext *enc = s->streams[i]->codec;
392  if (enc->codec_id == AV_CODEC_ID_AAC || enc->codec_id == AV_CODEC_ID_H264 || enc->codec_id == AV_CODEC_ID_MPEG4) {
393  int64_t pos;
394  avio_w8(pb, enc->codec_type == AVMEDIA_TYPE_VIDEO ?
395  FLV_TAG_TYPE_VIDEO : FLV_TAG_TYPE_AUDIO);
396  avio_wb24(pb, 0); // size patched later
397  avio_wb24(pb, 0); // ts
398  avio_w8(pb, 0); // ts ext
399  avio_wb24(pb, 0); // streamid
400  pos = avio_tell(pb);
401  if (enc->codec_id == AV_CODEC_ID_AAC) {
402  avio_w8(pb, get_audio_flags(s, enc));
403  avio_w8(pb, 0); // AAC sequence header
404  avio_write(pb, enc->extradata, enc->extradata_size);
405  } else {
406  avio_w8(pb, enc->codec_tag | FLV_FRAME_KEY); // flags
407  avio_w8(pb, 0); // AVC sequence header
408  avio_wb24(pb, 0); // composition time
409  ff_isom_write_avcc(pb, enc->extradata, enc->extradata_size);
410  }
411  data_size = avio_tell(pb) - pos;
412  avio_seek(pb, -data_size - 10, SEEK_CUR);
413  avio_wb24(pb, data_size);
414  avio_skip(pb, data_size + 10 - 3);
415  avio_wb32(pb, data_size + 11); // previous tag size
416  }
417  }
418 
419  return 0;
420 }
421 
422 static int flv_write_trailer(AVFormatContext *s)
423 {
424  int64_t file_size;
425 
426  AVIOContext *pb = s->pb;
427  FLVContext *flv = s->priv_data;
428  int i;
429 
430  /* Add EOS tag */
431  for (i = 0; i < s->nb_streams; i++) {
432  AVCodecContext *enc = s->streams[i]->codec;
433  FLVStreamContext *sc = s->streams[i]->priv_data;
434  if (enc->codec_type == AVMEDIA_TYPE_VIDEO &&
435  (enc->codec_id == AV_CODEC_ID_H264 || enc->codec_id == AV_CODEC_ID_MPEG4))
436  put_avc_eos_tag(pb, sc->last_ts);
437  }
438 
439  file_size = avio_tell(pb);
440 
441  /* update information */
442  if (avio_seek(pb, flv->duration_offset, SEEK_SET) < 0)
443  av_log(s, AV_LOG_WARNING, "Failed to update header with correct duration.\n");
444  else
445  put_amf_double(pb, flv->duration / (double)1000);
446  if (avio_seek(pb, flv->filesize_offset, SEEK_SET) < 0)
447  av_log(s, AV_LOG_WARNING, "Failed to update header with correct filesize.\n");
448  else
449  put_amf_double(pb, file_size);
450 
451  avio_seek(pb, file_size, SEEK_SET);
452  return 0;
453 }
454 
455 static int flv_write_packet(AVFormatContext *s, AVPacket *pkt)
456 {
457  AVIOContext *pb = s->pb;
458  AVCodecContext *enc = s->streams[pkt->stream_index]->codec;
459  FLVContext *flv = s->priv_data;
460  FLVStreamContext *sc = s->streams[pkt->stream_index]->priv_data;
461  unsigned ts;
462  int size = pkt->size;
463  uint8_t *data = NULL;
464  int flags = -1, flags_size, ret;
465 
466  if (enc->codec_id == AV_CODEC_ID_VP6F || enc->codec_id == AV_CODEC_ID_VP6A ||
467  enc->codec_id == AV_CODEC_ID_VP6 || enc->codec_id == AV_CODEC_ID_AAC)
468  flags_size = 2;
469  else if (enc->codec_id == AV_CODEC_ID_H264 || enc->codec_id == AV_CODEC_ID_MPEG4)
470  flags_size = 5;
471  else
472  flags_size = 1;
473 
474  switch (enc->codec_type) {
475  case AVMEDIA_TYPE_VIDEO:
476  avio_w8(pb, FLV_TAG_TYPE_VIDEO);
477 
478  flags = enc->codec_tag;
479  if (flags == 0) {
480  av_log(s, AV_LOG_ERROR,
481  "Video codec '%s' is not compatible with FLV\n",
482  avcodec_get_name(enc->codec_id));
483  return AVERROR(EINVAL);
484  }
485 
486  flags |= pkt->flags & AV_PKT_FLAG_KEY ? FLV_FRAME_KEY : FLV_FRAME_INTER;
487  break;
488  case AVMEDIA_TYPE_AUDIO:
489  flags = get_audio_flags(s, enc);
490 
491  av_assert0(size);
492 
493  avio_w8(pb, FLV_TAG_TYPE_AUDIO);
494  break;
495  case AVMEDIA_TYPE_DATA:
496  avio_w8(pb, FLV_TAG_TYPE_META);
497  break;
498  default:
499  return AVERROR(EINVAL);
500  }
501 
502  if (enc->codec_id == AV_CODEC_ID_H264 || enc->codec_id == AV_CODEC_ID_MPEG4) {
503  /* check if extradata looks like mp4 formated */
504  if (enc->extradata_size > 0 && *(uint8_t*)enc->extradata != 1)
505  if ((ret = ff_avc_parse_nal_units_buf(pkt->data, &data, &size)) < 0)
506  return ret;
507  } else if (enc->codec_id == AV_CODEC_ID_AAC && pkt->size > 2 &&
508  (AV_RB16(pkt->data) & 0xfff0) == 0xfff0) {
509  if (!s->streams[pkt->stream_index]->nb_frames) {
510  av_log(s, AV_LOG_ERROR, "Malformed AAC bitstream detected: "
511  "use audio bitstream filter 'aac_adtstoasc' to fix it "
512  "('-bsf:a aac_adtstoasc' option with ffmpeg)\n");
513  return AVERROR_INVALIDDATA;
514  }
515  av_log(s, AV_LOG_WARNING, "aac bitstream error\n");
516  }
517 
518  if (flv->delay == AV_NOPTS_VALUE)
519  flv->delay = -pkt->dts;
520 
521  if (pkt->dts < -flv->delay) {
522  av_log(s, AV_LOG_WARNING,
523  "Packets are not in the proper order with respect to DTS\n");
524  return AVERROR(EINVAL);
525  }
526 
527  ts = pkt->dts + flv->delay; // add delay to force positive dts
528 
529  /* check Speex packet duration */
530  if (enc->codec_id == AV_CODEC_ID_SPEEX && ts - sc->last_ts > 160)
531  av_log(s, AV_LOG_WARNING, "Warning: Speex stream has more than "
532  "8 frames per packet. Adobe Flash "
533  "Player cannot handle this!\n");
534 
535  if (sc->last_ts < ts)
536  sc->last_ts = ts;
537 
538  avio_wb24(pb, size + flags_size);
539  avio_wb24(pb, ts);
540  avio_w8(pb, (ts >> 24) & 0x7F); // timestamps are 32 bits _signed_
541  avio_wb24(pb, flv->reserved);
542 
543  if (enc->codec_type == AVMEDIA_TYPE_DATA) {
544  int data_size;
545  int64_t metadata_size_pos = avio_tell(pb);
546  avio_w8(pb, AMF_DATA_TYPE_STRING);
547  put_amf_string(pb, "onTextData");
548  avio_w8(pb, AMF_DATA_TYPE_MIXEDARRAY);
549  avio_wb32(pb, 2);
550  put_amf_string(pb, "type");
551  avio_w8(pb, AMF_DATA_TYPE_STRING);
552  put_amf_string(pb, "Text");
553  put_amf_string(pb, "text");
554  avio_w8(pb, AMF_DATA_TYPE_STRING);
555  put_amf_string(pb, pkt->data);
556  put_amf_string(pb, "");
557  avio_w8(pb, AMF_END_OF_OBJECT);
558  /* write total size of tag */
559  data_size = avio_tell(pb) - metadata_size_pos;
560  avio_seek(pb, metadata_size_pos - 10, SEEK_SET);
561  avio_wb24(pb, data_size);
562  avio_seek(pb, data_size + 10 - 3, SEEK_CUR);
563  avio_wb32(pb, data_size + 11);
564  } else {
565  av_assert1(flags>=0);
566  avio_w8(pb,flags);
567  if (enc->codec_id == AV_CODEC_ID_VP6)
568  avio_w8(pb,0);
569  if (enc->codec_id == AV_CODEC_ID_VP6F || enc->codec_id == AV_CODEC_ID_VP6A) {
570  if (enc->extradata_size)
571  avio_w8(pb, enc->extradata[0]);
572  else
573  avio_w8(pb, ((FFALIGN(enc->width, 16) - enc->width) << 4) |
574  (FFALIGN(enc->height, 16) - enc->height));
575  } else if (enc->codec_id == AV_CODEC_ID_AAC)
576  avio_w8(pb, 1); // AAC raw
577  else if (enc->codec_id == AV_CODEC_ID_H264 || enc->codec_id == AV_CODEC_ID_MPEG4) {
578  avio_w8(pb, 1); // AVC NALU
579  avio_wb24(pb, pkt->pts - pkt->dts);
580  }
581 
582  avio_write(pb, data ? data : pkt->data, size);
583 
584  avio_wb32(pb, size + flags_size + 11); // previous tag size
585  flv->duration = FFMAX(flv->duration,
586  pkt->pts + flv->delay + pkt->duration);
587  }
588 
589  av_free(data);
590 
591  return pb->error;
592 }
593 
594 AVOutputFormat ff_flv_muxer = {
595  .name = "flv",
596  .long_name = NULL_IF_CONFIG_SMALL("FLV (Flash Video)"),
597  .mime_type = "video/x-flv",
598  .extensions = "flv",
599  .priv_data_size = sizeof(FLVContext),
600  .audio_codec = CONFIG_LIBMP3LAME ? AV_CODEC_ID_MP3 : AV_CODEC_ID_ADPCM_SWF,
601  .video_codec = AV_CODEC_ID_FLV1,
602  .write_header = flv_write_header,
603  .write_packet = flv_write_packet,
604  .write_trailer = flv_write_trailer,
605  .codec_tag = (const AVCodecTag* const []) {
606  flv_video_codec_ids, flv_audio_codec_ids, 0
607  },
608  .flags = AVFMT_GLOBALHEADER | AVFMT_VARIABLE_FPS |
609  AVFMT_TS_NONSTRICT,
610 };
Generated on Sat Mar 8 2014 19:20:58 for FFmpeg by   doxygen 1.8.2