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 "libavutil/mathematics.h"
27 #include "libavcodec/mpeg4audio.h"
28 #include "avio.h"
29 #include "avc.h"
30 #include "avformat.h"
31 #include "flv.h"
32 #include "internal.h"
33 #include "mux.h"
34 #include "libavutil/opt.h"
35 #include "libavcodec/put_bits.h"
36
37
38 static const AVCodecTag flv_video_codec_ids[] = {
39 { AV_CODEC_ID_FLV1, FLV_CODECID_H263 },
40 { AV_CODEC_ID_H263, FLV_CODECID_REALH263 },
41 { AV_CODEC_ID_MPEG4, FLV_CODECID_MPEG4 },
42 { AV_CODEC_ID_FLASHSV, FLV_CODECID_SCREEN },
43 { AV_CODEC_ID_FLASHSV2, FLV_CODECID_SCREEN2 },
44 { AV_CODEC_ID_VP6F, FLV_CODECID_VP6 },
45 { AV_CODEC_ID_VP6, FLV_CODECID_VP6 },
46 { AV_CODEC_ID_VP6A, FLV_CODECID_VP6A },
47 { AV_CODEC_ID_H264, FLV_CODECID_H264 },
48 { AV_CODEC_ID_NONE, 0 }
49 };
50
51 static const AVCodecTag flv_audio_codec_ids[] = {
52 { AV_CODEC_ID_MP3, FLV_CODECID_MP3 >> FLV_AUDIO_CODECID_OFFSET },
53 { AV_CODEC_ID_PCM_U8, FLV_CODECID_PCM >> FLV_AUDIO_CODECID_OFFSET },
54 { AV_CODEC_ID_PCM_S16BE, FLV_CODECID_PCM >> FLV_AUDIO_CODECID_OFFSET },
55 { AV_CODEC_ID_PCM_S16LE, FLV_CODECID_PCM_LE >> FLV_AUDIO_CODECID_OFFSET },
56 { AV_CODEC_ID_ADPCM_SWF, FLV_CODECID_ADPCM >> FLV_AUDIO_CODECID_OFFSET },
57 { AV_CODEC_ID_AAC, FLV_CODECID_AAC >> FLV_AUDIO_CODECID_OFFSET },
58 { AV_CODEC_ID_NELLYMOSER, FLV_CODECID_NELLYMOSER >> FLV_AUDIO_CODECID_OFFSET },
59 { AV_CODEC_ID_PCM_MULAW, FLV_CODECID_PCM_MULAW >> FLV_AUDIO_CODECID_OFFSET },
60 { AV_CODEC_ID_PCM_ALAW, FLV_CODECID_PCM_ALAW >> FLV_AUDIO_CODECID_OFFSET },
61 { AV_CODEC_ID_SPEEX, FLV_CODECID_SPEEX >> FLV_AUDIO_CODECID_OFFSET },
62 { AV_CODEC_ID_NONE, 0 }
63 };
64
65 typedef enum {
66 FLV_AAC_SEQ_HEADER_DETECT = (1 << 0),
67 FLV_NO_SEQUENCE_END = (1 << 1),
68 FLV_ADD_KEYFRAME_INDEX = (1 << 2),
69 FLV_NO_METADATA = (1 << 3),
70 FLV_NO_DURATION_FILESIZE = (1 << 4),
71 } FLVFlags;
72
73 typedef struct FLVFileposition {
74 int64_t keyframe_position;
75 double keyframe_timestamp;
76 struct FLVFileposition *next;
77 } FLVFileposition;
78
79 typedef struct FLVContext {
80 AVClass *av_class;
81 int reserved;
82 int64_t duration_offset;
83 int64_t filesize_offset;
84 int64_t duration;
85 int64_t delay; ///< first dts delay (needed for AVC & Speex)
86
87 int64_t datastart_offset;
88 int64_t datasize_offset;
89 int64_t datasize;
90 int64_t videosize_offset;
91 int64_t videosize;
92 int64_t audiosize_offset;
93 int64_t audiosize;
94
95 int64_t metadata_size_pos;
96 int64_t metadata_totalsize_pos;
97 int64_t metadata_totalsize;
98 int64_t keyframe_index_size;
99
100 int64_t lasttimestamp_offset;
101 double lasttimestamp;
102 int64_t lastkeyframetimestamp_offset;
103 double lastkeyframetimestamp;
104 int64_t lastkeyframelocation_offset;
105 int64_t lastkeyframelocation;
106
107 int acurframeindex;
108 int64_t keyframes_info_offset;
109
110 int64_t filepositions_count;
111 FLVFileposition *filepositions;
112 FLVFileposition *head_filepositions;
113
114 AVCodecParameters *audio_par;
115 AVCodecParameters *video_par;
116 double framerate;
117 AVCodecParameters *data_par;
118
119 int flags;
120 } FLVContext;
121
122 typedef struct FLVStreamContext {
123 int64_t last_ts; ///< last timestamp for each stream
124 } FLVStreamContext;
125
get_audio_flags(AVFormatContext *s, AVCodecParameters *par)126 static int get_audio_flags(AVFormatContext *s, AVCodecParameters *par)
127 {
128 int flags = (par->bits_per_coded_sample == 16) ? FLV_SAMPLESSIZE_16BIT
129 : FLV_SAMPLESSIZE_8BIT;
130
131 if (par->codec_id == AV_CODEC_ID_AAC) // specs force these parameters
132 return FLV_CODECID_AAC | FLV_SAMPLERATE_44100HZ |
133 FLV_SAMPLESSIZE_16BIT | FLV_STEREO;
134 else if (par->codec_id == AV_CODEC_ID_SPEEX) {
135 if (par->sample_rate != 16000) {
136 av_log(s, AV_LOG_ERROR,
137 "FLV only supports wideband (16kHz) Speex audio\n");
138 return AVERROR(EINVAL);
139 }
140 if (par->ch_layout.nb_channels != 1) {
141 av_log(s, AV_LOG_ERROR, "FLV only supports mono Speex audio\n");
142 return AVERROR(EINVAL);
143 }
144 return FLV_CODECID_SPEEX | FLV_SAMPLERATE_11025HZ | FLV_SAMPLESSIZE_16BIT;
145 } else {
146 switch (par->sample_rate) {
147 case 48000:
148 // 48khz mp3 is stored with 44k1 samplerate identifer
149 if (par->codec_id == AV_CODEC_ID_MP3) {
150 flags |= FLV_SAMPLERATE_44100HZ;
151 break;
152 } else {
153 goto error;
154 }
155 case 44100:
156 flags |= FLV_SAMPLERATE_44100HZ;
157 break;
158 case 22050:
159 flags |= FLV_SAMPLERATE_22050HZ;
160 break;
161 case 11025:
162 flags |= FLV_SAMPLERATE_11025HZ;
163 break;
164 case 16000: // nellymoser only
165 case 8000: // nellymoser only
166 case 5512: // not MP3
167 if (par->codec_id != AV_CODEC_ID_MP3) {
168 flags |= FLV_SAMPLERATE_SPECIAL;
169 break;
170 }
171 default:
172 error:
173 av_log(s, AV_LOG_ERROR,
174 "FLV does not support sample rate %d, "
175 "choose from (44100, 22050, 11025)\n", par->sample_rate);
176 return AVERROR(EINVAL);
177 }
178 }
179
180 if (par->ch_layout.nb_channels > 1)
181 flags |= FLV_STEREO;
182
183 switch (par->codec_id) {
184 case AV_CODEC_ID_MP3:
185 flags |= FLV_CODECID_MP3 | FLV_SAMPLESSIZE_16BIT;
186 break;
187 case AV_CODEC_ID_PCM_U8:
188 flags |= FLV_CODECID_PCM | FLV_SAMPLESSIZE_8BIT;
189 break;
190 case AV_CODEC_ID_PCM_S16BE:
191 flags |= FLV_CODECID_PCM | FLV_SAMPLESSIZE_16BIT;
192 break;
193 case AV_CODEC_ID_PCM_S16LE:
194 flags |= FLV_CODECID_PCM_LE | FLV_SAMPLESSIZE_16BIT;
195 break;
196 case AV_CODEC_ID_ADPCM_SWF:
197 flags |= FLV_CODECID_ADPCM | FLV_SAMPLESSIZE_16BIT;
198 break;
199 case AV_CODEC_ID_NELLYMOSER:
200 if (par->sample_rate == 8000)
201 flags |= FLV_CODECID_NELLYMOSER_8KHZ_MONO | FLV_SAMPLESSIZE_16BIT;
202 else if (par->sample_rate == 16000)
203 flags |= FLV_CODECID_NELLYMOSER_16KHZ_MONO | FLV_SAMPLESSIZE_16BIT;
204 else
205 flags |= FLV_CODECID_NELLYMOSER | FLV_SAMPLESSIZE_16BIT;
206 break;
207 case AV_CODEC_ID_PCM_MULAW:
208 flags = FLV_CODECID_PCM_MULAW | FLV_SAMPLERATE_SPECIAL | FLV_SAMPLESSIZE_16BIT;
209 break;
210 case AV_CODEC_ID_PCM_ALAW:
211 flags = FLV_CODECID_PCM_ALAW | FLV_SAMPLERATE_SPECIAL | FLV_SAMPLESSIZE_16BIT;
212 break;
213 case 0:
214 flags |= par->codec_tag << 4;
215 break;
216 default:
217 av_log(s, AV_LOG_ERROR, "Audio codec '%s' not compatible with FLV\n",
218 avcodec_get_name(par->codec_id));
219 return AVERROR(EINVAL);
220 }
221
222 return flags;
223 }
224
put_amf_string(AVIOContext *pb, const char *str)225 static void put_amf_string(AVIOContext *pb, const char *str)
226 {
227 size_t len = strlen(str);
228 avio_wb16(pb, len);
229 avio_write(pb, str, len);
230 }
231
232 // FLV timestamps are 32 bits signed, RTMP timestamps should be 32-bit unsigned
put_timestamp(AVIOContext *pb, int64_t ts)233 static void put_timestamp(AVIOContext *pb, int64_t ts) {
234 avio_wb24(pb, ts & 0xFFFFFF);
235 avio_w8(pb, (ts >> 24) & 0x7F);
236 }
237
put_avc_eos_tag(AVIOContext *pb, unsigned ts)238 static void put_avc_eos_tag(AVIOContext *pb, unsigned ts)
239 {
240 avio_w8(pb, FLV_TAG_TYPE_VIDEO);
241 avio_wb24(pb, 5); /* Tag Data Size */
242 put_timestamp(pb, ts);
243 avio_wb24(pb, 0); /* StreamId = 0 */
244 avio_w8(pb, 23); /* ub[4] FrameType = 1, ub[4] CodecId = 7 */
245 avio_w8(pb, 2); /* AVC end of sequence */
246 avio_wb24(pb, 0); /* Always 0 for AVC EOS. */
247 avio_wb32(pb, 16); /* Size of FLV tag */
248 }
249
put_amf_double(AVIOContext *pb, double d)250 static void put_amf_double(AVIOContext *pb, double d)
251 {
252 avio_w8(pb, AMF_DATA_TYPE_NUMBER);
253 avio_wb64(pb, av_double2int(d));
254 }
255
put_amf_byte(AVIOContext *pb, unsigned char abyte)256 static void put_amf_byte(AVIOContext *pb, unsigned char abyte)
257 {
258 avio_w8(pb, abyte);
259 }
260
put_amf_dword_array(AVIOContext *pb, uint32_t dw)261 static void put_amf_dword_array(AVIOContext *pb, uint32_t dw)
262 {
263 avio_w8(pb, AMF_DATA_TYPE_ARRAY);
264 avio_wb32(pb, dw);
265 }
266
put_amf_bool(AVIOContext *pb, int b)267 static void put_amf_bool(AVIOContext *pb, int b)
268 {
269 avio_w8(pb, AMF_DATA_TYPE_BOOL);
270 avio_w8(pb, !!b);
271 }
272
write_metadata(AVFormatContext *s, unsigned int ts)273 static void write_metadata(AVFormatContext *s, unsigned int ts)
274 {
275 AVIOContext *pb = s->pb;
276 FLVContext *flv = s->priv_data;
277 int write_duration_filesize = !(flv->flags & FLV_NO_DURATION_FILESIZE);
278 int metadata_count = 0;
279 int64_t metadata_count_pos;
280 AVDictionaryEntry *tag = NULL;
281
282 /* write meta_tag */
283 avio_w8(pb, FLV_TAG_TYPE_META); // tag type META
284 flv->metadata_size_pos = avio_tell(pb);
285 avio_wb24(pb, 0); // size of data part (sum of all parts below)
286 put_timestamp(pb, ts); // timestamp
287 avio_wb24(pb, 0); // reserved
288
289 /* now data of data_size size */
290
291 /* first event name as a string */
292 avio_w8(pb, AMF_DATA_TYPE_STRING);
293 put_amf_string(pb, "onMetaData"); // 12 bytes
294
295 /* mixed array (hash) with size and string/type/data tuples */
296 avio_w8(pb, AMF_DATA_TYPE_MIXEDARRAY);
297 metadata_count_pos = avio_tell(pb);
298 metadata_count = 4 * !!flv->video_par +
299 5 * !!flv->audio_par +
300 1 * !!flv->data_par;
301 if (write_duration_filesize) {
302 metadata_count += 2; // +2 for duration and file size
303 }
304 avio_wb32(pb, metadata_count);
305
306 if (write_duration_filesize) {
307 put_amf_string(pb, "duration");
308 flv->duration_offset = avio_tell(pb);
309 // fill in the guessed duration, it'll be corrected later if incorrect
310 put_amf_double(pb, s->duration / AV_TIME_BASE);
311 }
312
313 if (flv->video_par) {
314 put_amf_string(pb, "width");
315 put_amf_double(pb, flv->video_par->width);
316
317 put_amf_string(pb, "height");
318 put_amf_double(pb, flv->video_par->height);
319
320 put_amf_string(pb, "videodatarate");
321 put_amf_double(pb, flv->video_par->bit_rate / 1024.0);
322
323 if (flv->framerate != 0.0) {
324 put_amf_string(pb, "framerate");
325 put_amf_double(pb, flv->framerate);
326 metadata_count++;
327 }
328
329 put_amf_string(pb, "videocodecid");
330 put_amf_double(pb, flv->video_par->codec_tag);
331 }
332
333 if (flv->audio_par) {
334 put_amf_string(pb, "audiodatarate");
335 put_amf_double(pb, flv->audio_par->bit_rate / 1024.0);
336
337 put_amf_string(pb, "audiosamplerate");
338 put_amf_double(pb, flv->audio_par->sample_rate);
339
340 put_amf_string(pb, "audiosamplesize");
341 put_amf_double(pb, flv->audio_par->codec_id == AV_CODEC_ID_PCM_U8 ? 8 : 16);
342
343 put_amf_string(pb, "stereo");
344 put_amf_bool(pb, flv->audio_par->ch_layout.nb_channels == 2);
345
346 put_amf_string(pb, "audiocodecid");
347 put_amf_double(pb, flv->audio_par->codec_tag);
348 }
349
350 if (flv->data_par) {
351 put_amf_string(pb, "datastream");
352 put_amf_double(pb, 0.0);
353 }
354
355 ff_standardize_creation_time(s);
356 while ((tag = av_dict_get(s->metadata, "", tag, AV_DICT_IGNORE_SUFFIX))) {
357 if( !strcmp(tag->key, "width")
358 ||!strcmp(tag->key, "height")
359 ||!strcmp(tag->key, "videodatarate")
360 ||!strcmp(tag->key, "framerate")
361 ||!strcmp(tag->key, "videocodecid")
362 ||!strcmp(tag->key, "audiodatarate")
363 ||!strcmp(tag->key, "audiosamplerate")
364 ||!strcmp(tag->key, "audiosamplesize")
365 ||!strcmp(tag->key, "stereo")
366 ||!strcmp(tag->key, "audiocodecid")
367 ||!strcmp(tag->key, "duration")
368 ||!strcmp(tag->key, "onMetaData")
369 ||!strcmp(tag->key, "datasize")
370 ||!strcmp(tag->key, "lasttimestamp")
371 ||!strcmp(tag->key, "totalframes")
372 ||!strcmp(tag->key, "hasAudio")
373 ||!strcmp(tag->key, "hasVideo")
374 ||!strcmp(tag->key, "hasCuePoints")
375 ||!strcmp(tag->key, "hasMetadata")
376 ||!strcmp(tag->key, "hasKeyframes")
377 ){
378 av_log(s, AV_LOG_DEBUG, "Ignoring metadata for %s\n", tag->key);
379 continue;
380 }
381 put_amf_string(pb, tag->key);
382 avio_w8(pb, AMF_DATA_TYPE_STRING);
383 put_amf_string(pb, tag->value);
384 metadata_count++;
385 }
386
387 if (write_duration_filesize) {
388 put_amf_string(pb, "filesize");
389 flv->filesize_offset = avio_tell(pb);
390 put_amf_double(pb, 0); // delayed write
391 }
392
393 if (flv->flags & FLV_ADD_KEYFRAME_INDEX) {
394 flv->acurframeindex = 0;
395 flv->keyframe_index_size = 0;
396
397 put_amf_string(pb, "hasVideo");
398 put_amf_bool(pb, !!flv->video_par);
399 metadata_count++;
400
401 put_amf_string(pb, "hasKeyframes");
402 put_amf_bool(pb, 1);
403 metadata_count++;
404
405 put_amf_string(pb, "hasAudio");
406 put_amf_bool(pb, !!flv->audio_par);
407 metadata_count++;
408
409 put_amf_string(pb, "hasMetadata");
410 put_amf_bool(pb, 1);
411 metadata_count++;
412
413 put_amf_string(pb, "canSeekToEnd");
414 put_amf_bool(pb, 1);
415 metadata_count++;
416
417 put_amf_string(pb, "datasize");
418 flv->datasize_offset = avio_tell(pb);
419 flv->datasize = 0;
420 put_amf_double(pb, flv->datasize);
421 metadata_count++;
422
423 put_amf_string(pb, "videosize");
424 flv->videosize_offset = avio_tell(pb);
425 flv->videosize = 0;
426 put_amf_double(pb, flv->videosize);
427 metadata_count++;
428
429 put_amf_string(pb, "audiosize");
430 flv->audiosize_offset = avio_tell(pb);
431 flv->audiosize = 0;
432 put_amf_double(pb, flv->audiosize);
433 metadata_count++;
434
435 put_amf_string(pb, "lasttimestamp");
436 flv->lasttimestamp_offset = avio_tell(pb);
437 flv->lasttimestamp = 0;
438 put_amf_double(pb, 0);
439 metadata_count++;
440
441 put_amf_string(pb, "lastkeyframetimestamp");
442 flv->lastkeyframetimestamp_offset = avio_tell(pb);
443 flv->lastkeyframetimestamp = 0;
444 put_amf_double(pb, 0);
445 metadata_count++;
446
447 put_amf_string(pb, "lastkeyframelocation");
448 flv->lastkeyframelocation_offset = avio_tell(pb);
449 flv->lastkeyframelocation = 0;
450 put_amf_double(pb, 0);
451 metadata_count++;
452
453 put_amf_string(pb, "keyframes");
454 put_amf_byte(pb, AMF_DATA_TYPE_OBJECT);
455 metadata_count++;
456
457 flv->keyframes_info_offset = avio_tell(pb);
458 }
459
460 put_amf_string(pb, "");
461 avio_w8(pb, AMF_END_OF_OBJECT);
462
463 /* write total size of tag */
464 flv->metadata_totalsize = avio_tell(pb) - flv->metadata_size_pos - 10;
465
466 avio_seek(pb, metadata_count_pos, SEEK_SET);
467 avio_wb32(pb, metadata_count);
468
469 avio_seek(pb, flv->metadata_size_pos, SEEK_SET);
470 avio_wb24(pb, flv->metadata_totalsize);
471 avio_skip(pb, flv->metadata_totalsize + 10 - 3);
472 flv->metadata_totalsize_pos = avio_tell(pb);
473 avio_wb32(pb, flv->metadata_totalsize + 11);
474 }
475
unsupported_codec(AVFormatContext *s, const char* type, int codec_id)476 static int unsupported_codec(AVFormatContext *s,
477 const char* type, int codec_id)
478 {
479 const AVCodecDescriptor *desc = avcodec_descriptor_get(codec_id);
480 av_log(s, AV_LOG_ERROR,
481 "%s codec %s not compatible with flv\n",
482 type,
483 desc ? desc->name : "unknown");
484 return AVERROR(ENOSYS);
485 }
486
flv_write_codec_header(AVFormatContext* s, AVCodecParameters* par, int64_t ts)487 static void flv_write_codec_header(AVFormatContext* s, AVCodecParameters* par, int64_t ts) {
488 int64_t data_size;
489 AVIOContext *pb = s->pb;
490 FLVContext *flv = s->priv_data;
491
492 if (par->codec_id == AV_CODEC_ID_AAC || par->codec_id == AV_CODEC_ID_H264
493 || par->codec_id == AV_CODEC_ID_MPEG4) {
494 int64_t pos;
495 avio_w8(pb,
496 par->codec_type == AVMEDIA_TYPE_VIDEO ?
497 FLV_TAG_TYPE_VIDEO : FLV_TAG_TYPE_AUDIO);
498 avio_wb24(pb, 0); // size patched later
499 put_timestamp(pb, ts);
500 avio_wb24(pb, 0); // streamid
501 pos = avio_tell(pb);
502 if (par->codec_id == AV_CODEC_ID_AAC) {
503 avio_w8(pb, get_audio_flags(s, par));
504 avio_w8(pb, 0); // AAC sequence header
505
506 if (!par->extradata_size && (flv->flags & FLV_AAC_SEQ_HEADER_DETECT)) {
507 PutBitContext pbc;
508 int samplerate_index;
509 int channels = flv->audio_par->ch_layout.nb_channels
510 - (flv->audio_par->ch_layout.nb_channels == 8 ? 1 : 0);
511 uint8_t data[2];
512
513 for (samplerate_index = 0; samplerate_index < 16;
514 samplerate_index++)
515 if (flv->audio_par->sample_rate
516 == ff_mpeg4audio_sample_rates[samplerate_index])
517 break;
518
519 init_put_bits(&pbc, data, sizeof(data));
520 put_bits(&pbc, 5, flv->audio_par->profile + 1); //profile
521 put_bits(&pbc, 4, samplerate_index); //sample rate index
522 put_bits(&pbc, 4, channels);
523 put_bits(&pbc, 1, 0); //frame length - 1024 samples
524 put_bits(&pbc, 1, 0); //does not depend on core coder
525 put_bits(&pbc, 1, 0); //is not extension
526 flush_put_bits(&pbc);
527
528 avio_w8(pb, data[0]);
529 avio_w8(pb, data[1]);
530
531 av_log(s, AV_LOG_WARNING, "AAC sequence header: %02x %02x.\n",
532 data[0], data[1]);
533 }
534 avio_write(pb, par->extradata, par->extradata_size);
535 } else {
536 avio_w8(pb, par->codec_tag | FLV_FRAME_KEY); // flags
537 avio_w8(pb, 0); // AVC sequence header
538 avio_wb24(pb, 0); // composition time
539 ff_isom_write_avcc(pb, par->extradata, par->extradata_size);
540 }
541 data_size = avio_tell(pb) - pos;
542 avio_seek(pb, -data_size - 10, SEEK_CUR);
543 avio_wb24(pb, data_size);
544 avio_skip(pb, data_size + 10 - 3);
545 avio_wb32(pb, data_size + 11); // previous tag size
546 }
547 }
548
flv_append_keyframe_info(AVFormatContext *s, FLVContext *flv, double ts, int64_t pos)549 static int flv_append_keyframe_info(AVFormatContext *s, FLVContext *flv, double ts, int64_t pos)
550 {
551 FLVFileposition *position = av_malloc(sizeof(FLVFileposition));
552
553 if (!position) {
554 av_log(s, AV_LOG_WARNING, "no mem for add keyframe index!\n");
555 return AVERROR(ENOMEM);
556 }
557
558 position->keyframe_timestamp = ts;
559 position->keyframe_position = pos;
560
561 if (!flv->filepositions_count) {
562 flv->filepositions = position;
563 flv->head_filepositions = flv->filepositions;
564 position->next = NULL;
565 } else {
566 flv->filepositions->next = position;
567 position->next = NULL;
568 flv->filepositions = flv->filepositions->next;
569 }
570
571 flv->filepositions_count++;
572
573 return 0;
574 }
575
shift_data(AVFormatContext *s)576 static int shift_data(AVFormatContext *s)
577 {
578 int ret;
579 int64_t metadata_size = 0;
580 FLVContext *flv = s->priv_data;
581
582 metadata_size = flv->filepositions_count * 9 * 2 + 10; /* filepositions and times value */
583 metadata_size += 2 + 13; /* filepositions String */
584 metadata_size += 2 + 5; /* times String */
585 metadata_size += 3; /* Object end */
586
587 flv->keyframe_index_size = metadata_size;
588
589 if (metadata_size < 0)
590 return metadata_size;
591
592 ret = ff_format_shift_data(s, flv->keyframes_info_offset, metadata_size);
593 if (ret < 0)
594 return ret;
595
596 avio_seek(s->pb, flv->metadata_size_pos, SEEK_SET);
597 avio_wb24(s->pb, flv->metadata_totalsize + metadata_size);
598
599 avio_seek(s->pb, flv->metadata_totalsize_pos + metadata_size, SEEK_SET);
600 avio_wb32(s->pb, flv->metadata_totalsize + 11 + metadata_size);
601
602 return 0;
603 }
604
flv_init(struct AVFormatContext *s)605 static int flv_init(struct AVFormatContext *s)
606 {
607 int i;
608 FLVContext *flv = s->priv_data;
609
610 for (i = 0; i < s->nb_streams; i++) {
611 AVCodecParameters *par = s->streams[i]->codecpar;
612 FLVStreamContext *sc;
613 switch (par->codec_type) {
614 case AVMEDIA_TYPE_VIDEO:
615 if (s->streams[i]->avg_frame_rate.den &&
616 s->streams[i]->avg_frame_rate.num) {
617 flv->framerate = av_q2d(s->streams[i]->avg_frame_rate);
618 }
619 if (flv->video_par) {
620 av_log(s, AV_LOG_ERROR,
621 "at most one video stream is supported in flv\n");
622 return AVERROR(EINVAL);
623 }
624 flv->video_par = par;
625 if (!ff_codec_get_tag(flv_video_codec_ids, par->codec_id))
626 return unsupported_codec(s, "Video", par->codec_id);
627
628 if (par->codec_id == AV_CODEC_ID_MPEG4 ||
629 par->codec_id == AV_CODEC_ID_H263) {
630 int error = s->strict_std_compliance > FF_COMPLIANCE_UNOFFICIAL;
631 av_log(s, error ? AV_LOG_ERROR : AV_LOG_WARNING,
632 "Codec %s is not supported in the official FLV specification,\n", avcodec_get_name(par->codec_id));
633
634 if (error) {
635 av_log(s, AV_LOG_ERROR,
636 "use vstrict=-1 / -strict -1 to use it anyway.\n");
637 return AVERROR(EINVAL);
638 }
639 } else if (par->codec_id == AV_CODEC_ID_VP6) {
640 av_log(s, AV_LOG_WARNING,
641 "Muxing VP6 in flv will produce flipped video on playback.\n");
642 }
643 break;
644 case AVMEDIA_TYPE_AUDIO:
645 if (flv->audio_par) {
646 av_log(s, AV_LOG_ERROR,
647 "at most one audio stream is supported in flv\n");
648 return AVERROR(EINVAL);
649 }
650 flv->audio_par = par;
651 if (get_audio_flags(s, par) < 0)
652 return unsupported_codec(s, "Audio", par->codec_id);
653 if (par->codec_id == AV_CODEC_ID_PCM_S16BE)
654 av_log(s, AV_LOG_WARNING,
655 "16-bit big-endian audio in flv is valid but most likely unplayable (hardware dependent); use s16le\n");
656 break;
657 case AVMEDIA_TYPE_DATA:
658 if (par->codec_id != AV_CODEC_ID_TEXT && par->codec_id != AV_CODEC_ID_NONE)
659 return unsupported_codec(s, "Data", par->codec_id);
660 flv->data_par = par;
661 break;
662 case AVMEDIA_TYPE_SUBTITLE:
663 if (par->codec_id != AV_CODEC_ID_TEXT) {
664 av_log(s, AV_LOG_ERROR, "Subtitle codec '%s' for stream %d is not compatible with FLV\n",
665 avcodec_get_name(par->codec_id), i);
666 return AVERROR_INVALIDDATA;
667 }
668 flv->data_par = par;
669 break;
670 default:
671 av_log(s, AV_LOG_ERROR, "Codec type '%s' for stream %d is not compatible with FLV\n",
672 av_get_media_type_string(par->codec_type), i);
673 return AVERROR(EINVAL);
674 }
675 avpriv_set_pts_info(s->streams[i], 32, 1, 1000); /* 32 bit pts in ms */
676
677 sc = av_mallocz(sizeof(FLVStreamContext));
678 if (!sc)
679 return AVERROR(ENOMEM);
680 s->streams[i]->priv_data = sc;
681 sc->last_ts = -1;
682 }
683
684 flv->delay = AV_NOPTS_VALUE;
685
686 return 0;
687 }
688
flv_write_header(AVFormatContext *s)689 static int flv_write_header(AVFormatContext *s)
690 {
691 int i;
692 AVIOContext *pb = s->pb;
693 FLVContext *flv = s->priv_data;
694
695 avio_write(pb, "FLV", 3);
696 avio_w8(pb, 1);
697 avio_w8(pb, FLV_HEADER_FLAG_HASAUDIO * !!flv->audio_par +
698 FLV_HEADER_FLAG_HASVIDEO * !!flv->video_par);
699 avio_wb32(pb, 9);
700 avio_wb32(pb, 0);
701
702 for (i = 0; i < s->nb_streams; i++)
703 if (s->streams[i]->codecpar->codec_tag == 5) {
704 avio_w8(pb, 8); // message type
705 avio_wb24(pb, 0); // include flags
706 avio_wb24(pb, 0); // time stamp
707 avio_wb32(pb, 0); // reserved
708 avio_wb32(pb, 11); // size
709 flv->reserved = 5;
710 }
711
712 if (flv->flags & FLV_NO_METADATA) {
713 pb->seekable = 0;
714 } else {
715 write_metadata(s, 0);
716 }
717
718 for (i = 0; i < s->nb_streams; i++) {
719 flv_write_codec_header(s, s->streams[i]->codecpar, 0);
720 }
721
722 flv->datastart_offset = avio_tell(pb);
723 return 0;
724 }
725
flv_write_trailer(AVFormatContext *s)726 static int flv_write_trailer(AVFormatContext *s)
727 {
728 int64_t file_size;
729 AVIOContext *pb = s->pb;
730 FLVContext *flv = s->priv_data;
731 int build_keyframes_idx = flv->flags & FLV_ADD_KEYFRAME_INDEX;
732 int i, res;
733 int64_t cur_pos = avio_tell(s->pb);
734
735 if (build_keyframes_idx) {
736 const FLVFileposition *newflv_posinfo;
737
738 avio_seek(pb, flv->videosize_offset, SEEK_SET);
739 put_amf_double(pb, flv->videosize);
740
741 avio_seek(pb, flv->audiosize_offset, SEEK_SET);
742 put_amf_double(pb, flv->audiosize);
743
744 avio_seek(pb, flv->lasttimestamp_offset, SEEK_SET);
745 put_amf_double(pb, flv->lasttimestamp);
746
747 avio_seek(pb, flv->lastkeyframetimestamp_offset, SEEK_SET);
748 put_amf_double(pb, flv->lastkeyframetimestamp);
749
750 avio_seek(pb, flv->lastkeyframelocation_offset, SEEK_SET);
751 put_amf_double(pb, flv->lastkeyframelocation + flv->keyframe_index_size);
752 avio_seek(pb, cur_pos, SEEK_SET);
753
754 res = shift_data(s);
755 if (res < 0) {
756 goto end;
757 }
758 avio_seek(pb, flv->keyframes_info_offset, SEEK_SET);
759 put_amf_string(pb, "filepositions");
760 put_amf_dword_array(pb, flv->filepositions_count);
761 for (newflv_posinfo = flv->head_filepositions; newflv_posinfo; newflv_posinfo = newflv_posinfo->next) {
762 put_amf_double(pb, newflv_posinfo->keyframe_position + flv->keyframe_index_size);
763 }
764
765 put_amf_string(pb, "times");
766 put_amf_dword_array(pb, flv->filepositions_count);
767 for (newflv_posinfo = flv->head_filepositions; newflv_posinfo; newflv_posinfo = newflv_posinfo->next) {
768 put_amf_double(pb, newflv_posinfo->keyframe_timestamp);
769 }
770
771 put_amf_string(pb, "");
772 avio_w8(pb, AMF_END_OF_OBJECT);
773
774 avio_seek(pb, cur_pos + flv->keyframe_index_size, SEEK_SET);
775 }
776
777 end:
778 if (flv->flags & FLV_NO_SEQUENCE_END) {
779 av_log(s, AV_LOG_DEBUG, "FLV no sequence end mode open\n");
780 } else {
781 /* Add EOS tag */
782 for (i = 0; i < s->nb_streams; i++) {
783 AVCodecParameters *par = s->streams[i]->codecpar;
784 FLVStreamContext *sc = s->streams[i]->priv_data;
785 if (par->codec_type == AVMEDIA_TYPE_VIDEO &&
786 (par->codec_id == AV_CODEC_ID_H264 || par->codec_id == AV_CODEC_ID_MPEG4))
787 put_avc_eos_tag(pb, sc->last_ts);
788 }
789 }
790
791 file_size = avio_tell(pb);
792
793 if (build_keyframes_idx) {
794 flv->datasize = file_size - flv->datastart_offset;
795 avio_seek(pb, flv->datasize_offset, SEEK_SET);
796 put_amf_double(pb, flv->datasize);
797 }
798 if (!(flv->flags & FLV_NO_METADATA)) {
799 if (!(flv->flags & FLV_NO_DURATION_FILESIZE)) {
800 /* update information */
801 if (avio_seek(pb, flv->duration_offset, SEEK_SET) < 0) {
802 av_log(s, AV_LOG_WARNING, "Failed to update header with correct duration.\n");
803 } else {
804 put_amf_double(pb, flv->duration / (double)1000);
805 }
806 if (avio_seek(pb, flv->filesize_offset, SEEK_SET) < 0) {
807 av_log(s, AV_LOG_WARNING, "Failed to update header with correct filesize.\n");
808 } else {
809 put_amf_double(pb, file_size);
810 }
811 }
812 }
813
814 return 0;
815 }
816
flv_write_packet(AVFormatContext *s, AVPacket *pkt)817 static int flv_write_packet(AVFormatContext *s, AVPacket *pkt)
818 {
819 AVIOContext *pb = s->pb;
820 AVCodecParameters *par = s->streams[pkt->stream_index]->codecpar;
821 FLVContext *flv = s->priv_data;
822 FLVStreamContext *sc = s->streams[pkt->stream_index]->priv_data;
823 unsigned ts;
824 int size = pkt->size;
825 uint8_t *data = NULL;
826 int flags = -1, flags_size, ret = 0;
827 int64_t cur_offset = avio_tell(pb);
828
829 if (par->codec_type == AVMEDIA_TYPE_AUDIO && !pkt->size) {
830 av_log(s, AV_LOG_WARNING, "Empty audio Packet\n");
831 return AVERROR(EINVAL);
832 }
833
834 if (par->codec_id == AV_CODEC_ID_VP6F || par->codec_id == AV_CODEC_ID_VP6A ||
835 par->codec_id == AV_CODEC_ID_VP6 || par->codec_id == AV_CODEC_ID_AAC)
836 flags_size = 2;
837 else if (par->codec_id == AV_CODEC_ID_H264 || par->codec_id == AV_CODEC_ID_MPEG4)
838 flags_size = 5;
839 else
840 flags_size = 1;
841
842 if (par->codec_id == AV_CODEC_ID_AAC || par->codec_id == AV_CODEC_ID_H264
843 || par->codec_id == AV_CODEC_ID_MPEG4) {
844 size_t side_size;
845 uint8_t *side = av_packet_get_side_data(pkt, AV_PKT_DATA_NEW_EXTRADATA, &side_size);
846 if (side && side_size > 0 && (side_size != par->extradata_size || memcmp(side, par->extradata, side_size))) {
847 ret = ff_alloc_extradata(par, side_size);
848 if (ret < 0)
849 return ret;
850 memcpy(par->extradata, side, side_size);
851 flv_write_codec_header(s, par, pkt->dts);
852 }
853 }
854
855 if (flv->delay == AV_NOPTS_VALUE)
856 flv->delay = -pkt->dts;
857
858 if (pkt->dts < -flv->delay) {
859 av_log(s, AV_LOG_WARNING,
860 "Packets are not in the proper order with respect to DTS\n");
861 return AVERROR(EINVAL);
862 }
863 if (par->codec_id == AV_CODEC_ID_H264 || par->codec_id == AV_CODEC_ID_MPEG4) {
864 if (pkt->pts == AV_NOPTS_VALUE) {
865 av_log(s, AV_LOG_ERROR, "Packet is missing PTS\n");
866 return AVERROR(EINVAL);
867 }
868 }
869
870 ts = pkt->dts;
871
872 if (s->event_flags & AVSTREAM_EVENT_FLAG_METADATA_UPDATED) {
873 write_metadata(s, ts);
874 s->event_flags &= ~AVSTREAM_EVENT_FLAG_METADATA_UPDATED;
875 }
876
877 avio_write_marker(pb, av_rescale(ts, AV_TIME_BASE, 1000),
878 pkt->flags & AV_PKT_FLAG_KEY && (flv->video_par ? par->codec_type == AVMEDIA_TYPE_VIDEO : 1) ? AVIO_DATA_MARKER_SYNC_POINT : AVIO_DATA_MARKER_BOUNDARY_POINT);
879
880 switch (par->codec_type) {
881 case AVMEDIA_TYPE_VIDEO:
882 avio_w8(pb, FLV_TAG_TYPE_VIDEO);
883
884 flags = ff_codec_get_tag(flv_video_codec_ids, par->codec_id);
885
886 flags |= pkt->flags & AV_PKT_FLAG_KEY ? FLV_FRAME_KEY : FLV_FRAME_INTER;
887 break;
888 case AVMEDIA_TYPE_AUDIO:
889 flags = get_audio_flags(s, par);
890
891 av_assert0(size);
892
893 avio_w8(pb, FLV_TAG_TYPE_AUDIO);
894 break;
895 case AVMEDIA_TYPE_SUBTITLE:
896 case AVMEDIA_TYPE_DATA:
897 avio_w8(pb, FLV_TAG_TYPE_META);
898 break;
899 default:
900 return AVERROR(EINVAL);
901 }
902
903 if (par->codec_id == AV_CODEC_ID_H264 || par->codec_id == AV_CODEC_ID_MPEG4) {
904 /* check if extradata looks like mp4 formatted */
905 if (par->extradata_size > 0 && *(uint8_t*)par->extradata != 1)
906 if ((ret = ff_avc_parse_nal_units_buf(pkt->data, &data, &size)) < 0)
907 return ret;
908 } else if (par->codec_id == AV_CODEC_ID_AAC && pkt->size > 2 &&
909 (AV_RB16(pkt->data) & 0xfff0) == 0xfff0) {
910 if (!s->streams[pkt->stream_index]->nb_frames) {
911 av_log(s, AV_LOG_ERROR, "Malformed AAC bitstream detected: "
912 "use the audio bitstream filter 'aac_adtstoasc' to fix it "
913 "('-bsf:a aac_adtstoasc' option with ffmpeg)\n");
914 return AVERROR_INVALIDDATA;
915 }
916 av_log(s, AV_LOG_WARNING, "aac bitstream error\n");
917 }
918
919 /* check Speex packet duration */
920 if (par->codec_id == AV_CODEC_ID_SPEEX && ts - sc->last_ts > 160)
921 av_log(s, AV_LOG_WARNING, "Warning: Speex stream has more than "
922 "8 frames per packet. Adobe Flash "
923 "Player cannot handle this!\n");
924
925 if (sc->last_ts < ts)
926 sc->last_ts = ts;
927
928 if (size + flags_size >= 1<<24) {
929 av_log(s, AV_LOG_ERROR, "Too large packet with size %u >= %u\n",
930 size + flags_size, 1<<24);
931 ret = AVERROR(EINVAL);
932 goto fail;
933 }
934
935 avio_wb24(pb, size + flags_size);
936 put_timestamp(pb, ts);
937 avio_wb24(pb, flv->reserved);
938
939 if (par->codec_type == AVMEDIA_TYPE_DATA ||
940 par->codec_type == AVMEDIA_TYPE_SUBTITLE ) {
941 int data_size;
942 int64_t metadata_size_pos = avio_tell(pb);
943 if (par->codec_id == AV_CODEC_ID_TEXT) {
944 // legacy FFmpeg magic?
945 avio_w8(pb, AMF_DATA_TYPE_STRING);
946 put_amf_string(pb, "onTextData");
947 avio_w8(pb, AMF_DATA_TYPE_MIXEDARRAY);
948 avio_wb32(pb, 2);
949 put_amf_string(pb, "type");
950 avio_w8(pb, AMF_DATA_TYPE_STRING);
951 put_amf_string(pb, "Text");
952 put_amf_string(pb, "text");
953 avio_w8(pb, AMF_DATA_TYPE_STRING);
954 put_amf_string(pb, pkt->data);
955 put_amf_string(pb, "");
956 avio_w8(pb, AMF_END_OF_OBJECT);
957 } else {
958 // just pass the metadata through
959 avio_write(pb, data ? data : pkt->data, size);
960 }
961 /* write total size of tag */
962 data_size = avio_tell(pb) - metadata_size_pos;
963 avio_seek(pb, metadata_size_pos - 10, SEEK_SET);
964 avio_wb24(pb, data_size);
965 avio_seek(pb, data_size + 10 - 3, SEEK_CUR);
966 avio_wb32(pb, data_size + 11);
967 } else {
968 av_assert1(flags>=0);
969 avio_w8(pb,flags);
970 if (par->codec_id == AV_CODEC_ID_VP6)
971 avio_w8(pb,0);
972 if (par->codec_id == AV_CODEC_ID_VP6F || par->codec_id == AV_CODEC_ID_VP6A) {
973 if (par->extradata_size)
974 avio_w8(pb, par->extradata[0]);
975 else
976 avio_w8(pb, ((FFALIGN(par->width, 16) - par->width) << 4) |
977 (FFALIGN(par->height, 16) - par->height));
978 } else if (par->codec_id == AV_CODEC_ID_AAC)
979 avio_w8(pb, 1); // AAC raw
980 else if (par->codec_id == AV_CODEC_ID_H264 || par->codec_id == AV_CODEC_ID_MPEG4) {
981 avio_w8(pb, 1); // AVC NALU
982 avio_wb24(pb, pkt->pts - pkt->dts);
983 }
984
985 avio_write(pb, data ? data : pkt->data, size);
986
987 avio_wb32(pb, size + flags_size + 11); // previous tag size
988 flv->duration = FFMAX(flv->duration,
989 pkt->pts + flv->delay + pkt->duration);
990 }
991
992 if (flv->flags & FLV_ADD_KEYFRAME_INDEX) {
993 switch (par->codec_type) {
994 case AVMEDIA_TYPE_VIDEO:
995 flv->videosize += (avio_tell(pb) - cur_offset);
996 flv->lasttimestamp = flv->acurframeindex / flv->framerate;
997 flv->acurframeindex++;
998 if (pkt->flags & AV_PKT_FLAG_KEY) {
999 double ts = flv->lasttimestamp;
1000 int64_t pos = cur_offset;
1001
1002 flv->lastkeyframetimestamp = ts;
1003 flv->lastkeyframelocation = pos;
1004 ret = flv_append_keyframe_info(s, flv, ts, pos);
1005 if (ret < 0)
1006 goto fail;
1007 }
1008 break;
1009
1010 case AVMEDIA_TYPE_AUDIO:
1011 flv->audiosize += (avio_tell(pb) - cur_offset);
1012 break;
1013
1014 default:
1015 av_log(s, AV_LOG_WARNING, "par->codec_type is type = [%d]\n", par->codec_type);
1016 break;
1017 }
1018 }
1019 fail:
1020 av_free(data);
1021
1022 return ret;
1023 }
1024
flv_check_bitstream(AVFormatContext *s, AVStream *st, const AVPacket *pkt)1025 static int flv_check_bitstream(AVFormatContext *s, AVStream *st,
1026 const AVPacket *pkt)
1027 {
1028 int ret = 1;
1029
1030 if (st->codecpar->codec_id == AV_CODEC_ID_AAC) {
1031 if (pkt->size > 2 && (AV_RB16(pkt->data) & 0xfff0) == 0xfff0)
1032 ret = ff_stream_add_bitstream_filter(st, "aac_adtstoasc", NULL);
1033 }
1034 return ret;
1035 }
1036
flv_deinit(AVFormatContext *s)1037 static void flv_deinit(AVFormatContext *s)
1038 {
1039 FLVContext *flv = s->priv_data;
1040 FLVFileposition *filepos = flv->head_filepositions;
1041
1042 while (filepos) {
1043 FLVFileposition *next = filepos->next;
1044 av_free(filepos);
1045 filepos = next;
1046 }
1047 flv->filepositions = flv->head_filepositions = NULL;
1048 flv->filepositions_count = 0;
1049 }
1050
1051 static const AVOption options[] = {
1052 { "flvflags", "FLV muxer flags", offsetof(FLVContext, flags), AV_OPT_TYPE_FLAGS, {.i64 = 0}, INT_MIN, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM, "flvflags" },
1053 { "aac_seq_header_detect", "Put AAC sequence header based on stream data", 0, AV_OPT_TYPE_CONST, {.i64 = FLV_AAC_SEQ_HEADER_DETECT}, INT_MIN, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM, "flvflags" },
1054 { "no_sequence_end", "disable sequence end for FLV", 0, AV_OPT_TYPE_CONST, {.i64 = FLV_NO_SEQUENCE_END}, INT_MIN, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM, "flvflags" },
1055 { "no_metadata", "disable metadata for FLV", 0, AV_OPT_TYPE_CONST, {.i64 = FLV_NO_METADATA}, INT_MIN, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM, "flvflags" },
1056 { "no_duration_filesize", "disable duration and filesize zero value metadata for FLV", 0, AV_OPT_TYPE_CONST, {.i64 = FLV_NO_DURATION_FILESIZE}, INT_MIN, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM, "flvflags" },
1057 { "add_keyframe_index", "Add keyframe index metadata", 0, AV_OPT_TYPE_CONST, {.i64 = FLV_ADD_KEYFRAME_INDEX}, INT_MIN, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM, "flvflags" },
1058 { NULL },
1059 };
1060
1061 static const AVClass flv_muxer_class = {
1062 .class_name = "flv muxer",
1063 .item_name = av_default_item_name,
1064 .option = options,
1065 .version = LIBAVUTIL_VERSION_INT,
1066 };
1067
1068 const AVOutputFormat ff_flv_muxer = {
1069 .name = "flv",
1070 .long_name = NULL_IF_CONFIG_SMALL("FLV (Flash Video)"),
1071 .mime_type = "video/x-flv",
1072 .extensions = "flv",
1073 .priv_data_size = sizeof(FLVContext),
1074 .audio_codec = CONFIG_LIBMP3LAME ? AV_CODEC_ID_MP3 : AV_CODEC_ID_ADPCM_SWF,
1075 .video_codec = AV_CODEC_ID_FLV1,
1076 .init = flv_init,
1077 .write_header = flv_write_header,
1078 .write_packet = flv_write_packet,
1079 .write_trailer = flv_write_trailer,
1080 .deinit = flv_deinit,
1081 .check_bitstream= flv_check_bitstream,
1082 .codec_tag = (const AVCodecTag* const []) {
1083 flv_video_codec_ids, flv_audio_codec_ids, 0
1084 },
1085 .flags = AVFMT_GLOBALHEADER | AVFMT_VARIABLE_FPS |
1086 AVFMT_TS_NONSTRICT,
1087 .priv_class = &flv_muxer_class,
1088 };
1089