3 * Copyright (c) 2007 David Conrad
5 * This file is part of FFmpeg.
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.
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.
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
28 typedef struct mkv_seekhead_entry {
29 unsigned int elementid;
33 typedef struct mkv_seekhead {
35 offset_t segment_offset; ///< the file offset to the beginning of the segment
36 int reserved_size; ///< -1 if appending to file
38 mkv_seekhead_entry *entries;
45 offset_t cluster_pos; ///< file offset of the cluster containing the block
49 offset_t segment_offset;
50 mkv_cuepoint *entries;
54 typedef struct MatroskaMuxContext {
56 offset_t segment_offset;
58 offset_t cluster_pos; ///< file offset of the current cluster
60 offset_t duration_offset;
62 mkv_seekhead *main_seekhead;
63 mkv_seekhead *cluster_seekhead;
66 AVRandomState rand_state;
69 static void put_ebml_id(ByteIOContext *pb, unsigned int id)
72 put_byte(pb, id >> 24);
74 put_byte(pb, id >> 16);
76 put_byte(pb, id >> 8);
80 static int ebml_id_size(unsigned int id)
82 return (av_log2(id+1)-1)/7+1;
85 // XXX: test this thoroughly and get rid of minbytes hack (currently needed to
86 // use up all of the space reserved in start_ebml_master)
87 static void put_ebml_size(ByteIOContext *pb, uint64_t size, int minbytes)
91 // sizes larger than this are currently undefined in EBML
92 // so write "unknown" size
93 size = FFMIN(size, (1ULL<<56)-1);
95 while (size >> (bytes*7 + 7)) bytes++;
97 put_byte(pb, (0x80 >> bytes) | (size >> bytes*8));
98 for (bytes -= 1; bytes >= 0; bytes--)
99 put_byte(pb, size >> bytes*8);
102 static void put_ebml_uint(ByteIOContext *pb, unsigned int elementid, uint64_t val)
105 while (val >> bytes*8) bytes++;
107 put_ebml_id(pb, elementid);
108 put_ebml_size(pb, bytes, 0);
109 for (bytes -= 1; bytes >= 0; bytes--)
110 put_byte(pb, val >> bytes*8);
113 static void put_ebml_float(ByteIOContext *pb, unsigned int elementid, double val)
115 put_ebml_id(pb, elementid);
116 put_ebml_size(pb, 8, 0);
117 put_be64(pb, av_dbl2int(val));
120 static void put_ebml_binary(ByteIOContext *pb, unsigned int elementid,
121 const uint8_t *buf, int size)
123 put_ebml_id(pb, elementid);
124 put_ebml_size(pb, size, 0);
125 put_buffer(pb, buf, size);
128 static void put_ebml_string(ByteIOContext *pb, unsigned int elementid, const char *str)
130 put_ebml_binary(pb, elementid, str, strlen(str));
133 // this reserves exactly the amount of space specified by size, which must be at least 2
134 static void put_ebml_void(ByteIOContext *pb, uint64_t size)
136 offset_t currentpos = url_ftell(pb);
141 put_ebml_id(pb, EBML_ID_VOID);
142 // we need to subtract the length needed to store the size from the size we need to reserve
143 // so 2 cases, we use 8 bytes to store the size if possible, 1 byte otherwise
145 put_ebml_size(pb, size-1, 0);
147 put_ebml_size(pb, size-9, 7);
148 url_fseek(pb, currentpos + size, SEEK_SET);
151 static offset_t start_ebml_master(ByteIOContext *pb, unsigned int elementid)
153 put_ebml_id(pb, elementid);
154 // XXX: this always reserves the maximum needed space to store any size value
155 // we should be smarter (additional parameter for expected size?)
156 put_ebml_size(pb, (1ULL<<56)-1, 0); // largest unknown size
157 return url_ftell(pb);
160 static void end_ebml_master(ByteIOContext *pb, offset_t start)
162 offset_t pos = url_ftell(pb);
164 url_fseek(pb, start - 8, SEEK_SET);
165 put_ebml_size(pb, pos - start, 7);
166 url_fseek(pb, pos, SEEK_SET);
169 static void put_xiph_size(ByteIOContext *pb, int size)
172 for (i = 0; i < size / 255; i++)
174 put_byte(pb, size % 255);
177 // initializes a mkv_seekhead element to be ready to index level 1 matroska elements
178 // if numelements is greater than 0, it reserves enough space for that many elements
179 // at the current file position and writes the seekhead there, otherwise the seekhead
180 // will be appended to the file when end_mkv_seekhead() is called
181 static mkv_seekhead * mkv_start_seekhead(ByteIOContext *pb, offset_t segment_offset, int numelements)
183 mkv_seekhead *new_seekhead = av_mallocz(sizeof(mkv_seekhead));
184 if (new_seekhead == NULL)
187 new_seekhead->segment_offset = segment_offset;
189 if (numelements > 0) {
190 new_seekhead->filepos = url_ftell(pb);
191 // 21 bytes max for a seek entry, 10 bytes max for the SeekHead ID and size,
192 // and 3 bytes to guarantee that an EBML void element will fit afterwards
193 // XXX: 28 bytes right now because begin_ebml_master() reserves more than necessary
194 new_seekhead->reserved_size = numelements * 28 + 13;
195 new_seekhead->max_entries = numelements;
196 put_ebml_void(pb, new_seekhead->reserved_size);
201 static int mkv_add_seekhead_entry(mkv_seekhead *seekhead, unsigned int elementid, uint64_t filepos)
203 mkv_seekhead_entry *entries = seekhead->entries;
204 int new_entry = seekhead->num_entries;
206 // don't store more elements than we reserved space for
207 if (seekhead->max_entries > 0 && seekhead->max_entries <= seekhead->num_entries)
210 entries = av_realloc(entries, (seekhead->num_entries + 1) * sizeof(mkv_seekhead_entry));
214 entries[new_entry].elementid = elementid;
215 entries[new_entry].segmentpos = filepos - seekhead->segment_offset;
217 seekhead->entries = entries;
218 seekhead->num_entries++;
223 // returns the file offset where the seekhead was written and frees the seekhead
224 static offset_t mkv_write_seekhead(ByteIOContext *pb, mkv_seekhead *seekhead)
226 offset_t metaseek, seekentry, currentpos;
229 currentpos = url_ftell(pb);
231 if (seekhead->reserved_size > 0)
232 url_fseek(pb, seekhead->filepos, SEEK_SET);
234 metaseek = start_ebml_master(pb, MATROSKA_ID_SEEKHEAD);
235 for (i = 0; i < seekhead->num_entries; i++) {
236 mkv_seekhead_entry *entry = &seekhead->entries[i];
238 seekentry = start_ebml_master(pb, MATROSKA_ID_SEEKENTRY);
240 put_ebml_id(pb, MATROSKA_ID_SEEKID);
241 put_ebml_size(pb, ebml_id_size(entry->elementid), 0);
242 put_ebml_id(pb, entry->elementid);
244 put_ebml_uint(pb, MATROSKA_ID_SEEKPOSITION, entry->segmentpos);
245 end_ebml_master(pb, seekentry);
247 end_ebml_master(pb, metaseek);
249 if (seekhead->reserved_size > 0) {
250 uint64_t remaining = seekhead->filepos + seekhead->reserved_size - url_ftell(pb);
251 put_ebml_void(pb, remaining);
252 url_fseek(pb, currentpos, SEEK_SET);
254 currentpos = seekhead->filepos;
256 av_free(seekhead->entries);
262 static mkv_cues * mkv_start_cues(offset_t segment_offset)
264 mkv_cues *cues = av_mallocz(sizeof(mkv_cues));
268 cues->segment_offset = segment_offset;
272 static int mkv_add_cuepoint(mkv_cues *cues, AVPacket *pkt, offset_t cluster_pos)
274 mkv_cuepoint *entries = cues->entries;
275 int new_entry = cues->num_entries;
277 entries = av_realloc(entries, (cues->num_entries + 1) * sizeof(mkv_cuepoint));
281 entries[new_entry].pts = pkt->pts;
282 entries[new_entry].tracknum = pkt->stream_index + 1;
283 entries[new_entry].cluster_pos = cluster_pos - cues->segment_offset;
285 cues->entries = entries;
290 static offset_t mkv_write_cues(ByteIOContext *pb, mkv_cues *cues)
292 offset_t currentpos, cues_element;
295 currentpos = url_ftell(pb);
296 cues_element = start_ebml_master(pb, MATROSKA_ID_CUES);
298 for (i = 0; i < cues->num_entries; i++) {
299 offset_t cuepoint, track_positions;
300 mkv_cuepoint *entry = &cues->entries[i];
301 uint64_t pts = entry->pts;
303 cuepoint = start_ebml_master(pb, MATROSKA_ID_POINTENTRY);
304 put_ebml_uint(pb, MATROSKA_ID_CUETIME, pts);
306 // put all the entries from different tracks that have the exact same
307 // timestamp into the same CuePoint
308 for (j = 0; j < cues->num_entries - i && entry[j].pts == pts; j++) {
309 track_positions = start_ebml_master(pb, MATROSKA_ID_CUETRACKPOSITION);
310 put_ebml_uint(pb, MATROSKA_ID_CUETRACK , entry[j].tracknum );
311 put_ebml_uint(pb, MATROSKA_ID_CUECLUSTERPOSITION, entry[j].cluster_pos);
312 end_ebml_master(pb, track_positions);
315 end_ebml_master(pb, cuepoint);
317 end_ebml_master(pb, cues_element);
319 av_free(cues->entries);
324 static int put_xiph_codecpriv(ByteIOContext *pb, AVCodecContext *codec)
326 offset_t codecprivate;
327 uint8_t *header_start[3];
329 int first_header_size;
332 if (codec->codec_id == CODEC_ID_VORBIS)
333 first_header_size = 30;
335 first_header_size = 42;
337 if (ff_split_xiph_headers(codec->extradata, codec->extradata_size,
338 first_header_size, header_start, header_len) < 0) {
339 av_log(codec, AV_LOG_ERROR, "Extradata corrupt.\n");
343 codecprivate = start_ebml_master(pb, MATROSKA_ID_CODECPRIVATE);
344 put_byte(pb, 2); // number packets - 1
345 for (j = 0; j < 2; j++) {
346 put_xiph_size(pb, header_len[j]);
348 for (j = 0; j < 3; j++)
349 put_buffer(pb, header_start[j], header_len[j]);
350 end_ebml_master(pb, codecprivate);
355 #define FLAC_STREAMINFO_SIZE 34
357 static int put_flac_codecpriv(ByteIOContext *pb, AVCodecContext *codec)
359 offset_t codecpriv = start_ebml_master(pb, MATROSKA_ID_CODECPRIVATE);
361 // if the extradata_size is greater than FLAC_STREAMINFO_SIZE,
362 // assume that it's in Matroska's format already
363 if (codec->extradata_size < FLAC_STREAMINFO_SIZE) {
364 av_log(codec, AV_LOG_ERROR, "Invalid FLAC extradata\n");
366 } else if (codec->extradata_size == FLAC_STREAMINFO_SIZE) {
367 // only the streaminfo packet
369 put_xiph_size(pb, codec->extradata_size);
370 av_log(codec, AV_LOG_ERROR, "Only one packet\n");
372 put_buffer(pb, codec->extradata, codec->extradata_size);
373 end_ebml_master(pb, codecpriv);
377 static void get_aac_sample_rates(AVCodecContext *codec, int *sample_rate, int *output_sample_rate)
379 static const int aac_sample_rates[] = {
380 96000, 88200, 64000, 48000, 44100, 32000,
381 24000, 22050, 16000, 12000, 11025, 8000,
385 if (codec->extradata_size < 2) {
386 av_log(codec, AV_LOG_WARNING, "no aac extradata, unable to determine sample rate\n");
390 sri = ((codec->extradata[0] << 1) & 0xE) | (codec->extradata[1] >> 7);
392 av_log(codec, AV_LOG_WARNING, "aac samplerate index out of bounds\n");
395 *sample_rate = aac_sample_rates[sri];
397 // if sbr, get output sample rate as well
398 if (codec->extradata_size == 5) {
399 sri = (codec->extradata[4] >> 3) & 0xF;
401 av_log(codec, AV_LOG_WARNING, "aac output samplerate index out of bounds\n");
404 *output_sample_rate = aac_sample_rates[sri];
408 static int mkv_write_tracks(AVFormatContext *s)
410 MatroskaMuxContext *mkv = s->priv_data;
411 ByteIOContext *pb = &s->pb;
415 if (mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_TRACKS, url_ftell(pb)) < 0)
418 tracks = start_ebml_master(pb, MATROSKA_ID_TRACKS);
419 for (i = 0; i < s->nb_streams; i++) {
420 AVStream *st = s->streams[i];
421 AVCodecContext *codec = st->codec;
422 offset_t subinfo, track;
424 int bit_depth = av_get_bits_per_sample(codec->codec_id);
425 int sample_rate = codec->sample_rate;
426 int output_sample_rate = 0;
428 if (codec->codec_id == CODEC_ID_AAC)
429 get_aac_sample_rates(codec, &sample_rate, &output_sample_rate);
431 track = start_ebml_master(pb, MATROSKA_ID_TRACKENTRY);
432 put_ebml_uint (pb, MATROSKA_ID_TRACKNUMBER , i + 1);
433 put_ebml_uint (pb, MATROSKA_ID_TRACKUID , i + 1);
434 put_ebml_uint (pb, MATROSKA_ID_TRACKFLAGLACING , 0); // no lacing (yet)
437 put_ebml_string(pb, MATROSKA_ID_TRACKLANGUAGE, st->language);
439 // look for a codec id string specific to mkv to use, if none are found, use AVI codes
440 for (j = 0; ff_mkv_codec_tags[j].id != CODEC_ID_NONE; j++) {
441 if (ff_mkv_codec_tags[j].id == codec->codec_id) {
442 put_ebml_string(pb, MATROSKA_ID_CODECID, ff_mkv_codec_tags[j].str);
449 if (codec->codec_id == CODEC_ID_VORBIS || codec->codec_id == CODEC_ID_THEORA) {
450 if (put_xiph_codecpriv(pb, codec) < 0)
452 } else if (codec->codec_id == CODEC_ID_FLAC) {
453 if (put_flac_codecpriv(pb, codec) < 0)
455 } else if (codec->extradata_size) {
456 put_ebml_binary(pb, MATROSKA_ID_CODECPRIVATE, codec->extradata, codec->extradata_size);
460 switch (codec->codec_type) {
461 case CODEC_TYPE_VIDEO:
462 put_ebml_uint(pb, MATROSKA_ID_TRACKTYPE, MATROSKA_TRACK_TYPE_VIDEO);
466 // if there is no mkv-specific codec id, use VFW mode
467 if (!codec->codec_tag)
468 codec->codec_tag = codec_get_tag(codec_bmp_tags, codec->codec_id);
470 put_ebml_string(pb, MATROSKA_ID_CODECID, MATROSKA_CODEC_ID_VIDEO_VFW_FOURCC);
471 bmp_header = start_ebml_master(pb, MATROSKA_ID_CODECPRIVATE);
472 put_bmp_header(pb, codec, codec_bmp_tags, 0);
473 end_ebml_master(pb, bmp_header);
475 subinfo = start_ebml_master(pb, MATROSKA_ID_TRACKVIDEO);
476 // XXX: interlace flag?
477 put_ebml_uint (pb, MATROSKA_ID_VIDEOPIXELWIDTH , codec->width);
478 put_ebml_uint (pb, MATROSKA_ID_VIDEOPIXELHEIGHT, codec->height);
479 if (codec->sample_aspect_ratio.num) {
480 put_ebml_uint(pb, MATROSKA_ID_VIDEODISPLAYWIDTH , codec->sample_aspect_ratio.num);
481 put_ebml_uint(pb, MATROSKA_ID_VIDEODISPLAYHEIGHT, codec->sample_aspect_ratio.den);
483 end_ebml_master(pb, subinfo);
486 case CODEC_TYPE_AUDIO:
487 put_ebml_uint(pb, MATROSKA_ID_TRACKTYPE, MATROSKA_TRACK_TYPE_AUDIO);
491 // no mkv-specific ID, use ACM mode
492 codec->codec_tag = codec_get_tag(codec_wav_tags, codec->codec_id);
493 if (!codec->codec_tag) {
494 av_log(s, AV_LOG_ERROR, "no codec id found for stream %d", i);
498 put_ebml_string(pb, MATROSKA_ID_CODECID, MATROSKA_CODEC_ID_AUDIO_ACM);
499 wav_header = start_ebml_master(pb, MATROSKA_ID_CODECPRIVATE);
500 put_wav_header(pb, codec);
501 end_ebml_master(pb, wav_header);
503 subinfo = start_ebml_master(pb, MATROSKA_ID_TRACKAUDIO);
504 put_ebml_uint (pb, MATROSKA_ID_AUDIOCHANNELS , codec->channels);
505 put_ebml_float (pb, MATROSKA_ID_AUDIOSAMPLINGFREQ, sample_rate);
506 if (output_sample_rate)
507 put_ebml_float(pb, MATROSKA_ID_AUDIOOUTSAMPLINGFREQ, output_sample_rate);
509 put_ebml_uint(pb, MATROSKA_ID_AUDIOBITDEPTH, bit_depth);
510 end_ebml_master(pb, subinfo);
513 case CODEC_TYPE_SUBTITLE:
514 put_ebml_uint(pb, MATROSKA_ID_TRACKTYPE, MATROSKA_TRACK_TYPE_SUBTITLE);
517 av_log(s, AV_LOG_ERROR, "Only audio and video are supported for Matroska.");
520 end_ebml_master(pb, track);
522 // ms precision is the de-facto standard timescale for mkv files
523 av_set_pts_info(st, 64, 1, 1000);
525 end_ebml_master(pb, tracks);
529 static int mkv_write_header(AVFormatContext *s)
531 MatroskaMuxContext *mkv = s->priv_data;
532 ByteIOContext *pb = &s->pb;
533 offset_t ebml_header, segment_info;
536 av_init_random(av_gettime(), &mkv->rand_state);
538 ebml_header = start_ebml_master(pb, EBML_ID_HEADER);
539 put_ebml_uint (pb, EBML_ID_EBMLVERSION , 1);
540 put_ebml_uint (pb, EBML_ID_EBMLREADVERSION , 1);
541 put_ebml_uint (pb, EBML_ID_EBMLMAXIDLENGTH , 4);
542 put_ebml_uint (pb, EBML_ID_EBMLMAXSIZELENGTH , 8);
543 put_ebml_string (pb, EBML_ID_DOCTYPE , "matroska");
544 put_ebml_uint (pb, EBML_ID_DOCTYPEVERSION , 2);
545 put_ebml_uint (pb, EBML_ID_DOCTYPEREADVERSION , 2);
546 end_ebml_master(pb, ebml_header);
548 mkv->segment = start_ebml_master(pb, MATROSKA_ID_SEGMENT);
549 mkv->segment_offset = url_ftell(pb);
551 // we write 2 seek heads - one at the end of the file to point to each cluster, and
552 // one at the beginning to point to all other level one elements (including the seek
553 // head at the end of the file), which isn't more than 10 elements if we only write one
554 // of each other currently defined level 1 element
555 mkv->main_seekhead = mkv_start_seekhead(pb, mkv->segment_offset, 10);
556 mkv->cluster_seekhead = mkv_start_seekhead(pb, mkv->segment_offset, 0);
558 if (mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_INFO, url_ftell(pb)) < 0)
561 segment_info = start_ebml_master(pb, MATROSKA_ID_INFO);
562 put_ebml_uint(pb, MATROSKA_ID_TIMECODESCALE, 1000000);
563 if (strlen(s->title))
564 put_ebml_string(pb, MATROSKA_ID_TITLE, s->title);
565 if (!(s->streams[0]->codec->flags & CODEC_FLAG_BITEXACT)) {
566 uint8_t segmentuid[16];
567 for (i = 0; i < 16; i++)
568 segmentuid[i] = av_random(&mkv->rand_state);
570 put_ebml_string(pb, MATROSKA_ID_MUXINGAPP , LIBAVFORMAT_IDENT);
571 put_ebml_string(pb, MATROSKA_ID_WRITINGAPP, LIBAVFORMAT_IDENT);
572 put_ebml_binary(pb, MATROSKA_ID_SEGMENTUID, segmentuid, 16);
575 // reserve space for the duration
577 mkv->duration_offset = url_ftell(pb);
578 put_ebml_void(pb, 11); // assumes double-precision float to be written
579 end_ebml_master(pb, segment_info);
581 if (mkv_write_tracks(s) < 0)
584 if (mkv_add_seekhead_entry(mkv->cluster_seekhead, MATROSKA_ID_CLUSTER, url_ftell(pb)) < 0)
587 mkv->cluster_pos = url_ftell(pb);
588 mkv->cluster = start_ebml_master(pb, MATROSKA_ID_CLUSTER);
589 put_ebml_uint(pb, MATROSKA_ID_CLUSTERTIMECODE, 0);
590 mkv->cluster_pts = 0;
592 mkv->cues = mkv_start_cues(mkv->segment_offset);
593 if (mkv->cues == NULL)
599 static void mkv_write_block(AVFormatContext *s, unsigned int blockid, AVPacket *pkt, int flags)
601 MatroskaMuxContext *mkv = s->priv_data;
602 ByteIOContext *pb = &s->pb;
604 av_log(s, AV_LOG_DEBUG, "Writing block at offset %llu, size %d, pts %lld, dts %lld, duration %d, flags %d\n",
605 url_ftell(pb), pkt->size, pkt->pts, pkt->dts, pkt->duration, flags);
606 put_ebml_id(pb, blockid);
607 put_ebml_size(pb, pkt->size + 4, 0);
608 put_byte(pb, 0x80 | (pkt->stream_index + 1)); // this assumes stream_index is less than 126
609 put_be16(pb, pkt->pts - mkv->cluster_pts);
611 put_buffer(pb, pkt->data, pkt->size);
614 static int mkv_write_packet(AVFormatContext *s, AVPacket *pkt)
616 MatroskaMuxContext *mkv = s->priv_data;
617 ByteIOContext *pb = &s->pb;
618 AVCodecContext *codec = s->streams[pkt->stream_index]->codec;
619 int keyframe = !!(pkt->flags & PKT_FLAG_KEY);
621 // start a new cluster every 5 MB or 5 sec
622 if (url_ftell(pb) > mkv->cluster + 5*1024*1024 || pkt->pts > mkv->cluster_pts + 5000) {
623 av_log(s, AV_LOG_DEBUG, "Starting new cluster at offset %llu bytes, pts %llu\n", url_ftell(pb), pkt->pts);
624 end_ebml_master(pb, mkv->cluster);
626 if (mkv_add_seekhead_entry(mkv->cluster_seekhead, MATROSKA_ID_CLUSTER, url_ftell(pb)) < 0)
629 mkv->cluster_pos = url_ftell(pb);
630 mkv->cluster = start_ebml_master(pb, MATROSKA_ID_CLUSTER);
631 put_ebml_uint(pb, MATROSKA_ID_CLUSTERTIMECODE, pkt->pts);
632 mkv->cluster_pts = pkt->pts;
635 if (codec->codec_type != CODEC_TYPE_SUBTITLE) {
636 mkv_write_block(s, MATROSKA_ID_SIMPLEBLOCK, pkt, keyframe << 7);
638 offset_t blockgroup = start_ebml_master(pb, MATROSKA_ID_BLOCKGROUP);
639 mkv_write_block(s, MATROSKA_ID_BLOCK, pkt, 0);
640 put_ebml_uint(pb, MATROSKA_ID_DURATION, pkt->duration);
641 end_ebml_master(pb, blockgroup);
644 if (codec->codec_type == CODEC_TYPE_VIDEO && keyframe) {
645 if (mkv_add_cuepoint(mkv->cues, pkt, mkv->cluster_pos) < 0)
649 mkv->duration = pkt->pts + pkt->duration;
653 static int mkv_write_trailer(AVFormatContext *s)
655 MatroskaMuxContext *mkv = s->priv_data;
656 ByteIOContext *pb = &s->pb;
657 offset_t currentpos, second_seekhead, cuespos;
659 end_ebml_master(pb, mkv->cluster);
661 cuespos = mkv_write_cues(pb, mkv->cues);
662 second_seekhead = mkv_write_seekhead(pb, mkv->cluster_seekhead);
664 mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_CUES , cuespos);
665 mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_SEEKHEAD, second_seekhead);
666 mkv_write_seekhead(pb, mkv->main_seekhead);
668 // update the duration
669 av_log(s, AV_LOG_DEBUG, "end duration = %llu\n", mkv->duration);
670 currentpos = url_ftell(pb);
671 url_fseek(pb, mkv->duration_offset, SEEK_SET);
672 put_ebml_float(pb, MATROSKA_ID_DURATION, mkv->duration);
673 url_fseek(pb, currentpos, SEEK_SET);
675 end_ebml_master(pb, mkv->segment);
679 AVOutputFormat matroska_muxer = {
681 "Matroska File Format",
684 sizeof(MatroskaMuxContext),
690 .codec_tag = (const AVCodecTag*[]){codec_bmp_tags, codec_wav_tags, 0},
693 AVOutputFormat matroska_audio_muxer = {
695 "Matroska File Format",
698 sizeof(MatroskaMuxContext),
704 .codec_tag = (const AVCodecTag*[]){codec_wav_tags, 0},