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
26 #include "avio_internal.h"
27 #include "avlanguage.h"
33 #include "subtitles.h"
36 #include "libavutil/avstring.h"
37 #include "libavutil/dict.h"
38 #include "libavutil/intfloat.h"
39 #include "libavutil/intreadwrite.h"
40 #include "libavutil/lfg.h"
41 #include "libavutil/mathematics.h"
42 #include "libavutil/opt.h"
43 #include "libavutil/random_seed.h"
44 #include "libavutil/samplefmt.h"
45 #include "libavutil/sha.h"
47 #include "libavcodec/xiph.h"
48 #include "libavcodec/mpeg4audio.h"
49 #include "libavcodec/internal.h"
51 typedef struct ebml_master {
52 int64_t pos; ///< absolute offset in the file where the master's elements start
53 int sizebytes; ///< how many bytes were reserved for the size
56 typedef struct mkv_seekhead_entry {
57 unsigned int elementid;
61 typedef struct mkv_seekhead {
63 int64_t segment_offset; ///< the file offset to the beginning of the segment
64 int reserved_size; ///< -1 if appending to file
66 mkv_seekhead_entry *entries;
73 int64_t cluster_pos; ///< file offset of the cluster containing the block
74 int64_t relative_pos; ///< relative offset from the position of the cluster containing the block
75 int64_t duration; ///< duration of the block according to time base
79 int64_t segment_offset;
80 mkv_cuepoint *entries;
89 #define MODE_MATROSKAv2 0x01
90 #define MODE_WEBM 0x02
92 typedef struct MatroskaMuxContext {
97 int64_t segment_offset;
99 int64_t cluster_pos; ///< file offset of the current cluster
101 int64_t duration_offset;
103 mkv_seekhead *main_seekhead;
107 AVPacket cur_audio_pkt;
109 int have_attachments;
111 int reserve_cues_space;
112 int cluster_size_limit;
114 int64_t cluster_time_limit;
116 uint32_t chapter_id_offset;
118 } MatroskaMuxContext;
121 /** 2 bytes * 3 for EBML IDs, 3 1-byte EBML lengths, 8 bytes for 64 bit
122 * offset, 4 bytes for target EBML ID */
123 #define MAX_SEEKENTRY_SIZE 21
125 /** per-cuepoint-track - 5 1-byte EBML IDs, 5 1-byte EBML sizes, 4
127 #define MAX_CUETRACKPOS_SIZE 42
129 /** per-cuepoint - 2 1-byte EBML IDs, 2 1-byte EBML sizes, 8-byte uint max */
130 #define MAX_CUEPOINT_SIZE(num_tracks) 12 + MAX_CUETRACKPOS_SIZE*num_tracks
132 /** Seek preroll value for opus */
133 #define OPUS_SEEK_PREROLL 80000000
136 static int ebml_id_size(unsigned int id)
138 return (av_log2(id+1)-1)/7+1;
141 static void put_ebml_id(AVIOContext *pb, unsigned int id)
143 int i = ebml_id_size(id);
145 avio_w8(pb, (uint8_t)(id >> (i*8)));
149 * Write an EBML size meaning "unknown size".
151 * @param bytes The number of bytes the size should occupy (maximum: 8).
153 static void put_ebml_size_unknown(AVIOContext *pb, int bytes)
155 av_assert0(bytes <= 8);
156 avio_w8(pb, 0x1ff >> bytes);
157 ffio_fill(pb, 0xff, bytes - 1);
161 * Calculate how many bytes are needed to represent a given number in EBML.
163 static int ebml_num_size(uint64_t num)
166 while ((num+1) >> bytes*7) bytes++;
171 * Write a number in EBML variable length format.
173 * @param bytes The number of bytes that need to be used to write the number.
174 * If zero, any number of bytes can be used.
176 static void put_ebml_num(AVIOContext *pb, uint64_t num, int bytes)
178 int i, needed_bytes = ebml_num_size(num);
180 // sizes larger than this are currently undefined in EBML
181 av_assert0(num < (1ULL<<56)-1);
184 // don't care how many bytes are used, so use the min
185 bytes = needed_bytes;
186 // the bytes needed to write the given size would exceed the bytes
187 // that we need to use, so write unknown size. This shouldn't happen.
188 av_assert0(bytes >= needed_bytes);
190 num |= 1ULL << bytes*7;
191 for (i = bytes - 1; i >= 0; i--)
192 avio_w8(pb, (uint8_t)(num >> i*8));
195 static void put_ebml_uint(AVIOContext *pb, unsigned int elementid, uint64_t val)
199 while (tmp>>=8) bytes++;
201 put_ebml_id(pb, elementid);
202 put_ebml_num(pb, bytes, 0);
203 for (i = bytes - 1; i >= 0; i--)
204 avio_w8(pb, (uint8_t)(val >> i*8));
207 static void put_ebml_sint(AVIOContext *pb, unsigned int elementid, int64_t val)
210 uint64_t tmp = 2*(val < 0 ? val^-1 : val);
212 while (tmp>>=8) bytes++;
214 put_ebml_id(pb, elementid);
215 put_ebml_num(pb, bytes, 0);
216 for (i = bytes - 1; i >= 0; i--)
217 avio_w8(pb, (uint8_t)(val >> i*8));
220 static void put_ebml_float(AVIOContext *pb, unsigned int elementid, double val)
222 put_ebml_id(pb, elementid);
223 put_ebml_num(pb, 8, 0);
224 avio_wb64(pb, av_double2int(val));
227 static void put_ebml_binary(AVIOContext *pb, unsigned int elementid,
228 const void *buf, int size)
230 put_ebml_id(pb, elementid);
231 put_ebml_num(pb, size, 0);
232 avio_write(pb, buf, size);
235 static void put_ebml_string(AVIOContext *pb, unsigned int elementid, const char *str)
237 put_ebml_binary(pb, elementid, str, strlen(str));
241 * Write a void element of a given size. Useful for reserving space in
242 * the file to be written to later.
244 * @param size The number of bytes to reserve, which must be at least 2.
246 static void put_ebml_void(AVIOContext *pb, uint64_t size)
248 int64_t currentpos = avio_tell(pb);
250 av_assert0(size >= 2);
252 put_ebml_id(pb, EBML_ID_VOID);
253 // we need to subtract the length needed to store the size from the
254 // size we need to reserve so 2 cases, we use 8 bytes to store the
255 // size if possible, 1 byte otherwise
257 put_ebml_num(pb, size-1, 0);
259 put_ebml_num(pb, size-9, 8);
260 ffio_fill(pb, 0, currentpos + size - avio_tell(pb));
263 static ebml_master start_ebml_master(AVIOContext *pb, unsigned int elementid, uint64_t expectedsize)
265 int bytes = expectedsize ? ebml_num_size(expectedsize) : 8;
266 put_ebml_id(pb, elementid);
267 put_ebml_size_unknown(pb, bytes);
268 return (ebml_master){ avio_tell(pb), bytes };
271 static void end_ebml_master(AVIOContext *pb, ebml_master master)
273 int64_t pos = avio_tell(pb);
275 if (avio_seek(pb, master.pos - master.sizebytes, SEEK_SET) < 0)
277 put_ebml_num(pb, pos - master.pos, master.sizebytes);
278 avio_seek(pb, pos, SEEK_SET);
281 static void put_xiph_size(AVIOContext *pb, int size)
283 ffio_fill(pb, 255, size / 255);
284 avio_w8(pb, size % 255);
288 * Initialize a mkv_seekhead element to be ready to index level 1 Matroska
289 * elements. If a maximum number of elements is specified, enough space
290 * will be reserved at the current file location to write a seek head of
293 * @param segment_offset The absolute offset to the position in the file
294 * where the segment begins.
295 * @param numelements The maximum number of elements that will be indexed
296 * by this seek head, 0 if unlimited.
298 static mkv_seekhead * mkv_start_seekhead(AVIOContext *pb, int64_t segment_offset, int numelements)
300 mkv_seekhead *new_seekhead = av_mallocz(sizeof(mkv_seekhead));
301 if (new_seekhead == NULL)
304 new_seekhead->segment_offset = segment_offset;
306 if (numelements > 0) {
307 new_seekhead->filepos = avio_tell(pb);
308 // 21 bytes max for a seek entry, 10 bytes max for the SeekHead ID
309 // and size, and 3 bytes to guarantee that an EBML void element
310 // will fit afterwards
311 new_seekhead->reserved_size = numelements * MAX_SEEKENTRY_SIZE + 13;
312 new_seekhead->max_entries = numelements;
313 put_ebml_void(pb, new_seekhead->reserved_size);
318 static int mkv_add_seekhead_entry(mkv_seekhead *seekhead, unsigned int elementid, uint64_t filepos)
320 mkv_seekhead_entry *entries = seekhead->entries;
322 // don't store more elements than we reserved space for
323 if (seekhead->max_entries > 0 && seekhead->max_entries <= seekhead->num_entries)
326 entries = av_realloc_array(entries, seekhead->num_entries + 1, sizeof(mkv_seekhead_entry));
328 return AVERROR(ENOMEM);
329 seekhead->entries = entries;
331 seekhead->entries[seekhead->num_entries].elementid = elementid;
332 seekhead->entries[seekhead->num_entries++].segmentpos = filepos - seekhead->segment_offset;
338 * Write the seek head to the file and free it. If a maximum number of
339 * elements was specified to mkv_start_seekhead(), the seek head will
340 * be written at the location reserved for it. Otherwise, it is written
341 * at the current location in the file.
343 * @return The file offset where the seekhead was written,
344 * -1 if an error occurred.
346 static int64_t mkv_write_seekhead(AVIOContext *pb, mkv_seekhead *seekhead)
348 ebml_master metaseek, seekentry;
352 currentpos = avio_tell(pb);
354 if (seekhead->reserved_size > 0) {
355 if (avio_seek(pb, seekhead->filepos, SEEK_SET) < 0) {
361 metaseek = start_ebml_master(pb, MATROSKA_ID_SEEKHEAD, seekhead->reserved_size);
362 for (i = 0; i < seekhead->num_entries; i++) {
363 mkv_seekhead_entry *entry = &seekhead->entries[i];
365 seekentry = start_ebml_master(pb, MATROSKA_ID_SEEKENTRY, MAX_SEEKENTRY_SIZE);
367 put_ebml_id(pb, MATROSKA_ID_SEEKID);
368 put_ebml_num(pb, ebml_id_size(entry->elementid), 0);
369 put_ebml_id(pb, entry->elementid);
371 put_ebml_uint(pb, MATROSKA_ID_SEEKPOSITION, entry->segmentpos);
372 end_ebml_master(pb, seekentry);
374 end_ebml_master(pb, metaseek);
376 if (seekhead->reserved_size > 0) {
377 uint64_t remaining = seekhead->filepos + seekhead->reserved_size - avio_tell(pb);
378 put_ebml_void(pb, remaining);
379 avio_seek(pb, currentpos, SEEK_SET);
381 currentpos = seekhead->filepos;
384 av_freep(&seekhead->entries);
390 static mkv_cues * mkv_start_cues(int64_t segment_offset)
392 mkv_cues *cues = av_mallocz(sizeof(mkv_cues));
396 cues->segment_offset = segment_offset;
400 static int mkv_add_cuepoint(mkv_cues *cues, int stream, int64_t ts, int64_t cluster_pos, int64_t relative_pos,
403 mkv_cuepoint *entries = cues->entries;
408 entries = av_realloc_array(entries, cues->num_entries + 1, sizeof(mkv_cuepoint));
410 return AVERROR(ENOMEM);
411 cues->entries = entries;
413 cues->entries[cues->num_entries].pts = ts;
414 cues->entries[cues->num_entries].tracknum = stream + 1;
415 cues->entries[cues->num_entries].cluster_pos = cluster_pos - cues->segment_offset;
416 cues->entries[cues->num_entries].relative_pos = relative_pos;
417 cues->entries[cues->num_entries++].duration = duration;
422 static int64_t mkv_write_cues(AVIOContext *pb, mkv_cues *cues, mkv_track *tracks, int num_tracks)
424 ebml_master cues_element;
428 currentpos = avio_tell(pb);
429 cues_element = start_ebml_master(pb, MATROSKA_ID_CUES, 0);
431 for (i = 0; i < cues->num_entries; i++) {
432 ebml_master cuepoint, track_positions;
433 mkv_cuepoint *entry = &cues->entries[i];
434 uint64_t pts = entry->pts;
436 cuepoint = start_ebml_master(pb, MATROSKA_ID_POINTENTRY, MAX_CUEPOINT_SIZE(num_tracks));
437 put_ebml_uint(pb, MATROSKA_ID_CUETIME, pts);
439 // put all the entries from different tracks that have the exact same
440 // timestamp into the same CuePoint
441 for (j = 0; j < num_tracks; j++)
442 tracks[j].has_cue = 0;
443 for (j = 0; j < cues->num_entries - i && entry[j].pts == pts; j++) {
444 int tracknum = entry[j].tracknum - 1;
445 av_assert0(tracknum>=0 && tracknum<num_tracks);
446 if (tracks[tracknum].has_cue)
448 tracks[tracknum].has_cue = 1;
449 track_positions = start_ebml_master(pb, MATROSKA_ID_CUETRACKPOSITION, MAX_CUETRACKPOS_SIZE);
450 put_ebml_uint(pb, MATROSKA_ID_CUETRACK , entry[j].tracknum );
451 put_ebml_uint(pb, MATROSKA_ID_CUECLUSTERPOSITION , entry[j].cluster_pos);
452 put_ebml_uint(pb, MATROSKA_ID_CUERELATIVEPOSITION, entry[j].relative_pos);
453 if (entry[j].duration != -1)
454 put_ebml_uint(pb, MATROSKA_ID_CUEDURATION , entry[j].duration);
455 end_ebml_master(pb, track_positions);
458 end_ebml_master(pb, cuepoint);
460 end_ebml_master(pb, cues_element);
465 static int put_xiph_codecpriv(AVFormatContext *s, AVIOContext *pb, AVCodecContext *codec)
467 uint8_t *header_start[3];
469 int first_header_size;
472 if (codec->codec_id == AV_CODEC_ID_VORBIS)
473 first_header_size = 30;
475 first_header_size = 42;
477 if (avpriv_split_xiph_headers(codec->extradata, codec->extradata_size,
478 first_header_size, header_start, header_len) < 0) {
479 av_log(s, AV_LOG_ERROR, "Extradata corrupt.\n");
483 avio_w8(pb, 2); // number packets - 1
484 for (j = 0; j < 2; j++) {
485 put_xiph_size(pb, header_len[j]);
487 for (j = 0; j < 3; j++)
488 avio_write(pb, header_start[j], header_len[j]);
493 static int put_wv_codecpriv(AVIOContext *pb, AVCodecContext *codec)
495 if (codec->extradata && codec->extradata_size == 2)
496 avio_write(pb, codec->extradata, 2);
498 avio_wl16(pb, 0x403); // fallback to the version mentioned in matroska specs
502 static void get_aac_sample_rates(AVFormatContext *s, AVCodecContext *codec, int *sample_rate, int *output_sample_rate)
504 MPEG4AudioConfig mp4ac;
506 if (avpriv_mpeg4audio_get_config(&mp4ac, codec->extradata,
507 codec->extradata_size * 8, 1) < 0) {
508 av_log(s, AV_LOG_WARNING, "Error parsing AAC extradata, unable to determine samplerate.\n");
512 *sample_rate = mp4ac.sample_rate;
513 *output_sample_rate = mp4ac.ext_sample_rate;
516 static int mkv_write_codecprivate(AVFormatContext *s, AVIOContext *pb, AVCodecContext *codec, int native_id, int qt_id)
520 int ret, codecpriv_size;
522 ret = avio_open_dyn_buf(&dyn_cp);
527 if (codec->codec_id == AV_CODEC_ID_VORBIS || codec->codec_id == AV_CODEC_ID_THEORA)
528 ret = put_xiph_codecpriv(s, dyn_cp, codec);
529 else if (codec->codec_id == AV_CODEC_ID_FLAC)
530 ret = ff_flac_write_header(dyn_cp, codec, 1);
531 else if (codec->codec_id == AV_CODEC_ID_WAVPACK)
532 ret = put_wv_codecpriv(dyn_cp, codec);
533 else if (codec->codec_id == AV_CODEC_ID_H264)
534 ret = ff_isom_write_avcc(dyn_cp, codec->extradata, codec->extradata_size);
535 else if (codec->codec_id == AV_CODEC_ID_ALAC) {
536 if (codec->extradata_size < 36) {
537 av_log(s, AV_LOG_ERROR,
538 "Invalid extradata found, ALAC expects a 36-byte "
540 ret = AVERROR_INVALIDDATA;
542 avio_write(dyn_cp, codec->extradata + 12,
543 codec->extradata_size - 12);
545 else if (codec->extradata_size && codec->codec_id != AV_CODEC_ID_TTA)
546 avio_write(dyn_cp, codec->extradata, codec->extradata_size);
547 } else if (codec->codec_type == AVMEDIA_TYPE_VIDEO) {
549 if (!codec->codec_tag)
550 codec->codec_tag = ff_codec_get_tag(ff_codec_movvideo_tags, codec->codec_id);
551 if (codec->extradata_size)
552 avio_write(dyn_cp, codec->extradata, codec->extradata_size);
554 if (!ff_codec_get_tag(ff_codec_bmp_tags, codec->codec_id))
555 av_log(s, AV_LOG_WARNING, "codec %s is not supported by this format\n",
556 avcodec_get_name(codec->codec_id));
558 if (!codec->codec_tag)
559 codec->codec_tag = ff_codec_get_tag(ff_codec_bmp_tags, codec->codec_id);
560 if (!codec->codec_tag) {
561 av_log(s, AV_LOG_ERROR, "No bmp codec tag found for codec %s\n",
562 avcodec_get_name(codec->codec_id));
563 ret = AVERROR(EINVAL);
566 ff_put_bmp_header(dyn_cp, codec, ff_codec_bmp_tags, 0, 0);
569 } else if (codec->codec_type == AVMEDIA_TYPE_AUDIO) {
571 tag = ff_codec_get_tag(ff_codec_wav_tags, codec->codec_id);
573 av_log(s, AV_LOG_ERROR, "No wav codec tag found for codec %s\n",
574 avcodec_get_name(codec->codec_id));
575 ret = AVERROR(EINVAL);
577 if (!codec->codec_tag)
578 codec->codec_tag = tag;
580 ff_put_wav_header(dyn_cp, codec);
583 codecpriv_size = avio_close_dyn_buf(dyn_cp, &codecpriv);
585 put_ebml_binary(pb, MATROSKA_ID_CODECPRIVATE, codecpriv, codecpriv_size);
590 static int mkv_write_tracks(AVFormatContext *s)
592 MatroskaMuxContext *mkv = s->priv_data;
593 AVIOContext *pb = s->pb;
595 int i, j, ret, default_stream_exists = 0;
597 ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_TRACKS, avio_tell(pb));
598 if (ret < 0) return ret;
600 tracks = start_ebml_master(pb, MATROSKA_ID_TRACKS, 0);
601 for (i = 0; i < s->nb_streams; i++) {
602 AVStream *st = s->streams[i];
603 default_stream_exists |= st->disposition & AV_DISPOSITION_DEFAULT;
605 for (i = 0; i < s->nb_streams; i++) {
606 AVStream *st = s->streams[i];
607 AVCodecContext *codec = st->codec;
608 ebml_master subinfo, track;
611 int bit_depth = av_get_bits_per_sample(codec->codec_id);
612 int sample_rate = codec->sample_rate;
613 int output_sample_rate = 0;
614 int display_width_div = 1;
615 int display_height_div = 1;
616 AVDictionaryEntry *tag;
618 if (codec->codec_type == AVMEDIA_TYPE_ATTACHMENT) {
619 mkv->have_attachments = 1;
623 if (!bit_depth && codec->codec_id != AV_CODEC_ID_ADPCM_G726)
624 bit_depth = av_get_bytes_per_sample(codec->sample_fmt) << 3;
626 bit_depth = codec->bits_per_coded_sample;
628 if (codec->codec_id == AV_CODEC_ID_AAC)
629 get_aac_sample_rates(s, codec, &sample_rate, &output_sample_rate);
631 track = start_ebml_master(pb, MATROSKA_ID_TRACKENTRY, 0);
632 put_ebml_uint (pb, MATROSKA_ID_TRACKNUMBER , i + 1);
633 put_ebml_uint (pb, MATROSKA_ID_TRACKUID , i + 1);
634 put_ebml_uint (pb, MATROSKA_ID_TRACKFLAGLACING , 0); // no lacing (yet)
636 if ((tag = av_dict_get(st->metadata, "title", NULL, 0)))
637 put_ebml_string(pb, MATROSKA_ID_TRACKNAME, tag->value);
638 tag = av_dict_get(st->metadata, "language", NULL, 0);
639 if (mkv->mode != MODE_WEBM || codec->codec_id != AV_CODEC_ID_WEBVTT) {
640 put_ebml_string(pb, MATROSKA_ID_TRACKLANGUAGE, tag ? tag->value:"und");
641 } else if (tag && tag->value) {
642 put_ebml_string(pb, MATROSKA_ID_TRACKLANGUAGE, tag->value);
645 // The default value for TRACKFLAGDEFAULT is 1, so add element
646 // if we need to clear it.
647 if (default_stream_exists && !(st->disposition & AV_DISPOSITION_DEFAULT))
648 put_ebml_uint(pb, MATROSKA_ID_TRACKFLAGDEFAULT, !!(st->disposition & AV_DISPOSITION_DEFAULT));
650 if (st->disposition & AV_DISPOSITION_FORCED)
651 put_ebml_uint(pb, MATROSKA_ID_TRACKFLAGFORCED, 1);
653 if (mkv->mode == MODE_WEBM && codec->codec_id == AV_CODEC_ID_WEBVTT) {
654 const char *codec_id;
655 if (st->disposition & AV_DISPOSITION_CAPTIONS) {
656 codec_id = "D_WEBVTT/CAPTIONS";
657 native_id = MATROSKA_TRACK_TYPE_SUBTITLE;
658 } else if (st->disposition & AV_DISPOSITION_DESCRIPTIONS) {
659 codec_id = "D_WEBVTT/DESCRIPTIONS";
660 native_id = MATROSKA_TRACK_TYPE_METADATA;
661 } else if (st->disposition & AV_DISPOSITION_METADATA) {
662 codec_id = "D_WEBVTT/METADATA";
663 native_id = MATROSKA_TRACK_TYPE_METADATA;
665 codec_id = "D_WEBVTT/SUBTITLES";
666 native_id = MATROSKA_TRACK_TYPE_SUBTITLE;
668 put_ebml_string(pb, MATROSKA_ID_CODECID, codec_id);
670 // look for a codec ID string specific to mkv to use,
671 // if none are found, use AVI codes
672 for (j = 0; ff_mkv_codec_tags[j].id != AV_CODEC_ID_NONE; j++) {
673 if (ff_mkv_codec_tags[j].id == codec->codec_id) {
674 put_ebml_string(pb, MATROSKA_ID_CODECID, ff_mkv_codec_tags[j].str);
681 if (codec->codec_id == AV_CODEC_ID_OPUS) {
682 uint64_t codec_delay =av_rescale_q(codec->delay,
683 (AVRational){1, codec->sample_rate},
684 (AVRational){1, 1000000000});
685 put_ebml_uint(pb, MATROSKA_ID_CODECDELAY, codec_delay);
686 put_ebml_uint(pb, MATROSKA_ID_SEEKPREROLL, OPUS_SEEK_PREROLL);
690 if (mkv->mode == MODE_WEBM && !(codec->codec_id == AV_CODEC_ID_VP8 ||
691 codec->codec_id == AV_CODEC_ID_VP9 ||
692 ((codec->codec_id == AV_CODEC_ID_OPUS)&&(codec->strict_std_compliance <= FF_COMPLIANCE_EXPERIMENTAL)) ||
693 codec->codec_id == AV_CODEC_ID_VORBIS ||
694 codec->codec_id == AV_CODEC_ID_WEBVTT)) {
695 av_log(s, AV_LOG_ERROR,
696 "Only VP8,VP9 video and Vorbis,Opus(experimental, use -strict -2) audio and WebVTT subtitles are supported for WebM.\n");
697 return AVERROR(EINVAL);
700 switch (codec->codec_type) {
701 case AVMEDIA_TYPE_VIDEO:
702 put_ebml_uint(pb, MATROSKA_ID_TRACKTYPE, MATROSKA_TRACK_TYPE_VIDEO);
703 if(st->avg_frame_rate.num && st->avg_frame_rate.den && 1.0/av_q2d(st->avg_frame_rate) > av_q2d(codec->time_base))
704 put_ebml_uint(pb, MATROSKA_ID_TRACKDEFAULTDURATION, 1E9/av_q2d(st->avg_frame_rate));
706 put_ebml_uint(pb, MATROSKA_ID_TRACKDEFAULTDURATION, av_q2d(codec->time_base)*1E9);
709 ff_codec_get_tag(ff_codec_movvideo_tags, codec->codec_id) &&
710 (!ff_codec_get_tag(ff_codec_bmp_tags, codec->codec_id)
711 || codec->codec_id == AV_CODEC_ID_SVQ1
712 || codec->codec_id == AV_CODEC_ID_SVQ3
713 || codec->codec_id == AV_CODEC_ID_CINEPAK))
717 put_ebml_string(pb, MATROSKA_ID_CODECID, "V_QUICKTIME");
718 else if (!native_id) {
719 // if there is no mkv-specific codec ID, use VFW mode
720 put_ebml_string(pb, MATROSKA_ID_CODECID, "V_MS/VFW/FOURCC");
721 mkv->tracks[i].write_dts = 1;
724 subinfo = start_ebml_master(pb, MATROSKA_ID_TRACKVIDEO, 0);
725 // XXX: interlace flag?
726 put_ebml_uint (pb, MATROSKA_ID_VIDEOPIXELWIDTH , codec->width);
727 put_ebml_uint (pb, MATROSKA_ID_VIDEOPIXELHEIGHT, codec->height);
729 if ((tag = av_dict_get(st->metadata, "stereo_mode", NULL, 0)) ||
730 (tag = av_dict_get( s->metadata, "stereo_mode", NULL, 0))) {
731 // save stereo mode flag
732 uint64_t st_mode = MATROSKA_VIDEO_STEREO_MODE_COUNT;
734 for (j=0; j<MATROSKA_VIDEO_STEREO_MODE_COUNT; j++)
735 if (!strcmp(tag->value, ff_matroska_video_stereo_mode[j])){
740 if ((mkv->mode == MODE_WEBM && st_mode > 3 && st_mode != 11)
741 || st_mode >= MATROSKA_VIDEO_STEREO_MODE_COUNT) {
742 av_log(s, AV_LOG_ERROR,
743 "The specified stereo mode is not valid.\n");
744 return AVERROR(EINVAL);
746 put_ebml_uint(pb, MATROSKA_ID_VIDEOSTEREOMODE, st_mode);
753 display_width_div = 2;
759 display_height_div = 2;
764 if ((tag = av_dict_get(st->metadata, "alpha_mode", NULL, 0)) ||
765 (tag = av_dict_get( s->metadata, "alpha_mode", NULL, 0)) ||
766 (codec->pix_fmt == AV_PIX_FMT_YUVA420P)) {
767 put_ebml_uint(pb, MATROSKA_ID_VIDEOALPHAMODE, 1);
770 if (st->sample_aspect_ratio.num) {
771 int64_t d_width = av_rescale(codec->width, st->sample_aspect_ratio.num, st->sample_aspect_ratio.den);
772 if (d_width > INT_MAX) {
773 av_log(s, AV_LOG_ERROR, "Overflow in display width\n");
774 return AVERROR(EINVAL);
776 put_ebml_uint(pb, MATROSKA_ID_VIDEODISPLAYWIDTH , d_width / display_width_div);
777 put_ebml_uint(pb, MATROSKA_ID_VIDEODISPLAYHEIGHT, codec->height / display_height_div);
778 } else if (display_width_div != 1 || display_height_div != 1) {
779 put_ebml_uint(pb, MATROSKA_ID_VIDEODISPLAYWIDTH , codec->width / display_width_div);
780 put_ebml_uint(pb, MATROSKA_ID_VIDEODISPLAYHEIGHT, codec->height / display_height_div);
783 if (codec->codec_id == AV_CODEC_ID_RAWVIDEO) {
784 uint32_t color_space = av_le2ne32(codec->codec_tag);
785 put_ebml_binary(pb, MATROSKA_ID_VIDEOCOLORSPACE, &color_space, sizeof(color_space));
787 end_ebml_master(pb, subinfo);
790 case AVMEDIA_TYPE_AUDIO:
791 put_ebml_uint(pb, MATROSKA_ID_TRACKTYPE, MATROSKA_TRACK_TYPE_AUDIO);
794 // no mkv-specific ID, use ACM mode
795 put_ebml_string(pb, MATROSKA_ID_CODECID, "A_MS/ACM");
797 subinfo = start_ebml_master(pb, MATROSKA_ID_TRACKAUDIO, 0);
798 put_ebml_uint (pb, MATROSKA_ID_AUDIOCHANNELS , codec->channels);
799 put_ebml_float (pb, MATROSKA_ID_AUDIOSAMPLINGFREQ, sample_rate);
800 if (output_sample_rate)
801 put_ebml_float(pb, MATROSKA_ID_AUDIOOUTSAMPLINGFREQ, output_sample_rate);
803 put_ebml_uint(pb, MATROSKA_ID_AUDIOBITDEPTH, bit_depth);
804 end_ebml_master(pb, subinfo);
807 case AVMEDIA_TYPE_SUBTITLE:
809 av_log(s, AV_LOG_ERROR, "Subtitle codec %d is not supported.\n", codec->codec_id);
810 return AVERROR(ENOSYS);
813 if (mkv->mode != MODE_WEBM || codec->codec_id != AV_CODEC_ID_WEBVTT)
814 native_id = MATROSKA_TRACK_TYPE_SUBTITLE;
816 put_ebml_uint(pb, MATROSKA_ID_TRACKTYPE, native_id);
819 av_log(s, AV_LOG_ERROR, "Only audio, video, and subtitles are supported for Matroska.\n");
820 return AVERROR(EINVAL);
823 if (mkv->mode != MODE_WEBM || codec->codec_id != AV_CODEC_ID_WEBVTT) {
824 ret = mkv_write_codecprivate(s, pb, codec, native_id, qt_id);
825 if (ret < 0) return ret;
828 end_ebml_master(pb, track);
830 // ms precision is the de-facto standard timescale for mkv files
831 avpriv_set_pts_info(st, 64, 1, 1000);
833 end_ebml_master(pb, tracks);
837 static int mkv_write_chapters(AVFormatContext *s)
839 MatroskaMuxContext *mkv = s->priv_data;
840 AVIOContext *pb = s->pb;
841 ebml_master chapters, editionentry;
842 AVRational scale = {1, 1E9};
845 if (!s->nb_chapters || mkv->wrote_chapters)
848 ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_CHAPTERS, avio_tell(pb));
849 if (ret < 0) return ret;
851 chapters = start_ebml_master(pb, MATROSKA_ID_CHAPTERS , 0);
852 editionentry = start_ebml_master(pb, MATROSKA_ID_EDITIONENTRY, 0);
853 put_ebml_uint(pb, MATROSKA_ID_EDITIONFLAGDEFAULT, 1);
854 put_ebml_uint(pb, MATROSKA_ID_EDITIONFLAGHIDDEN , 0);
855 for (i = 0; i < s->nb_chapters; i++) {
856 ebml_master chapteratom, chapterdisplay;
857 AVChapter *c = s->chapters[i];
858 AVDictionaryEntry *t = NULL;
860 chapteratom = start_ebml_master(pb, MATROSKA_ID_CHAPTERATOM, 0);
861 put_ebml_uint(pb, MATROSKA_ID_CHAPTERUID, c->id + mkv->chapter_id_offset);
862 put_ebml_uint(pb, MATROSKA_ID_CHAPTERTIMESTART,
863 av_rescale_q(c->start, c->time_base, scale));
864 put_ebml_uint(pb, MATROSKA_ID_CHAPTERTIMEEND,
865 av_rescale_q(c->end, c->time_base, scale));
866 put_ebml_uint(pb, MATROSKA_ID_CHAPTERFLAGHIDDEN , 0);
867 put_ebml_uint(pb, MATROSKA_ID_CHAPTERFLAGENABLED, 1);
868 if ((t = av_dict_get(c->metadata, "title", NULL, 0))) {
869 chapterdisplay = start_ebml_master(pb, MATROSKA_ID_CHAPTERDISPLAY, 0);
870 put_ebml_string(pb, MATROSKA_ID_CHAPSTRING, t->value);
871 put_ebml_string(pb, MATROSKA_ID_CHAPLANG , "und");
872 end_ebml_master(pb, chapterdisplay);
874 end_ebml_master(pb, chapteratom);
876 end_ebml_master(pb, editionentry);
877 end_ebml_master(pb, chapters);
879 mkv->wrote_chapters = 1;
883 static void mkv_write_simpletag(AVIOContext *pb, AVDictionaryEntry *t)
885 uint8_t *key = av_strdup(t->key);
887 const uint8_t *lang = NULL;
890 if ((p = strrchr(p, '-')) &&
891 (lang = av_convert_lang_to(p + 1, AV_LANG_ISO639_2_BIBL)))
898 else if (*p >= 'a' && *p <= 'z')
903 tag = start_ebml_master(pb, MATROSKA_ID_SIMPLETAG, 0);
904 put_ebml_string(pb, MATROSKA_ID_TAGNAME, key);
906 put_ebml_string(pb, MATROSKA_ID_TAGLANG, lang);
907 put_ebml_string(pb, MATROSKA_ID_TAGSTRING, t->value);
908 end_ebml_master(pb, tag);
913 static int mkv_write_tag(AVFormatContext *s, AVDictionary *m, unsigned int elementid,
914 unsigned int uid, ebml_master *tags)
916 MatroskaMuxContext *mkv = s->priv_data;
917 ebml_master tag, targets;
918 AVDictionaryEntry *t = NULL;
922 ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_TAGS, avio_tell(s->pb));
923 if (ret < 0) return ret;
925 *tags = start_ebml_master(s->pb, MATROSKA_ID_TAGS, 0);
928 tag = start_ebml_master(s->pb, MATROSKA_ID_TAG, 0);
929 targets = start_ebml_master(s->pb, MATROSKA_ID_TAGTARGETS, 0);
931 put_ebml_uint(s->pb, elementid, uid);
932 end_ebml_master(s->pb, targets);
934 while ((t = av_dict_get(m, "", t, AV_DICT_IGNORE_SUFFIX)))
935 if (av_strcasecmp(t->key, "title") && av_strcasecmp(t->key, "stereo_mode"))
936 mkv_write_simpletag(s->pb, t);
938 end_ebml_master(s->pb, tag);
942 static int mkv_check_tag(AVDictionary *m)
944 AVDictionaryEntry *t = NULL;
946 while ((t = av_dict_get(m, "", t, AV_DICT_IGNORE_SUFFIX)))
947 if (av_strcasecmp(t->key, "title") && av_strcasecmp(t->key, "stereo_mode"))
953 static int mkv_write_tags(AVFormatContext *s)
955 MatroskaMuxContext *mkv = s->priv_data;
956 ebml_master tags = {0};
959 ff_metadata_conv_ctx(s, ff_mkv_metadata_conv, NULL);
961 if (mkv_check_tag(s->metadata)) {
962 ret = mkv_write_tag(s, s->metadata, 0, 0, &tags);
963 if (ret < 0) return ret;
966 for (i = 0; i < s->nb_streams; i++) {
967 AVStream *st = s->streams[i];
969 if (!mkv_check_tag(st->metadata))
972 ret = mkv_write_tag(s, st->metadata, MATROSKA_ID_TAGTARGETS_TRACKUID, i + 1, &tags);
973 if (ret < 0) return ret;
976 for (i = 0; i < s->nb_chapters; i++) {
977 AVChapter *ch = s->chapters[i];
979 if (!mkv_check_tag(ch->metadata))
982 ret = mkv_write_tag(s, ch->metadata, MATROSKA_ID_TAGTARGETS_CHAPTERUID, ch->id + mkv->chapter_id_offset, &tags);
983 if (ret < 0) return ret;
987 end_ebml_master(s->pb, tags);
991 static int mkv_write_attachments(AVFormatContext *s)
993 MatroskaMuxContext *mkv = s->priv_data;
994 AVIOContext *pb = s->pb;
995 ebml_master attachments;
999 if (!mkv->have_attachments)
1002 av_lfg_init(&c, av_get_random_seed());
1004 ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_ATTACHMENTS, avio_tell(pb));
1005 if (ret < 0) return ret;
1007 attachments = start_ebml_master(pb, MATROSKA_ID_ATTACHMENTS, 0);
1009 for (i = 0; i < s->nb_streams; i++) {
1010 AVStream *st = s->streams[i];
1011 ebml_master attached_file;
1012 AVDictionaryEntry *t;
1013 const char *mimetype = NULL;
1016 if (st->codec->codec_type != AVMEDIA_TYPE_ATTACHMENT)
1019 attached_file = start_ebml_master(pb, MATROSKA_ID_ATTACHEDFILE, 0);
1021 if (t = av_dict_get(st->metadata, "title", NULL, 0))
1022 put_ebml_string(pb, MATROSKA_ID_FILEDESC, t->value);
1023 if (!(t = av_dict_get(st->metadata, "filename", NULL, 0))) {
1024 av_log(s, AV_LOG_ERROR, "Attachment stream %d has no filename tag.\n", i);
1025 return AVERROR(EINVAL);
1027 put_ebml_string(pb, MATROSKA_ID_FILENAME, t->value);
1028 if (t = av_dict_get(st->metadata, "mimetype", NULL, 0))
1029 mimetype = t->value;
1030 else if (st->codec->codec_id != AV_CODEC_ID_NONE ) {
1032 for (i = 0; ff_mkv_mime_tags[i].id != AV_CODEC_ID_NONE; i++)
1033 if (ff_mkv_mime_tags[i].id == st->codec->codec_id) {
1034 mimetype = ff_mkv_mime_tags[i].str;
1039 av_log(s, AV_LOG_ERROR, "Attachment stream %d has no mimetype tag and "
1040 "it cannot be deduced from the codec id.\n", i);
1041 return AVERROR(EINVAL);
1044 if (st->codec->flags & CODEC_FLAG_BITEXACT) {
1045 struct AVSHA *sha = av_sha_alloc();
1048 return AVERROR(ENOMEM);
1049 av_sha_init(sha, 160);
1050 av_sha_update(sha, st->codec->extradata, st->codec->extradata_size);
1051 av_sha_final(sha, digest);
1053 fileuid = AV_RL64(digest);
1055 fileuid = av_lfg_get(&c);
1057 av_log(s, AV_LOG_VERBOSE, "Using %.16"PRIx64" for attachment %d\n",
1060 put_ebml_string(pb, MATROSKA_ID_FILEMIMETYPE, mimetype);
1061 put_ebml_binary(pb, MATROSKA_ID_FILEDATA, st->codec->extradata, st->codec->extradata_size);
1062 put_ebml_uint(pb, MATROSKA_ID_FILEUID, fileuid);
1063 end_ebml_master(pb, attached_file);
1065 end_ebml_master(pb, attachments);
1070 static int mkv_write_header(AVFormatContext *s)
1072 MatroskaMuxContext *mkv = s->priv_data;
1073 AVIOContext *pb = s->pb;
1074 ebml_master ebml_header, segment_info;
1075 AVDictionaryEntry *tag;
1078 if (!strcmp(s->oformat->name, "webm")) mkv->mode = MODE_WEBM;
1079 else mkv->mode = MODE_MATROSKAv2;
1081 if (s->avoid_negative_ts < 0)
1082 s->avoid_negative_ts = 1;
1084 for (i = 0; i < s->nb_streams; i++)
1085 if (s->streams[i]->codec->codec_id == AV_CODEC_ID_ATRAC3 ||
1086 s->streams[i]->codec->codec_id == AV_CODEC_ID_COOK ||
1087 s->streams[i]->codec->codec_id == AV_CODEC_ID_RA_288 ||
1088 s->streams[i]->codec->codec_id == AV_CODEC_ID_SIPR ||
1089 s->streams[i]->codec->codec_id == AV_CODEC_ID_RV10 ||
1090 s->streams[i]->codec->codec_id == AV_CODEC_ID_RV20) {
1091 av_log(s, AV_LOG_ERROR,
1092 "The Matroska muxer does not yet support muxing %s\n",
1093 avcodec_get_name(s->streams[i]->codec->codec_id));
1094 return AVERROR_PATCHWELCOME;
1097 mkv->tracks = av_mallocz(s->nb_streams * sizeof(*mkv->tracks));
1099 return AVERROR(ENOMEM);
1101 ebml_header = start_ebml_master(pb, EBML_ID_HEADER, 0);
1102 put_ebml_uint (pb, EBML_ID_EBMLVERSION , 1);
1103 put_ebml_uint (pb, EBML_ID_EBMLREADVERSION , 1);
1104 put_ebml_uint (pb, EBML_ID_EBMLMAXIDLENGTH , 4);
1105 put_ebml_uint (pb, EBML_ID_EBMLMAXSIZELENGTH , 8);
1106 put_ebml_string (pb, EBML_ID_DOCTYPE , s->oformat->name);
1107 put_ebml_uint (pb, EBML_ID_DOCTYPEVERSION , 4);
1108 put_ebml_uint (pb, EBML_ID_DOCTYPEREADVERSION , 2);
1109 end_ebml_master(pb, ebml_header);
1111 mkv->segment = start_ebml_master(pb, MATROSKA_ID_SEGMENT, 0);
1112 mkv->segment_offset = avio_tell(pb);
1114 // we write 2 seek heads - one at the end of the file to point to each
1115 // cluster, and one at the beginning to point to all other level one
1116 // elements (including the seek head at the end of the file), which
1117 // isn't more than 10 elements if we only write one of each other
1118 // currently defined level 1 element
1119 mkv->main_seekhead = mkv_start_seekhead(pb, mkv->segment_offset, 10);
1120 if (!mkv->main_seekhead)
1121 return AVERROR(ENOMEM);
1123 ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_INFO, avio_tell(pb));
1124 if (ret < 0) return ret;
1126 segment_info = start_ebml_master(pb, MATROSKA_ID_INFO, 0);
1127 put_ebml_uint(pb, MATROSKA_ID_TIMECODESCALE, 1000000);
1128 if ((tag = av_dict_get(s->metadata, "title", NULL, 0)))
1129 put_ebml_string(pb, MATROSKA_ID_TITLE, tag->value);
1130 if (!(s->streams[0]->codec->flags & CODEC_FLAG_BITEXACT)) {
1131 uint32_t segment_uid[4];
1134 av_lfg_init(&lfg, av_get_random_seed());
1136 for (i = 0; i < 4; i++)
1137 segment_uid[i] = av_lfg_get(&lfg);
1139 put_ebml_string(pb, MATROSKA_ID_MUXINGAPP , LIBAVFORMAT_IDENT);
1140 put_ebml_string(pb, MATROSKA_ID_WRITINGAPP, LIBAVFORMAT_IDENT);
1141 put_ebml_binary(pb, MATROSKA_ID_SEGMENTUID, segment_uid, 16);
1143 const char *ident = "Lavf";
1144 put_ebml_string(pb, MATROSKA_ID_MUXINGAPP , ident);
1145 put_ebml_string(pb, MATROSKA_ID_WRITINGAPP, ident);
1148 if (tag = av_dict_get(s->metadata, "creation_time", NULL, 0)) {
1149 // Adjust time so it's relative to 2001-01-01 and convert to nanoseconds.
1150 int64_t date_utc = (ff_iso8601_to_unix_time(tag->value) - 978307200) * 1000000000;
1151 uint8_t date_utc_buf[8];
1152 AV_WB64(date_utc_buf, date_utc);
1153 put_ebml_binary(pb, MATROSKA_ID_DATEUTC, date_utc_buf, 8);
1156 // reserve space for the duration
1158 mkv->duration_offset = avio_tell(pb);
1159 put_ebml_void(pb, 11); // assumes double-precision float to be written
1160 end_ebml_master(pb, segment_info);
1162 ret = mkv_write_tracks(s);
1163 if (ret < 0) return ret;
1165 for (i = 0; i < s->nb_chapters; i++)
1166 mkv->chapter_id_offset = FFMAX(mkv->chapter_id_offset, 1LL - s->chapters[i]->id);
1168 if (mkv->mode != MODE_WEBM) {
1169 ret = mkv_write_chapters(s);
1170 if (ret < 0) return ret;
1172 ret = mkv_write_tags(s);
1173 if (ret < 0) return ret;
1175 ret = mkv_write_attachments(s);
1176 if (ret < 0) return ret;
1179 if (!s->pb->seekable)
1180 mkv_write_seekhead(pb, mkv->main_seekhead);
1182 mkv->cues = mkv_start_cues(mkv->segment_offset);
1183 if (mkv->cues == NULL)
1184 return AVERROR(ENOMEM);
1186 if (pb->seekable && mkv->reserve_cues_space) {
1187 mkv->cues_pos = avio_tell(pb);
1188 put_ebml_void(pb, mkv->reserve_cues_space);
1191 av_init_packet(&mkv->cur_audio_pkt);
1192 mkv->cur_audio_pkt.size = 0;
1193 mkv->cluster_pos = -1;
1197 // start a new cluster every 5 MB or 5 sec, or 32k / 1 sec for streaming or
1198 // after 4k and on a keyframe
1200 if (mkv->cluster_time_limit < 0)
1201 mkv->cluster_time_limit = 5000;
1202 if (mkv->cluster_size_limit < 0)
1203 mkv->cluster_size_limit = 5 * 1024 * 1024;
1205 if (mkv->cluster_time_limit < 0)
1206 mkv->cluster_time_limit = 1000;
1207 if (mkv->cluster_size_limit < 0)
1208 mkv->cluster_size_limit = 32 * 1024;
1214 static int mkv_blockgroup_size(int pkt_size)
1216 int size = pkt_size + 4;
1217 size += ebml_num_size(size);
1218 size += 2; // EBML ID for block and block duration
1219 size += 8; // max size of block duration
1220 size += ebml_num_size(size);
1221 size += 1; // blockgroup EBML ID
1225 static int ass_get_duration(const uint8_t *p)
1227 int sh, sm, ss, sc, eh, em, es, ec;
1228 uint64_t start, end;
1230 if (sscanf(p, "%*[^,],%d:%d:%d%*c%d,%d:%d:%d%*c%d",
1231 &sh, &sm, &ss, &sc, &eh, &em, &es, &ec) != 8)
1233 start = 3600000LL*sh + 60000LL*sm + 1000LL*ss + 10LL*sc;
1234 end = 3600000LL*eh + 60000LL*em + 1000LL*es + 10LL*ec;
1239 static int mkv_write_ass_blocks(AVFormatContext *s, AVIOContext *pb, AVPacket *pkt)
1241 MatroskaMuxContext *mkv = s->priv_data;
1242 int i, layer = 0, max_duration = 0, size, line_size, data_size = pkt->size;
1243 uint8_t *start, *end, *data = pkt->data;
1244 ebml_master blockgroup;
1248 int duration = ass_get_duration(data);
1249 max_duration = FFMAX(duration, max_duration);
1250 end = memchr(data, '\n', data_size);
1251 size = line_size = end ? end-data+1 : data_size;
1252 size -= end ? (end[-1]=='\r')+1 : 0;
1254 for (i=0; i<3; i++, start++)
1255 if (!(start = memchr(start, ',', size-(start-data))))
1256 return max_duration;
1257 size -= start - data;
1258 sscanf(data, "Dialogue: %d,", &layer);
1259 i = snprintf(buffer, sizeof(buffer), "%"PRId64",%d,",
1260 s->streams[pkt->stream_index]->nb_frames, layer);
1261 size = FFMIN(i+size, sizeof(buffer));
1262 memcpy(buffer+i, start, size-i);
1264 av_log(s, AV_LOG_DEBUG, "Writing block at offset %" PRIu64 ", size %d, "
1265 "pts %" PRId64 ", duration %d\n",
1266 avio_tell(pb), size, pkt->pts, duration);
1267 blockgroup = start_ebml_master(pb, MATROSKA_ID_BLOCKGROUP, mkv_blockgroup_size(size));
1268 put_ebml_id(pb, MATROSKA_ID_BLOCK);
1269 put_ebml_num(pb, size+4, 0);
1270 avio_w8(pb, 0x80 | (pkt->stream_index + 1)); // this assumes stream_index is less than 126
1271 avio_wb16(pb, pkt->pts - mkv->cluster_pts);
1273 avio_write(pb, buffer, size);
1274 put_ebml_uint(pb, MATROSKA_ID_BLOCKDURATION, duration);
1275 end_ebml_master(pb, blockgroup);
1278 data_size -= line_size;
1281 return max_duration;
1285 static int mkv_strip_wavpack(const uint8_t *src, uint8_t **pdst, int *size)
1292 dst = av_malloc(srclen);
1294 return AVERROR(ENOMEM);
1296 while (srclen >= WV_HEADER_SIZE) {
1299 ret = ff_wv_parse_header(&header, src);
1302 src += WV_HEADER_SIZE;
1303 srclen -= WV_HEADER_SIZE;
1305 if (srclen < header.blocksize) {
1306 ret = AVERROR_INVALIDDATA;
1310 if (header.initial) {
1311 AV_WL32(dst + offset, header.samples);
1314 AV_WL32(dst + offset, header.flags);
1315 AV_WL32(dst + offset + 4, header.crc);
1318 if (!(header.initial && header.final)) {
1319 AV_WL32(dst + offset, header.blocksize);
1323 memcpy(dst + offset, src, header.blocksize);
1324 src += header.blocksize;
1325 srclen -= header.blocksize;
1326 offset += header.blocksize;
1338 static void mkv_write_block(AVFormatContext *s, AVIOContext *pb,
1339 unsigned int blockid, AVPacket *pkt, int flags)
1341 MatroskaMuxContext *mkv = s->priv_data;
1342 AVCodecContext *codec = s->streams[pkt->stream_index]->codec;
1343 uint8_t *data = NULL, *side_data = NULL;
1344 int offset = 0, size = pkt->size, side_data_size = 0;
1345 int64_t ts = mkv->tracks[pkt->stream_index].write_dts ? pkt->dts : pkt->pts;
1346 uint64_t additional_id = 0;
1347 int64_t discard_padding = 0;
1348 ebml_master block_group, block_additions, block_more;
1350 av_log(s, AV_LOG_DEBUG, "Writing block at offset %" PRIu64 ", size %d, "
1351 "pts %" PRId64 ", dts %" PRId64 ", duration %d, flags %d\n",
1352 avio_tell(pb), pkt->size, pkt->pts, pkt->dts, pkt->duration, flags);
1353 if (codec->codec_id == AV_CODEC_ID_H264 && codec->extradata_size > 0 &&
1354 (AV_RB24(codec->extradata) == 1 || AV_RB32(codec->extradata) == 1))
1355 ff_avc_parse_nal_units_buf(pkt->data, &data, &size);
1356 else if (codec->codec_id == AV_CODEC_ID_WAVPACK) {
1357 int ret = mkv_strip_wavpack(pkt->data, &data, &size);
1359 av_log(s, AV_LOG_ERROR, "Error stripping a WavPack packet.\n");
1365 if (codec->codec_id == AV_CODEC_ID_PRORES) {
1366 /* Matroska specification requires to remove the first QuickTime atom
1372 side_data = av_packet_get_side_data(pkt,
1373 AV_PKT_DATA_SKIP_SAMPLES,
1376 if (side_data && side_data_size >= 10) {
1377 discard_padding = av_rescale_q(AV_RL32(side_data + 4),
1378 (AVRational){1, codec->sample_rate},
1379 (AVRational){1, 1000000000});
1382 side_data = av_packet_get_side_data(pkt,
1383 AV_PKT_DATA_MATROSKA_BLOCKADDITIONAL,
1386 additional_id = AV_RB64(side_data);
1388 side_data_size -= 8;
1391 if ((side_data_size && additional_id == 1) || discard_padding) {
1392 block_group = start_ebml_master(pb, MATROSKA_ID_BLOCKGROUP, 0);
1393 blockid = MATROSKA_ID_BLOCK;
1396 put_ebml_id(pb, blockid);
1397 put_ebml_num(pb, size+4, 0);
1398 avio_w8(pb, 0x80 | (pkt->stream_index + 1)); // this assumes stream_index is less than 126
1399 avio_wb16(pb, ts - mkv->cluster_pts);
1401 avio_write(pb, data + offset, size);
1402 if (data != pkt->data)
1405 if (discard_padding) {
1406 put_ebml_sint(pb, MATROSKA_ID_DISCARDPADDING, discard_padding);
1409 if (side_data_size && additional_id == 1) {
1410 block_additions = start_ebml_master(pb, MATROSKA_ID_BLOCKADDITIONS, 0);
1411 block_more = start_ebml_master(pb, MATROSKA_ID_BLOCKMORE, 0);
1412 put_ebml_uint(pb, MATROSKA_ID_BLOCKADDID, 1);
1413 put_ebml_id(pb, MATROSKA_ID_BLOCKADDITIONAL);
1414 put_ebml_num(pb, side_data_size, 0);
1415 avio_write(pb, side_data, side_data_size);
1416 end_ebml_master(pb, block_more);
1417 end_ebml_master(pb, block_additions);
1419 if ((side_data_size && additional_id == 1) || discard_padding) {
1420 end_ebml_master(pb, block_group);
1424 static int srt_get_duration(uint8_t **buf)
1426 int i, duration = 0;
1428 for (i=0; i<2 && !duration; i++) {
1429 int s_hour, s_min, s_sec, s_hsec, e_hour, e_min, e_sec, e_hsec;
1430 if (sscanf(*buf, "%d:%2d:%2d%*1[,.]%3d --> %d:%2d:%2d%*1[,.]%3d",
1431 &s_hour, &s_min, &s_sec, &s_hsec,
1432 &e_hour, &e_min, &e_sec, &e_hsec) == 8) {
1433 s_min += 60*s_hour; e_min += 60*e_hour;
1434 s_sec += 60*s_min; e_sec += 60*e_min;
1435 s_hsec += 1000*s_sec; e_hsec += 1000*e_sec;
1436 duration = e_hsec - s_hsec;
1438 *buf += ff_subtitles_next_line(*buf);
1443 static int mkv_write_srt_blocks(AVFormatContext *s, AVIOContext *pb, AVPacket *pkt)
1445 ebml_master blockgroup;
1446 AVPacket pkt2 = *pkt;
1447 int64_t duration = srt_get_duration(&pkt2.data);
1448 pkt2.size -= pkt2.data - pkt->data;
1450 blockgroup = start_ebml_master(pb, MATROSKA_ID_BLOCKGROUP,
1451 mkv_blockgroup_size(pkt2.size));
1452 mkv_write_block(s, pb, MATROSKA_ID_BLOCK, &pkt2, 0);
1453 put_ebml_uint(pb, MATROSKA_ID_BLOCKDURATION, duration);
1454 end_ebml_master(pb, blockgroup);
1459 static int mkv_write_vtt_blocks(AVFormatContext *s, AVIOContext *pb, AVPacket *pkt)
1461 MatroskaMuxContext *mkv = s->priv_data;
1462 ebml_master blockgroup;
1463 int id_size, settings_size, size;
1464 uint8_t *id, *settings;
1465 int64_t ts = mkv->tracks[pkt->stream_index].write_dts ? pkt->dts : pkt->pts;
1466 const int flags = 0;
1469 id = av_packet_get_side_data(pkt, AV_PKT_DATA_WEBVTT_IDENTIFIER,
1473 settings = av_packet_get_side_data(pkt, AV_PKT_DATA_WEBVTT_SETTINGS,
1476 size = id_size + 1 + settings_size + 1 + pkt->size;
1478 av_log(s, AV_LOG_DEBUG, "Writing block at offset %" PRIu64 ", size %d, "
1479 "pts %" PRId64 ", dts %" PRId64 ", duration %d, flags %d\n",
1480 avio_tell(pb), size, pkt->pts, pkt->dts, pkt->duration, flags);
1482 blockgroup = start_ebml_master(pb, MATROSKA_ID_BLOCKGROUP, mkv_blockgroup_size(size));
1484 put_ebml_id(pb, MATROSKA_ID_BLOCK);
1485 put_ebml_num(pb, size+4, 0);
1486 avio_w8(pb, 0x80 | (pkt->stream_index + 1)); // this assumes stream_index is less than 126
1487 avio_wb16(pb, ts - mkv->cluster_pts);
1489 avio_printf(pb, "%.*s\n%.*s\n%.*s", id_size, id, settings_size, settings, pkt->size, pkt->data);
1491 put_ebml_uint(pb, MATROSKA_ID_BLOCKDURATION, pkt->duration);
1492 end_ebml_master(pb, blockgroup);
1494 return pkt->duration;
1497 static void mkv_flush_dynbuf(AVFormatContext *s)
1499 MatroskaMuxContext *mkv = s->priv_data;
1506 bufsize = avio_close_dyn_buf(mkv->dyn_bc, &dyn_buf);
1507 avio_write(s->pb, dyn_buf, bufsize);
1512 static int mkv_write_packet_internal(AVFormatContext *s, AVPacket *pkt)
1514 MatroskaMuxContext *mkv = s->priv_data;
1515 AVIOContext *pb = s->pb;
1516 AVCodecContext *codec = s->streams[pkt->stream_index]->codec;
1517 int keyframe = !!(pkt->flags & AV_PKT_FLAG_KEY);
1518 int duration = pkt->duration;
1520 int64_t ts = mkv->tracks[pkt->stream_index].write_dts ? pkt->dts : pkt->pts;
1521 int64_t relative_packet_pos;
1523 if (ts == AV_NOPTS_VALUE) {
1524 av_log(s, AV_LOG_ERROR, "Can't write packet with unknown timestamp\n");
1525 return AVERROR(EINVAL);
1528 if (!s->pb->seekable) {
1530 if ((ret = avio_open_dyn_buf(&mkv->dyn_bc)) < 0) {
1531 av_log(s, AV_LOG_ERROR, "Failed to open dynamic buffer\n");
1538 if (mkv->cluster_pos == -1) {
1539 mkv->cluster_pos = avio_tell(s->pb);
1540 mkv->cluster = start_ebml_master(pb, MATROSKA_ID_CLUSTER, 0);
1541 put_ebml_uint(pb, MATROSKA_ID_CLUSTERTIMECODE, FFMAX(0, ts));
1542 mkv->cluster_pts = FFMAX(0, ts);
1545 relative_packet_pos = avio_tell(s->pb) - mkv->cluster.pos;
1547 if (codec->codec_type != AVMEDIA_TYPE_SUBTITLE) {
1548 mkv_write_block(s, pb, MATROSKA_ID_SIMPLEBLOCK, pkt, keyframe << 7);
1550 } else if (codec->codec_id == AV_CODEC_ID_SSA) {
1551 duration = mkv_write_ass_blocks(s, pb, pkt);
1553 } else if (codec->codec_id == AV_CODEC_ID_SRT) {
1554 duration = mkv_write_srt_blocks(s, pb, pkt);
1555 } else if (codec->codec_id == AV_CODEC_ID_WEBVTT) {
1556 duration = mkv_write_vtt_blocks(s, pb, pkt);
1558 ebml_master blockgroup = start_ebml_master(pb, MATROSKA_ID_BLOCKGROUP, mkv_blockgroup_size(pkt->size));
1559 /* For backward compatibility, prefer convergence_duration. */
1560 if (pkt->convergence_duration > 0) {
1561 duration = pkt->convergence_duration;
1563 mkv_write_block(s, pb, MATROSKA_ID_BLOCK, pkt, 0);
1564 put_ebml_uint(pb, MATROSKA_ID_BLOCKDURATION, duration);
1565 end_ebml_master(pb, blockgroup);
1568 if ((codec->codec_type == AVMEDIA_TYPE_VIDEO && keyframe) || codec->codec_type == AVMEDIA_TYPE_SUBTITLE) {
1569 ret = mkv_add_cuepoint(mkv->cues, pkt->stream_index, ts, mkv->cluster_pos, relative_packet_pos,
1570 codec->codec_type == AVMEDIA_TYPE_SUBTITLE ? duration : -1);
1571 if (ret < 0) return ret;
1574 mkv->duration = FFMAX(mkv->duration, ts + duration);
1578 static int mkv_write_packet(AVFormatContext *s, AVPacket *pkt)
1580 MatroskaMuxContext *mkv = s->priv_data;
1581 int codec_type = s->streams[pkt->stream_index]->codec->codec_type;
1582 int keyframe = !!(pkt->flags & AV_PKT_FLAG_KEY);
1584 int64_t cluster_time;
1588 if (mkv->tracks[pkt->stream_index].write_dts)
1589 cluster_time = pkt->dts - mkv->cluster_pts;
1591 cluster_time = pkt->pts - mkv->cluster_pts;
1593 // start a new cluster every 5 MB or 5 sec, or 32k / 1 sec for streaming or
1594 // after 4k and on a keyframe
1595 if (s->pb->seekable) {
1597 cluster_size = avio_tell(pb) - mkv->cluster_pos;
1600 cluster_size = avio_tell(pb);
1603 if (mkv->cluster_pos != -1 &&
1604 (cluster_size > mkv->cluster_size_limit ||
1605 cluster_time > mkv->cluster_time_limit ||
1606 (codec_type == AVMEDIA_TYPE_VIDEO && keyframe &&
1607 cluster_size > 4 * 1024))) {
1608 av_log(s, AV_LOG_DEBUG, "Starting new cluster at offset %" PRIu64
1609 " bytes, pts %" PRIu64 "dts %" PRIu64 "\n",
1610 avio_tell(pb), pkt->pts, pkt->dts);
1611 end_ebml_master(pb, mkv->cluster);
1612 mkv->cluster_pos = -1;
1614 mkv_flush_dynbuf(s);
1618 // check if we have an audio packet cached
1619 if (mkv->cur_audio_pkt.size > 0) {
1620 ret = mkv_write_packet_internal(s, &mkv->cur_audio_pkt);
1621 av_free_packet(&mkv->cur_audio_pkt);
1623 av_log(s, AV_LOG_ERROR, "Could not write cached audio packet ret:%d\n", ret);
1628 // buffer an audio packet to ensure the packet containing the video
1629 // keyframe's timecode is contained in the same cluster for WebM
1630 if (codec_type == AVMEDIA_TYPE_AUDIO) {
1631 mkv->cur_audio_pkt = *pkt;
1633 mkv->cur_audio_pkt.buf = av_buffer_ref(pkt->buf);
1634 ret = mkv->cur_audio_pkt.buf ? 0 : AVERROR(ENOMEM);
1636 ret = av_dup_packet(&mkv->cur_audio_pkt);
1637 if (mkv->cur_audio_pkt.side_data_elems > 0) {
1638 ret = av_copy_packet_side_data(&mkv->cur_audio_pkt, &mkv->cur_audio_pkt);
1641 ret = mkv_write_packet_internal(s, pkt);
1645 static int mkv_write_flush_packet(AVFormatContext *s, AVPacket *pkt)
1647 MatroskaMuxContext *mkv = s->priv_data;
1649 if (s->pb->seekable)
1654 if (mkv->cluster_pos != -1) {
1655 av_log(s, AV_LOG_DEBUG, "Flushing cluster at offset %" PRIu64
1656 " bytes\n", avio_tell(pb));
1657 end_ebml_master(pb, mkv->cluster);
1658 mkv->cluster_pos = -1;
1660 mkv_flush_dynbuf(s);
1665 return mkv_write_packet(s, pkt);
1668 static int mkv_write_trailer(AVFormatContext *s)
1670 MatroskaMuxContext *mkv = s->priv_data;
1671 AVIOContext *pb = s->pb;
1672 int64_t currentpos, cuespos;
1675 // check if we have an audio packet cached
1676 if (mkv->cur_audio_pkt.size > 0) {
1677 ret = mkv_write_packet_internal(s, &mkv->cur_audio_pkt);
1678 av_free_packet(&mkv->cur_audio_pkt);
1680 av_log(s, AV_LOG_ERROR, "Could not write cached audio packet ret:%d\n", ret);
1686 end_ebml_master(mkv->dyn_bc, mkv->cluster);
1687 mkv_flush_dynbuf(s);
1688 } else if (mkv->cluster_pos != -1) {
1689 end_ebml_master(pb, mkv->cluster);
1692 if (mkv->mode != MODE_WEBM) {
1693 ret = mkv_write_chapters(s);
1694 if (ret < 0) return ret;
1698 if (mkv->cues->num_entries) {
1699 if (mkv->reserve_cues_space) {
1702 currentpos = avio_tell(pb);
1703 avio_seek(pb, mkv->cues_pos, SEEK_SET);
1705 cuespos = mkv_write_cues(pb, mkv->cues, mkv->tracks, s->nb_streams);
1706 cues_end = avio_tell(pb);
1707 if (cues_end > cuespos + mkv->reserve_cues_space) {
1708 av_log(s, AV_LOG_ERROR, "Insufficient space reserved for cues: %d "
1709 "(needed: %"PRId64").\n", mkv->reserve_cues_space,
1710 cues_end - cuespos);
1711 return AVERROR(EINVAL);
1714 if (cues_end < cuespos + mkv->reserve_cues_space)
1715 put_ebml_void(pb, mkv->reserve_cues_space - (cues_end - cuespos));
1717 avio_seek(pb, currentpos, SEEK_SET);
1719 cuespos = mkv_write_cues(pb, mkv->cues, mkv->tracks, s->nb_streams);
1722 ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_CUES, cuespos);
1723 if (ret < 0) return ret;
1726 mkv_write_seekhead(pb, mkv->main_seekhead);
1728 // update the duration
1729 av_log(s, AV_LOG_DEBUG, "end duration = %" PRIu64 "\n", mkv->duration);
1730 currentpos = avio_tell(pb);
1731 avio_seek(pb, mkv->duration_offset, SEEK_SET);
1732 put_ebml_float(pb, MATROSKA_ID_DURATION, mkv->duration);
1734 avio_seek(pb, currentpos, SEEK_SET);
1737 end_ebml_master(pb, mkv->segment);
1738 av_freep(&mkv->tracks);
1739 av_freep(&mkv->cues->entries);
1740 av_freep(&mkv->cues);
1745 static int mkv_query_codec(enum AVCodecID codec_id, int std_compliance)
1748 for (i = 0; ff_mkv_codec_tags[i].id != AV_CODEC_ID_NONE; i++)
1749 if (ff_mkv_codec_tags[i].id == codec_id)
1752 if (std_compliance < FF_COMPLIANCE_NORMAL) { // mkv theoretically supports any
1753 enum AVMediaType type = avcodec_get_type(codec_id); // video/audio through VFW/ACM
1754 if (type == AVMEDIA_TYPE_VIDEO || type == AVMEDIA_TYPE_AUDIO)
1761 static const AVCodecTag additional_audio_tags[] = {
1762 { AV_CODEC_ID_ALAC, 0XFFFFFFFF },
1763 { AV_CODEC_ID_EAC3, 0XFFFFFFFF },
1764 { AV_CODEC_ID_MLP, 0xFFFFFFFF },
1765 { AV_CODEC_ID_OPUS, 0xFFFFFFFF },
1766 { AV_CODEC_ID_PCM_S16BE, 0xFFFFFFFF },
1767 { AV_CODEC_ID_PCM_S24BE, 0xFFFFFFFF },
1768 { AV_CODEC_ID_PCM_S32BE, 0xFFFFFFFF },
1769 { AV_CODEC_ID_QDM2, 0xFFFFFFFF },
1770 { AV_CODEC_ID_RA_144, 0xFFFFFFFF },
1771 { AV_CODEC_ID_RA_288, 0xFFFFFFFF },
1772 { AV_CODEC_ID_COOK, 0xFFFFFFFF },
1773 { AV_CODEC_ID_TRUEHD, 0xFFFFFFFF },
1774 { AV_CODEC_ID_NONE, 0xFFFFFFFF }
1777 static const AVCodecTag additional_video_tags[] = {
1778 { AV_CODEC_ID_RV10, 0xFFFFFFFF },
1779 { AV_CODEC_ID_RV20, 0xFFFFFFFF },
1780 { AV_CODEC_ID_RV30, 0xFFFFFFFF },
1781 { AV_CODEC_ID_RV40, 0xFFFFFFFF },
1782 { AV_CODEC_ID_VP9, 0xFFFFFFFF },
1783 { AV_CODEC_ID_NONE, 0xFFFFFFFF }
1786 #define OFFSET(x) offsetof(MatroskaMuxContext, x)
1787 #define FLAGS AV_OPT_FLAG_ENCODING_PARAM
1788 static const AVOption options[] = {
1789 { "reserve_index_space", "Reserve a given amount of space (in bytes) at the beginning of the file for the index (cues).", OFFSET(reserve_cues_space), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, FLAGS },
1790 { "cluster_size_limit", "Store at most the provided amount of bytes in a cluster. ", OFFSET(cluster_size_limit), AV_OPT_TYPE_INT , { .i64 = -1 }, -1, INT_MAX, FLAGS },
1791 { "cluster_time_limit", "Store at most the provided number of milliseconds in a cluster.", OFFSET(cluster_time_limit), AV_OPT_TYPE_INT64, { .i64 = -1 }, -1, INT64_MAX, FLAGS },
1795 #if CONFIG_MATROSKA_MUXER
1796 static const AVClass matroska_class = {
1797 .class_name = "matroska muxer",
1798 .item_name = av_default_item_name,
1800 .version = LIBAVUTIL_VERSION_INT,
1803 AVOutputFormat ff_matroska_muxer = {
1805 .long_name = NULL_IF_CONFIG_SMALL("Matroska"),
1806 .mime_type = "video/x-matroska",
1807 .extensions = "mkv",
1808 .priv_data_size = sizeof(MatroskaMuxContext),
1809 .audio_codec = CONFIG_LIBVORBIS_ENCODER ?
1810 AV_CODEC_ID_VORBIS : AV_CODEC_ID_AC3,
1811 .video_codec = CONFIG_LIBX264_ENCODER ?
1812 AV_CODEC_ID_H264 : AV_CODEC_ID_MPEG4,
1813 .write_header = mkv_write_header,
1814 .write_packet = mkv_write_flush_packet,
1815 .write_trailer = mkv_write_trailer,
1816 .flags = AVFMT_GLOBALHEADER | AVFMT_VARIABLE_FPS |
1817 AVFMT_TS_NONSTRICT | AVFMT_ALLOW_FLUSH,
1818 .codec_tag = (const AVCodecTag* const []){
1819 ff_codec_bmp_tags, ff_codec_wav_tags,
1820 additional_audio_tags, additional_video_tags, 0
1823 .subtitle_codec = AV_CODEC_ID_SSA,
1825 .subtitle_codec = AV_CODEC_ID_ASS,
1827 .query_codec = mkv_query_codec,
1828 .priv_class = &matroska_class,
1832 #if CONFIG_WEBM_MUXER
1833 static const AVClass webm_class = {
1834 .class_name = "webm muxer",
1835 .item_name = av_default_item_name,
1837 .version = LIBAVUTIL_VERSION_INT,
1840 AVOutputFormat ff_webm_muxer = {
1842 .long_name = NULL_IF_CONFIG_SMALL("WebM"),
1843 .mime_type = "video/webm",
1844 .extensions = "webm",
1845 .priv_data_size = sizeof(MatroskaMuxContext),
1846 .audio_codec = AV_CODEC_ID_VORBIS,
1847 .video_codec = AV_CODEC_ID_VP8,
1848 .subtitle_codec = AV_CODEC_ID_WEBVTT,
1849 .write_header = mkv_write_header,
1850 .write_packet = mkv_write_flush_packet,
1851 .write_trailer = mkv_write_trailer,
1852 .flags = AVFMT_GLOBALHEADER | AVFMT_VARIABLE_FPS |
1853 AVFMT_TS_NONSTRICT | AVFMT_ALLOW_FLUSH,
1854 .priv_class = &webm_class,
1858 #if CONFIG_MATROSKA_AUDIO_MUXER
1859 static const AVClass mka_class = {
1860 .class_name = "matroska audio muxer",
1861 .item_name = av_default_item_name,
1863 .version = LIBAVUTIL_VERSION_INT,
1865 AVOutputFormat ff_matroska_audio_muxer = {
1867 .long_name = NULL_IF_CONFIG_SMALL("Matroska Audio"),
1868 .mime_type = "audio/x-matroska",
1869 .extensions = "mka",
1870 .priv_data_size = sizeof(MatroskaMuxContext),
1871 .audio_codec = CONFIG_LIBVORBIS_ENCODER ?
1872 AV_CODEC_ID_VORBIS : AV_CODEC_ID_AC3,
1873 .video_codec = AV_CODEC_ID_NONE,
1874 .write_header = mkv_write_header,
1875 .write_packet = mkv_write_flush_packet,
1876 .write_trailer = mkv_write_trailer,
1877 .flags = AVFMT_GLOBALHEADER | AVFMT_TS_NONSTRICT |
1879 .codec_tag = (const AVCodecTag* const []){
1880 ff_codec_wav_tags, additional_audio_tags, 0
1882 .priv_class = &mka_class,