1/* 2 * Matroska muxer 3 * Copyright (c) 2007 David Conrad 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 "avformat.h" 23#include "riff.h" 24#include "isom.h" 25#include "matroska.h" 26#include "avc.h" 27#include "flacenc.h" 28#include "libavutil/intreadwrite.h" 29#include "libavutil/md5.h" 30#include "libavcodec/xiph.h" 31#include "libavcodec/mpeg4audio.h" 32 33typedef struct ebml_master { 34 int64_t pos; ///< absolute offset in the file where the master's elements start 35 int sizebytes; ///< how many bytes were reserved for the size 36} ebml_master; 37 38typedef struct mkv_seekhead_entry { 39 unsigned int elementid; 40 uint64_t segmentpos; 41} mkv_seekhead_entry; 42 43typedef struct mkv_seekhead { 44 int64_t filepos; 45 int64_t segment_offset; ///< the file offset to the beginning of the segment 46 int reserved_size; ///< -1 if appending to file 47 int max_entries; 48 mkv_seekhead_entry *entries; 49 int num_entries; 50} mkv_seekhead; 51 52typedef struct { 53 uint64_t pts; 54 int tracknum; 55 int64_t cluster_pos; ///< file offset of the cluster containing the block 56} mkv_cuepoint; 57 58typedef struct { 59 int64_t segment_offset; 60 mkv_cuepoint *entries; 61 int num_entries; 62} mkv_cues; 63 64typedef struct { 65 int write_dts; 66} mkv_track; 67 68#define MODE_MATROSKAv2 0x01 69#define MODE_WEBM 0x02 70 71typedef struct MatroskaMuxContext { 72 int mode; 73 ByteIOContext *dyn_bc; 74 ebml_master segment; 75 int64_t segment_offset; 76 int64_t segment_uid; 77 ebml_master cluster; 78 int64_t cluster_pos; ///< file offset of the current cluster 79 int64_t cluster_pts; 80 int64_t duration_offset; 81 int64_t duration; 82 mkv_seekhead *main_seekhead; 83 mkv_seekhead *cluster_seekhead; 84 mkv_cues *cues; 85 mkv_track *tracks; 86 87 struct AVMD5 *md5_ctx; 88} MatroskaMuxContext; 89 90 91/** 2 bytes * 3 for EBML IDs, 3 1-byte EBML lengths, 8 bytes for 64 bit 92 * offset, 4 bytes for target EBML ID */ 93#define MAX_SEEKENTRY_SIZE 21 94 95/** per-cuepoint-track - 3 1-byte EBML IDs, 3 1-byte EBML sizes, 2 96 * 8-byte uint max */ 97#define MAX_CUETRACKPOS_SIZE 22 98 99/** per-cuepoint - 2 1-byte EBML IDs, 2 1-byte EBML sizes, 8-byte uint max */ 100#define MAX_CUEPOINT_SIZE(num_tracks) 12 + MAX_CUETRACKPOS_SIZE*num_tracks 101 102 103static int ebml_id_size(unsigned int id) 104{ 105 return (av_log2(id+1)-1)/7+1; 106} 107 108static void put_ebml_id(ByteIOContext *pb, unsigned int id) 109{ 110 int i = ebml_id_size(id); 111 while (i--) 112 put_byte(pb, id >> (i*8)); 113} 114 115/** 116 * Write an EBML size meaning "unknown size". 117 * 118 * @param bytes The number of bytes the size should occupy (maximum: 8). 119 */ 120static void put_ebml_size_unknown(ByteIOContext *pb, int bytes) 121{ 122 assert(bytes <= 8); 123 put_byte(pb, 0x1ff >> bytes); 124 while (--bytes) 125 put_byte(pb, 0xff); 126} 127 128/** 129 * Calculate how many bytes are needed to represent a given number in EBML. 130 */ 131static int ebml_num_size(uint64_t num) 132{ 133 int bytes = 1; 134 while ((num+1) >> bytes*7) bytes++; 135 return bytes; 136} 137 138/** 139 * Write a number in EBML variable length format. 140 * 141 * @param bytes The number of bytes that need to be used to write the number. 142 * If zero, any number of bytes can be used. 143 */ 144static void put_ebml_num(ByteIOContext *pb, uint64_t num, int bytes) 145{ 146 int i, needed_bytes = ebml_num_size(num); 147 148 // sizes larger than this are currently undefined in EBML 149 assert(num < (1ULL<<56)-1); 150 151 if (bytes == 0) 152 // don't care how many bytes are used, so use the min 153 bytes = needed_bytes; 154 // the bytes needed to write the given size would exceed the bytes 155 // that we need to use, so write unknown size. This shouldn't happen. 156 assert(bytes >= needed_bytes); 157 158 num |= 1ULL << bytes*7; 159 for (i = bytes - 1; i >= 0; i--) 160 put_byte(pb, num >> i*8); 161} 162 163static void put_ebml_uint(ByteIOContext *pb, unsigned int elementid, uint64_t val) 164{ 165 int i, bytes = 1; 166 uint64_t tmp = val; 167 while (tmp>>=8) bytes++; 168 169 put_ebml_id(pb, elementid); 170 put_ebml_num(pb, bytes, 0); 171 for (i = bytes - 1; i >= 0; i--) 172 put_byte(pb, val >> i*8); 173} 174 175static void put_ebml_float(ByteIOContext *pb, unsigned int elementid, double val) 176{ 177 put_ebml_id(pb, elementid); 178 put_ebml_num(pb, 8, 0); 179 put_be64(pb, av_dbl2int(val)); 180} 181 182static void put_ebml_binary(ByteIOContext *pb, unsigned int elementid, 183 const uint8_t *buf, int size) 184{ 185 put_ebml_id(pb, elementid); 186 put_ebml_num(pb, size, 0); 187 put_buffer(pb, buf, size); 188} 189 190static void put_ebml_string(ByteIOContext *pb, unsigned int elementid, const char *str) 191{ 192 put_ebml_binary(pb, elementid, str, strlen(str)); 193} 194 195/** 196 * Writes a void element of a given size. Useful for reserving space in 197 * the file to be written to later. 198 * 199 * @param size The number of bytes to reserve, which must be at least 2. 200 */ 201static void put_ebml_void(ByteIOContext *pb, uint64_t size) 202{ 203 int64_t currentpos = url_ftell(pb); 204 205 assert(size >= 2); 206 207 put_ebml_id(pb, EBML_ID_VOID); 208 // we need to subtract the length needed to store the size from the 209 // size we need to reserve so 2 cases, we use 8 bytes to store the 210 // size if possible, 1 byte otherwise 211 if (size < 10) 212 put_ebml_num(pb, size-1, 0); 213 else 214 put_ebml_num(pb, size-9, 8); 215 while(url_ftell(pb) < currentpos + size) 216 put_byte(pb, 0); 217} 218 219static ebml_master start_ebml_master(ByteIOContext *pb, unsigned int elementid, uint64_t expectedsize) 220{ 221 int bytes = expectedsize ? ebml_num_size(expectedsize) : 8; 222 put_ebml_id(pb, elementid); 223 put_ebml_size_unknown(pb, bytes); 224 return (ebml_master){ url_ftell(pb), bytes }; 225} 226 227static void end_ebml_master(ByteIOContext *pb, ebml_master master) 228{ 229 int64_t pos = url_ftell(pb); 230 231 if (url_fseek(pb, master.pos - master.sizebytes, SEEK_SET) < 0) 232 return; 233 put_ebml_num(pb, pos - master.pos, master.sizebytes); 234 url_fseek(pb, pos, SEEK_SET); 235} 236 237static void put_xiph_size(ByteIOContext *pb, int size) 238{ 239 int i; 240 for (i = 0; i < size / 255; i++) 241 put_byte(pb, 255); 242 put_byte(pb, size % 255); 243} 244 245/** 246 * Initialize a mkv_seekhead element to be ready to index level 1 Matroska 247 * elements. If a maximum number of elements is specified, enough space 248 * will be reserved at the current file location to write a seek head of 249 * that size. 250 * 251 * @param segment_offset The absolute offset to the position in the file 252 * where the segment begins. 253 * @param numelements The maximum number of elements that will be indexed 254 * by this seek head, 0 if unlimited. 255 */ 256static mkv_seekhead * mkv_start_seekhead(ByteIOContext *pb, int64_t segment_offset, int numelements) 257{ 258 mkv_seekhead *new_seekhead = av_mallocz(sizeof(mkv_seekhead)); 259 if (new_seekhead == NULL) 260 return NULL; 261 262 new_seekhead->segment_offset = segment_offset; 263 264 if (numelements > 0) { 265 new_seekhead->filepos = url_ftell(pb); 266 // 21 bytes max for a seek entry, 10 bytes max for the SeekHead ID 267 // and size, and 3 bytes to guarantee that an EBML void element 268 // will fit afterwards 269 new_seekhead->reserved_size = numelements * MAX_SEEKENTRY_SIZE + 13; 270 new_seekhead->max_entries = numelements; 271 put_ebml_void(pb, new_seekhead->reserved_size); 272 } 273 return new_seekhead; 274} 275 276static int mkv_add_seekhead_entry(mkv_seekhead *seekhead, unsigned int elementid, uint64_t filepos) 277{ 278 mkv_seekhead_entry *entries = seekhead->entries; 279 280 // don't store more elements than we reserved space for 281 if (seekhead->max_entries > 0 && seekhead->max_entries <= seekhead->num_entries) 282 return -1; 283 284 entries = av_realloc(entries, (seekhead->num_entries + 1) * sizeof(mkv_seekhead_entry)); 285 if (entries == NULL) 286 return AVERROR(ENOMEM); 287 288 entries[seekhead->num_entries ].elementid = elementid; 289 entries[seekhead->num_entries++].segmentpos = filepos - seekhead->segment_offset; 290 291 seekhead->entries = entries; 292 return 0; 293} 294 295/** 296 * Write the seek head to the file and free it. If a maximum number of 297 * elements was specified to mkv_start_seekhead(), the seek head will 298 * be written at the location reserved for it. Otherwise, it is written 299 * at the current location in the file. 300 * 301 * @return The file offset where the seekhead was written, 302 * -1 if an error occurred. 303 */ 304static int64_t mkv_write_seekhead(ByteIOContext *pb, mkv_seekhead *seekhead) 305{ 306 ebml_master metaseek, seekentry; 307 int64_t currentpos; 308 int i; 309 310 currentpos = url_ftell(pb); 311 312 if (seekhead->reserved_size > 0) 313 if (url_fseek(pb, seekhead->filepos, SEEK_SET) < 0) 314 return -1; 315 316 metaseek = start_ebml_master(pb, MATROSKA_ID_SEEKHEAD, seekhead->reserved_size); 317 for (i = 0; i < seekhead->num_entries; i++) { 318 mkv_seekhead_entry *entry = &seekhead->entries[i]; 319 320 seekentry = start_ebml_master(pb, MATROSKA_ID_SEEKENTRY, MAX_SEEKENTRY_SIZE); 321 322 put_ebml_id(pb, MATROSKA_ID_SEEKID); 323 put_ebml_num(pb, ebml_id_size(entry->elementid), 0); 324 put_ebml_id(pb, entry->elementid); 325 326 put_ebml_uint(pb, MATROSKA_ID_SEEKPOSITION, entry->segmentpos); 327 end_ebml_master(pb, seekentry); 328 } 329 end_ebml_master(pb, metaseek); 330 331 if (seekhead->reserved_size > 0) { 332 uint64_t remaining = seekhead->filepos + seekhead->reserved_size - url_ftell(pb); 333 put_ebml_void(pb, remaining); 334 url_fseek(pb, currentpos, SEEK_SET); 335 336 currentpos = seekhead->filepos; 337 } 338 av_free(seekhead->entries); 339 av_free(seekhead); 340 341 return currentpos; 342} 343 344static mkv_cues * mkv_start_cues(int64_t segment_offset) 345{ 346 mkv_cues *cues = av_mallocz(sizeof(mkv_cues)); 347 if (cues == NULL) 348 return NULL; 349 350 cues->segment_offset = segment_offset; 351 return cues; 352} 353 354static int mkv_add_cuepoint(mkv_cues *cues, int stream, int64_t ts, int64_t cluster_pos) 355{ 356 mkv_cuepoint *entries = cues->entries; 357 358 entries = av_realloc(entries, (cues->num_entries + 1) * sizeof(mkv_cuepoint)); 359 if (entries == NULL) 360 return AVERROR(ENOMEM); 361 362 if (ts < 0) 363 return 0; 364 365 entries[cues->num_entries ].pts = ts; 366 entries[cues->num_entries ].tracknum = stream + 1; 367 entries[cues->num_entries++].cluster_pos = cluster_pos - cues->segment_offset; 368 369 cues->entries = entries; 370 return 0; 371} 372 373static int64_t mkv_write_cues(ByteIOContext *pb, mkv_cues *cues, int num_tracks) 374{ 375 ebml_master cues_element; 376 int64_t currentpos; 377 int i, j; 378 379 currentpos = url_ftell(pb); 380 cues_element = start_ebml_master(pb, MATROSKA_ID_CUES, 0); 381 382 for (i = 0; i < cues->num_entries; i++) { 383 ebml_master cuepoint, track_positions; 384 mkv_cuepoint *entry = &cues->entries[i]; 385 uint64_t pts = entry->pts; 386 387 cuepoint = start_ebml_master(pb, MATROSKA_ID_POINTENTRY, MAX_CUEPOINT_SIZE(num_tracks)); 388 put_ebml_uint(pb, MATROSKA_ID_CUETIME, pts); 389 390 // put all the entries from different tracks that have the exact same 391 // timestamp into the same CuePoint 392 for (j = 0; j < cues->num_entries - i && entry[j].pts == pts; j++) { 393 track_positions = start_ebml_master(pb, MATROSKA_ID_CUETRACKPOSITION, MAX_CUETRACKPOS_SIZE); 394 put_ebml_uint(pb, MATROSKA_ID_CUETRACK , entry[j].tracknum ); 395 put_ebml_uint(pb, MATROSKA_ID_CUECLUSTERPOSITION, entry[j].cluster_pos); 396 end_ebml_master(pb, track_positions); 397 } 398 i += j - 1; 399 end_ebml_master(pb, cuepoint); 400 } 401 end_ebml_master(pb, cues_element); 402 403 av_free(cues->entries); 404 av_free(cues); 405 return currentpos; 406} 407 408static int put_xiph_codecpriv(AVFormatContext *s, ByteIOContext *pb, AVCodecContext *codec) 409{ 410 uint8_t *header_start[3]; 411 int header_len[3]; 412 int first_header_size; 413 int j; 414 415 if (codec->codec_id == CODEC_ID_VORBIS) 416 first_header_size = 30; 417 else 418 first_header_size = 42; 419 420 if (ff_split_xiph_headers(codec->extradata, codec->extradata_size, 421 first_header_size, header_start, header_len) < 0) { 422 av_log(s, AV_LOG_ERROR, "Extradata corrupt.\n"); 423 return -1; 424 } 425 426 put_byte(pb, 2); // number packets - 1 427 for (j = 0; j < 2; j++) { 428 put_xiph_size(pb, header_len[j]); 429 } 430 for (j = 0; j < 3; j++) 431 put_buffer(pb, header_start[j], header_len[j]); 432 433 return 0; 434} 435 436static void get_aac_sample_rates(AVFormatContext *s, AVCodecContext *codec, int *sample_rate, int *output_sample_rate) 437{ 438 int sri; 439 440 if (codec->extradata_size < 2) { 441 av_log(s, AV_LOG_WARNING, "No AAC extradata, unable to determine samplerate.\n"); 442 return; 443 } 444 445 sri = ((codec->extradata[0] << 1) & 0xE) | (codec->extradata[1] >> 7); 446 if (sri > 12) { 447 av_log(s, AV_LOG_WARNING, "AAC samplerate index out of bounds\n"); 448 return; 449 } 450 *sample_rate = ff_mpeg4audio_sample_rates[sri]; 451 452 // if sbr, get output sample rate as well 453 if (codec->extradata_size == 5) { 454 sri = (codec->extradata[4] >> 3) & 0xF; 455 if (sri > 12) { 456 av_log(s, AV_LOG_WARNING, "AAC output samplerate index out of bounds\n"); 457 return; 458 } 459 *output_sample_rate = ff_mpeg4audio_sample_rates[sri]; 460 } 461} 462 463static int mkv_write_codecprivate(AVFormatContext *s, ByteIOContext *pb, AVCodecContext *codec, int native_id, int qt_id) 464{ 465 ByteIOContext *dyn_cp; 466 uint8_t *codecpriv; 467 int ret, codecpriv_size; 468 469 ret = url_open_dyn_buf(&dyn_cp); 470 if(ret < 0) 471 return ret; 472 473 if (native_id) { 474 if (codec->codec_id == CODEC_ID_VORBIS || codec->codec_id == CODEC_ID_THEORA) 475 ret = put_xiph_codecpriv(s, dyn_cp, codec); 476 else if (codec->codec_id == CODEC_ID_FLAC) 477 ret = ff_flac_write_header(dyn_cp, codec, 1); 478 else if (codec->codec_id == CODEC_ID_H264) 479 ret = ff_isom_write_avcc(dyn_cp, codec->extradata, codec->extradata_size); 480 else if (codec->extradata_size) 481 put_buffer(dyn_cp, codec->extradata, codec->extradata_size); 482 } else if (codec->codec_type == AVMEDIA_TYPE_VIDEO) { 483 if (qt_id) { 484 if (!codec->codec_tag) 485 codec->codec_tag = ff_codec_get_tag(codec_movvideo_tags, codec->codec_id); 486 if (codec->extradata_size) 487 put_buffer(dyn_cp, codec->extradata, codec->extradata_size); 488 } else { 489 if (!codec->codec_tag) 490 codec->codec_tag = ff_codec_get_tag(ff_codec_bmp_tags, codec->codec_id); 491 if (!codec->codec_tag) { 492 av_log(s, AV_LOG_ERROR, "No bmp codec ID found.\n"); 493 ret = -1; 494 } 495 496 ff_put_bmp_header(dyn_cp, codec, ff_codec_bmp_tags, 0); 497 } 498 499 } else if (codec->codec_type == AVMEDIA_TYPE_AUDIO) { 500 unsigned int tag; 501 tag = ff_codec_get_tag(ff_codec_wav_tags, codec->codec_id); 502 if (!tag) { 503 av_log(s, AV_LOG_ERROR, "No wav codec ID found.\n"); 504 ret = -1; 505 } 506 if (!codec->codec_tag) 507 codec->codec_tag = tag; 508 509 ff_put_wav_header(dyn_cp, codec); 510 } 511 512 codecpriv_size = url_close_dyn_buf(dyn_cp, &codecpriv); 513 if (codecpriv_size) 514 put_ebml_binary(pb, MATROSKA_ID_CODECPRIVATE, codecpriv, codecpriv_size); 515 av_free(codecpriv); 516 return ret; 517} 518 519static int mkv_write_tracks(AVFormatContext *s) 520{ 521 MatroskaMuxContext *mkv = s->priv_data; 522 ByteIOContext *pb = s->pb; 523 ebml_master tracks; 524 int i, j, ret; 525 526 ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_TRACKS, url_ftell(pb)); 527 if (ret < 0) return ret; 528 529 tracks = start_ebml_master(pb, MATROSKA_ID_TRACKS, 0); 530 for (i = 0; i < s->nb_streams; i++) { 531 AVStream *st = s->streams[i]; 532 AVCodecContext *codec = st->codec; 533 ebml_master subinfo, track; 534 int native_id = 0; 535 int qt_id = 0; 536 int bit_depth = av_get_bits_per_sample(codec->codec_id); 537 int sample_rate = codec->sample_rate; 538 int output_sample_rate = 0; 539 AVMetadataTag *tag; 540 541 if (!bit_depth) 542 bit_depth = av_get_bits_per_sample_format(codec->sample_fmt); 543 544 if (codec->codec_id == CODEC_ID_AAC) 545 get_aac_sample_rates(s, codec, &sample_rate, &output_sample_rate); 546 547 track = start_ebml_master(pb, MATROSKA_ID_TRACKENTRY, 0); 548 put_ebml_uint (pb, MATROSKA_ID_TRACKNUMBER , i + 1); 549 put_ebml_uint (pb, MATROSKA_ID_TRACKUID , i + 1); 550 put_ebml_uint (pb, MATROSKA_ID_TRACKFLAGLACING , 0); // no lacing (yet) 551 552 if ((tag = av_metadata_get(st->metadata, "title", NULL, 0))) 553 put_ebml_string(pb, MATROSKA_ID_TRACKNAME, tag->value); 554 tag = av_metadata_get(st->metadata, "language", NULL, 0); 555 put_ebml_string(pb, MATROSKA_ID_TRACKLANGUAGE, tag ? tag->value:"und"); 556 557 if (st->disposition) 558 put_ebml_uint(pb, MATROSKA_ID_TRACKFLAGDEFAULT, !!(st->disposition & AV_DISPOSITION_DEFAULT)); 559 560 // look for a codec ID string specific to mkv to use, 561 // if none are found, use AVI codes 562 for (j = 0; ff_mkv_codec_tags[j].id != CODEC_ID_NONE; j++) { 563 if (ff_mkv_codec_tags[j].id == codec->codec_id) { 564 put_ebml_string(pb, MATROSKA_ID_CODECID, ff_mkv_codec_tags[j].str); 565 native_id = 1; 566 break; 567 } 568 } 569 570 if (mkv->mode == MODE_WEBM && !(codec->codec_id == CODEC_ID_VP8 || 571 codec->codec_id == CODEC_ID_VORBIS)) { 572 av_log(s, AV_LOG_ERROR, 573 "Only VP8 video and Vorbis audio are supported for WebM.\n"); 574 return AVERROR(EINVAL); 575 } 576 577 switch (codec->codec_type) { 578 case AVMEDIA_TYPE_VIDEO: 579 put_ebml_uint(pb, MATROSKA_ID_TRACKTYPE, MATROSKA_TRACK_TYPE_VIDEO); 580 put_ebml_uint(pb, MATROSKA_ID_TRACKDEFAULTDURATION, av_q2d(codec->time_base)*1E9); 581 582 if (!native_id && 583 ff_codec_get_tag(codec_movvideo_tags, codec->codec_id) && 584 (!ff_codec_get_tag(ff_codec_bmp_tags, codec->codec_id) 585 || codec->codec_id == CODEC_ID_SVQ1 586 || codec->codec_id == CODEC_ID_SVQ3 587 || codec->codec_id == CODEC_ID_CINEPAK)) 588 qt_id = 1; 589 590 if (qt_id) 591 put_ebml_string(pb, MATROSKA_ID_CODECID, "V_QUICKTIME"); 592 else if (!native_id) { 593 // if there is no mkv-specific codec ID, use VFW mode 594 put_ebml_string(pb, MATROSKA_ID_CODECID, "V_MS/VFW/FOURCC"); 595 mkv->tracks[i].write_dts = 1; 596 } 597 598 subinfo = start_ebml_master(pb, MATROSKA_ID_TRACKVIDEO, 0); 599 // XXX: interlace flag? 600 put_ebml_uint (pb, MATROSKA_ID_VIDEOPIXELWIDTH , codec->width); 601 put_ebml_uint (pb, MATROSKA_ID_VIDEOPIXELHEIGHT, codec->height); 602 if (st->sample_aspect_ratio.num) { 603 int d_width = codec->width*av_q2d(st->sample_aspect_ratio); 604 put_ebml_uint(pb, MATROSKA_ID_VIDEODISPLAYWIDTH , d_width); 605 put_ebml_uint(pb, MATROSKA_ID_VIDEODISPLAYHEIGHT, codec->height); 606 } 607 end_ebml_master(pb, subinfo); 608 break; 609 610 case AVMEDIA_TYPE_AUDIO: 611 put_ebml_uint(pb, MATROSKA_ID_TRACKTYPE, MATROSKA_TRACK_TYPE_AUDIO); 612 613 if (!native_id) 614 // no mkv-specific ID, use ACM mode 615 put_ebml_string(pb, MATROSKA_ID_CODECID, "A_MS/ACM"); 616 617 subinfo = start_ebml_master(pb, MATROSKA_ID_TRACKAUDIO, 0); 618 put_ebml_uint (pb, MATROSKA_ID_AUDIOCHANNELS , codec->channels); 619 put_ebml_float (pb, MATROSKA_ID_AUDIOSAMPLINGFREQ, sample_rate); 620 if (output_sample_rate) 621 put_ebml_float(pb, MATROSKA_ID_AUDIOOUTSAMPLINGFREQ, output_sample_rate); 622 if (bit_depth) 623 put_ebml_uint(pb, MATROSKA_ID_AUDIOBITDEPTH, bit_depth); 624 end_ebml_master(pb, subinfo); 625 break; 626 627 case AVMEDIA_TYPE_SUBTITLE: 628 put_ebml_uint(pb, MATROSKA_ID_TRACKTYPE, MATROSKA_TRACK_TYPE_SUBTITLE); 629 break; 630 default: 631 av_log(s, AV_LOG_ERROR, "Only audio, video, and subtitles are supported for Matroska."); 632 break; 633 } 634 ret = mkv_write_codecprivate(s, pb, codec, native_id, qt_id); 635 if (ret < 0) return ret; 636 637 end_ebml_master(pb, track); 638 639 // ms precision is the de-facto standard timescale for mkv files 640 av_set_pts_info(st, 64, 1, 1000); 641 } 642 end_ebml_master(pb, tracks); 643 return 0; 644} 645 646static int mkv_write_chapters(AVFormatContext *s) 647{ 648 MatroskaMuxContext *mkv = s->priv_data; 649 ByteIOContext *pb = s->pb; 650 ebml_master chapters, editionentry; 651 AVRational scale = {1, 1E9}; 652 int i, ret; 653 654 if (!s->nb_chapters) 655 return 0; 656 657 ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_CHAPTERS, url_ftell(pb)); 658 if (ret < 0) return ret; 659 660 chapters = start_ebml_master(pb, MATROSKA_ID_CHAPTERS , 0); 661 editionentry = start_ebml_master(pb, MATROSKA_ID_EDITIONENTRY, 0); 662 put_ebml_uint(pb, MATROSKA_ID_EDITIONFLAGDEFAULT, 1); 663 put_ebml_uint(pb, MATROSKA_ID_EDITIONFLAGHIDDEN , 0); 664 for (i = 0; i < s->nb_chapters; i++) { 665 ebml_master chapteratom, chapterdisplay; 666 AVChapter *c = s->chapters[i]; 667 AVMetadataTag *t = NULL; 668 669 chapteratom = start_ebml_master(pb, MATROSKA_ID_CHAPTERATOM, 0); 670 put_ebml_uint(pb, MATROSKA_ID_CHAPTERUID, c->id); 671 put_ebml_uint(pb, MATROSKA_ID_CHAPTERTIMESTART, 672 av_rescale_q(c->start, c->time_base, scale)); 673 put_ebml_uint(pb, MATROSKA_ID_CHAPTERTIMEEND, 674 av_rescale_q(c->end, c->time_base, scale)); 675 put_ebml_uint(pb, MATROSKA_ID_CHAPTERFLAGHIDDEN , 0); 676 put_ebml_uint(pb, MATROSKA_ID_CHAPTERFLAGENABLED, 1); 677 if ((t = av_metadata_get(c->metadata, "title", NULL, 0))) { 678 chapterdisplay = start_ebml_master(pb, MATROSKA_ID_CHAPTERDISPLAY, 0); 679 put_ebml_string(pb, MATROSKA_ID_CHAPSTRING, t->value); 680 put_ebml_string(pb, MATROSKA_ID_CHAPLANG , "und"); 681 end_ebml_master(pb, chapterdisplay); 682 } 683 end_ebml_master(pb, chapteratom); 684 } 685 end_ebml_master(pb, editionentry); 686 end_ebml_master(pb, chapters); 687 return 0; 688} 689 690static int mkv_write_header(AVFormatContext *s) 691{ 692 MatroskaMuxContext *mkv = s->priv_data; 693 ByteIOContext *pb = s->pb; 694 ebml_master ebml_header, segment_info; 695 AVMetadataTag *tag; 696 int ret; 697 698 if (!strcmp(s->oformat->name, "webm")) mkv->mode = MODE_WEBM; 699 else mkv->mode = MODE_MATROSKAv2; 700 701 mkv->md5_ctx = av_mallocz(av_md5_size); 702 av_md5_init(mkv->md5_ctx); 703 mkv->tracks = av_mallocz(s->nb_streams * sizeof(*mkv->tracks)); 704 705 ebml_header = start_ebml_master(pb, EBML_ID_HEADER, 0); 706 put_ebml_uint (pb, EBML_ID_EBMLVERSION , 1); 707 put_ebml_uint (pb, EBML_ID_EBMLREADVERSION , 1); 708 put_ebml_uint (pb, EBML_ID_EBMLMAXIDLENGTH , 4); 709 put_ebml_uint (pb, EBML_ID_EBMLMAXSIZELENGTH , 8); 710 put_ebml_string (pb, EBML_ID_DOCTYPE , s->oformat->name); 711 put_ebml_uint (pb, EBML_ID_DOCTYPEVERSION , 2); 712 put_ebml_uint (pb, EBML_ID_DOCTYPEREADVERSION , 2); 713 end_ebml_master(pb, ebml_header); 714 715 mkv->segment = start_ebml_master(pb, MATROSKA_ID_SEGMENT, 0); 716 mkv->segment_offset = url_ftell(pb); 717 718 // we write 2 seek heads - one at the end of the file to point to each 719 // cluster, and one at the beginning to point to all other level one 720 // elements (including the seek head at the end of the file), which 721 // isn't more than 10 elements if we only write one of each other 722 // currently defined level 1 element 723 mkv->main_seekhead = mkv_start_seekhead(pb, mkv->segment_offset, 10); 724 mkv->cluster_seekhead = mkv_start_seekhead(pb, mkv->segment_offset, 0); 725 if (mkv->main_seekhead == NULL || mkv->cluster_seekhead == NULL) 726 return AVERROR(ENOMEM); 727 728 ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_INFO, url_ftell(pb)); 729 if (ret < 0) return ret; 730 731 segment_info = start_ebml_master(pb, MATROSKA_ID_INFO, 0); 732 put_ebml_uint(pb, MATROSKA_ID_TIMECODESCALE, 1000000); 733 if ((tag = av_metadata_get(s->metadata, "title", NULL, 0))) 734 put_ebml_string(pb, MATROSKA_ID_TITLE, tag->value); 735 if (!(s->streams[0]->codec->flags & CODEC_FLAG_BITEXACT)) { 736 put_ebml_string(pb, MATROSKA_ID_MUXINGAPP , LIBAVFORMAT_IDENT); 737 put_ebml_string(pb, MATROSKA_ID_WRITINGAPP, LIBAVFORMAT_IDENT); 738 739 // reserve space to write the segment UID later 740 mkv->segment_uid = url_ftell(pb); 741 put_ebml_void(pb, 19); 742 } 743 744 // reserve space for the duration 745 mkv->duration = 0; 746 mkv->duration_offset = url_ftell(pb); 747 put_ebml_void(pb, 11); // assumes double-precision float to be written 748 end_ebml_master(pb, segment_info); 749 750 ret = mkv_write_tracks(s); 751 if (ret < 0) return ret; 752 753 if (mkv->mode != MODE_WEBM) { 754 ret = mkv_write_chapters(s); 755 if (ret < 0) return ret; 756 } 757 758 if (url_is_streamed(s->pb)) 759 mkv_write_seekhead(pb, mkv->main_seekhead); 760 761 mkv->cues = mkv_start_cues(mkv->segment_offset); 762 if (mkv->cues == NULL) 763 return AVERROR(ENOMEM); 764 765 put_flush_packet(pb); 766 return 0; 767} 768 769static int mkv_blockgroup_size(int pkt_size) 770{ 771 int size = pkt_size + 4; 772 size += ebml_num_size(size); 773 size += 2; // EBML ID for block and block duration 774 size += 8; // max size of block duration 775 size += ebml_num_size(size); 776 size += 1; // blockgroup EBML ID 777 return size; 778} 779 780static int ass_get_duration(const uint8_t *p) 781{ 782 int sh, sm, ss, sc, eh, em, es, ec; 783 uint64_t start, end; 784 785 if (sscanf(p, "%*[^,],%d:%d:%d%*c%d,%d:%d:%d%*c%d", 786 &sh, &sm, &ss, &sc, &eh, &em, &es, &ec) != 8) 787 return 0; 788 start = 3600000*sh + 60000*sm + 1000*ss + 10*sc; 789 end = 3600000*eh + 60000*em + 1000*es + 10*ec; 790 return end - start; 791} 792 793static int mkv_write_ass_blocks(AVFormatContext *s, ByteIOContext *pb, AVPacket *pkt) 794{ 795 MatroskaMuxContext *mkv = s->priv_data; 796 int i, layer = 0, max_duration = 0, size, line_size, data_size = pkt->size; 797 uint8_t *start, *end, *data = pkt->data; 798 ebml_master blockgroup; 799 char buffer[2048]; 800 801 while (data_size) { 802 int duration = ass_get_duration(data); 803 max_duration = FFMAX(duration, max_duration); 804 end = memchr(data, '\n', data_size); 805 size = line_size = end ? end-data+1 : data_size; 806 size -= end ? (end[-1]=='\r')+1 : 0; 807 start = data; 808 for (i=0; i<3; i++, start++) 809 if (!(start = memchr(start, ',', size-(start-data)))) 810 return max_duration; 811 size -= start - data; 812 sscanf(data, "Dialogue: %d,", &layer); 813 i = snprintf(buffer, sizeof(buffer), "%"PRId64",%d,", 814 s->streams[pkt->stream_index]->nb_frames++, layer); 815 size = FFMIN(i+size, sizeof(buffer)); 816 memcpy(buffer+i, start, size-i); 817 818 av_log(s, AV_LOG_DEBUG, "Writing block at offset %" PRIu64 ", size %d, " 819 "pts %" PRId64 ", duration %d\n", 820 url_ftell(pb), size, pkt->pts, duration); 821 blockgroup = start_ebml_master(pb, MATROSKA_ID_BLOCKGROUP, mkv_blockgroup_size(size)); 822 put_ebml_id(pb, MATROSKA_ID_BLOCK); 823 put_ebml_num(pb, size+4, 0); 824 put_byte(pb, 0x80 | (pkt->stream_index + 1)); // this assumes stream_index is less than 126 825 put_be16(pb, pkt->pts - mkv->cluster_pts); 826 put_byte(pb, 0); 827 put_buffer(pb, buffer, size); 828 put_ebml_uint(pb, MATROSKA_ID_BLOCKDURATION, duration); 829 end_ebml_master(pb, blockgroup); 830 831 data += line_size; 832 data_size -= line_size; 833 } 834 835 return max_duration; 836} 837 838static void mkv_write_block(AVFormatContext *s, ByteIOContext *pb, 839 unsigned int blockid, AVPacket *pkt, int flags) 840{ 841 MatroskaMuxContext *mkv = s->priv_data; 842 AVCodecContext *codec = s->streams[pkt->stream_index]->codec; 843 uint8_t *data = NULL; 844 int size = pkt->size; 845 int64_t ts = mkv->tracks[pkt->stream_index].write_dts ? pkt->dts : pkt->pts; 846 847 av_log(s, AV_LOG_DEBUG, "Writing block at offset %" PRIu64 ", size %d, " 848 "pts %" PRId64 ", dts %" PRId64 ", duration %d, flags %d\n", 849 url_ftell(pb), pkt->size, pkt->pts, pkt->dts, pkt->duration, flags); 850 if (codec->codec_id == CODEC_ID_H264 && codec->extradata_size > 0 && 851 (AV_RB24(codec->extradata) == 1 || AV_RB32(codec->extradata) == 1)) 852 ff_avc_parse_nal_units_buf(pkt->data, &data, &size); 853 else 854 data = pkt->data; 855 put_ebml_id(pb, blockid); 856 put_ebml_num(pb, size+4, 0); 857 put_byte(pb, 0x80 | (pkt->stream_index + 1)); // this assumes stream_index is less than 126 858 put_be16(pb, ts - mkv->cluster_pts); 859 put_byte(pb, flags); 860 put_buffer(pb, data, size); 861 if (data != pkt->data) 862 av_free(data); 863} 864 865static void mkv_flush_dynbuf(AVFormatContext *s) 866{ 867 MatroskaMuxContext *mkv = s->priv_data; 868 int bufsize; 869 uint8_t *dyn_buf; 870 871 if (!mkv->dyn_bc) 872 return; 873 874 bufsize = url_close_dyn_buf(mkv->dyn_bc, &dyn_buf); 875 put_buffer(s->pb, dyn_buf, bufsize); 876 av_free(dyn_buf); 877 mkv->dyn_bc = NULL; 878} 879 880static int mkv_write_packet(AVFormatContext *s, AVPacket *pkt) 881{ 882 MatroskaMuxContext *mkv = s->priv_data; 883 ByteIOContext *pb = s->pb; 884 AVCodecContext *codec = s->streams[pkt->stream_index]->codec; 885 int keyframe = !!(pkt->flags & AV_PKT_FLAG_KEY); 886 int duration = pkt->duration; 887 int ret; 888 int64_t ts = mkv->tracks[pkt->stream_index].write_dts ? pkt->dts : pkt->pts; 889 890 if (ts == AV_NOPTS_VALUE) { 891 av_log(s, AV_LOG_ERROR, "Can't write packet with unknown timestamp\n"); 892 return AVERROR(EINVAL); 893 } 894 895 if (url_is_streamed(s->pb)) { 896 if (!mkv->dyn_bc) 897 url_open_dyn_buf(&mkv->dyn_bc); 898 pb = mkv->dyn_bc; 899 } 900 901 if (!mkv->cluster_pos) { 902 ret = mkv_add_seekhead_entry(mkv->cluster_seekhead, MATROSKA_ID_CLUSTER, url_ftell(pb)); 903 if (ret < 0) return ret; 904 905 mkv->cluster_pos = url_ftell(s->pb); 906 mkv->cluster = start_ebml_master(pb, MATROSKA_ID_CLUSTER, 0); 907 put_ebml_uint(pb, MATROSKA_ID_CLUSTERTIMECODE, FFMAX(0, ts)); 908 mkv->cluster_pts = FFMAX(0, ts); 909 av_md5_update(mkv->md5_ctx, pkt->data, FFMIN(200, pkt->size)); 910 } 911 912 if (codec->codec_type != AVMEDIA_TYPE_SUBTITLE) { 913 mkv_write_block(s, pb, MATROSKA_ID_SIMPLEBLOCK, pkt, keyframe << 7); 914 } else if (codec->codec_id == CODEC_ID_SSA) { 915 duration = mkv_write_ass_blocks(s, pb, pkt); 916 } else { 917 ebml_master blockgroup = start_ebml_master(pb, MATROSKA_ID_BLOCKGROUP, mkv_blockgroup_size(pkt->size)); 918 duration = pkt->convergence_duration; 919 mkv_write_block(s, pb, MATROSKA_ID_BLOCK, pkt, 0); 920 put_ebml_uint(pb, MATROSKA_ID_BLOCKDURATION, duration); 921 end_ebml_master(pb, blockgroup); 922 } 923 924 if (codec->codec_type == AVMEDIA_TYPE_VIDEO && keyframe) { 925 ret = mkv_add_cuepoint(mkv->cues, pkt->stream_index, ts, mkv->cluster_pos); 926 if (ret < 0) return ret; 927 } 928 929 // start a new cluster every 5 MB or 5 sec, or 32k / 1 sec for streaming 930 if ((url_is_streamed(s->pb) && (url_ftell(pb) > 32*1024 || ts > mkv->cluster_pts + 1000)) 931 || url_ftell(pb) > mkv->cluster_pos + 5*1024*1024 || ts > mkv->cluster_pts + 5000) { 932 av_log(s, AV_LOG_DEBUG, "Starting new cluster at offset %" PRIu64 933 " bytes, pts %" PRIu64 "\n", url_ftell(pb), ts); 934 end_ebml_master(pb, mkv->cluster); 935 mkv->cluster_pos = 0; 936 if (mkv->dyn_bc) 937 mkv_flush_dynbuf(s); 938 } 939 940 mkv->duration = FFMAX(mkv->duration, ts + duration); 941 return 0; 942} 943 944static int mkv_write_trailer(AVFormatContext *s) 945{ 946 MatroskaMuxContext *mkv = s->priv_data; 947 ByteIOContext *pb = s->pb; 948 int64_t currentpos, second_seekhead, cuespos; 949 int ret; 950 951 if (mkv->dyn_bc) { 952 end_ebml_master(mkv->dyn_bc, mkv->cluster); 953 mkv_flush_dynbuf(s); 954 } else if (mkv->cluster_pos) { 955 end_ebml_master(pb, mkv->cluster); 956 } 957 958 if (!url_is_streamed(pb)) { 959 cuespos = mkv_write_cues(pb, mkv->cues, s->nb_streams); 960 second_seekhead = mkv_write_seekhead(pb, mkv->cluster_seekhead); 961 962 ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_CUES , cuespos); 963 if (ret < 0) return ret; 964 if (second_seekhead >= 0) { 965 ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_SEEKHEAD, second_seekhead); 966 if (ret < 0) return ret; 967 } 968 mkv_write_seekhead(pb, mkv->main_seekhead); 969 970 // update the duration 971 av_log(s, AV_LOG_DEBUG, "end duration = %" PRIu64 "\n", mkv->duration); 972 currentpos = url_ftell(pb); 973 url_fseek(pb, mkv->duration_offset, SEEK_SET); 974 put_ebml_float(pb, MATROSKA_ID_DURATION, mkv->duration); 975 976 // write the md5sum of some frames as the segment UID 977 if (!(s->streams[0]->codec->flags & CODEC_FLAG_BITEXACT)) { 978 uint8_t segment_uid[16]; 979 av_md5_final(mkv->md5_ctx, segment_uid); 980 url_fseek(pb, mkv->segment_uid, SEEK_SET); 981 put_ebml_binary(pb, MATROSKA_ID_SEGMENTUID, segment_uid, 16); 982 } 983 url_fseek(pb, currentpos, SEEK_SET); 984 } 985 986 end_ebml_master(pb, mkv->segment); 987 av_free(mkv->md5_ctx); 988 av_free(mkv->tracks); 989 put_flush_packet(pb); 990 return 0; 991} 992 993#if CONFIG_MATROSKA_MUXER 994AVOutputFormat matroska_muxer = { 995 "matroska", 996 NULL_IF_CONFIG_SMALL("Matroska file format"), 997 "video/x-matroska", 998 "mkv", 999 sizeof(MatroskaMuxContext), 1000 CODEC_ID_MP2, 1001 CODEC_ID_MPEG4, 1002 mkv_write_header, 1003 mkv_write_packet, 1004 mkv_write_trailer, 1005 .flags = AVFMT_GLOBALHEADER | AVFMT_VARIABLE_FPS, 1006 .codec_tag = (const AVCodecTag* const []){ff_codec_bmp_tags, ff_codec_wav_tags, 0}, 1007 .subtitle_codec = CODEC_ID_TEXT, 1008}; 1009#endif 1010 1011#if CONFIG_WEBM_MUXER 1012AVOutputFormat webm_muxer = { 1013 "webm", 1014 NULL_IF_CONFIG_SMALL("WebM file format"), 1015 "video/webm", 1016 "webm", 1017 sizeof(MatroskaMuxContext), 1018 CODEC_ID_VORBIS, 1019 CODEC_ID_VP8, 1020 mkv_write_header, 1021 mkv_write_packet, 1022 mkv_write_trailer, 1023 .flags = AVFMT_GLOBALHEADER | AVFMT_VARIABLE_FPS, 1024}; 1025#endif 1026 1027#if CONFIG_MATROSKA_AUDIO_MUXER 1028AVOutputFormat matroska_audio_muxer = { 1029 "matroska", 1030 NULL_IF_CONFIG_SMALL("Matroska file format"), 1031 "audio/x-matroska", 1032 "mka", 1033 sizeof(MatroskaMuxContext), 1034 CODEC_ID_MP2, 1035 CODEC_ID_NONE, 1036 mkv_write_header, 1037 mkv_write_packet, 1038 mkv_write_trailer, 1039 .flags = AVFMT_GLOBALHEADER, 1040 .codec_tag = (const AVCodecTag* const []){ff_codec_wav_tags, 0}, 1041}; 1042#endif 1043