/* * Matroska muxer * Copyright (c) 2007 David Conrad * * This file is part of FFmpeg. * * FFmpeg is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * FFmpeg is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #include "avformat.h" #include "internal.h" #include "riff.h" #include "isom.h" #include "matroska.h" #include "avc.h" #include "flacenc.h" #include "avlanguage.h" #include "libavutil/samplefmt.h" #include "libavutil/intreadwrite.h" #include "libavutil/intfloat.h" #include "libavutil/mathematics.h" #include "libavutil/random_seed.h" #include "libavutil/lfg.h" #include "libavutil/dict.h" #include "libavutil/avstring.h" #include "libavcodec/xiph.h" #include "libavcodec/mpeg4audio.h" typedef struct ebml_master { int64_t pos; ///< absolute offset in the file where the master's elements start int sizebytes; ///< how many bytes were reserved for the size } ebml_master; typedef struct mkv_seekhead_entry { unsigned int elementid; uint64_t segmentpos; } mkv_seekhead_entry; typedef struct mkv_seekhead { int64_t filepos; int64_t segment_offset; ///< the file offset to the beginning of the segment int reserved_size; ///< -1 if appending to file int max_entries; mkv_seekhead_entry *entries; int num_entries; } mkv_seekhead; typedef struct { uint64_t pts; int tracknum; int64_t cluster_pos; ///< file offset of the cluster containing the block } mkv_cuepoint; typedef struct { int64_t segment_offset; mkv_cuepoint *entries; int num_entries; } mkv_cues; typedef struct { int write_dts; } mkv_track; #define MODE_MATROSKAv2 0x01 #define MODE_WEBM 0x02 typedef struct MatroskaMuxContext { int mode; AVIOContext *dyn_bc; ebml_master segment; int64_t segment_offset; ebml_master cluster; int64_t cluster_pos; ///< file offset of the current cluster int64_t cluster_pts; int64_t duration_offset; int64_t duration; mkv_seekhead *main_seekhead; mkv_cues *cues; mkv_track *tracks; unsigned int audio_buffer_size; AVPacket cur_audio_pkt; int have_attachments; } MatroskaMuxContext; /** 2 bytes * 3 for EBML IDs, 3 1-byte EBML lengths, 8 bytes for 64 bit * offset, 4 bytes for target EBML ID */ #define MAX_SEEKENTRY_SIZE 21 /** per-cuepoint-track - 3 1-byte EBML IDs, 3 1-byte EBML sizes, 2 * 8-byte uint max */ #define MAX_CUETRACKPOS_SIZE 22 /** per-cuepoint - 2 1-byte EBML IDs, 2 1-byte EBML sizes, 8-byte uint max */ #define MAX_CUEPOINT_SIZE(num_tracks) 12 + MAX_CUETRACKPOS_SIZE*num_tracks static int ebml_id_size(unsigned int id) { return (av_log2(id+1)-1)/7+1; } static void put_ebml_id(AVIOContext *pb, unsigned int id) { int i = ebml_id_size(id); while (i--) avio_w8(pb, id >> (i*8)); } /** * Write an EBML size meaning "unknown size". * * @param bytes The number of bytes the size should occupy (maximum: 8). */ static void put_ebml_size_unknown(AVIOContext *pb, int bytes) { assert(bytes <= 8); avio_w8(pb, 0x1ff >> bytes); while (--bytes) avio_w8(pb, 0xff); } /** * Calculate how many bytes are needed to represent a given number in EBML. */ static int ebml_num_size(uint64_t num) { int bytes = 1; while ((num+1) >> bytes*7) bytes++; return bytes; } /** * Write a number in EBML variable length format. * * @param bytes The number of bytes that need to be used to write the number. * If zero, any number of bytes can be used. */ static void put_ebml_num(AVIOContext *pb, uint64_t num, int bytes) { int i, needed_bytes = ebml_num_size(num); // sizes larger than this are currently undefined in EBML assert(num < (1ULL<<56)-1); if (bytes == 0) // don't care how many bytes are used, so use the min bytes = needed_bytes; // the bytes needed to write the given size would exceed the bytes // that we need to use, so write unknown size. This shouldn't happen. assert(bytes >= needed_bytes); num |= 1ULL << bytes*7; for (i = bytes - 1; i >= 0; i--) avio_w8(pb, num >> i*8); } static void put_ebml_uint(AVIOContext *pb, unsigned int elementid, uint64_t val) { int i, bytes = 1; uint64_t tmp = val; while (tmp>>=8) bytes++; put_ebml_id(pb, elementid); put_ebml_num(pb, bytes, 0); for (i = bytes - 1; i >= 0; i--) avio_w8(pb, val >> i*8); } static void put_ebml_float(AVIOContext *pb, unsigned int elementid, double val) { put_ebml_id(pb, elementid); put_ebml_num(pb, 8, 0); avio_wb64(pb, av_double2int(val)); } static void put_ebml_binary(AVIOContext *pb, unsigned int elementid, const void *buf, int size) { put_ebml_id(pb, elementid); put_ebml_num(pb, size, 0); avio_write(pb, buf, size); } static void put_ebml_string(AVIOContext *pb, unsigned int elementid, const char *str) { put_ebml_binary(pb, elementid, str, strlen(str)); } /** * Write a void element of a given size. Useful for reserving space in * the file to be written to later. * * @param size The number of bytes to reserve, which must be at least 2. */ static void put_ebml_void(AVIOContext *pb, uint64_t size) { int64_t currentpos = avio_tell(pb); assert(size >= 2); put_ebml_id(pb, EBML_ID_VOID); // we need to subtract the length needed to store the size from the // size we need to reserve so 2 cases, we use 8 bytes to store the // size if possible, 1 byte otherwise if (size < 10) put_ebml_num(pb, size-1, 0); else put_ebml_num(pb, size-9, 8); while(avio_tell(pb) < currentpos + size) avio_w8(pb, 0); } static ebml_master start_ebml_master(AVIOContext *pb, unsigned int elementid, uint64_t expectedsize) { int bytes = expectedsize ? ebml_num_size(expectedsize) : 8; put_ebml_id(pb, elementid); put_ebml_size_unknown(pb, bytes); return (ebml_master){ avio_tell(pb), bytes }; } static void end_ebml_master(AVIOContext *pb, ebml_master master) { int64_t pos = avio_tell(pb); if (avio_seek(pb, master.pos - master.sizebytes, SEEK_SET) < 0) return; put_ebml_num(pb, pos - master.pos, master.sizebytes); avio_seek(pb, pos, SEEK_SET); } static void put_xiph_size(AVIOContext *pb, int size) { int i; for (i = 0; i < size / 255; i++) avio_w8(pb, 255); avio_w8(pb, size % 255); } /** * Initialize a mkv_seekhead element to be ready to index level 1 Matroska * elements. If a maximum number of elements is specified, enough space * will be reserved at the current file location to write a seek head of * that size. * * @param segment_offset The absolute offset to the position in the file * where the segment begins. * @param numelements The maximum number of elements that will be indexed * by this seek head, 0 if unlimited. */ static mkv_seekhead * mkv_start_seekhead(AVIOContext *pb, int64_t segment_offset, int numelements) { mkv_seekhead *new_seekhead = av_mallocz(sizeof(mkv_seekhead)); if (new_seekhead == NULL) return NULL; new_seekhead->segment_offset = segment_offset; if (numelements > 0) { new_seekhead->filepos = avio_tell(pb); // 21 bytes max for a seek entry, 10 bytes max for the SeekHead ID // and size, and 3 bytes to guarantee that an EBML void element // will fit afterwards new_seekhead->reserved_size = numelements * MAX_SEEKENTRY_SIZE + 13; new_seekhead->max_entries = numelements; put_ebml_void(pb, new_seekhead->reserved_size); } return new_seekhead; } static int mkv_add_seekhead_entry(mkv_seekhead *seekhead, unsigned int elementid, uint64_t filepos) { mkv_seekhead_entry *entries = seekhead->entries; // don't store more elements than we reserved space for if (seekhead->max_entries > 0 && seekhead->max_entries <= seekhead->num_entries) return -1; entries = av_realloc(entries, (seekhead->num_entries + 1) * sizeof(mkv_seekhead_entry)); if (entries == NULL) return AVERROR(ENOMEM); entries[seekhead->num_entries ].elementid = elementid; entries[seekhead->num_entries++].segmentpos = filepos - seekhead->segment_offset; seekhead->entries = entries; return 0; } /** * Write the seek head to the file and free it. If a maximum number of * elements was specified to mkv_start_seekhead(), the seek head will * be written at the location reserved for it. Otherwise, it is written * at the current location in the file. * * @return The file offset where the seekhead was written, * -1 if an error occurred. */ static int64_t mkv_write_seekhead(AVIOContext *pb, mkv_seekhead *seekhead) { ebml_master metaseek, seekentry; int64_t currentpos; int i; currentpos = avio_tell(pb); if (seekhead->reserved_size > 0) { if (avio_seek(pb, seekhead->filepos, SEEK_SET) < 0) { currentpos = -1; goto fail; } } metaseek = start_ebml_master(pb, MATROSKA_ID_SEEKHEAD, seekhead->reserved_size); for (i = 0; i < seekhead->num_entries; i++) { mkv_seekhead_entry *entry = &seekhead->entries[i]; seekentry = start_ebml_master(pb, MATROSKA_ID_SEEKENTRY, MAX_SEEKENTRY_SIZE); put_ebml_id(pb, MATROSKA_ID_SEEKID); put_ebml_num(pb, ebml_id_size(entry->elementid), 0); put_ebml_id(pb, entry->elementid); put_ebml_uint(pb, MATROSKA_ID_SEEKPOSITION, entry->segmentpos); end_ebml_master(pb, seekentry); } end_ebml_master(pb, metaseek); if (seekhead->reserved_size > 0) { uint64_t remaining = seekhead->filepos + seekhead->reserved_size - avio_tell(pb); put_ebml_void(pb, remaining); avio_seek(pb, currentpos, SEEK_SET); currentpos = seekhead->filepos; } fail: av_free(seekhead->entries); av_free(seekhead); return currentpos; } static mkv_cues * mkv_start_cues(int64_t segment_offset) { mkv_cues *cues = av_mallocz(sizeof(mkv_cues)); if (cues == NULL) return NULL; cues->segment_offset = segment_offset; return cues; } static int mkv_add_cuepoint(mkv_cues *cues, int stream, int64_t ts, int64_t cluster_pos) { mkv_cuepoint *entries = cues->entries; entries = av_realloc(entries, (cues->num_entries + 1) * sizeof(mkv_cuepoint)); if (entries == NULL) return AVERROR(ENOMEM); if (ts < 0) return 0; entries[cues->num_entries ].pts = ts; entries[cues->num_entries ].tracknum = stream + 1; entries[cues->num_entries++].cluster_pos = cluster_pos - cues->segment_offset; cues->entries = entries; return 0; } static int64_t mkv_write_cues(AVIOContext *pb, mkv_cues *cues, int num_tracks) { ebml_master cues_element; int64_t currentpos; int i, j; currentpos = avio_tell(pb); cues_element = start_ebml_master(pb, MATROSKA_ID_CUES, 0); for (i = 0; i < cues->num_entries; i++) { ebml_master cuepoint, track_positions; mkv_cuepoint *entry = &cues->entries[i]; uint64_t pts = entry->pts; cuepoint = start_ebml_master(pb, MATROSKA_ID_POINTENTRY, MAX_CUEPOINT_SIZE(num_tracks)); put_ebml_uint(pb, MATROSKA_ID_CUETIME, pts); // put all the entries from different tracks that have the exact same // timestamp into the same CuePoint for (j = 0; j < cues->num_entries - i && entry[j].pts == pts; j++) { track_positions = start_ebml_master(pb, MATROSKA_ID_CUETRACKPOSITION, MAX_CUETRACKPOS_SIZE); put_ebml_uint(pb, MATROSKA_ID_CUETRACK , entry[j].tracknum ); put_ebml_uint(pb, MATROSKA_ID_CUECLUSTERPOSITION, entry[j].cluster_pos); end_ebml_master(pb, track_positions); } i += j - 1; end_ebml_master(pb, cuepoint); } end_ebml_master(pb, cues_element); return currentpos; } static int put_xiph_codecpriv(AVFormatContext *s, AVIOContext *pb, AVCodecContext *codec) { uint8_t *header_start[3]; int header_len[3]; int first_header_size; int j; if (codec->codec_id == CODEC_ID_VORBIS) first_header_size = 30; else first_header_size = 42; if (avpriv_split_xiph_headers(codec->extradata, codec->extradata_size, first_header_size, header_start, header_len) < 0) { av_log(s, AV_LOG_ERROR, "Extradata corrupt.\n"); return -1; } avio_w8(pb, 2); // number packets - 1 for (j = 0; j < 2; j++) { put_xiph_size(pb, header_len[j]); } for (j = 0; j < 3; j++) avio_write(pb, header_start[j], header_len[j]); return 0; } static void get_aac_sample_rates(AVFormatContext *s, AVCodecContext *codec, int *sample_rate, int *output_sample_rate) { MPEG4AudioConfig mp4ac; if (avpriv_mpeg4audio_get_config(&mp4ac, codec->extradata, codec->extradata_size * 8, 1) < 0) { av_log(s, AV_LOG_WARNING, "Error parsing AAC extradata, unable to determine samplerate.\n"); return; } *sample_rate = mp4ac.sample_rate; *output_sample_rate = mp4ac.ext_sample_rate; } static int mkv_write_codecprivate(AVFormatContext *s, AVIOContext *pb, AVCodecContext *codec, int native_id, int qt_id) { AVIOContext *dyn_cp; uint8_t *codecpriv; int ret, codecpriv_size; ret = avio_open_dyn_buf(&dyn_cp); if(ret < 0) return ret; if (native_id) { if (codec->codec_id == CODEC_ID_VORBIS || codec->codec_id == CODEC_ID_THEORA) ret = put_xiph_codecpriv(s, dyn_cp, codec); else if (codec->codec_id == CODEC_ID_FLAC) ret = ff_flac_write_header(dyn_cp, codec, 1); else if (codec->codec_id == CODEC_ID_H264) ret = ff_isom_write_avcc(dyn_cp, codec->extradata, codec->extradata_size); else if (codec->extradata_size) avio_write(dyn_cp, codec->extradata, codec->extradata_size); } else if (codec->codec_type == AVMEDIA_TYPE_VIDEO) { if (qt_id) { if (!codec->codec_tag) codec->codec_tag = ff_codec_get_tag(codec_movvideo_tags, codec->codec_id); if (codec->extradata_size) avio_write(dyn_cp, codec->extradata, codec->extradata_size); } else { if (!codec->codec_tag) codec->codec_tag = ff_codec_get_tag(ff_codec_bmp_tags, codec->codec_id); if (!codec->codec_tag) { av_log(s, AV_LOG_ERROR, "No bmp codec ID found.\n"); ret = -1; } ff_put_bmp_header(dyn_cp, codec, ff_codec_bmp_tags, 0); } } else if (codec->codec_type == AVMEDIA_TYPE_AUDIO) { unsigned int tag; tag = ff_codec_get_tag(ff_codec_wav_tags, codec->codec_id); if (!tag) { av_log(s, AV_LOG_ERROR, "No wav codec ID found.\n"); ret = -1; } if (!codec->codec_tag) codec->codec_tag = tag; ff_put_wav_header(dyn_cp, codec); } codecpriv_size = avio_close_dyn_buf(dyn_cp, &codecpriv); if (codecpriv_size) put_ebml_binary(pb, MATROSKA_ID_CODECPRIVATE, codecpriv, codecpriv_size); av_free(codecpriv); return ret; } static int mkv_write_tracks(AVFormatContext *s) { MatroskaMuxContext *mkv = s->priv_data; AVIOContext *pb = s->pb; ebml_master tracks; int i, j, ret; ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_TRACKS, avio_tell(pb)); if (ret < 0) return ret; tracks = start_ebml_master(pb, MATROSKA_ID_TRACKS, 0); for (i = 0; i < s->nb_streams; i++) { AVStream *st = s->streams[i]; AVCodecContext *codec = st->codec; ebml_master subinfo, track; int native_id = 0; int qt_id = 0; int bit_depth = av_get_bits_per_sample(codec->codec_id); int sample_rate = codec->sample_rate; int output_sample_rate = 0; AVDictionaryEntry *tag; if (codec->codec_type == AVMEDIA_TYPE_ATTACHMENT) { mkv->have_attachments = 1; continue; } if (!bit_depth) bit_depth = av_get_bytes_per_sample(codec->sample_fmt) << 3; if (codec->codec_id == CODEC_ID_AAC) get_aac_sample_rates(s, codec, &sample_rate, &output_sample_rate); track = start_ebml_master(pb, MATROSKA_ID_TRACKENTRY, 0); put_ebml_uint (pb, MATROSKA_ID_TRACKNUMBER , i + 1); put_ebml_uint (pb, MATROSKA_ID_TRACKUID , i + 1); put_ebml_uint (pb, MATROSKA_ID_TRACKFLAGLACING , 0); // no lacing (yet) if ((tag = av_dict_get(st->metadata, "title", NULL, 0))) put_ebml_string(pb, MATROSKA_ID_TRACKNAME, tag->value); tag = av_dict_get(st->metadata, "language", NULL, 0); put_ebml_string(pb, MATROSKA_ID_TRACKLANGUAGE, tag ? tag->value:"und"); if (st->disposition) put_ebml_uint(pb, MATROSKA_ID_TRACKFLAGDEFAULT, !!(st->disposition & AV_DISPOSITION_DEFAULT)); // look for a codec ID string specific to mkv to use, // if none are found, use AVI codes for (j = 0; ff_mkv_codec_tags[j].id != CODEC_ID_NONE; j++) { if (ff_mkv_codec_tags[j].id == codec->codec_id) { put_ebml_string(pb, MATROSKA_ID_CODECID, ff_mkv_codec_tags[j].str); native_id = 1; break; } } if (mkv->mode == MODE_WEBM && !(codec->codec_id == CODEC_ID_VP8 || codec->codec_id == CODEC_ID_VORBIS)) { av_log(s, AV_LOG_ERROR, "Only VP8 video and Vorbis audio are supported for WebM.\n"); return AVERROR(EINVAL); } switch (codec->codec_type) { case AVMEDIA_TYPE_VIDEO: put_ebml_uint(pb, MATROSKA_ID_TRACKTYPE, MATROSKA_TRACK_TYPE_VIDEO); if(st->avg_frame_rate.num && st->avg_frame_rate.den && 1.0/av_q2d(st->avg_frame_rate) > av_q2d(codec->time_base)) put_ebml_uint(pb, MATROSKA_ID_TRACKDEFAULTDURATION, 1E9/av_q2d(st->avg_frame_rate)); else put_ebml_uint(pb, MATROSKA_ID_TRACKDEFAULTDURATION, av_q2d(codec->time_base)*1E9); if (!native_id && ff_codec_get_tag(codec_movvideo_tags, codec->codec_id) && (!ff_codec_get_tag(ff_codec_bmp_tags, codec->codec_id) || codec->codec_id == CODEC_ID_SVQ1 || codec->codec_id == CODEC_ID_SVQ3 || codec->codec_id == CODEC_ID_CINEPAK)) qt_id = 1; if (qt_id) put_ebml_string(pb, MATROSKA_ID_CODECID, "V_QUICKTIME"); else if (!native_id) { // if there is no mkv-specific codec ID, use VFW mode put_ebml_string(pb, MATROSKA_ID_CODECID, "V_MS/VFW/FOURCC"); mkv->tracks[i].write_dts = 1; } subinfo = start_ebml_master(pb, MATROSKA_ID_TRACKVIDEO, 0); // XXX: interlace flag? put_ebml_uint (pb, MATROSKA_ID_VIDEOPIXELWIDTH , codec->width); put_ebml_uint (pb, MATROSKA_ID_VIDEOPIXELHEIGHT, codec->height); if ((tag = av_dict_get(st->metadata, "stereo_mode", NULL, 0)) || (tag = av_dict_get( s->metadata, "stereo_mode", NULL, 0))) { // save stereo mode flag uint64_t st_mode = MATROSKA_VIDEO_STEREO_MODE_COUNT; for (j=0; j<MATROSKA_VIDEO_STEREO_MODE_COUNT; j++) if (!strcmp(tag->value, matroska_video_stereo_mode[j])){ st_mode = j; break; } if ((mkv->mode == MODE_WEBM && st_mode > 3 && st_mode != 11) || st_mode >= MATROSKA_VIDEO_STEREO_MODE_COUNT) { av_log(s, AV_LOG_ERROR, "The specified stereo mode is not valid.\n"); return AVERROR(EINVAL); } else put_ebml_uint(pb, MATROSKA_ID_VIDEOSTEREOMODE, st_mode); } if (st->sample_aspect_ratio.num) { int d_width = codec->width*av_q2d(st->sample_aspect_ratio); put_ebml_uint(pb, MATROSKA_ID_VIDEODISPLAYWIDTH , d_width); put_ebml_uint(pb, MATROSKA_ID_VIDEODISPLAYHEIGHT, codec->height); put_ebml_uint(pb, MATROSKA_ID_VIDEODISPLAYUNIT, 3); } if (codec->codec_id == CODEC_ID_RAWVIDEO) { uint32_t color_space = av_le2ne32(codec->codec_tag); put_ebml_binary(pb, MATROSKA_ID_VIDEOCOLORSPACE, &color_space, sizeof(color_space)); } end_ebml_master(pb, subinfo); break; case AVMEDIA_TYPE_AUDIO: put_ebml_uint(pb, MATROSKA_ID_TRACKTYPE, MATROSKA_TRACK_TYPE_AUDIO); if (!native_id) // no mkv-specific ID, use ACM mode put_ebml_string(pb, MATROSKA_ID_CODECID, "A_MS/ACM"); subinfo = start_ebml_master(pb, MATROSKA_ID_TRACKAUDIO, 0); put_ebml_uint (pb, MATROSKA_ID_AUDIOCHANNELS , codec->channels); put_ebml_float (pb, MATROSKA_ID_AUDIOSAMPLINGFREQ, sample_rate); if (output_sample_rate) put_ebml_float(pb, MATROSKA_ID_AUDIOOUTSAMPLINGFREQ, output_sample_rate); if (bit_depth) put_ebml_uint(pb, MATROSKA_ID_AUDIOBITDEPTH, bit_depth); end_ebml_master(pb, subinfo); break; case AVMEDIA_TYPE_SUBTITLE: put_ebml_uint(pb, MATROSKA_ID_TRACKTYPE, MATROSKA_TRACK_TYPE_SUBTITLE); if (!native_id) { av_log(s, AV_LOG_ERROR, "Subtitle codec %d is not supported.\n", codec->codec_id); return AVERROR(ENOSYS); } break; default: av_log(s, AV_LOG_ERROR, "Only audio, video, and subtitles are supported for Matroska.\n"); break; } ret = mkv_write_codecprivate(s, pb, codec, native_id, qt_id); if (ret < 0) return ret; end_ebml_master(pb, track); // ms precision is the de-facto standard timescale for mkv files avpriv_set_pts_info(st, 64, 1, 1000); } end_ebml_master(pb, tracks); return 0; } static int mkv_write_chapters(AVFormatContext *s) { MatroskaMuxContext *mkv = s->priv_data; AVIOContext *pb = s->pb; ebml_master chapters, editionentry; AVRational scale = {1, 1E9}; int i, ret; if (!s->nb_chapters) return 0; ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_CHAPTERS, avio_tell(pb)); if (ret < 0) return ret; chapters = start_ebml_master(pb, MATROSKA_ID_CHAPTERS , 0); editionentry = start_ebml_master(pb, MATROSKA_ID_EDITIONENTRY, 0); put_ebml_uint(pb, MATROSKA_ID_EDITIONFLAGDEFAULT, 1); put_ebml_uint(pb, MATROSKA_ID_EDITIONFLAGHIDDEN , 0); for (i = 0; i < s->nb_chapters; i++) { ebml_master chapteratom, chapterdisplay; AVChapter *c = s->chapters[i]; AVDictionaryEntry *t = NULL; chapteratom = start_ebml_master(pb, MATROSKA_ID_CHAPTERATOM, 0); put_ebml_uint(pb, MATROSKA_ID_CHAPTERUID, c->id); put_ebml_uint(pb, MATROSKA_ID_CHAPTERTIMESTART, av_rescale_q(c->start, c->time_base, scale)); put_ebml_uint(pb, MATROSKA_ID_CHAPTERTIMEEND, av_rescale_q(c->end, c->time_base, scale)); put_ebml_uint(pb, MATROSKA_ID_CHAPTERFLAGHIDDEN , 0); put_ebml_uint(pb, MATROSKA_ID_CHAPTERFLAGENABLED, 1); if ((t = av_dict_get(c->metadata, "title", NULL, 0))) { chapterdisplay = start_ebml_master(pb, MATROSKA_ID_CHAPTERDISPLAY, 0); put_ebml_string(pb, MATROSKA_ID_CHAPSTRING, t->value); put_ebml_string(pb, MATROSKA_ID_CHAPLANG , "und"); end_ebml_master(pb, chapterdisplay); } end_ebml_master(pb, chapteratom); } end_ebml_master(pb, editionentry); end_ebml_master(pb, chapters); return 0; } static void mkv_write_simpletag(AVIOContext *pb, AVDictionaryEntry *t) { uint8_t *key = av_strdup(t->key); uint8_t *p = key; const uint8_t *lang = NULL; ebml_master tag; if ((p = strrchr(p, '-')) && (lang = av_convert_lang_to(p + 1, AV_LANG_ISO639_2_BIBL))) *p = 0; p = key; while (*p) { if (*p == ' ') *p = '_'; else if (*p >= 'a' && *p <= 'z') *p -= 'a' - 'A'; p++; } tag = start_ebml_master(pb, MATROSKA_ID_SIMPLETAG, 0); put_ebml_string(pb, MATROSKA_ID_TAGNAME, key); if (lang) put_ebml_string(pb, MATROSKA_ID_TAGLANG, lang); put_ebml_string(pb, MATROSKA_ID_TAGSTRING, t->value); end_ebml_master(pb, tag); av_freep(&key); } static int mkv_write_tag(AVFormatContext *s, AVDictionary *m, unsigned int elementid, unsigned int uid, ebml_master *tags) { MatroskaMuxContext *mkv = s->priv_data; ebml_master tag, targets; AVDictionaryEntry *t = NULL; int ret; if (!tags->pos) { ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_TAGS, avio_tell(s->pb)); if (ret < 0) return ret; *tags = start_ebml_master(s->pb, MATROSKA_ID_TAGS, 0); } tag = start_ebml_master(s->pb, MATROSKA_ID_TAG, 0); targets = start_ebml_master(s->pb, MATROSKA_ID_TAGTARGETS, 0); if (elementid) put_ebml_uint(s->pb, elementid, uid); end_ebml_master(s->pb, targets); while ((t = av_dict_get(m, "", t, AV_DICT_IGNORE_SUFFIX))) if (av_strcasecmp(t->key, "title") && av_strcasecmp(t->key, "stereo_mode")) mkv_write_simpletag(s->pb, t); end_ebml_master(s->pb, tag); return 0; } static int mkv_write_tags(AVFormatContext *s) { ebml_master tags = {0}; int i, ret; ff_metadata_conv_ctx(s, ff_mkv_metadata_conv, NULL); if (av_dict_get(s->metadata, "", NULL, AV_DICT_IGNORE_SUFFIX)) { ret = mkv_write_tag(s, s->metadata, 0, 0, &tags); if (ret < 0) return ret; } for (i = 0; i < s->nb_streams; i++) { AVStream *st = s->streams[i]; if (!av_dict_get(st->metadata, "", 0, AV_DICT_IGNORE_SUFFIX)) continue; ret = mkv_write_tag(s, st->metadata, MATROSKA_ID_TAGTARGETS_TRACKUID, i + 1, &tags); if (ret < 0) return ret; } for (i = 0; i < s->nb_chapters; i++) { AVChapter *ch = s->chapters[i]; if (!av_dict_get(ch->metadata, "", NULL, AV_DICT_IGNORE_SUFFIX)) continue; ret = mkv_write_tag(s, ch->metadata, MATROSKA_ID_TAGTARGETS_CHAPTERUID, ch->id, &tags); if (ret < 0) return ret; } if (tags.pos) end_ebml_master(s->pb, tags); return 0; } static int mkv_write_attachments(AVFormatContext *s) { MatroskaMuxContext *mkv = s->priv_data; AVIOContext *pb = s->pb; ebml_master attachments; AVLFG c; int i, ret; if (!mkv->have_attachments) return 0; av_lfg_init(&c, av_get_random_seed()); ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_ATTACHMENTS, avio_tell(pb)); if (ret < 0) return ret; attachments = start_ebml_master(pb, MATROSKA_ID_ATTACHMENTS, 0); for (i = 0; i < s->nb_streams; i++) { AVStream *st = s->streams[i]; ebml_master attached_file; AVDictionaryEntry *t; const char *mimetype = NULL; if (st->codec->codec_type != AVMEDIA_TYPE_ATTACHMENT) continue; attached_file = start_ebml_master(pb, MATROSKA_ID_ATTACHEDFILE, 0); if (t = av_dict_get(st->metadata, "title", NULL, 0)) put_ebml_string(pb, MATROSKA_ID_FILEDESC, t->value); if (!(t = av_dict_get(st->metadata, "filename", NULL, 0))) { av_log(s, AV_LOG_ERROR, "Attachment stream %d has no filename tag.\n", i); return AVERROR(EINVAL); } put_ebml_string(pb, MATROSKA_ID_FILENAME, t->value); if (t = av_dict_get(st->metadata, "mimetype", NULL, 0)) mimetype = t->value; else if (st->codec->codec_id != CODEC_ID_NONE ) { int i; for (i = 0; ff_mkv_mime_tags[i].id != CODEC_ID_NONE; i++) if (ff_mkv_mime_tags[i].id == st->codec->codec_id) { mimetype = ff_mkv_mime_tags[i].str; break; } } if (!mimetype) { av_log(s, AV_LOG_ERROR, "Attachment stream %d has no mimetype tag and " "it cannot be deduced from the codec id.\n", i); return AVERROR(EINVAL); } put_ebml_string(pb, MATROSKA_ID_FILEMIMETYPE, mimetype); put_ebml_binary(pb, MATROSKA_ID_FILEDATA, st->codec->extradata, st->codec->extradata_size); put_ebml_uint(pb, MATROSKA_ID_FILEUID, av_lfg_get(&c)); end_ebml_master(pb, attached_file); } end_ebml_master(pb, attachments); return 0; } static int mkv_write_header(AVFormatContext *s) { MatroskaMuxContext *mkv = s->priv_data; AVIOContext *pb = s->pb; ebml_master ebml_header, segment_info; AVDictionaryEntry *tag; int ret, i; if (!strcmp(s->oformat->name, "webm")) mkv->mode = MODE_WEBM; else mkv->mode = MODE_MATROSKAv2; mkv->tracks = av_mallocz(s->nb_streams * sizeof(*mkv->tracks)); if (!mkv->tracks) return AVERROR(ENOMEM); ebml_header = start_ebml_master(pb, EBML_ID_HEADER, 0); put_ebml_uint (pb, EBML_ID_EBMLVERSION , 1); put_ebml_uint (pb, EBML_ID_EBMLREADVERSION , 1); put_ebml_uint (pb, EBML_ID_EBMLMAXIDLENGTH , 4); put_ebml_uint (pb, EBML_ID_EBMLMAXSIZELENGTH , 8); put_ebml_string (pb, EBML_ID_DOCTYPE , s->oformat->name); put_ebml_uint (pb, EBML_ID_DOCTYPEVERSION , 2); put_ebml_uint (pb, EBML_ID_DOCTYPEREADVERSION , 2); end_ebml_master(pb, ebml_header); mkv->segment = start_ebml_master(pb, MATROSKA_ID_SEGMENT, 0); mkv->segment_offset = avio_tell(pb); // we write 2 seek heads - one at the end of the file to point to each // cluster, and one at the beginning to point to all other level one // elements (including the seek head at the end of the file), which // isn't more than 10 elements if we only write one of each other // currently defined level 1 element mkv->main_seekhead = mkv_start_seekhead(pb, mkv->segment_offset, 10); if (!mkv->main_seekhead) return AVERROR(ENOMEM); ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_INFO, avio_tell(pb)); if (ret < 0) return ret; segment_info = start_ebml_master(pb, MATROSKA_ID_INFO, 0); put_ebml_uint(pb, MATROSKA_ID_TIMECODESCALE, 1000000); if ((tag = av_dict_get(s->metadata, "title", NULL, 0))) put_ebml_string(pb, MATROSKA_ID_TITLE, tag->value); if (!(s->streams[0]->codec->flags & CODEC_FLAG_BITEXACT)) { uint32_t segment_uid[4]; AVLFG lfg; av_lfg_init(&lfg, av_get_random_seed()); for (i = 0; i < 4; i++) segment_uid[i] = av_lfg_get(&lfg); put_ebml_string(pb, MATROSKA_ID_MUXINGAPP , LIBAVFORMAT_IDENT); put_ebml_string(pb, MATROSKA_ID_WRITINGAPP, LIBAVFORMAT_IDENT); put_ebml_binary(pb, MATROSKA_ID_SEGMENTUID, segment_uid, 16); } // reserve space for the duration mkv->duration = 0; mkv->duration_offset = avio_tell(pb); put_ebml_void(pb, 11); // assumes double-precision float to be written end_ebml_master(pb, segment_info); ret = mkv_write_tracks(s); if (ret < 0) return ret; if (mkv->mode != MODE_WEBM) { ret = mkv_write_chapters(s); if (ret < 0) return ret; ret = mkv_write_tags(s); if (ret < 0) return ret; ret = mkv_write_attachments(s); if (ret < 0) return ret; } if (!s->pb->seekable) mkv_write_seekhead(pb, mkv->main_seekhead); mkv->cues = mkv_start_cues(mkv->segment_offset); if (mkv->cues == NULL) return AVERROR(ENOMEM); av_init_packet(&mkv->cur_audio_pkt); mkv->cur_audio_pkt.size = 0; mkv->audio_buffer_size = 0; avio_flush(pb); return 0; } static int mkv_blockgroup_size(int pkt_size) { int size = pkt_size + 4; size += ebml_num_size(size); size += 2; // EBML ID for block and block duration size += 8; // max size of block duration size += ebml_num_size(size); size += 1; // blockgroup EBML ID return size; } static int ass_get_duration(const uint8_t *p) { int sh, sm, ss, sc, eh, em, es, ec; uint64_t start, end; if (sscanf(p, "%*[^,],%d:%d:%d%*c%d,%d:%d:%d%*c%d", &sh, &sm, &ss, &sc, &eh, &em, &es, &ec) != 8) return 0; start = 3600000*sh + 60000*sm + 1000*ss + 10*sc; end = 3600000*eh + 60000*em + 1000*es + 10*ec; return end - start; } static int mkv_write_ass_blocks(AVFormatContext *s, AVIOContext *pb, AVPacket *pkt) { MatroskaMuxContext *mkv = s->priv_data; int i, layer = 0, max_duration = 0, size, line_size, data_size = pkt->size; uint8_t *start, *end, *data = pkt->data; ebml_master blockgroup; char buffer[2048]; while (data_size) { int duration = ass_get_duration(data); max_duration = FFMAX(duration, max_duration); end = memchr(data, '\n', data_size); size = line_size = end ? end-data+1 : data_size; size -= end ? (end[-1]=='\r')+1 : 0; start = data; for (i=0; i<3; i++, start++) if (!(start = memchr(start, ',', size-(start-data)))) return max_duration; size -= start - data; sscanf(data, "Dialogue: %d,", &layer); i = snprintf(buffer, sizeof(buffer), "%"PRId64",%d,", s->streams[pkt->stream_index]->nb_frames, layer); size = FFMIN(i+size, sizeof(buffer)); memcpy(buffer+i, start, size-i); av_log(s, AV_LOG_DEBUG, "Writing block at offset %" PRIu64 ", size %d, " "pts %" PRId64 ", duration %d\n", avio_tell(pb), size, pkt->pts, duration); blockgroup = start_ebml_master(pb, MATROSKA_ID_BLOCKGROUP, mkv_blockgroup_size(size)); put_ebml_id(pb, MATROSKA_ID_BLOCK); put_ebml_num(pb, size+4, 0); avio_w8(pb, 0x80 | (pkt->stream_index + 1)); // this assumes stream_index is less than 126 avio_wb16(pb, pkt->pts - mkv->cluster_pts); avio_w8(pb, 0); avio_write(pb, buffer, size); put_ebml_uint(pb, MATROSKA_ID_BLOCKDURATION, duration); end_ebml_master(pb, blockgroup); data += line_size; data_size -= line_size; } return max_duration; } static void mkv_write_block(AVFormatContext *s, AVIOContext *pb, unsigned int blockid, AVPacket *pkt, int flags) { MatroskaMuxContext *mkv = s->priv_data; AVCodecContext *codec = s->streams[pkt->stream_index]->codec; uint8_t *data = NULL; int size = pkt->size; int64_t ts = mkv->tracks[pkt->stream_index].write_dts ? pkt->dts : pkt->pts; av_log(s, AV_LOG_DEBUG, "Writing block at offset %" PRIu64 ", size %d, " "pts %" PRId64 ", dts %" PRId64 ", duration %d, flags %d\n", avio_tell(pb), pkt->size, pkt->pts, pkt->dts, pkt->duration, flags); if (codec->codec_id == CODEC_ID_H264 && codec->extradata_size > 0 && (AV_RB24(codec->extradata) == 1 || AV_RB32(codec->extradata) == 1)) ff_avc_parse_nal_units_buf(pkt->data, &data, &size); else data = pkt->data; put_ebml_id(pb, blockid); put_ebml_num(pb, size+4, 0); avio_w8(pb, 0x80 | (pkt->stream_index + 1)); // this assumes stream_index is less than 126 avio_wb16(pb, ts - mkv->cluster_pts); avio_w8(pb, flags); avio_write(pb, data, size); if (data != pkt->data) av_free(data); } static int srt_get_duration(uint8_t **buf) { int i, duration = 0; for (i=0; i<2 && !duration; i++) { int s_hour, s_min, s_sec, s_hsec, e_hour, e_min, e_sec, e_hsec; if (sscanf(*buf, "%d:%2d:%2d%*1[,.]%3d --> %d:%2d:%2d%*1[,.]%3d", &s_hour, &s_min, &s_sec, &s_hsec, &e_hour, &e_min, &e_sec, &e_hsec) == 8) { s_min += 60*s_hour; e_min += 60*e_hour; s_sec += 60*s_min; e_sec += 60*e_min; s_hsec += 1000*s_sec; e_hsec += 1000*e_sec; duration = e_hsec - s_hsec; } *buf += strcspn(*buf, "\n") + 1; } return duration; } static int mkv_write_srt_blocks(AVFormatContext *s, AVIOContext *pb, AVPacket *pkt) { ebml_master blockgroup; AVPacket pkt2 = *pkt; int64_t duration = srt_get_duration(&pkt2.data); pkt2.size -= pkt2.data - pkt->data; blockgroup = start_ebml_master(pb, MATROSKA_ID_BLOCKGROUP, mkv_blockgroup_size(pkt2.size)); mkv_write_block(s, pb, MATROSKA_ID_BLOCK, &pkt2, 0); put_ebml_uint(pb, MATROSKA_ID_BLOCKDURATION, duration); end_ebml_master(pb, blockgroup); return duration; } static void mkv_flush_dynbuf(AVFormatContext *s) { MatroskaMuxContext *mkv = s->priv_data; int bufsize; uint8_t *dyn_buf; if (!mkv->dyn_bc) return; bufsize = avio_close_dyn_buf(mkv->dyn_bc, &dyn_buf); avio_write(s->pb, dyn_buf, bufsize); av_free(dyn_buf); mkv->dyn_bc = NULL; } static int mkv_write_packet_internal(AVFormatContext *s, AVPacket *pkt) { MatroskaMuxContext *mkv = s->priv_data; AVIOContext *pb = s->pb; AVCodecContext *codec = s->streams[pkt->stream_index]->codec; int keyframe = !!(pkt->flags & AV_PKT_FLAG_KEY); int duration = pkt->duration; int ret; int64_t ts = mkv->tracks[pkt->stream_index].write_dts ? pkt->dts : pkt->pts; if (ts == AV_NOPTS_VALUE) { av_log(s, AV_LOG_ERROR, "Can't write packet with unknown timestamp\n"); return AVERROR(EINVAL); } if (!s->pb->seekable) { if (!mkv->dyn_bc) avio_open_dyn_buf(&mkv->dyn_bc); pb = mkv->dyn_bc; } if (!mkv->cluster_pos) { mkv->cluster_pos = avio_tell(s->pb); mkv->cluster = start_ebml_master(pb, MATROSKA_ID_CLUSTER, 0); put_ebml_uint(pb, MATROSKA_ID_CLUSTERTIMECODE, FFMAX(0, ts)); mkv->cluster_pts = FFMAX(0, ts); } if (codec->codec_type != AVMEDIA_TYPE_SUBTITLE) { mkv_write_block(s, pb, MATROSKA_ID_SIMPLEBLOCK, pkt, keyframe << 7); } else if (codec->codec_id == CODEC_ID_SSA) { duration = mkv_write_ass_blocks(s, pb, pkt); } else if (codec->codec_id == CODEC_ID_SRT) { duration = mkv_write_srt_blocks(s, pb, pkt); } else { ebml_master blockgroup = start_ebml_master(pb, MATROSKA_ID_BLOCKGROUP, mkv_blockgroup_size(pkt->size)); duration = pkt->convergence_duration; mkv_write_block(s, pb, MATROSKA_ID_BLOCK, pkt, 0); put_ebml_uint(pb, MATROSKA_ID_BLOCKDURATION, duration); end_ebml_master(pb, blockgroup); } if (codec->codec_type == AVMEDIA_TYPE_VIDEO && keyframe) { ret = mkv_add_cuepoint(mkv->cues, pkt->stream_index, ts, mkv->cluster_pos); if (ret < 0) return ret; } mkv->duration = FFMAX(mkv->duration, ts + duration); return 0; } static int mkv_copy_packet(MatroskaMuxContext *mkv, const AVPacket *pkt) { uint8_t *data = mkv->cur_audio_pkt.data; mkv->cur_audio_pkt = *pkt; mkv->cur_audio_pkt.data = av_fast_realloc(data, &mkv->audio_buffer_size, pkt->size); if (!mkv->cur_audio_pkt.data) return AVERROR(ENOMEM); memcpy(mkv->cur_audio_pkt.data, pkt->data, pkt->size); mkv->cur_audio_pkt.size = pkt->size; return 0; } static int mkv_write_packet(AVFormatContext *s, AVPacket *pkt) { MatroskaMuxContext *mkv = s->priv_data; AVIOContext *pb = s->pb->seekable ? s->pb : mkv->dyn_bc; AVCodecContext *codec = s->streams[pkt->stream_index]->codec; int ret, keyframe = !!(pkt->flags & AV_PKT_FLAG_KEY); int64_t ts = mkv->tracks[pkt->stream_index].write_dts ? pkt->dts : pkt->pts; int cluster_size = avio_tell(pb) - (s->pb->seekable ? mkv->cluster_pos : 0); // start a new cluster every 5 MB or 5 sec, or 32k / 1 sec for streaming or // after 4k and on a keyframe if (mkv->cluster_pos && ((!s->pb->seekable && (cluster_size > 32*1024 || ts > mkv->cluster_pts + 1000)) || cluster_size > 5*1024*1024 || ts > mkv->cluster_pts + 5000 || (codec->codec_type == AVMEDIA_TYPE_VIDEO && keyframe && cluster_size > 4*1024))) { av_log(s, AV_LOG_DEBUG, "Starting new cluster at offset %" PRIu64 " bytes, pts %" PRIu64 "\n", avio_tell(pb), ts); end_ebml_master(pb, mkv->cluster); mkv->cluster_pos = 0; if (mkv->dyn_bc) mkv_flush_dynbuf(s); } // check if we have an audio packet cached if (mkv->cur_audio_pkt.size > 0) { ret = mkv_write_packet_internal(s, &mkv->cur_audio_pkt); mkv->cur_audio_pkt.size = 0; if (ret < 0) { av_log(s, AV_LOG_ERROR, "Could not write cached audio packet ret:%d\n", ret); return ret; } } // buffer an audio packet to ensure the packet containing the video // keyframe's timecode is contained in the same cluster for WebM if (codec->codec_type == AVMEDIA_TYPE_AUDIO) ret = mkv_copy_packet(mkv, pkt); else ret = mkv_write_packet_internal(s, pkt); return ret; } static int mkv_write_trailer(AVFormatContext *s) { MatroskaMuxContext *mkv = s->priv_data; AVIOContext *pb = s->pb; int64_t currentpos, cuespos; int ret; // check if we have an audio packet cached if (mkv->cur_audio_pkt.size > 0) { ret = mkv_write_packet_internal(s, &mkv->cur_audio_pkt); mkv->cur_audio_pkt.size = 0; if (ret < 0) { av_log(s, AV_LOG_ERROR, "Could not write cached audio packet ret:%d\n", ret); return ret; } } if (mkv->dyn_bc) { end_ebml_master(mkv->dyn_bc, mkv->cluster); mkv_flush_dynbuf(s); } else if (mkv->cluster_pos) { end_ebml_master(pb, mkv->cluster); } if (pb->seekable) { if (mkv->cues->num_entries) { cuespos = mkv_write_cues(pb, mkv->cues, s->nb_streams); ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_CUES, cuespos); if (ret < 0) return ret; } mkv_write_seekhead(pb, mkv->main_seekhead); // update the duration av_log(s, AV_LOG_DEBUG, "end duration = %" PRIu64 "\n", mkv->duration); currentpos = avio_tell(pb); avio_seek(pb, mkv->duration_offset, SEEK_SET); put_ebml_float(pb, MATROSKA_ID_DURATION, mkv->duration); avio_seek(pb, currentpos, SEEK_SET); } end_ebml_master(pb, mkv->segment); av_free(mkv->tracks); av_freep(&mkv->cues->entries); av_freep(&mkv->cues); av_destruct_packet(&mkv->cur_audio_pkt); avio_flush(pb); return 0; } static int mkv_query_codec(enum CodecID codec_id, int std_compliance) { int i; for (i = 0; ff_mkv_codec_tags[i].id != CODEC_ID_NONE; i++) if (ff_mkv_codec_tags[i].id == codec_id) return 1; if (std_compliance < FF_COMPLIANCE_NORMAL) { // mkv theoretically supports any enum AVMediaType type = avcodec_get_type(codec_id); // video/audio through VFW/ACM if (type == AVMEDIA_TYPE_VIDEO || type == AVMEDIA_TYPE_AUDIO) return 1; } return 0; } #if CONFIG_MATROSKA_MUXER AVOutputFormat ff_matroska_muxer = { .name = "matroska", .long_name = NULL_IF_CONFIG_SMALL("Matroska file format"), .mime_type = "video/x-matroska", .extensions = "mkv", .priv_data_size = sizeof(MatroskaMuxContext), #if CONFIG_LIBVORBIS_ENCODER .audio_codec = CODEC_ID_VORBIS, #else .audio_codec = CODEC_ID_AC3, #endif #if CONFIG_LIBX264_ENCODER .video_codec = CODEC_ID_H264, #else .video_codec = CODEC_ID_MPEG4, #endif .write_header = mkv_write_header, .write_packet = mkv_write_packet, .write_trailer = mkv_write_trailer, .flags = AVFMT_GLOBALHEADER | AVFMT_VARIABLE_FPS, .subtitle_codec = CODEC_ID_SSA, .query_codec = mkv_query_codec, }; #endif #if CONFIG_WEBM_MUXER AVOutputFormat ff_webm_muxer = { .name = "webm", .long_name = NULL_IF_CONFIG_SMALL("WebM file format"), .mime_type = "video/webm", .extensions = "webm", .priv_data_size = sizeof(MatroskaMuxContext), .audio_codec = CODEC_ID_VORBIS, .video_codec = CODEC_ID_VP8, .write_header = mkv_write_header, .write_packet = mkv_write_packet, .write_trailer = mkv_write_trailer, .flags = AVFMT_GLOBALHEADER | AVFMT_VARIABLE_FPS | AVFMT_TS_NONSTRICT, }; #endif #if CONFIG_MATROSKA_AUDIO_MUXER AVOutputFormat ff_matroska_audio_muxer = { .name = "matroska", .long_name = NULL_IF_CONFIG_SMALL("Matroska file format"), .mime_type = "audio/x-matroska", .extensions = "mka", .priv_data_size = sizeof(MatroskaMuxContext), #if CONFIG_LIBVORBIS_ENCODER .audio_codec = CODEC_ID_VORBIS, #else .audio_codec = CODEC_ID_AC3, #endif .video_codec = CODEC_ID_NONE, .write_header = mkv_write_header, .write_packet = mkv_write_packet, .write_trailer = mkv_write_trailer, .flags = AVFMT_GLOBALHEADER, }; #endif