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
27 typedef struct MatroskaMuxContext {
33 static void put_ebml_id(ByteIOContext *pb, unsigned int id)
36 put_byte(pb, id >> 24);
38 put_byte(pb, id >> 16);
40 put_byte(pb, id >> 8);
44 // XXX: test this thoroughly and get rid of minbytes hack (currently needed to
45 // use up all of the space reserved in start_ebml_master)
46 static void put_ebml_size(ByteIOContext *pb, uint64_t size, int minbytes)
50 // sizes larger than this are currently undefined in EBML
51 // so write "unknown" size
52 size = FFMIN(size, (1ULL<<56)-1);
54 while (size >> (bytes*7 + 7)) bytes++;
56 put_byte(pb, (0x80 >> bytes) | (size >> bytes*8));
57 for (bytes -= 1; bytes >= 0; bytes--)
58 put_byte(pb, size >> bytes*8);
61 static void put_ebml_uint(ByteIOContext *pb, unsigned int elementid, uint64_t val)
64 while (val >> bytes*8) bytes++;
66 put_ebml_id(pb, elementid);
67 put_ebml_size(pb, bytes, 0);
68 for (bytes -= 1; bytes >= 0; bytes--)
69 put_byte(pb, val >> bytes*8);
72 static void put_ebml_float(ByteIOContext *pb, unsigned int elementid, double val)
74 // XXX: single-precision floats?
75 put_ebml_id(pb, elementid);
76 put_ebml_size(pb, 8, 0);
77 put_be64(pb, av_dbl2int(val));
80 static void put_ebml_binary(ByteIOContext *pb, unsigned int elementid,
81 const uint8_t *buf, int size)
83 put_ebml_id(pb, elementid);
84 put_ebml_size(pb, size, 0);
85 put_buffer(pb, buf, size);
88 static void put_ebml_string(ByteIOContext *pb, unsigned int elementid, const char *str)
90 put_ebml_binary(pb, elementid, str, strlen(str));
93 static offset_t start_ebml_master(ByteIOContext *pb, unsigned int elementid)
95 put_ebml_id(pb, elementid);
96 // XXX: this always reserves the maximum needed space to store any size value
97 // we should be smarter (additional parameter for expected size?)
98 put_ebml_size(pb, (1ULL<<56)-1, 0); // largest unknown size
102 static void end_ebml_master(ByteIOContext *pb, offset_t start)
104 offset_t pos = url_ftell(pb);
106 url_fseek(pb, start - 8, SEEK_SET);
107 put_ebml_size(pb, pos - start, 7);
108 url_fseek(pb, pos, SEEK_SET);
112 static int mkv_write_header(AVFormatContext *s)
114 MatroskaMuxContext *mkv = s->priv_data;
115 ByteIOContext *pb = &s->pb;
116 offset_t ebml_header, segment_info, tracks;
119 ebml_header = start_ebml_master(pb, EBML_ID_HEADER);
120 put_ebml_uint (pb, EBML_ID_EBMLVERSION , 1);
121 put_ebml_uint (pb, EBML_ID_EBMLREADVERSION , 1);
122 put_ebml_uint (pb, EBML_ID_EBMLMAXIDLENGTH , 4);
123 put_ebml_uint (pb, EBML_ID_EBMLMAXSIZELENGTH , 8);
124 put_ebml_string (pb, EBML_ID_DOCTYPE , "matroska");
125 put_ebml_uint (pb, EBML_ID_DOCTYPEVERSION , 2);
126 put_ebml_uint (pb, EBML_ID_DOCTYPEREADVERSION , 2);
127 end_ebml_master(pb, ebml_header);
129 mkv->segment = start_ebml_master(pb, MATROSKA_ID_SEGMENT);
131 segment_info = start_ebml_master(pb, MATROSKA_ID_INFO);
132 put_ebml_uint(pb, MATROSKA_ID_TIMECODESCALE, 1000000);
133 if (strlen(s->title))
134 put_ebml_string(pb, MATROSKA_ID_TITLE, s->title);
135 if (!(s->streams[0]->codec->flags & CODEC_FLAG_BITEXACT)) {
136 put_ebml_string(pb, MATROSKA_ID_MUXINGAPP, LIBAVFORMAT_IDENT);
137 // XXX: both are required; something better for writing app?
138 put_ebml_string(pb, MATROSKA_ID_WRITINGAPP, LIBAVFORMAT_IDENT);
140 // XXX: segment UID and duration
141 end_ebml_master(pb, segment_info);
143 tracks = start_ebml_master(pb, MATROSKA_ID_TRACKS);
144 for (i = 0; i < s->nb_streams; i++) {
145 AVStream *st = s->streams[i];
146 AVCodecContext *codec = st->codec;
147 offset_t subinfo, track;
150 track = start_ebml_master(pb, MATROSKA_ID_TRACKENTRY);
151 put_ebml_uint (pb, MATROSKA_ID_TRACKNUMBER , i + 1);
152 put_ebml_uint (pb, MATROSKA_ID_TRACKUID , i + 1);
153 put_ebml_uint (pb, MATROSKA_ID_TRACKFLAGLACING , 0); // no lacing (yet)
156 put_ebml_string(pb, MATROSKA_ID_TRACKLANGUAGE, st->language);
158 // look for a codec id string specific to mkv to use, if none are found, use AVI codes
159 for (j = 0; ff_mkv_codec_tags[j].id != CODEC_ID_NONE; j++) {
160 if (ff_mkv_codec_tags[j].id == codec->codec_id) {
161 put_ebml_string(pb, MATROSKA_ID_CODECID, ff_mkv_codec_tags[j].str);
167 // XXX: CodecPrivate for vorbis, theora, aac, native mpeg4, ...
169 offset_t codecprivate;
171 if (codec->codec_id == CODEC_ID_VORBIS || codec->codec_id == CODEC_ID_THEORA) {
172 uint8_t *header_start[3];
174 int first_header_size;
176 if (codec->codec_id == CODEC_ID_VORBIS)
177 first_header_size = 30;
179 first_header_size = 42;
181 if (ff_split_xiph_headers(codec->extradata, codec->extradata_size,
182 first_header_size, header_start, header_len) < 0) {
183 av_log(s, AV_LOG_ERROR, "Extradata corrupt.\n");
187 codecprivate = start_ebml_master(pb, MATROSKA_ID_CODECPRIVATE);
188 put_byte(pb, 2); // number packets - 1
189 for (j = 0; j < 2; j++) {
190 for (k = 0; k < header_len[j] / 255; k++)
192 put_byte(pb, header_len[j] % 255);
194 for (j = 0; j < 3; j++)
195 put_buffer(pb, header_start[j], header_len[j]);
196 end_ebml_master(pb, codecprivate);
198 put_ebml_binary(pb, MATROSKA_ID_CODECPRIVATE, codec->extradata, codec->extradata_size);
202 switch (codec->codec_type) {
203 case CODEC_TYPE_VIDEO:
204 put_ebml_uint(pb, MATROSKA_ID_TRACKTYPE, MATROSKA_TRACK_TYPE_VIDEO);
208 // if there is no mkv-specific codec id, use VFW mode
209 if (!codec->codec_tag)
210 codec->codec_tag = codec_get_tag(codec_bmp_tags, codec->codec_id);
212 put_ebml_string(pb, MATROSKA_ID_CODECID, MATROSKA_CODEC_ID_VIDEO_VFW_FOURCC);
213 // XXX: codec private isn't a master; is there a better way to re-use put_bmp_header?
214 bmp_header = start_ebml_master(pb, MATROSKA_ID_CODECPRIVATE);
215 put_bmp_header(pb, codec, codec_bmp_tags, 0);
216 end_ebml_master(pb, bmp_header);
218 subinfo = start_ebml_master(pb, MATROSKA_ID_TRACKVIDEO);
219 // XXX: interlace flag?
220 put_ebml_uint (pb, MATROSKA_ID_VIDEOPIXELWIDTH , codec->width);
221 put_ebml_uint (pb, MATROSKA_ID_VIDEOPIXELHEIGHT, codec->height);
222 // XXX: display width/height
223 end_ebml_master(pb, subinfo);
226 case CODEC_TYPE_AUDIO:
227 put_ebml_uint(pb, MATROSKA_ID_TRACKTYPE, MATROSKA_TRACK_TYPE_AUDIO);
230 subinfo = start_ebml_master(pb, MATROSKA_ID_TRACKAUDIO);
231 put_ebml_uint (pb, MATROSKA_ID_AUDIOCHANNELS , codec->channels);
232 put_ebml_float (pb, MATROSKA_ID_AUDIOSAMPLINGFREQ, codec->sample_rate);
233 // XXX: output sample freq (for sbr) and bitdepth (for pcm)
234 end_ebml_master(pb, subinfo);
238 av_log(s, AV_LOG_ERROR, "Only audio and video are supported for Matroska.");
241 end_ebml_master(pb, track);
243 // ms precision is the de-facto standard timescale for mkv files
244 av_set_pts_info(st, 64, 1, 1000);
246 end_ebml_master(pb, tracks);
248 mkv->cluster = start_ebml_master(pb, MATROSKA_ID_CLUSTER);
249 put_ebml_uint(pb, MATROSKA_ID_CLUSTERTIMECODE, 0);
250 mkv->cluster_pts = 0;
255 static int mkv_write_packet(AVFormatContext *s, AVPacket *pkt)
257 MatroskaMuxContext *mkv = s->priv_data;
258 ByteIOContext *pb = &s->pb;
261 // start a new cluster every 5 MB or 5 sec
262 if (url_ftell(pb) > mkv->cluster + 5*1024*1024 || pkt->pts > mkv->cluster_pts + 5000) {
263 end_ebml_master(pb, mkv->cluster);
264 mkv->cluster = start_ebml_master(pb, MATROSKA_ID_CLUSTER);
265 put_ebml_uint(pb, MATROSKA_ID_CLUSTERTIMECODE, pkt->pts);
266 mkv->cluster_pts = pkt->pts;
269 block = start_ebml_master(pb, MATROSKA_ID_SIMPLEBLOCK);
270 put_byte(pb, 0x80 | (pkt->stream_index + 1)); // this assumes stream_index is less than 126
271 put_be16(pb, pkt->pts - mkv->cluster_pts);
272 put_byte(pb, !!(pkt->flags & PKT_FLAG_KEY));
273 put_buffer(pb, pkt->data, pkt->size);
274 end_ebml_master(pb, block);
278 static int mkv_write_trailer(AVFormatContext *s)
280 MatroskaMuxContext *mkv = s->priv_data;
281 ByteIOContext *pb = &s->pb;
282 end_ebml_master(pb, mkv->cluster);
283 end_ebml_master(pb, mkv->segment);
287 AVOutputFormat matroska_muxer = {
289 "Matroska File Format",
292 sizeof(MatroskaMuxContext),
298 .codec_tag = (const AVCodecTag*[]){codec_bmp_tags, codec_wav_tags, 0},