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ffmpeg / libavformat / matroskaenc.c @ 72415b2a

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1
/*
2
 * Matroska muxer
3
 * Copyright (c) 2007 David Conrad
4
 *
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 * This file is part of FFmpeg.
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 *
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 * FFmpeg is free software; you can redistribute it and/or
8
 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
10
 * version 2.1 of the License, or (at your option) any later version.
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 *
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 * FFmpeg is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15
 * Lesser General Public License for more details.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with FFmpeg; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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 */
21

    
22
#include "avformat.h"
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#include "riff.h"
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#include "isom.h"
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#include "matroska.h"
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#include "avc.h"
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#include "flacenc.h"
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#include "libavutil/intreadwrite.h"
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#include "libavutil/md5.h"
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#include "libavcodec/xiph.h"
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#include "libavcodec/mpeg4audio.h"
32

    
33
typedef struct ebml_master {
34
    int64_t         pos;                ///< absolute offset in the file where the master's elements start
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    int             sizebytes;          ///< how many bytes were reserved for the size
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} ebml_master;
37

    
38
typedef struct mkv_seekhead_entry {
39
    unsigned int    elementid;
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    uint64_t        segmentpos;
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} mkv_seekhead_entry;
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43
typedef struct mkv_seekhead {
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    int64_t                 filepos;
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    int64_t                 segment_offset;     ///< the file offset to the beginning of the segment
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    int                     reserved_size;      ///< -1 if appending to file
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    int                     max_entries;
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    mkv_seekhead_entry      *entries;
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    int                     num_entries;
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} mkv_seekhead;
51

    
52
typedef struct {
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    uint64_t        pts;
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    int             tracknum;
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    int64_t         cluster_pos;        ///< file offset of the cluster containing the block
56
} mkv_cuepoint;
57

    
58
typedef struct {
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    int64_t         segment_offset;
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    mkv_cuepoint    *entries;
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    int             num_entries;
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} mkv_cues;
63

    
64
typedef struct {
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    int             write_dts;
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} mkv_track;
67

    
68
typedef struct MatroskaMuxContext {
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    ByteIOContext   *dyn_bc;
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    ebml_master     segment;
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    int64_t         segment_offset;
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    int64_t         segment_uid;
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    ebml_master     cluster;
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    int64_t         cluster_pos;        ///< file offset of the current cluster
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    int64_t         cluster_pts;
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    int64_t         duration_offset;
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    int64_t         duration;
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    mkv_seekhead    *main_seekhead;
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    mkv_seekhead    *cluster_seekhead;
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    mkv_cues        *cues;
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    mkv_track       *tracks;
82

    
83
    struct AVMD5    *md5_ctx;
84
} MatroskaMuxContext;
85

    
86

    
87
/** 2 bytes * 3 for EBML IDs, 3 1-byte EBML lengths, 8 bytes for 64 bit
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 * offset, 4 bytes for target EBML ID */
89
#define MAX_SEEKENTRY_SIZE 21
90

    
91
/** per-cuepoint-track - 3 1-byte EBML IDs, 3 1-byte EBML sizes, 2
92
 * 8-byte uint max */
93
#define MAX_CUETRACKPOS_SIZE 22
94

    
95
/** per-cuepoint - 2 1-byte EBML IDs, 2 1-byte EBML sizes, 8-byte uint max */
96
#define MAX_CUEPOINT_SIZE(num_tracks) 12 + MAX_CUETRACKPOS_SIZE*num_tracks
97

    
98

    
99
static int ebml_id_size(unsigned int id)
100
{
101
    return (av_log2(id+1)-1)/7+1;
102
}
103

    
104
static void put_ebml_id(ByteIOContext *pb, unsigned int id)
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{
106
    int i = ebml_id_size(id);
107
    while (i--)
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        put_byte(pb, id >> (i*8));
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}
110

    
111
/**
112
 * Write an EBML size meaning "unknown size".
113
 *
114
 * @param bytes The number of bytes the size should occupy (maximum: 8).
115
 */
116
static void put_ebml_size_unknown(ByteIOContext *pb, int bytes)
117
{
118
    assert(bytes <= 8);
119
    put_byte(pb, 0x1ff >> bytes);
120
    while (--bytes)
121
        put_byte(pb, 0xff);
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}
123

    
124
/**
125
 * Calculate how many bytes are needed to represent a given number in EBML.
126
 */
127
static int ebml_num_size(uint64_t num)
128
{
129
    int bytes = 1;
130
    while ((num+1) >> bytes*7) bytes++;
131
    return bytes;
132
}
133

    
134
/**
135
 * Write a number in EBML variable length format.
136
 *
137
 * @param bytes The number of bytes that need to be used to write the number.
138
 *              If zero, any number of bytes can be used.
139
 */
140
static void put_ebml_num(ByteIOContext *pb, uint64_t num, int bytes)
141
{
142
    int i, needed_bytes = ebml_num_size(num);
143

    
144
    // sizes larger than this are currently undefined in EBML
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    assert(num < (1ULL<<56)-1);
146

    
147
    if (bytes == 0)
148
        // don't care how many bytes are used, so use the min
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        bytes = needed_bytes;
150
    // the bytes needed to write the given size would exceed the bytes
151
    // that we need to use, so write unknown size. This shouldn't happen.
152
    assert(bytes >= needed_bytes);
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154
    num |= 1ULL << bytes*7;
155
    for (i = bytes - 1; i >= 0; i--)
156
        put_byte(pb, num >> i*8);
157
}
158

    
159
static void put_ebml_uint(ByteIOContext *pb, unsigned int elementid, uint64_t val)
160
{
161
    int i, bytes = 1;
162
    uint64_t tmp = val;
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    while (tmp>>=8) bytes++;
164

    
165
    put_ebml_id(pb, elementid);
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    put_ebml_num(pb, bytes, 0);
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    for (i = bytes - 1; i >= 0; i--)
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        put_byte(pb, val >> i*8);
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}
170

    
171
static void put_ebml_float(ByteIOContext *pb, unsigned int elementid, double val)
172
{
173
    put_ebml_id(pb, elementid);
174
    put_ebml_num(pb, 8, 0);
175
    put_be64(pb, av_dbl2int(val));
176
}
177

    
178
static void put_ebml_binary(ByteIOContext *pb, unsigned int elementid,
179
                            const uint8_t *buf, int size)
180
{
181
    put_ebml_id(pb, elementid);
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    put_ebml_num(pb, size, 0);
183
    put_buffer(pb, buf, size);
184
}
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186
static void put_ebml_string(ByteIOContext *pb, unsigned int elementid, const char *str)
187
{
188
    put_ebml_binary(pb, elementid, str, strlen(str));
189
}
190

    
191
/**
192
 * Writes a void element of a given size. Useful for reserving space in
193
 * the file to be written to later.
194
 *
195
 * @param size The number of bytes to reserve, which must be at least 2.
196
 */
197
static void put_ebml_void(ByteIOContext *pb, uint64_t size)
198
{
199
    int64_t currentpos = url_ftell(pb);
200

    
201
    assert(size >= 2);
202

    
203
    put_ebml_id(pb, EBML_ID_VOID);
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    // we need to subtract the length needed to store the size from the
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    // size we need to reserve so 2 cases, we use 8 bytes to store the
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    // size if possible, 1 byte otherwise
207
    if (size < 10)
208
        put_ebml_num(pb, size-1, 0);
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    else
210
        put_ebml_num(pb, size-9, 8);
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    while(url_ftell(pb) < currentpos + size)
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        put_byte(pb, 0);
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}
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static ebml_master start_ebml_master(ByteIOContext *pb, unsigned int elementid, uint64_t expectedsize)
216
{
217
    int bytes = expectedsize ? ebml_num_size(expectedsize) : 8;
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    put_ebml_id(pb, elementid);
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    put_ebml_size_unknown(pb, bytes);
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    return (ebml_master){ url_ftell(pb), bytes };
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}
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static void end_ebml_master(ByteIOContext *pb, ebml_master master)
224
{
225
    int64_t pos = url_ftell(pb);
226

    
227
    if (url_fseek(pb, master.pos - master.sizebytes, SEEK_SET) < 0)
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        return;
229
    put_ebml_num(pb, pos - master.pos, master.sizebytes);
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    url_fseek(pb, pos, SEEK_SET);
231
}
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233
static void put_xiph_size(ByteIOContext *pb, int size)
234
{
235
    int i;
236
    for (i = 0; i < size / 255; i++)
237
        put_byte(pb, 255);
238
    put_byte(pb, size % 255);
239
}
240

    
241
/**
242
 * Initialize a mkv_seekhead element to be ready to index level 1 Matroska
243
 * elements. If a maximum number of elements is specified, enough space
244
 * will be reserved at the current file location to write a seek head of
245
 * that size.
246
 *
247
 * @param segment_offset The absolute offset to the position in the file
248
 *                       where the segment begins.
249
 * @param numelements The maximum number of elements that will be indexed
250
 *                    by this seek head, 0 if unlimited.
251
 */
252
static mkv_seekhead * mkv_start_seekhead(ByteIOContext *pb, int64_t segment_offset, int numelements)
253
{
254
    mkv_seekhead *new_seekhead = av_mallocz(sizeof(mkv_seekhead));
255
    if (new_seekhead == NULL)
256
        return NULL;
257

    
258
    new_seekhead->segment_offset = segment_offset;
259

    
260
    if (numelements > 0) {
261
        new_seekhead->filepos = url_ftell(pb);
262
        // 21 bytes max for a seek entry, 10 bytes max for the SeekHead ID
263
        // and size, and 3 bytes to guarantee that an EBML void element
264
        // will fit afterwards
265
        new_seekhead->reserved_size = numelements * MAX_SEEKENTRY_SIZE + 13;
266
        new_seekhead->max_entries = numelements;
267
        put_ebml_void(pb, new_seekhead->reserved_size);
268
    }
269
    return new_seekhead;
270
}
271

    
272
static int mkv_add_seekhead_entry(mkv_seekhead *seekhead, unsigned int elementid, uint64_t filepos)
273
{
274
    mkv_seekhead_entry *entries = seekhead->entries;
275

    
276
    // don't store more elements than we reserved space for
277
    if (seekhead->max_entries > 0 && seekhead->max_entries <= seekhead->num_entries)
278
        return -1;
279

    
280
    entries = av_realloc(entries, (seekhead->num_entries + 1) * sizeof(mkv_seekhead_entry));
281
    if (entries == NULL)
282
        return AVERROR(ENOMEM);
283

    
284
    entries[seekhead->num_entries  ].elementid = elementid;
285
    entries[seekhead->num_entries++].segmentpos = filepos - seekhead->segment_offset;
286

    
287
    seekhead->entries = entries;
288
    return 0;
289
}
290

    
291
/**
292
 * Write the seek head to the file and free it. If a maximum number of
293
 * elements was specified to mkv_start_seekhead(), the seek head will
294
 * be written at the location reserved for it. Otherwise, it is written
295
 * at the current location in the file.
296
 *
297
 * @return The file offset where the seekhead was written,
298
 * -1 if an error occurred.
299
 */
300
static int64_t mkv_write_seekhead(ByteIOContext *pb, mkv_seekhead *seekhead)
301
{
302
    ebml_master metaseek, seekentry;
303
    int64_t currentpos;
304
    int i;
305

    
306
    currentpos = url_ftell(pb);
307

    
308
    if (seekhead->reserved_size > 0)
309
        if (url_fseek(pb, seekhead->filepos, SEEK_SET) < 0)
310
            return -1;
311

    
312
    metaseek = start_ebml_master(pb, MATROSKA_ID_SEEKHEAD, seekhead->reserved_size);
313
    for (i = 0; i < seekhead->num_entries; i++) {
314
        mkv_seekhead_entry *entry = &seekhead->entries[i];
315

    
316
        seekentry = start_ebml_master(pb, MATROSKA_ID_SEEKENTRY, MAX_SEEKENTRY_SIZE);
317

    
318
        put_ebml_id(pb, MATROSKA_ID_SEEKID);
319
        put_ebml_num(pb, ebml_id_size(entry->elementid), 0);
320
        put_ebml_id(pb, entry->elementid);
321

    
322
        put_ebml_uint(pb, MATROSKA_ID_SEEKPOSITION, entry->segmentpos);
323
        end_ebml_master(pb, seekentry);
324
    }
325
    end_ebml_master(pb, metaseek);
326

    
327
    if (seekhead->reserved_size > 0) {
328
        uint64_t remaining = seekhead->filepos + seekhead->reserved_size - url_ftell(pb);
329
        put_ebml_void(pb, remaining);
330
        url_fseek(pb, currentpos, SEEK_SET);
331

    
332
        currentpos = seekhead->filepos;
333
    }
334
    av_free(seekhead->entries);
335
    av_free(seekhead);
336

    
337
    return currentpos;
338
}
339

    
340
static mkv_cues * mkv_start_cues(int64_t segment_offset)
341
{
342
    mkv_cues *cues = av_mallocz(sizeof(mkv_cues));
343
    if (cues == NULL)
344
        return NULL;
345

    
346
    cues->segment_offset = segment_offset;
347
    return cues;
348
}
349

    
350
static int mkv_add_cuepoint(mkv_cues *cues, int stream, int64_t ts, int64_t cluster_pos)
351
{
352
    mkv_cuepoint *entries = cues->entries;
353

    
354
    entries = av_realloc(entries, (cues->num_entries + 1) * sizeof(mkv_cuepoint));
355
    if (entries == NULL)
356
        return AVERROR(ENOMEM);
357

    
358
    if (ts < 0)
359
        return 0;
360

    
361
    entries[cues->num_entries  ].pts = ts;
362
    entries[cues->num_entries  ].tracknum = stream + 1;
363
    entries[cues->num_entries++].cluster_pos = cluster_pos - cues->segment_offset;
364

    
365
    cues->entries = entries;
366
    return 0;
367
}
368

    
369
static int64_t mkv_write_cues(ByteIOContext *pb, mkv_cues *cues, int num_tracks)
370
{
371
    ebml_master cues_element;
372
    int64_t currentpos;
373
    int i, j;
374

    
375
    currentpos = url_ftell(pb);
376
    cues_element = start_ebml_master(pb, MATROSKA_ID_CUES, 0);
377

    
378
    for (i = 0; i < cues->num_entries; i++) {
379
        ebml_master cuepoint, track_positions;
380
        mkv_cuepoint *entry = &cues->entries[i];
381
        uint64_t pts = entry->pts;
382

    
383
        cuepoint = start_ebml_master(pb, MATROSKA_ID_POINTENTRY, MAX_CUEPOINT_SIZE(num_tracks));
384
        put_ebml_uint(pb, MATROSKA_ID_CUETIME, pts);
385

    
386
        // put all the entries from different tracks that have the exact same
387
        // timestamp into the same CuePoint
388
        for (j = 0; j < cues->num_entries - i && entry[j].pts == pts; j++) {
389
            track_positions = start_ebml_master(pb, MATROSKA_ID_CUETRACKPOSITION, MAX_CUETRACKPOS_SIZE);
390
            put_ebml_uint(pb, MATROSKA_ID_CUETRACK          , entry[j].tracknum   );
391
            put_ebml_uint(pb, MATROSKA_ID_CUECLUSTERPOSITION, entry[j].cluster_pos);
392
            end_ebml_master(pb, track_positions);
393
        }
394
        i += j - 1;
395
        end_ebml_master(pb, cuepoint);
396
    }
397
    end_ebml_master(pb, cues_element);
398

    
399
    av_free(cues->entries);
400
    av_free(cues);
401
    return currentpos;
402
}
403

    
404
static int put_xiph_codecpriv(AVFormatContext *s, ByteIOContext *pb, AVCodecContext *codec)
405
{
406
    uint8_t *header_start[3];
407
    int header_len[3];
408
    int first_header_size;
409
    int j;
410

    
411
    if (codec->codec_id == CODEC_ID_VORBIS)
412
        first_header_size = 30;
413
    else
414
        first_header_size = 42;
415

    
416
    if (ff_split_xiph_headers(codec->extradata, codec->extradata_size,
417
                              first_header_size, header_start, header_len) < 0) {
418
        av_log(s, AV_LOG_ERROR, "Extradata corrupt.\n");
419
        return -1;
420
    }
421

    
422
    put_byte(pb, 2);                    // number packets - 1
423
    for (j = 0; j < 2; j++) {
424
        put_xiph_size(pb, header_len[j]);
425
    }
426
    for (j = 0; j < 3; j++)
427
        put_buffer(pb, header_start[j], header_len[j]);
428

    
429
    return 0;
430
}
431

    
432
static void get_aac_sample_rates(AVFormatContext *s, AVCodecContext *codec, int *sample_rate, int *output_sample_rate)
433
{
434
    int sri;
435

    
436
    if (codec->extradata_size < 2) {
437
        av_log(s, AV_LOG_WARNING, "No AAC extradata, unable to determine samplerate.\n");
438
        return;
439
    }
440

    
441
    sri = ((codec->extradata[0] << 1) & 0xE) | (codec->extradata[1] >> 7);
442
    if (sri > 12) {
443
        av_log(s, AV_LOG_WARNING, "AAC samplerate index out of bounds\n");
444
        return;
445
    }
446
    *sample_rate = ff_mpeg4audio_sample_rates[sri];
447

    
448
    // if sbr, get output sample rate as well
449
    if (codec->extradata_size == 5) {
450
        sri = (codec->extradata[4] >> 3) & 0xF;
451
        if (sri > 12) {
452
            av_log(s, AV_LOG_WARNING, "AAC output samplerate index out of bounds\n");
453
            return;
454
        }
455
        *output_sample_rate = ff_mpeg4audio_sample_rates[sri];
456
    }
457
}
458

    
459
static int mkv_write_codecprivate(AVFormatContext *s, ByteIOContext *pb, AVCodecContext *codec, int native_id, int qt_id)
460
{
461
    ByteIOContext *dyn_cp;
462
    uint8_t *codecpriv;
463
    int ret, codecpriv_size;
464

    
465
    ret = url_open_dyn_buf(&dyn_cp);
466
    if(ret < 0)
467
        return ret;
468

    
469
    if (native_id) {
470
        if (codec->codec_id == CODEC_ID_VORBIS || codec->codec_id == CODEC_ID_THEORA)
471
            ret = put_xiph_codecpriv(s, dyn_cp, codec);
472
        else if (codec->codec_id == CODEC_ID_FLAC)
473
            ret = ff_flac_write_header(dyn_cp, codec, 1);
474
        else if (codec->codec_id == CODEC_ID_H264)
475
            ret = ff_isom_write_avcc(dyn_cp, codec->extradata, codec->extradata_size);
476
        else if (codec->extradata_size)
477
            put_buffer(dyn_cp, codec->extradata, codec->extradata_size);
478
    } else if (codec->codec_type == AVMEDIA_TYPE_VIDEO) {
479
        if (qt_id) {
480
            if (!codec->codec_tag)
481
                codec->codec_tag = ff_codec_get_tag(codec_movvideo_tags, codec->codec_id);
482
            if (codec->extradata_size)
483
                put_buffer(dyn_cp, codec->extradata, codec->extradata_size);
484
        } else {
485
            if (!codec->codec_tag)
486
                codec->codec_tag = ff_codec_get_tag(ff_codec_bmp_tags, codec->codec_id);
487
            if (!codec->codec_tag) {
488
                av_log(s, AV_LOG_ERROR, "No bmp codec ID found.\n");
489
                ret = -1;
490
            }
491

    
492
            ff_put_bmp_header(dyn_cp, codec, ff_codec_bmp_tags, 0);
493
        }
494

    
495
    } else if (codec->codec_type == AVMEDIA_TYPE_AUDIO) {
496
        unsigned int tag;
497
        tag = ff_codec_get_tag(ff_codec_wav_tags, codec->codec_id);
498
        if (!tag) {
499
            av_log(s, AV_LOG_ERROR, "No wav codec ID found.\n");
500
            ret = -1;
501
        }
502
        if (!codec->codec_tag)
503
            codec->codec_tag = tag;
504

    
505
        ff_put_wav_header(dyn_cp, codec);
506
    }
507

    
508
    codecpriv_size = url_close_dyn_buf(dyn_cp, &codecpriv);
509
    if (codecpriv_size)
510
        put_ebml_binary(pb, MATROSKA_ID_CODECPRIVATE, codecpriv, codecpriv_size);
511
    av_free(codecpriv);
512
    return ret;
513
}
514

    
515
static int mkv_write_tracks(AVFormatContext *s)
516
{
517
    MatroskaMuxContext *mkv = s->priv_data;
518
    ByteIOContext *pb = s->pb;
519
    ebml_master tracks;
520
    int i, j, ret;
521

    
522
    ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_TRACKS, url_ftell(pb));
523
    if (ret < 0) return ret;
524

    
525
    tracks = start_ebml_master(pb, MATROSKA_ID_TRACKS, 0);
526
    for (i = 0; i < s->nb_streams; i++) {
527
        AVStream *st = s->streams[i];
528
        AVCodecContext *codec = st->codec;
529
        ebml_master subinfo, track;
530
        int native_id = 0;
531
        int qt_id = 0;
532
        int bit_depth = av_get_bits_per_sample(codec->codec_id);
533
        int sample_rate = codec->sample_rate;
534
        int output_sample_rate = 0;
535
        AVMetadataTag *tag;
536

    
537
        if (!bit_depth)
538
            bit_depth = av_get_bits_per_sample_format(codec->sample_fmt);
539

    
540
        if (codec->codec_id == CODEC_ID_AAC)
541
            get_aac_sample_rates(s, codec, &sample_rate, &output_sample_rate);
542

    
543
        track = start_ebml_master(pb, MATROSKA_ID_TRACKENTRY, 0);
544
        put_ebml_uint (pb, MATROSKA_ID_TRACKNUMBER     , i + 1);
545
        put_ebml_uint (pb, MATROSKA_ID_TRACKUID        , i + 1);
546
        put_ebml_uint (pb, MATROSKA_ID_TRACKFLAGLACING , 0);    // no lacing (yet)
547
        put_ebml_float(pb, MATROSKA_ID_TRACKTIMECODESCALE, 1.0);
548

    
549
        if ((tag = av_metadata_get(st->metadata, "title", NULL, 0)))
550
            put_ebml_string(pb, MATROSKA_ID_TRACKNAME, tag->value);
551
        tag = av_metadata_get(st->metadata, "language", NULL, 0);
552
        put_ebml_string(pb, MATROSKA_ID_TRACKLANGUAGE, tag ? tag->value:"und");
553

    
554
        if (st->disposition)
555
            put_ebml_uint(pb, MATROSKA_ID_TRACKFLAGDEFAULT, !!(st->disposition & AV_DISPOSITION_DEFAULT));
556

    
557
        // look for a codec ID string specific to mkv to use,
558
        // if none are found, use AVI codes
559
        for (j = 0; ff_mkv_codec_tags[j].id != CODEC_ID_NONE; j++) {
560
            if (ff_mkv_codec_tags[j].id == codec->codec_id) {
561
                put_ebml_string(pb, MATROSKA_ID_CODECID, ff_mkv_codec_tags[j].str);
562
                native_id = 1;
563
                break;
564
            }
565
        }
566

    
567
        switch (codec->codec_type) {
568
            case AVMEDIA_TYPE_VIDEO:
569
                put_ebml_uint(pb, MATROSKA_ID_TRACKTYPE, MATROSKA_TRACK_TYPE_VIDEO);
570

    
571
                if (!native_id &&
572
                      ff_codec_get_tag(codec_movvideo_tags, codec->codec_id) &&
573
                    (!ff_codec_get_tag(ff_codec_bmp_tags,   codec->codec_id)
574
                     || codec->codec_id == CODEC_ID_SVQ1
575
                     || codec->codec_id == CODEC_ID_SVQ3
576
                     || codec->codec_id == CODEC_ID_CINEPAK))
577
                    qt_id = 1;
578

    
579
                if (qt_id)
580
                    put_ebml_string(pb, MATROSKA_ID_CODECID, "V_QUICKTIME");
581
                else if (!native_id) {
582
                    // if there is no mkv-specific codec ID, use VFW mode
583
                    put_ebml_string(pb, MATROSKA_ID_CODECID, "V_MS/VFW/FOURCC");
584
                    mkv->tracks[i].write_dts = 1;
585
                }
586

    
587
                subinfo = start_ebml_master(pb, MATROSKA_ID_TRACKVIDEO, 0);
588
                // XXX: interlace flag?
589
                put_ebml_uint (pb, MATROSKA_ID_VIDEOPIXELWIDTH , codec->width);
590
                put_ebml_uint (pb, MATROSKA_ID_VIDEOPIXELHEIGHT, codec->height);
591
                if (st->sample_aspect_ratio.num) {
592
                    int d_width = codec->width*av_q2d(st->sample_aspect_ratio);
593
                    put_ebml_uint(pb, MATROSKA_ID_VIDEODISPLAYWIDTH , d_width);
594
                    put_ebml_uint(pb, MATROSKA_ID_VIDEODISPLAYHEIGHT, codec->height);
595
                }
596
                end_ebml_master(pb, subinfo);
597
                break;
598

    
599
            case AVMEDIA_TYPE_AUDIO:
600
                put_ebml_uint(pb, MATROSKA_ID_TRACKTYPE, MATROSKA_TRACK_TYPE_AUDIO);
601

    
602
                if (!native_id)
603
                    // no mkv-specific ID, use ACM mode
604
                    put_ebml_string(pb, MATROSKA_ID_CODECID, "A_MS/ACM");
605

    
606
                subinfo = start_ebml_master(pb, MATROSKA_ID_TRACKAUDIO, 0);
607
                put_ebml_uint  (pb, MATROSKA_ID_AUDIOCHANNELS    , codec->channels);
608
                put_ebml_float (pb, MATROSKA_ID_AUDIOSAMPLINGFREQ, sample_rate);
609
                if (output_sample_rate)
610
                    put_ebml_float(pb, MATROSKA_ID_AUDIOOUTSAMPLINGFREQ, output_sample_rate);
611
                if (bit_depth)
612
                    put_ebml_uint(pb, MATROSKA_ID_AUDIOBITDEPTH, bit_depth);
613
                end_ebml_master(pb, subinfo);
614
                break;
615

    
616
            case AVMEDIA_TYPE_SUBTITLE:
617
                put_ebml_uint(pb, MATROSKA_ID_TRACKTYPE, MATROSKA_TRACK_TYPE_SUBTITLE);
618
                break;
619
            default:
620
                av_log(s, AV_LOG_ERROR, "Only audio, video, and subtitles are supported for Matroska.");
621
                break;
622
        }
623
        ret = mkv_write_codecprivate(s, pb, codec, native_id, qt_id);
624
        if (ret < 0) return ret;
625

    
626
        end_ebml_master(pb, track);
627

    
628
        // ms precision is the de-facto standard timescale for mkv files
629
        av_set_pts_info(st, 64, 1, 1000);
630
    }
631
    end_ebml_master(pb, tracks);
632
    return 0;
633
}
634

    
635
static int mkv_write_chapters(AVFormatContext *s)
636
{
637
    MatroskaMuxContext *mkv = s->priv_data;
638
    ByteIOContext *pb = s->pb;
639
    ebml_master chapters, editionentry;
640
    AVRational scale = {1, 1E9};
641
    int i, ret;
642

    
643
    if (!s->nb_chapters)
644
        return 0;
645

    
646
    ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_CHAPTERS, url_ftell(pb));
647
    if (ret < 0) return ret;
648

    
649
    chapters     = start_ebml_master(pb, MATROSKA_ID_CHAPTERS    , 0);
650
    editionentry = start_ebml_master(pb, MATROSKA_ID_EDITIONENTRY, 0);
651
    put_ebml_uint(pb, MATROSKA_ID_EDITIONFLAGDEFAULT, 1);
652
    put_ebml_uint(pb, MATROSKA_ID_EDITIONFLAGHIDDEN , 0);
653
    for (i = 0; i < s->nb_chapters; i++) {
654
        ebml_master chapteratom, chapterdisplay;
655
        AVChapter *c     = s->chapters[i];
656
        AVMetadataTag *t = NULL;
657

    
658
        chapteratom = start_ebml_master(pb, MATROSKA_ID_CHAPTERATOM, 0);
659
        put_ebml_uint(pb, MATROSKA_ID_CHAPTERUID, c->id);
660
        put_ebml_uint(pb, MATROSKA_ID_CHAPTERTIMESTART,
661
                      av_rescale_q(c->start, c->time_base, scale));
662
        put_ebml_uint(pb, MATROSKA_ID_CHAPTERTIMEEND,
663
                      av_rescale_q(c->end,   c->time_base, scale));
664
        put_ebml_uint(pb, MATROSKA_ID_CHAPTERFLAGHIDDEN , 0);
665
        put_ebml_uint(pb, MATROSKA_ID_CHAPTERFLAGENABLED, 1);
666
        if ((t = av_metadata_get(c->metadata, "title", NULL, 0))) {
667
            chapterdisplay = start_ebml_master(pb, MATROSKA_ID_CHAPTERDISPLAY, 0);
668
            put_ebml_string(pb, MATROSKA_ID_CHAPSTRING, t->value);
669
            put_ebml_string(pb, MATROSKA_ID_CHAPLANG  , "und");
670
            end_ebml_master(pb, chapterdisplay);
671
        }
672
        end_ebml_master(pb, chapteratom);
673
    }
674
    end_ebml_master(pb, editionentry);
675
    end_ebml_master(pb, chapters);
676
    return 0;
677
}
678

    
679
static int mkv_write_header(AVFormatContext *s)
680
{
681
    MatroskaMuxContext *mkv = s->priv_data;
682
    ByteIOContext *pb = s->pb;
683
    ebml_master ebml_header, segment_info;
684
    AVMetadataTag *tag;
685
    int ret;
686

    
687
    mkv->md5_ctx = av_mallocz(av_md5_size);
688
    av_md5_init(mkv->md5_ctx);
689
    mkv->tracks = av_mallocz(s->nb_streams * sizeof(*mkv->tracks));
690

    
691
    ebml_header = start_ebml_master(pb, EBML_ID_HEADER, 0);
692
    put_ebml_uint   (pb, EBML_ID_EBMLVERSION        ,           1);
693
    put_ebml_uint   (pb, EBML_ID_EBMLREADVERSION    ,           1);
694
    put_ebml_uint   (pb, EBML_ID_EBMLMAXIDLENGTH    ,           4);
695
    put_ebml_uint   (pb, EBML_ID_EBMLMAXSIZELENGTH  ,           8);
696
    put_ebml_string (pb, EBML_ID_DOCTYPE            ,  "matroska");
697
    put_ebml_uint   (pb, EBML_ID_DOCTYPEVERSION     ,           2);
698
    put_ebml_uint   (pb, EBML_ID_DOCTYPEREADVERSION ,           2);
699
    end_ebml_master(pb, ebml_header);
700

    
701
    mkv->segment = start_ebml_master(pb, MATROSKA_ID_SEGMENT, 0);
702
    mkv->segment_offset = url_ftell(pb);
703

    
704
    // we write 2 seek heads - one at the end of the file to point to each
705
    // cluster, and one at the beginning to point to all other level one
706
    // elements (including the seek head at the end of the file), which
707
    // isn't more than 10 elements if we only write one of each other
708
    // currently defined level 1 element
709
    mkv->main_seekhead    = mkv_start_seekhead(pb, mkv->segment_offset, 10);
710
    mkv->cluster_seekhead = mkv_start_seekhead(pb, mkv->segment_offset, 0);
711
    if (mkv->main_seekhead == NULL || mkv->cluster_seekhead == NULL)
712
        return AVERROR(ENOMEM);
713

    
714
    ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_INFO, url_ftell(pb));
715
    if (ret < 0) return ret;
716

    
717
    segment_info = start_ebml_master(pb, MATROSKA_ID_INFO, 0);
718
    put_ebml_uint(pb, MATROSKA_ID_TIMECODESCALE, 1000000);
719
    if ((tag = av_metadata_get(s->metadata, "title", NULL, 0)))
720
        put_ebml_string(pb, MATROSKA_ID_TITLE, tag->value);
721
    if (!(s->streams[0]->codec->flags & CODEC_FLAG_BITEXACT)) {
722
        put_ebml_string(pb, MATROSKA_ID_MUXINGAPP , LIBAVFORMAT_IDENT);
723
        put_ebml_string(pb, MATROSKA_ID_WRITINGAPP, LIBAVFORMAT_IDENT);
724

    
725
        // reserve space to write the segment UID later
726
        mkv->segment_uid = url_ftell(pb);
727
        put_ebml_void(pb, 19);
728
    }
729

    
730
    // reserve space for the duration
731
    mkv->duration = 0;
732
    mkv->duration_offset = url_ftell(pb);
733
    put_ebml_void(pb, 11);                  // assumes double-precision float to be written
734
    end_ebml_master(pb, segment_info);
735

    
736
    ret = mkv_write_tracks(s);
737
    if (ret < 0) return ret;
738

    
739
    ret = mkv_write_chapters(s);
740
    if (ret < 0) return ret;
741

    
742
    if (url_is_streamed(s->pb))
743
        mkv_write_seekhead(pb, mkv->main_seekhead);
744

    
745
    mkv->cues = mkv_start_cues(mkv->segment_offset);
746
    if (mkv->cues == NULL)
747
        return AVERROR(ENOMEM);
748

    
749
    put_flush_packet(pb);
750
    return 0;
751
}
752

    
753
static int mkv_blockgroup_size(int pkt_size)
754
{
755
    int size = pkt_size + 4;
756
    size += ebml_num_size(size);
757
    size += 2;              // EBML ID for block and block duration
758
    size += 8;              // max size of block duration
759
    size += ebml_num_size(size);
760
    size += 1;              // blockgroup EBML ID
761
    return size;
762
}
763

    
764
static int ass_get_duration(const uint8_t *p)
765
{
766
    int sh, sm, ss, sc, eh, em, es, ec;
767
    uint64_t start, end;
768

    
769
    if (sscanf(p, "%*[^,],%d:%d:%d%*c%d,%d:%d:%d%*c%d",
770
               &sh, &sm, &ss, &sc, &eh, &em, &es, &ec) != 8)
771
        return 0;
772
    start = 3600000*sh + 60000*sm + 1000*ss + 10*sc;
773
    end   = 3600000*eh + 60000*em + 1000*es + 10*ec;
774
    return end - start;
775
}
776

    
777
static int mkv_write_ass_blocks(AVFormatContext *s, ByteIOContext *pb, AVPacket *pkt)
778
{
779
    MatroskaMuxContext *mkv = s->priv_data;
780
    int i, layer = 0, max_duration = 0, size, line_size, data_size = pkt->size;
781
    uint8_t *start, *end, *data = pkt->data;
782
    ebml_master blockgroup;
783
    char buffer[2048];
784

    
785
    while (data_size) {
786
        int duration = ass_get_duration(data);
787
        max_duration = FFMAX(duration, max_duration);
788
        end = memchr(data, '\n', data_size);
789
        size = line_size = end ? end-data+1 : data_size;
790
        size -= end ? (end[-1]=='\r')+1 : 0;
791
        start = data;
792
        for (i=0; i<3; i++, start++)
793
            if (!(start = memchr(start, ',', size-(start-data))))
794
                return max_duration;
795
        size -= start - data;
796
        sscanf(data, "Dialogue: %d,", &layer);
797
        i = snprintf(buffer, sizeof(buffer), "%"PRId64",%d,",
798
                     s->streams[pkt->stream_index]->nb_frames++, layer);
799
        size = FFMIN(i+size, sizeof(buffer));
800
        memcpy(buffer+i, start, size-i);
801

    
802
        av_log(s, AV_LOG_DEBUG, "Writing block at offset %" PRIu64 ", size %d, "
803
               "pts %" PRId64 ", duration %d\n",
804
               url_ftell(pb), size, pkt->pts, duration);
805
        blockgroup = start_ebml_master(pb, MATROSKA_ID_BLOCKGROUP, mkv_blockgroup_size(size));
806
        put_ebml_id(pb, MATROSKA_ID_BLOCK);
807
        put_ebml_num(pb, size+4, 0);
808
        put_byte(pb, 0x80 | (pkt->stream_index + 1));     // this assumes stream_index is less than 126
809
        put_be16(pb, pkt->pts - mkv->cluster_pts);
810
        put_byte(pb, 0);
811
        put_buffer(pb, buffer, size);
812
        put_ebml_uint(pb, MATROSKA_ID_BLOCKDURATION, duration);
813
        end_ebml_master(pb, blockgroup);
814

    
815
        data += line_size;
816
        data_size -= line_size;
817
    }
818

    
819
    return max_duration;
820
}
821

    
822
static void mkv_write_block(AVFormatContext *s, ByteIOContext *pb,
823
                            unsigned int blockid, AVPacket *pkt, int flags)
824
{
825
    MatroskaMuxContext *mkv = s->priv_data;
826
    AVCodecContext *codec = s->streams[pkt->stream_index]->codec;
827
    uint8_t *data = NULL;
828
    int size = pkt->size;
829
    int64_t ts = mkv->tracks[pkt->stream_index].write_dts ? pkt->dts : pkt->pts;
830

    
831
    av_log(s, AV_LOG_DEBUG, "Writing block at offset %" PRIu64 ", size %d, "
832
           "pts %" PRId64 ", dts %" PRId64 ", duration %d, flags %d\n",
833
           url_ftell(pb), pkt->size, pkt->pts, pkt->dts, pkt->duration, flags);
834
    if (codec->codec_id == CODEC_ID_H264 && codec->extradata_size > 0 &&
835
        (AV_RB24(codec->extradata) == 1 || AV_RB32(codec->extradata) == 1))
836
        ff_avc_parse_nal_units_buf(pkt->data, &data, &size);
837
    else
838
        data = pkt->data;
839
    put_ebml_id(pb, blockid);
840
    put_ebml_num(pb, size+4, 0);
841
    put_byte(pb, 0x80 | (pkt->stream_index + 1));     // this assumes stream_index is less than 126
842
    put_be16(pb, ts - mkv->cluster_pts);
843
    put_byte(pb, flags);
844
    put_buffer(pb, data, size);
845
    if (data != pkt->data)
846
        av_free(data);
847
}
848

    
849
static void mkv_flush_dynbuf(AVFormatContext *s)
850
{
851
    MatroskaMuxContext *mkv = s->priv_data;
852
    int bufsize;
853
    uint8_t *dyn_buf;
854

    
855
    if (!mkv->dyn_bc)
856
        return;
857

    
858
    bufsize = url_close_dyn_buf(mkv->dyn_bc, &dyn_buf);
859
    put_buffer(s->pb, dyn_buf, bufsize);
860
    av_free(dyn_buf);
861
    mkv->dyn_bc = NULL;
862
}
863

    
864
static int mkv_write_packet(AVFormatContext *s, AVPacket *pkt)
865
{
866
    MatroskaMuxContext *mkv = s->priv_data;
867
    ByteIOContext *pb = s->pb;
868
    AVCodecContext *codec = s->streams[pkt->stream_index]->codec;
869
    int keyframe = !!(pkt->flags & PKT_FLAG_KEY);
870
    int duration = pkt->duration;
871
    int ret;
872
    int64_t ts = mkv->tracks[pkt->stream_index].write_dts ? pkt->dts : pkt->pts;
873

    
874
    if (ts == AV_NOPTS_VALUE) {
875
        av_log(s, AV_LOG_ERROR, "Can't write packet with unknown timestamp\n");
876
        return AVERROR(EINVAL);
877
    }
878

    
879
    if (url_is_streamed(s->pb)) {
880
        if (!mkv->dyn_bc)
881
            url_open_dyn_buf(&mkv->dyn_bc);
882
        pb = mkv->dyn_bc;
883
    }
884

    
885
    if (!mkv->cluster_pos) {
886
        ret = mkv_add_seekhead_entry(mkv->cluster_seekhead, MATROSKA_ID_CLUSTER, url_ftell(pb));
887
        if (ret < 0) return ret;
888

    
889
        mkv->cluster_pos = url_ftell(s->pb);
890
        mkv->cluster = start_ebml_master(pb, MATROSKA_ID_CLUSTER, 0);
891
        put_ebml_uint(pb, MATROSKA_ID_CLUSTERTIMECODE, FFMAX(0, ts));
892
        mkv->cluster_pts = FFMAX(0, ts);
893
        av_md5_update(mkv->md5_ctx, pkt->data, FFMIN(200, pkt->size));
894
    }
895

    
896
    if (codec->codec_type != AVMEDIA_TYPE_SUBTITLE) {
897
        mkv_write_block(s, pb, MATROSKA_ID_SIMPLEBLOCK, pkt, keyframe << 7);
898
    } else if (codec->codec_id == CODEC_ID_SSA) {
899
        duration = mkv_write_ass_blocks(s, pb, pkt);
900
    } else {
901
        ebml_master blockgroup = start_ebml_master(pb, MATROSKA_ID_BLOCKGROUP, mkv_blockgroup_size(pkt->size));
902
        duration = pkt->convergence_duration;
903
        mkv_write_block(s, pb, MATROSKA_ID_BLOCK, pkt, 0);
904
        put_ebml_uint(pb, MATROSKA_ID_BLOCKDURATION, duration);
905
        end_ebml_master(pb, blockgroup);
906
    }
907

    
908
    if (codec->codec_type == AVMEDIA_TYPE_VIDEO && keyframe) {
909
        ret = mkv_add_cuepoint(mkv->cues, pkt->stream_index, ts, mkv->cluster_pos);
910
        if (ret < 0) return ret;
911
    }
912

    
913
    // start a new cluster every 5 MB or 5 sec, or 32k / 1 sec for streaming
914
    if ((url_is_streamed(s->pb) && (url_ftell(pb) > 32*1024 || ts > mkv->cluster_pts + 1000))
915
        ||  url_ftell(pb) > mkv->cluster_pos + 5*1024*1024 || ts > mkv->cluster_pts + 5000) {
916
        av_log(s, AV_LOG_DEBUG, "Starting new cluster at offset %" PRIu64
917
               " bytes, pts %" PRIu64 "\n", url_ftell(pb), ts);
918
        end_ebml_master(pb, mkv->cluster);
919
        mkv->cluster_pos = 0;
920
        if (mkv->dyn_bc)
921
            mkv_flush_dynbuf(s);
922
    }
923

    
924
    mkv->duration = FFMAX(mkv->duration, ts + duration);
925
    return 0;
926
}
927

    
928
static int mkv_write_trailer(AVFormatContext *s)
929
{
930
    MatroskaMuxContext *mkv = s->priv_data;
931
    ByteIOContext *pb = s->pb;
932
    int64_t currentpos, second_seekhead, cuespos;
933
    int ret;
934

    
935
    if (mkv->dyn_bc) {
936
        end_ebml_master(mkv->dyn_bc, mkv->cluster);
937
        mkv_flush_dynbuf(s);
938
    } else if (mkv->cluster_pos) {
939
        end_ebml_master(pb, mkv->cluster);
940
    }
941

    
942
    if (!url_is_streamed(pb)) {
943
        cuespos = mkv_write_cues(pb, mkv->cues, s->nb_streams);
944
        second_seekhead = mkv_write_seekhead(pb, mkv->cluster_seekhead);
945

    
946
        ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_CUES    , cuespos);
947
        if (ret < 0) return ret;
948
        if (second_seekhead >= 0) {
949
            ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_SEEKHEAD, second_seekhead);
950
            if (ret < 0) return ret;
951
        }
952
        mkv_write_seekhead(pb, mkv->main_seekhead);
953

    
954
        // update the duration
955
        av_log(s, AV_LOG_DEBUG, "end duration = %" PRIu64 "\n", mkv->duration);
956
        currentpos = url_ftell(pb);
957
        url_fseek(pb, mkv->duration_offset, SEEK_SET);
958
        put_ebml_float(pb, MATROSKA_ID_DURATION, mkv->duration);
959

    
960
        // write the md5sum of some frames as the segment UID
961
        if (!(s->streams[0]->codec->flags & CODEC_FLAG_BITEXACT)) {
962
            uint8_t segment_uid[16];
963
            av_md5_final(mkv->md5_ctx, segment_uid);
964
            url_fseek(pb, mkv->segment_uid, SEEK_SET);
965
            put_ebml_binary(pb, MATROSKA_ID_SEGMENTUID, segment_uid, 16);
966
        }
967
        url_fseek(pb, currentpos, SEEK_SET);
968
    }
969

    
970
    end_ebml_master(pb, mkv->segment);
971
    av_free(mkv->md5_ctx);
972
    av_free(mkv->tracks);
973
    put_flush_packet(pb);
974
    return 0;
975
}
976

    
977
AVOutputFormat matroska_muxer = {
978
    "matroska",
979
    NULL_IF_CONFIG_SMALL("Matroska file format"),
980
    "video/x-matroska",
981
    "mkv",
982
    sizeof(MatroskaMuxContext),
983
    CODEC_ID_MP2,
984
    CODEC_ID_MPEG4,
985
    mkv_write_header,
986
    mkv_write_packet,
987
    mkv_write_trailer,
988
    .flags = AVFMT_GLOBALHEADER | AVFMT_VARIABLE_FPS,
989
    .codec_tag = (const AVCodecTag* const []){ff_codec_bmp_tags, ff_codec_wav_tags, 0},
990
    .subtitle_codec = CODEC_ID_TEXT,
991
};
992

    
993
AVOutputFormat matroska_audio_muxer = {
994
    "matroska",
995
    NULL_IF_CONFIG_SMALL("Matroska file format"),
996
    "audio/x-matroska",
997
    "mka",
998
    sizeof(MatroskaMuxContext),
999
    CODEC_ID_MP2,
1000
    CODEC_ID_NONE,
1001
    mkv_write_header,
1002
    mkv_write_packet,
1003
    mkv_write_trailer,
1004
    .flags = AVFMT_GLOBALHEADER,
1005
    .codec_tag = (const AVCodecTag* const []){ff_codec_wav_tags, 0},
1006
};