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ffmpeg / libavformat / matroskaenc.c @ 654b65d0

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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 {
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    unsigned int    elementid;
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    uint64_t        segmentpos;
41
} mkv_seekhead_entry;
42

    
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 {
59
    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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    uint64_t        cluster_pts;
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    int64_t         duration_offset;
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    uint64_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
88
 * 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)
105
{
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
145
    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);
169
}
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);
211
    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
    entries[cues->num_entries  ].pts = ts;
359
    entries[cues->num_entries  ].tracknum = stream + 1;
360
    entries[cues->num_entries++].cluster_pos = cluster_pos - cues->segment_offset;
361

    
362
    cues->entries = entries;
363
    return 0;
364
}
365

    
366
static int64_t mkv_write_cues(ByteIOContext *pb, mkv_cues *cues, int num_tracks)
367
{
368
    ebml_master cues_element;
369
    int64_t currentpos;
370
    int i, j;
371

    
372
    currentpos = url_ftell(pb);
373
    cues_element = start_ebml_master(pb, MATROSKA_ID_CUES, 0);
374

    
375
    for (i = 0; i < cues->num_entries; i++) {
376
        ebml_master cuepoint, track_positions;
377
        mkv_cuepoint *entry = &cues->entries[i];
378
        uint64_t pts = entry->pts;
379

    
380
        cuepoint = start_ebml_master(pb, MATROSKA_ID_POINTENTRY, MAX_CUEPOINT_SIZE(num_tracks));
381
        put_ebml_uint(pb, MATROSKA_ID_CUETIME, pts);
382

    
383
        // put all the entries from different tracks that have the exact same
384
        // timestamp into the same CuePoint
385
        for (j = 0; j < cues->num_entries - i && entry[j].pts == pts; j++) {
386
            track_positions = start_ebml_master(pb, MATROSKA_ID_CUETRACKPOSITION, MAX_CUETRACKPOS_SIZE);
387
            put_ebml_uint(pb, MATROSKA_ID_CUETRACK          , entry[j].tracknum   );
388
            put_ebml_uint(pb, MATROSKA_ID_CUECLUSTERPOSITION, entry[j].cluster_pos);
389
            end_ebml_master(pb, track_positions);
390
        }
391
        i += j - 1;
392
        end_ebml_master(pb, cuepoint);
393
    }
394
    end_ebml_master(pb, cues_element);
395

    
396
    av_free(cues->entries);
397
    av_free(cues);
398
    return currentpos;
399
}
400

    
401
static int put_xiph_codecpriv(AVFormatContext *s, ByteIOContext *pb, AVCodecContext *codec)
402
{
403
    uint8_t *header_start[3];
404
    int header_len[3];
405
    int first_header_size;
406
    int j;
407

    
408
    if (codec->codec_id == CODEC_ID_VORBIS)
409
        first_header_size = 30;
410
    else
411
        first_header_size = 42;
412

    
413
    if (ff_split_xiph_headers(codec->extradata, codec->extradata_size,
414
                              first_header_size, header_start, header_len) < 0) {
415
        av_log(s, AV_LOG_ERROR, "Extradata corrupt.\n");
416
        return -1;
417
    }
418

    
419
    put_byte(pb, 2);                    // number packets - 1
420
    for (j = 0; j < 2; j++) {
421
        put_xiph_size(pb, header_len[j]);
422
    }
423
    for (j = 0; j < 3; j++)
424
        put_buffer(pb, header_start[j], header_len[j]);
425

    
426
    return 0;
427
}
428

    
429
static void get_aac_sample_rates(AVFormatContext *s, AVCodecContext *codec, int *sample_rate, int *output_sample_rate)
430
{
431
    int sri;
432

    
433
    if (codec->extradata_size < 2) {
434
        av_log(s, AV_LOG_WARNING, "No AAC extradata, unable to determine samplerate.\n");
435
        return;
436
    }
437

    
438
    sri = ((codec->extradata[0] << 1) & 0xE) | (codec->extradata[1] >> 7);
439
    if (sri > 12) {
440
        av_log(s, AV_LOG_WARNING, "AAC samplerate index out of bounds\n");
441
        return;
442
    }
443
    *sample_rate = ff_mpeg4audio_sample_rates[sri];
444

    
445
    // if sbr, get output sample rate as well
446
    if (codec->extradata_size == 5) {
447
        sri = (codec->extradata[4] >> 3) & 0xF;
448
        if (sri > 12) {
449
            av_log(s, AV_LOG_WARNING, "AAC output samplerate index out of bounds\n");
450
            return;
451
        }
452
        *output_sample_rate = ff_mpeg4audio_sample_rates[sri];
453
    }
454
}
455

    
456
static int mkv_write_codecprivate(AVFormatContext *s, ByteIOContext *pb, AVCodecContext *codec, int native_id, int qt_id)
457
{
458
    ByteIOContext *dyn_cp;
459
    uint8_t *codecpriv;
460
    int ret, codecpriv_size;
461

    
462
    ret = url_open_dyn_buf(&dyn_cp);
463
    if(ret < 0)
464
        return ret;
465

    
466
    if (native_id) {
467
        if (codec->codec_id == CODEC_ID_VORBIS || codec->codec_id == CODEC_ID_THEORA)
468
            ret = put_xiph_codecpriv(s, dyn_cp, codec);
469
        else if (codec->codec_id == CODEC_ID_FLAC)
470
            ret = ff_flac_write_header(dyn_cp, codec);
471
        else if (codec->codec_id == CODEC_ID_H264)
472
            ret = ff_isom_write_avcc(dyn_cp, codec->extradata, codec->extradata_size);
473
        else if (codec->extradata_size)
474
            put_buffer(dyn_cp, codec->extradata, codec->extradata_size);
475
    } else if (codec->codec_type == CODEC_TYPE_VIDEO) {
476
        if (qt_id) {
477
            if (!codec->codec_tag)
478
                codec->codec_tag = ff_codec_get_tag(codec_movvideo_tags, codec->codec_id);
479
            if (codec->extradata_size)
480
                put_buffer(dyn_cp, codec->extradata, codec->extradata_size);
481
        } else {
482
            if (!codec->codec_tag)
483
                codec->codec_tag = ff_codec_get_tag(ff_codec_bmp_tags, codec->codec_id);
484
            if (!codec->codec_tag) {
485
                av_log(s, AV_LOG_ERROR, "No bmp codec ID found.");
486
                ret = -1;
487
            }
488

    
489
            ff_put_bmp_header(dyn_cp, codec, ff_codec_bmp_tags, 0);
490
        }
491

    
492
    } else if (codec->codec_type == CODEC_TYPE_AUDIO) {
493
        if (!codec->codec_tag)
494
            codec->codec_tag = ff_codec_get_tag(ff_codec_wav_tags, codec->codec_id);
495
        if (!codec->codec_tag) {
496
            av_log(s, AV_LOG_ERROR, "No wav codec ID found.");
497
            ret = -1;
498
        }
499

    
500
        ff_put_wav_header(dyn_cp, codec);
501
    }
502

    
503
    codecpriv_size = url_close_dyn_buf(dyn_cp, &codecpriv);
504
    if (codecpriv_size)
505
        put_ebml_binary(pb, MATROSKA_ID_CODECPRIVATE, codecpriv, codecpriv_size);
506
    av_free(codecpriv);
507
    return ret;
508
}
509

    
510
static int mkv_write_tracks(AVFormatContext *s)
511
{
512
    MatroskaMuxContext *mkv = s->priv_data;
513
    ByteIOContext *pb = s->pb;
514
    ebml_master tracks;
515
    int i, j, ret;
516

    
517
    ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_TRACKS, url_ftell(pb));
518
    if (ret < 0) return ret;
519

    
520
    tracks = start_ebml_master(pb, MATROSKA_ID_TRACKS, 0);
521
    for (i = 0; i < s->nb_streams; i++) {
522
        AVStream *st = s->streams[i];
523
        AVCodecContext *codec = st->codec;
524
        ebml_master subinfo, track;
525
        int native_id = 0;
526
        int qt_id = 0;
527
        int bit_depth = av_get_bits_per_sample(codec->codec_id);
528
        int sample_rate = codec->sample_rate;
529
        int output_sample_rate = 0;
530
        AVMetadataTag *tag;
531

    
532
        if (!bit_depth)
533
            bit_depth = av_get_bits_per_sample_format(codec->sample_fmt);
534

    
535
        if (codec->codec_id == CODEC_ID_AAC)
536
            get_aac_sample_rates(s, codec, &sample_rate, &output_sample_rate);
537

    
538
        track = start_ebml_master(pb, MATROSKA_ID_TRACKENTRY, 0);
539
        put_ebml_uint (pb, MATROSKA_ID_TRACKNUMBER     , i + 1);
540
        put_ebml_uint (pb, MATROSKA_ID_TRACKUID        , i + 1);
541
        put_ebml_uint (pb, MATROSKA_ID_TRACKFLAGLACING , 0);    // no lacing (yet)
542
        put_ebml_float(pb, MATROSKA_ID_TRACKTIMECODESCALE, 1.0);
543

    
544
        if ((tag = av_metadata_get(st->metadata, "title", NULL, 0)))
545
            put_ebml_string(pb, MATROSKA_ID_TRACKNAME, tag->value);
546
        tag = av_metadata_get(st->metadata, "language", NULL, 0);
547
        put_ebml_string(pb, MATROSKA_ID_TRACKLANGUAGE, tag ? tag->value:"und");
548

    
549
        if (st->disposition)
550
            put_ebml_uint(pb, MATROSKA_ID_TRACKFLAGDEFAULT, !!(st->disposition & AV_DISPOSITION_DEFAULT));
551

    
552
        // look for a codec ID string specific to mkv to use,
553
        // if none are found, use AVI codes
554
        for (j = 0; ff_mkv_codec_tags[j].id != CODEC_ID_NONE; j++) {
555
            if (ff_mkv_codec_tags[j].id == codec->codec_id) {
556
                put_ebml_string(pb, MATROSKA_ID_CODECID, ff_mkv_codec_tags[j].str);
557
                native_id = 1;
558
                break;
559
            }
560
        }
561

    
562
        switch (codec->codec_type) {
563
            case CODEC_TYPE_VIDEO:
564
                put_ebml_uint(pb, MATROSKA_ID_TRACKTYPE, MATROSKA_TRACK_TYPE_VIDEO);
565

    
566
                if (!native_id &&
567
                      ff_codec_get_tag(codec_movvideo_tags, codec->codec_id) &&
568
                    (!ff_codec_get_tag(ff_codec_bmp_tags,   codec->codec_id)
569
                     || codec->codec_id == CODEC_ID_SVQ1
570
                     || codec->codec_id == CODEC_ID_SVQ3
571
                     || codec->codec_id == CODEC_ID_CINEPAK))
572
                    qt_id = 1;
573

    
574
                if (qt_id)
575
                    put_ebml_string(pb, MATROSKA_ID_CODECID, "V_QUICKTIME");
576
                else if (!native_id) {
577
                    // if there is no mkv-specific codec ID, use VFW mode
578
                    put_ebml_string(pb, MATROSKA_ID_CODECID, "V_MS/VFW/FOURCC");
579
                    mkv->tracks[i].write_dts = 1;
580
                }
581

    
582
                subinfo = start_ebml_master(pb, MATROSKA_ID_TRACKVIDEO, 0);
583
                // XXX: interlace flag?
584
                put_ebml_uint (pb, MATROSKA_ID_VIDEOPIXELWIDTH , codec->width);
585
                put_ebml_uint (pb, MATROSKA_ID_VIDEOPIXELHEIGHT, codec->height);
586
                if (st->sample_aspect_ratio.num) {
587
                    int d_width = codec->width*av_q2d(st->sample_aspect_ratio);
588
                    put_ebml_uint(pb, MATROSKA_ID_VIDEODISPLAYWIDTH , d_width);
589
                    put_ebml_uint(pb, MATROSKA_ID_VIDEODISPLAYHEIGHT, codec->height);
590
                }
591
                end_ebml_master(pb, subinfo);
592
                break;
593

    
594
            case CODEC_TYPE_AUDIO:
595
                put_ebml_uint(pb, MATROSKA_ID_TRACKTYPE, MATROSKA_TRACK_TYPE_AUDIO);
596

    
597
                if (!native_id)
598
                    // no mkv-specific ID, use ACM mode
599
                    put_ebml_string(pb, MATROSKA_ID_CODECID, "A_MS/ACM");
600

    
601
                subinfo = start_ebml_master(pb, MATROSKA_ID_TRACKAUDIO, 0);
602
                put_ebml_uint  (pb, MATROSKA_ID_AUDIOCHANNELS    , codec->channels);
603
                put_ebml_float (pb, MATROSKA_ID_AUDIOSAMPLINGFREQ, sample_rate);
604
                if (output_sample_rate)
605
                    put_ebml_float(pb, MATROSKA_ID_AUDIOOUTSAMPLINGFREQ, output_sample_rate);
606
                if (bit_depth)
607
                    put_ebml_uint(pb, MATROSKA_ID_AUDIOBITDEPTH, bit_depth);
608
                end_ebml_master(pb, subinfo);
609
                break;
610

    
611
            case CODEC_TYPE_SUBTITLE:
612
                put_ebml_uint(pb, MATROSKA_ID_TRACKTYPE, MATROSKA_TRACK_TYPE_SUBTITLE);
613
                break;
614
            default:
615
                av_log(s, AV_LOG_ERROR, "Only audio, video, and subtitles are supported for Matroska.");
616
                break;
617
        }
618
        ret = mkv_write_codecprivate(s, pb, codec, native_id, qt_id);
619
        if (ret < 0) return ret;
620

    
621
        end_ebml_master(pb, track);
622

    
623
        // ms precision is the de-facto standard timescale for mkv files
624
        av_set_pts_info(st, 64, 1, 1000);
625
    }
626
    end_ebml_master(pb, tracks);
627
    return 0;
628
}
629

    
630
static int mkv_write_chapters(AVFormatContext *s)
631
{
632
    MatroskaMuxContext *mkv = s->priv_data;
633
    ByteIOContext *pb = s->pb;
634
    ebml_master chapters, editionentry;
635
    AVRational scale = {1, 1E9};
636
    int i, ret;
637

    
638
    if (!s->nb_chapters)
639
        return 0;
640

    
641
    ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_CHAPTERS, url_ftell(pb));
642
    if (ret < 0) return ret;
643

    
644
    chapters     = start_ebml_master(pb, MATROSKA_ID_CHAPTERS    , 0);
645
    editionentry = start_ebml_master(pb, MATROSKA_ID_EDITIONENTRY, 0);
646
    put_ebml_uint(pb, MATROSKA_ID_EDITIONFLAGDEFAULT, 1);
647
    put_ebml_uint(pb, MATROSKA_ID_EDITIONFLAGHIDDEN , 0);
648
    for (i = 0; i < s->nb_chapters; i++) {
649
        ebml_master chapteratom, chapterdisplay;
650
        AVChapter *c     = s->chapters[i];
651
        AVMetadataTag *t = NULL;
652

    
653
        chapteratom = start_ebml_master(pb, MATROSKA_ID_CHAPTERATOM, 0);
654
        put_ebml_uint(pb, MATROSKA_ID_CHAPTERUID, c->id);
655
        put_ebml_uint(pb, MATROSKA_ID_CHAPTERTIMESTART,
656
                      av_rescale_q(c->start, c->time_base, scale));
657
        put_ebml_uint(pb, MATROSKA_ID_CHAPTERTIMEEND,
658
                      av_rescale_q(c->end,   c->time_base, scale));
659
        put_ebml_uint(pb, MATROSKA_ID_CHAPTERFLAGHIDDEN , 0);
660
        put_ebml_uint(pb, MATROSKA_ID_CHAPTERFLAGENABLED, 1);
661
        if ((t = av_metadata_get(c->metadata, "title", NULL, 0))) {
662
            chapterdisplay = start_ebml_master(pb, MATROSKA_ID_CHAPTERDISPLAY, 0);
663
            put_ebml_string(pb, MATROSKA_ID_CHAPSTRING, t->value);
664
            put_ebml_string(pb, MATROSKA_ID_CHAPLANG  , "und");
665
            end_ebml_master(pb, chapterdisplay);
666
        }
667
        end_ebml_master(pb, chapteratom);
668
    }
669
    end_ebml_master(pb, editionentry);
670
    end_ebml_master(pb, chapters);
671
    return 0;
672
}
673

    
674
static int mkv_write_header(AVFormatContext *s)
675
{
676
    MatroskaMuxContext *mkv = s->priv_data;
677
    ByteIOContext *pb = s->pb;
678
    ebml_master ebml_header, segment_info;
679
    AVMetadataTag *tag;
680
    int ret;
681

    
682
    mkv->md5_ctx = av_mallocz(av_md5_size);
683
    av_md5_init(mkv->md5_ctx);
684
    mkv->tracks = av_mallocz(s->nb_streams * sizeof(*mkv->tracks));
685

    
686
    ebml_header = start_ebml_master(pb, EBML_ID_HEADER, 0);
687
    put_ebml_uint   (pb, EBML_ID_EBMLVERSION        ,           1);
688
    put_ebml_uint   (pb, EBML_ID_EBMLREADVERSION    ,           1);
689
    put_ebml_uint   (pb, EBML_ID_EBMLMAXIDLENGTH    ,           4);
690
    put_ebml_uint   (pb, EBML_ID_EBMLMAXSIZELENGTH  ,           8);
691
    put_ebml_string (pb, EBML_ID_DOCTYPE            ,  "matroska");
692
    put_ebml_uint   (pb, EBML_ID_DOCTYPEVERSION     ,           2);
693
    put_ebml_uint   (pb, EBML_ID_DOCTYPEREADVERSION ,           2);
694
    end_ebml_master(pb, ebml_header);
695

    
696
    mkv->segment = start_ebml_master(pb, MATROSKA_ID_SEGMENT, 0);
697
    mkv->segment_offset = url_ftell(pb);
698

    
699
    // we write 2 seek heads - one at the end of the file to point to each
700
    // cluster, and one at the beginning to point to all other level one
701
    // elements (including the seek head at the end of the file), which
702
    // isn't more than 10 elements if we only write one of each other
703
    // currently defined level 1 element
704
    mkv->main_seekhead    = mkv_start_seekhead(pb, mkv->segment_offset, 10);
705
    mkv->cluster_seekhead = mkv_start_seekhead(pb, mkv->segment_offset, 0);
706
    if (mkv->main_seekhead == NULL || mkv->cluster_seekhead == NULL)
707
        return AVERROR(ENOMEM);
708

    
709
    ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_INFO, url_ftell(pb));
710
    if (ret < 0) return ret;
711

    
712
    segment_info = start_ebml_master(pb, MATROSKA_ID_INFO, 0);
713
    put_ebml_uint(pb, MATROSKA_ID_TIMECODESCALE, 1000000);
714
    if ((tag = av_metadata_get(s->metadata, "title", NULL, 0)))
715
        put_ebml_string(pb, MATROSKA_ID_TITLE, tag->value);
716
    if (!(s->streams[0]->codec->flags & CODEC_FLAG_BITEXACT)) {
717
        put_ebml_string(pb, MATROSKA_ID_MUXINGAPP , LIBAVFORMAT_IDENT);
718
        put_ebml_string(pb, MATROSKA_ID_WRITINGAPP, LIBAVFORMAT_IDENT);
719

    
720
        // reserve space to write the segment UID later
721
        mkv->segment_uid = url_ftell(pb);
722
        put_ebml_void(pb, 19);
723
    }
724

    
725
    // reserve space for the duration
726
    mkv->duration = 0;
727
    mkv->duration_offset = url_ftell(pb);
728
    put_ebml_void(pb, 11);                  // assumes double-precision float to be written
729
    end_ebml_master(pb, segment_info);
730

    
731
    ret = mkv_write_tracks(s);
732
    if (ret < 0) return ret;
733

    
734
    ret = mkv_write_chapters(s);
735
    if (ret < 0) return ret;
736

    
737
    if (url_is_streamed(s->pb))
738
        mkv_write_seekhead(pb, mkv->main_seekhead);
739

    
740
    mkv->cues = mkv_start_cues(mkv->segment_offset);
741
    if (mkv->cues == NULL)
742
        return AVERROR(ENOMEM);
743

    
744
    put_flush_packet(pb);
745
    return 0;
746
}
747

    
748
static int mkv_blockgroup_size(int pkt_size)
749
{
750
    int size = pkt_size + 4;
751
    size += ebml_num_size(size);
752
    size += 2;              // EBML ID for block and block duration
753
    size += 8;              // max size of block duration
754
    size += ebml_num_size(size);
755
    size += 1;              // blockgroup EBML ID
756
    return size;
757
}
758

    
759
static int ass_get_duration(const uint8_t *p)
760
{
761
    int sh, sm, ss, sc, eh, em, es, ec;
762
    uint64_t start, end;
763

    
764
    if (sscanf(p, "%*[^,],%d:%d:%d%*c%d,%d:%d:%d%*c%d",
765
               &sh, &sm, &ss, &sc, &eh, &em, &es, &ec) != 8)
766
        return 0;
767
    start = 3600000*sh + 60000*sm + 1000*ss + 10*sc;
768
    end   = 3600000*eh + 60000*em + 1000*es + 10*ec;
769
    return end - start;
770
}
771

    
772
static int mkv_write_ass_blocks(AVFormatContext *s, ByteIOContext *pb, AVPacket *pkt)
773
{
774
    MatroskaMuxContext *mkv = s->priv_data;
775
    int i, layer = 0, max_duration = 0, size, line_size, data_size = pkt->size;
776
    uint8_t *start, *end, *data = pkt->data;
777
    ebml_master blockgroup;
778
    char buffer[2048];
779

    
780
    while (data_size) {
781
        int duration = ass_get_duration(data);
782
        max_duration = FFMAX(duration, max_duration);
783
        end = memchr(data, '\n', data_size);
784
        size = line_size = end ? end-data+1 : data_size;
785
        size -= end ? (end[-1]=='\r')+1 : 0;
786
        start = data;
787
        for (i=0; i<3; i++, start++)
788
            if (!(start = memchr(start, ',', size-(start-data))))
789
                return max_duration;
790
        size -= start - data;
791
        sscanf(data, "Dialogue: %d,", &layer);
792
        i = snprintf(buffer, sizeof(buffer), "%"PRId64",%d,",
793
                     s->streams[pkt->stream_index]->nb_frames++, layer);
794
        size = FFMIN(i+size, sizeof(buffer));
795
        memcpy(buffer+i, start, size-i);
796

    
797
        av_log(s, AV_LOG_DEBUG, "Writing block at offset %" PRIu64 ", size %d, "
798
               "pts %" PRId64 ", duration %d\n",
799
               url_ftell(pb), size, pkt->pts, duration);
800
        blockgroup = start_ebml_master(pb, MATROSKA_ID_BLOCKGROUP, mkv_blockgroup_size(size));
801
        put_ebml_id(pb, MATROSKA_ID_BLOCK);
802
        put_ebml_num(pb, size+4, 0);
803
        put_byte(pb, 0x80 | (pkt->stream_index + 1));     // this assumes stream_index is less than 126
804
        put_be16(pb, pkt->pts - mkv->cluster_pts);
805
        put_byte(pb, 0);
806
        put_buffer(pb, buffer, size);
807
        put_ebml_uint(pb, MATROSKA_ID_BLOCKDURATION, duration);
808
        end_ebml_master(pb, blockgroup);
809

    
810
        data += line_size;
811
        data_size -= line_size;
812
    }
813

    
814
    return max_duration;
815
}
816

    
817
static void mkv_write_block(AVFormatContext *s, ByteIOContext *pb,
818
                            unsigned int blockid, AVPacket *pkt, int flags)
819
{
820
    MatroskaMuxContext *mkv = s->priv_data;
821
    AVCodecContext *codec = s->streams[pkt->stream_index]->codec;
822
    uint8_t *data = NULL;
823
    int size = pkt->size;
824
    int64_t ts = mkv->tracks[pkt->stream_index].write_dts ? pkt->dts : pkt->pts;
825

    
826
    av_log(s, AV_LOG_DEBUG, "Writing block at offset %" PRIu64 ", size %d, "
827
           "pts %" PRId64 ", dts %" PRId64 ", duration %d, flags %d\n",
828
           url_ftell(pb), pkt->size, pkt->pts, pkt->dts, pkt->duration, flags);
829
    if (codec->codec_id == CODEC_ID_H264 && codec->extradata_size > 0 &&
830
        (AV_RB24(codec->extradata) == 1 || AV_RB32(codec->extradata) == 1))
831
        ff_avc_parse_nal_units_buf(pkt->data, &data, &size);
832
    else
833
        data = pkt->data;
834
    put_ebml_id(pb, blockid);
835
    put_ebml_num(pb, size+4, 0);
836
    put_byte(pb, 0x80 | (pkt->stream_index + 1));     // this assumes stream_index is less than 126
837
    put_be16(pb, ts - mkv->cluster_pts);
838
    put_byte(pb, flags);
839
    put_buffer(pb, data, size);
840
    if (data != pkt->data)
841
        av_free(data);
842
}
843

    
844
static void mkv_flush_dynbuf(AVFormatContext *s)
845
{
846
    MatroskaMuxContext *mkv = s->priv_data;
847
    int bufsize;
848
    uint8_t *dyn_buf;
849

    
850
    if (!mkv->dyn_bc)
851
        return;
852

    
853
    bufsize = url_close_dyn_buf(mkv->dyn_bc, &dyn_buf);
854
    put_buffer(s->pb, dyn_buf, bufsize);
855
    av_free(dyn_buf);
856
    mkv->dyn_bc = NULL;
857
}
858

    
859
static int mkv_write_packet(AVFormatContext *s, AVPacket *pkt)
860
{
861
    MatroskaMuxContext *mkv = s->priv_data;
862
    ByteIOContext *pb = s->pb;
863
    AVCodecContext *codec = s->streams[pkt->stream_index]->codec;
864
    int keyframe = !!(pkt->flags & PKT_FLAG_KEY);
865
    int duration = pkt->duration;
866
    int ret;
867
    int64_t ts = mkv->tracks[pkt->stream_index].write_dts ? pkt->dts : pkt->pts;
868

    
869
    if (ts == AV_NOPTS_VALUE) {
870
        av_log(s, AV_LOG_ERROR, "Can't write packet with unknown timestamp\n");
871
        return AVERROR(EINVAL);
872
    }
873

    
874
    if (url_is_streamed(s->pb)) {
875
        if (!mkv->dyn_bc)
876
            url_open_dyn_buf(&mkv->dyn_bc);
877
        pb = mkv->dyn_bc;
878
    }
879

    
880
    if (!mkv->cluster_pos) {
881
        ret = mkv_add_seekhead_entry(mkv->cluster_seekhead, MATROSKA_ID_CLUSTER, url_ftell(pb));
882
        if (ret < 0) return ret;
883

    
884
        mkv->cluster_pos = url_ftell(s->pb);
885
        mkv->cluster = start_ebml_master(pb, MATROSKA_ID_CLUSTER, 0);
886
        put_ebml_uint(pb, MATROSKA_ID_CLUSTERTIMECODE, ts);
887
        mkv->cluster_pts = ts;
888
        av_md5_update(mkv->md5_ctx, pkt->data, FFMIN(200, pkt->size));
889
    }
890

    
891
    if (codec->codec_type != CODEC_TYPE_SUBTITLE) {
892
        mkv_write_block(s, pb, MATROSKA_ID_SIMPLEBLOCK, pkt, keyframe << 7);
893
    } else if (codec->codec_id == CODEC_ID_SSA) {
894
        duration = mkv_write_ass_blocks(s, pb, pkt);
895
    } else {
896
        ebml_master blockgroup = start_ebml_master(pb, MATROSKA_ID_BLOCKGROUP, mkv_blockgroup_size(pkt->size));
897
        duration = pkt->convergence_duration;
898
        mkv_write_block(s, pb, MATROSKA_ID_BLOCK, pkt, 0);
899
        put_ebml_uint(pb, MATROSKA_ID_BLOCKDURATION, duration);
900
        end_ebml_master(pb, blockgroup);
901
    }
902

    
903
    if (codec->codec_type == CODEC_TYPE_VIDEO && keyframe) {
904
        ret = mkv_add_cuepoint(mkv->cues, pkt->stream_index, ts, mkv->cluster_pos);
905
        if (ret < 0) return ret;
906
    }
907

    
908
    // start a new cluster every 5 MB or 5 sec, or 32k / 1 sec for streaming
909
    if (url_is_streamed(s->pb) && (url_ftell(pb) > 32*1024 || ts > mkv->cluster_pts + 1000)
910
        ||  url_ftell(pb) > mkv->cluster_pos + 5*1024*1024 || ts > mkv->cluster_pts + 5000) {
911
        av_log(s, AV_LOG_DEBUG, "Starting new cluster at offset %" PRIu64
912
               " bytes, pts %" PRIu64 "\n", url_ftell(pb), ts);
913
        end_ebml_master(pb, mkv->cluster);
914
        mkv->cluster_pos = 0;
915
        if (mkv->dyn_bc)
916
            mkv_flush_dynbuf(s);
917
    }
918

    
919
    mkv->duration = FFMAX(mkv->duration, ts + duration);
920
    return 0;
921
}
922

    
923
static int mkv_write_trailer(AVFormatContext *s)
924
{
925
    MatroskaMuxContext *mkv = s->priv_data;
926
    ByteIOContext *pb = s->pb;
927
    int64_t currentpos, second_seekhead, cuespos;
928
    int ret;
929

    
930
    if (mkv->dyn_bc) {
931
        end_ebml_master(mkv->dyn_bc, mkv->cluster);
932
        mkv_flush_dynbuf(s);
933
    } else if (mkv->cluster_pos) {
934
        end_ebml_master(pb, mkv->cluster);
935
    }
936

    
937
    if (!url_is_streamed(pb)) {
938
        cuespos = mkv_write_cues(pb, mkv->cues, s->nb_streams);
939
        second_seekhead = mkv_write_seekhead(pb, mkv->cluster_seekhead);
940

    
941
        ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_CUES    , cuespos);
942
        if (ret < 0) return ret;
943
        if (second_seekhead >= 0) {
944
            ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_SEEKHEAD, second_seekhead);
945
            if (ret < 0) return ret;
946
        }
947
        mkv_write_seekhead(pb, mkv->main_seekhead);
948

    
949
        // update the duration
950
        av_log(s, AV_LOG_DEBUG, "end duration = %" PRIu64 "\n", mkv->duration);
951
        currentpos = url_ftell(pb);
952
        url_fseek(pb, mkv->duration_offset, SEEK_SET);
953
        put_ebml_float(pb, MATROSKA_ID_DURATION, mkv->duration);
954

    
955
        // write the md5sum of some frames as the segment UID
956
        if (!(s->streams[0]->codec->flags & CODEC_FLAG_BITEXACT)) {
957
            uint8_t segment_uid[16];
958
            av_md5_final(mkv->md5_ctx, segment_uid);
959
            url_fseek(pb, mkv->segment_uid, SEEK_SET);
960
            put_ebml_binary(pb, MATROSKA_ID_SEGMENTUID, segment_uid, 16);
961
        }
962
        url_fseek(pb, currentpos, SEEK_SET);
963
    }
964

    
965
    end_ebml_master(pb, mkv->segment);
966
    av_free(mkv->md5_ctx);
967
    av_free(mkv->tracks);
968
    put_flush_packet(pb);
969
    return 0;
970
}
971

    
972
AVOutputFormat matroska_muxer = {
973
    "matroska",
974
    NULL_IF_CONFIG_SMALL("Matroska file format"),
975
    "video/x-matroska",
976
    "mkv",
977
    sizeof(MatroskaMuxContext),
978
    CODEC_ID_MP2,
979
    CODEC_ID_MPEG4,
980
    mkv_write_header,
981
    mkv_write_packet,
982
    mkv_write_trailer,
983
    .flags = AVFMT_GLOBALHEADER | AVFMT_VARIABLE_FPS,
984
    .codec_tag = (const AVCodecTag* const []){ff_codec_bmp_tags, ff_codec_wav_tags, 0},
985
    .subtitle_codec = CODEC_ID_TEXT,
986
};
987

    
988
AVOutputFormat matroska_audio_muxer = {
989
    "matroska",
990
    NULL_IF_CONFIG_SMALL("Matroska file format"),
991
    "audio/x-matroska",
992
    "mka",
993
    sizeof(MatroskaMuxContext),
994
    CODEC_ID_MP2,
995
    CODEC_ID_NONE,
996
    mkv_write_header,
997
    mkv_write_packet,
998
    mkv_write_trailer,
999
    .flags = AVFMT_GLOBALHEADER,
1000
    .codec_tag = (const AVCodecTag* const []){ff_codec_wav_tags, 0},
1001
};