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ffmpeg / libavformat / matroskaenc.c @ ca93bc17

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1
/*
2
 * Matroska muxer
3
 * Copyright (c) 2007 David Conrad
4
 *
5
 * 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,
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.
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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 "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"
31

    
32
typedef struct ebml_master {
33
    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;
36

    
37
typedef struct mkv_seekhead_entry {
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    unsigned int    elementid;
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    uint64_t        segmentpos;
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} mkv_seekhead_entry;
41

    
42
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;
50

    
51
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
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} mkv_cuepoint;
56

    
57
typedef struct {
58
    int64_t         segment_offset;
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    mkv_cuepoint    *entries;
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    int             num_entries;
61
} mkv_cues;
62

    
63
typedef struct MatroskaMuxContext {
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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;
75

    
76
    struct AVMD5    *md5_ctx;
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} MatroskaMuxContext;
78

    
79

    
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/** 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 */
82
#define MAX_SEEKENTRY_SIZE 21
83

    
84
/** per-cuepoint-track - 3 1-byte EBML IDs, 3 1-byte EBML sizes, 2
85
 * 8-byte uint max */
86
#define MAX_CUETRACKPOS_SIZE 22
87

    
88
/** per-cuepoint - 2 1-byte EBML IDs, 2 1-byte EBML sizes, 8-byte uint max */
89
#define MAX_CUEPOINT_SIZE(num_tracks) 12 + MAX_CUETRACKPOS_SIZE*num_tracks
90

    
91

    
92
static int ebml_id_size(unsigned int id)
93
{
94
    return (av_log2(id+1)-1)/7+1;
95
}
96

    
97
static void put_ebml_id(ByteIOContext *pb, unsigned int id)
98
{
99
    int i = ebml_id_size(id);
100
    while (i--)
101
        put_byte(pb, id >> (i*8));
102
}
103

    
104
/**
105
 * Write an EBML size meaning "unknown size".
106
 *
107
 * @param bytes The number of bytes the size should occupy (maximum: 8).
108
 */
109
static void put_ebml_size_unknown(ByteIOContext *pb, int bytes)
110
{
111
    assert(bytes <= 8);
112
    put_byte(pb, 0x1ff >> bytes);
113
    while (--bytes)
114
        put_byte(pb, 0xff);
115
}
116

    
117
/**
118
 * Calculate how many bytes are needed to represent a given number in EBML.
119
 */
120
static int ebml_num_size(uint64_t num)
121
{
122
    int bytes = 1;
123
    while ((num+1) >> bytes*7) bytes++;
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    return bytes;
125
}
126

    
127
/**
128
 * Write a number in EBML variable length format.
129
 *
130
 * @param bytes The number of bytes that need to be used to write the number.
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 *              If zero, any number of bytes can be used.
132
 */
133
static void put_ebml_num(ByteIOContext *pb, uint64_t num, int bytes)
134
{
135
    int i, needed_bytes = ebml_num_size(num);
136

    
137
    // sizes larger than this are currently undefined in EBML
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    assert(num < (1ULL<<56)-1);
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140
    if (bytes == 0)
141
        // don't care how many bytes are used, so use the min
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        bytes = needed_bytes;
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    // the bytes needed to write the given size would exceed the bytes
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    // that we need to use, so write unknown size. This shouldn't happen.
145
    assert(bytes >= needed_bytes);
146

    
147
    num |= 1ULL << bytes*7;
148
    for (i = bytes - 1; i >= 0; i--)
149
        put_byte(pb, num >> i*8);
150
}
151

    
152
static void put_ebml_uint(ByteIOContext *pb, unsigned int elementid, uint64_t val)
153
{
154
    int i, bytes = 1;
155
    uint64_t tmp = val;
156
    while (tmp>>=8) bytes++;
157

    
158
    put_ebml_id(pb, elementid);
159
    put_ebml_num(pb, bytes, 0);
160
    for (i = bytes - 1; i >= 0; i--)
161
        put_byte(pb, val >> i*8);
162
}
163

    
164
static void put_ebml_float(ByteIOContext *pb, unsigned int elementid, double val)
165
{
166
    put_ebml_id(pb, elementid);
167
    put_ebml_num(pb, 8, 0);
168
    put_be64(pb, av_dbl2int(val));
169
}
170

    
171
static void put_ebml_binary(ByteIOContext *pb, unsigned int elementid,
172
                            const uint8_t *buf, int size)
173
{
174
    put_ebml_id(pb, elementid);
175
    put_ebml_num(pb, size, 0);
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    put_buffer(pb, buf, size);
177
}
178

    
179
static void put_ebml_string(ByteIOContext *pb, unsigned int elementid, const char *str)
180
{
181
    put_ebml_binary(pb, elementid, str, strlen(str));
182
}
183

    
184
/**
185
 * Writes a void element of a given size. Useful for reserving space in
186
 * the file to be written to later.
187
 *
188
 * @param size The number of bytes to reserve, which must be at least 2.
189
 */
190
static void put_ebml_void(ByteIOContext *pb, uint64_t size)
191
{
192
    int64_t currentpos = url_ftell(pb);
193

    
194
    assert(size >= 2);
195

    
196
    put_ebml_id(pb, EBML_ID_VOID);
197
    // we need to subtract the length needed to store the size from the
198
    // 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
200
    if (size < 10)
201
        put_ebml_num(pb, size-1, 0);
202
    else
203
        put_ebml_num(pb, size-9, 8);
204
    while(url_ftell(pb) < currentpos + size)
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        put_byte(pb, 0);
206
}
207

    
208
static ebml_master start_ebml_master(ByteIOContext *pb, unsigned int elementid, uint64_t expectedsize)
209
{
210
    int bytes = expectedsize ? ebml_num_size(expectedsize) : 8;
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    put_ebml_id(pb, elementid);
212
    put_ebml_size_unknown(pb, bytes);
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    return (ebml_master){ url_ftell(pb), bytes };
214
}
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static void end_ebml_master(ByteIOContext *pb, ebml_master master)
217
{
218
    int64_t pos = url_ftell(pb);
219

    
220
    // leave the unknown size for masters when streaming
221
    if (url_is_streamed(pb))
222
        return;
223

    
224
    url_fseek(pb, master.pos - master.sizebytes, SEEK_SET);
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    put_ebml_num(pb, pos - master.pos, master.sizebytes);
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    url_fseek(pb, pos, SEEK_SET);
227
}
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229
static void put_xiph_size(ByteIOContext *pb, int size)
230
{
231
    int i;
232
    for (i = 0; i < size / 255; i++)
233
        put_byte(pb, 255);
234
    put_byte(pb, size % 255);
235
}
236

    
237
/**
238
 * Initialize a mkv_seekhead element to be ready to index level 1 Matroska
239
 * elements. If a maximum number of elements is specified, enough space
240
 * will be reserved at the current file location to write a seek head of
241
 * that size.
242
 *
243
 * @param segment_offset The absolute offset to the position in the file
244
 *                       where the segment begins.
245
 * @param numelements The maximum number of elements that will be indexed
246
 *                    by this seek head, 0 if unlimited.
247
 */
248
static mkv_seekhead * mkv_start_seekhead(ByteIOContext *pb, int64_t segment_offset, int numelements)
249
{
250
    mkv_seekhead *new_seekhead = av_mallocz(sizeof(mkv_seekhead));
251
    if (new_seekhead == NULL)
252
        return NULL;
253

    
254
    new_seekhead->segment_offset = segment_offset;
255

    
256
    if (numelements > 0) {
257
        new_seekhead->filepos = url_ftell(pb);
258
        // 21 bytes max for a seek entry, 10 bytes max for the SeekHead ID
259
        // and size, and 3 bytes to guarantee that an EBML void element
260
        // will fit afterwards
261
        new_seekhead->reserved_size = numelements * MAX_SEEKENTRY_SIZE + 13;
262
        new_seekhead->max_entries = numelements;
263
        put_ebml_void(pb, new_seekhead->reserved_size);
264
    }
265
    return new_seekhead;
266
}
267

    
268
static int mkv_add_seekhead_entry(mkv_seekhead *seekhead, unsigned int elementid, uint64_t filepos)
269
{
270
    mkv_seekhead_entry *entries = seekhead->entries;
271

    
272
    // don't store more elements than we reserved space for
273
    if (seekhead->max_entries > 0 && seekhead->max_entries <= seekhead->num_entries)
274
        return -1;
275

    
276
    entries = av_realloc(entries, (seekhead->num_entries + 1) * sizeof(mkv_seekhead_entry));
277
    if (entries == NULL)
278
        return AVERROR(ENOMEM);
279

    
280
    entries[seekhead->num_entries  ].elementid = elementid;
281
    entries[seekhead->num_entries++].segmentpos = filepos - seekhead->segment_offset;
282

    
283
    seekhead->entries = entries;
284
    return 0;
285
}
286

    
287
/**
288
 * Write the seek head to the file and free it. If a maximum number of
289
 * elements was specified to mkv_start_seekhead(), the seek head will
290
 * be written at the location reserved for it. Otherwise, it is written
291
 * at the current location in the file.
292
 *
293
 * @return The file offset where the seekhead was written.
294
 */
295
static int64_t mkv_write_seekhead(ByteIOContext *pb, mkv_seekhead *seekhead)
296
{
297
    ebml_master metaseek, seekentry;
298
    int64_t currentpos;
299
    int i;
300

    
301
    currentpos = url_ftell(pb);
302

    
303
    if (seekhead->reserved_size > 0)
304
        url_fseek(pb, seekhead->filepos, SEEK_SET);
305

    
306
    metaseek = start_ebml_master(pb, MATROSKA_ID_SEEKHEAD, seekhead->reserved_size);
307
    for (i = 0; i < seekhead->num_entries; i++) {
308
        mkv_seekhead_entry *entry = &seekhead->entries[i];
309

    
310
        seekentry = start_ebml_master(pb, MATROSKA_ID_SEEKENTRY, MAX_SEEKENTRY_SIZE);
311

    
312
        put_ebml_id(pb, MATROSKA_ID_SEEKID);
313
        put_ebml_num(pb, ebml_id_size(entry->elementid), 0);
314
        put_ebml_id(pb, entry->elementid);
315

    
316
        put_ebml_uint(pb, MATROSKA_ID_SEEKPOSITION, entry->segmentpos);
317
        end_ebml_master(pb, seekentry);
318
    }
319
    end_ebml_master(pb, metaseek);
320

    
321
    if (seekhead->reserved_size > 0) {
322
        uint64_t remaining = seekhead->filepos + seekhead->reserved_size - url_ftell(pb);
323
        put_ebml_void(pb, remaining);
324
        url_fseek(pb, currentpos, SEEK_SET);
325

    
326
        currentpos = seekhead->filepos;
327
    }
328
    av_free(seekhead->entries);
329
    av_free(seekhead);
330

    
331
    return currentpos;
332
}
333

    
334
static mkv_cues * mkv_start_cues(int64_t segment_offset)
335
{
336
    mkv_cues *cues = av_mallocz(sizeof(mkv_cues));
337
    if (cues == NULL)
338
        return NULL;
339

    
340
    cues->segment_offset = segment_offset;
341
    return cues;
342
}
343

    
344
static int mkv_add_cuepoint(mkv_cues *cues, AVPacket *pkt, int64_t cluster_pos)
345
{
346
    mkv_cuepoint *entries = cues->entries;
347

    
348
    entries = av_realloc(entries, (cues->num_entries + 1) * sizeof(mkv_cuepoint));
349
    if (entries == NULL)
350
        return AVERROR(ENOMEM);
351

    
352
    entries[cues->num_entries  ].pts = pkt->pts;
353
    entries[cues->num_entries  ].tracknum = pkt->stream_index + 1;
354
    entries[cues->num_entries++].cluster_pos = cluster_pos - cues->segment_offset;
355

    
356
    cues->entries = entries;
357
    return 0;
358
}
359

    
360
static int64_t mkv_write_cues(ByteIOContext *pb, mkv_cues *cues, int num_tracks)
361
{
362
    ebml_master cues_element;
363
    int64_t currentpos;
364
    int i, j;
365

    
366
    currentpos = url_ftell(pb);
367
    cues_element = start_ebml_master(pb, MATROSKA_ID_CUES, 0);
368

    
369
    for (i = 0; i < cues->num_entries; i++) {
370
        ebml_master cuepoint, track_positions;
371
        mkv_cuepoint *entry = &cues->entries[i];
372
        uint64_t pts = entry->pts;
373

    
374
        cuepoint = start_ebml_master(pb, MATROSKA_ID_POINTENTRY, MAX_CUEPOINT_SIZE(num_tracks));
375
        put_ebml_uint(pb, MATROSKA_ID_CUETIME, pts);
376

    
377
        // put all the entries from different tracks that have the exact same
378
        // timestamp into the same CuePoint
379
        for (j = 0; j < cues->num_entries - i && entry[j].pts == pts; j++) {
380
            track_positions = start_ebml_master(pb, MATROSKA_ID_CUETRACKPOSITION, MAX_CUETRACKPOS_SIZE);
381
            put_ebml_uint(pb, MATROSKA_ID_CUETRACK          , entry[j].tracknum   );
382
            put_ebml_uint(pb, MATROSKA_ID_CUECLUSTERPOSITION, entry[j].cluster_pos);
383
            end_ebml_master(pb, track_positions);
384
        }
385
        i += j - 1;
386
        end_ebml_master(pb, cuepoint);
387
    }
388
    end_ebml_master(pb, cues_element);
389

    
390
    av_free(cues->entries);
391
    av_free(cues);
392
    return currentpos;
393
}
394

    
395
static int put_xiph_codecpriv(AVFormatContext *s, ByteIOContext *pb, AVCodecContext *codec)
396
{
397
    uint8_t *header_start[3];
398
    int header_len[3];
399
    int first_header_size;
400
    int j;
401

    
402
    if (codec->codec_id == CODEC_ID_VORBIS)
403
        first_header_size = 30;
404
    else
405
        first_header_size = 42;
406

    
407
    if (ff_split_xiph_headers(codec->extradata, codec->extradata_size,
408
                              first_header_size, header_start, header_len) < 0) {
409
        av_log(s, AV_LOG_ERROR, "Extradata corrupt.\n");
410
        return -1;
411
    }
412

    
413
    put_byte(pb, 2);                    // number packets - 1
414
    for (j = 0; j < 2; j++) {
415
        put_xiph_size(pb, header_len[j]);
416
    }
417
    for (j = 0; j < 3; j++)
418
        put_buffer(pb, header_start[j], header_len[j]);
419

    
420
    return 0;
421
}
422

    
423
#define FLAC_STREAMINFO_SIZE 34
424

    
425
static int put_flac_codecpriv(AVFormatContext *s, ByteIOContext *pb, AVCodecContext *codec)
426
{
427
    // if the extradata_size is greater than FLAC_STREAMINFO_SIZE,
428
    // assume that it's in Matroska format already
429
    if (codec->extradata_size < FLAC_STREAMINFO_SIZE) {
430
        av_log(s, AV_LOG_ERROR, "Invalid FLAC extradata\n");
431
        return -1;
432
    } else if (codec->extradata_size == FLAC_STREAMINFO_SIZE) {
433
        // only the streaminfo packet
434
        put_buffer(pb, "fLaC", 4);
435
        put_byte(pb, 0x80);
436
        put_be24(pb, FLAC_STREAMINFO_SIZE);
437
    } else if(memcmp("fLaC", codec->extradata, 4)) {
438
        av_log(s, AV_LOG_ERROR, "Invalid FLAC extradata\n");
439
        return -1;
440
    }
441
    put_buffer(pb, codec->extradata, codec->extradata_size);
442
    return 0;
443
}
444

    
445
static void get_aac_sample_rates(AVFormatContext *s, AVCodecContext *codec, int *sample_rate, int *output_sample_rate)
446
{
447
    int sri;
448

    
449
    if (codec->extradata_size < 2) {
450
        av_log(s, AV_LOG_WARNING, "No AAC extradata, unable to determine samplerate.\n");
451
        return;
452
    }
453

    
454
    sri = ((codec->extradata[0] << 1) & 0xE) | (codec->extradata[1] >> 7);
455
    if (sri > 12) {
456
        av_log(s, AV_LOG_WARNING, "AAC samplerate index out of bounds\n");
457
        return;
458
    }
459
    *sample_rate = ff_mpeg4audio_sample_rates[sri];
460

    
461
    // if sbr, get output sample rate as well
462
    if (codec->extradata_size == 5) {
463
        sri = (codec->extradata[4] >> 3) & 0xF;
464
        if (sri > 12) {
465
            av_log(s, AV_LOG_WARNING, "AAC output samplerate index out of bounds\n");
466
            return;
467
        }
468
        *output_sample_rate = ff_mpeg4audio_sample_rates[sri];
469
    }
470
}
471

    
472
static int mkv_write_codecprivate(AVFormatContext *s, ByteIOContext *pb, AVCodecContext *codec, int native_id, int qt_id)
473
{
474
    ByteIOContext *dyn_cp;
475
    uint8_t *codecpriv;
476
    int ret, codecpriv_size;
477

    
478
    ret = url_open_dyn_buf(&dyn_cp);
479
    if(ret < 0)
480
        return ret;
481

    
482
    if (native_id) {
483
        if (codec->codec_id == CODEC_ID_VORBIS || codec->codec_id == CODEC_ID_THEORA)
484
            ret = put_xiph_codecpriv(s, dyn_cp, codec);
485
        else if (codec->codec_id == CODEC_ID_FLAC)
486
            ret = put_flac_codecpriv(s, dyn_cp, codec);
487
        else if (codec->codec_id == CODEC_ID_H264)
488
            ret = ff_isom_write_avcc(dyn_cp, codec->extradata, codec->extradata_size);
489
        else if (codec->extradata_size)
490
            put_buffer(dyn_cp, codec->extradata, codec->extradata_size);
491
    } else if (codec->codec_type == CODEC_TYPE_VIDEO) {
492
        if (qt_id) {
493
            if (!codec->codec_tag)
494
                codec->codec_tag = codec_get_tag(codec_movvideo_tags, codec->codec_id);
495
            if (codec->extradata_size)
496
                put_buffer(dyn_cp, codec->extradata, codec->extradata_size);
497
        } else {
498
        if (!codec->codec_tag)
499
            codec->codec_tag = codec_get_tag(codec_bmp_tags, codec->codec_id);
500
        if (!codec->codec_tag) {
501
            av_log(s, AV_LOG_ERROR, "No bmp codec ID found.");
502
            ret = -1;
503
        }
504

    
505
        put_bmp_header(dyn_cp, codec, codec_bmp_tags, 0);
506
        }
507

    
508
    } else if (codec->codec_type == CODEC_TYPE_AUDIO) {
509
        if (!codec->codec_tag)
510
            codec->codec_tag = codec_get_tag(codec_wav_tags, codec->codec_id);
511
        if (!codec->codec_tag) {
512
            av_log(s, AV_LOG_ERROR, "No wav codec ID found.");
513
            ret = -1;
514
        }
515

    
516
        put_wav_header(dyn_cp, codec);
517
    }
518

    
519
    codecpriv_size = url_close_dyn_buf(dyn_cp, &codecpriv);
520
    if (codecpriv_size)
521
        put_ebml_binary(pb, MATROSKA_ID_CODECPRIVATE, codecpriv, codecpriv_size);
522
    av_free(codecpriv);
523
    return ret;
524
}
525

    
526
static int mkv_write_tracks(AVFormatContext *s)
527
{
528
    MatroskaMuxContext *mkv = s->priv_data;
529
    ByteIOContext *pb = s->pb;
530
    ebml_master tracks;
531
    int i, j, ret;
532

    
533
    ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_TRACKS, url_ftell(pb));
534
    if (ret < 0) return ret;
535

    
536
    tracks = start_ebml_master(pb, MATROSKA_ID_TRACKS, 0);
537
    for (i = 0; i < s->nb_streams; i++) {
538
        AVStream *st = s->streams[i];
539
        AVCodecContext *codec = st->codec;
540
        ebml_master subinfo, track;
541
        int native_id = 0;
542
        int qt_id = 0;
543
        int bit_depth = av_get_bits_per_sample(codec->codec_id);
544
        int sample_rate = codec->sample_rate;
545
        int output_sample_rate = 0;
546

    
547
        if (!bit_depth)
548
            bit_depth = av_get_bits_per_sample_format(codec->sample_fmt);
549

    
550
        if (codec->codec_id == CODEC_ID_AAC)
551
            get_aac_sample_rates(s, codec, &sample_rate, &output_sample_rate);
552

    
553
        track = start_ebml_master(pb, MATROSKA_ID_TRACKENTRY, 0);
554
        put_ebml_uint (pb, MATROSKA_ID_TRACKNUMBER     , i + 1);
555
        put_ebml_uint (pb, MATROSKA_ID_TRACKUID        , i + 1);
556
        put_ebml_uint (pb, MATROSKA_ID_TRACKFLAGLACING , 0);    // no lacing (yet)
557

    
558
        if (st->language[0])
559
            put_ebml_string(pb, MATROSKA_ID_TRACKLANGUAGE, st->language);
560
        else
561
            put_ebml_string(pb, MATROSKA_ID_TRACKLANGUAGE, "und");
562

    
563
        put_ebml_uint(pb, MATROSKA_ID_TRACKFLAGDEFAULT, !!(st->disposition & AV_DISPOSITION_DEFAULT));
564

    
565
        // look for a codec ID string specific to mkv to use,
566
        // if none are found, use AVI codes
567
        for (j = 0; ff_mkv_codec_tags[j].id != CODEC_ID_NONE; j++) {
568
            if (ff_mkv_codec_tags[j].id == codec->codec_id) {
569
                put_ebml_string(pb, MATROSKA_ID_CODECID, ff_mkv_codec_tags[j].str);
570
                native_id = 1;
571
                break;
572
            }
573
        }
574

    
575
        switch (codec->codec_type) {
576
            case CODEC_TYPE_VIDEO:
577
                put_ebml_uint(pb, MATROSKA_ID_TRACKTYPE, MATROSKA_TRACK_TYPE_VIDEO);
578

    
579
                if (!native_id &&
580
                      codec_get_tag(codec_movvideo_tags, codec->codec_id) &&
581
                    (!codec_get_tag(codec_bmp_tags,      codec->codec_id)
582
                     || codec->codec_id == CODEC_ID_SVQ1
583
                     || codec->codec_id == CODEC_ID_SVQ3
584
                     || codec->codec_id == CODEC_ID_CINEPAK))
585
                    qt_id = 1;
586

    
587
                if (qt_id)
588
                    put_ebml_string(pb, MATROSKA_ID_CODECID, "V_QUICKTIME");
589
                else if (!native_id)
590
                    // if there is no mkv-specific codec ID, use VFW mode
591
                    put_ebml_string(pb, MATROSKA_ID_CODECID, "V_MS/VFW/FOURCC");
592

    
593
                subinfo = start_ebml_master(pb, MATROSKA_ID_TRACKVIDEO, 0);
594
                // XXX: interlace flag?
595
                put_ebml_uint (pb, MATROSKA_ID_VIDEOPIXELWIDTH , codec->width);
596
                put_ebml_uint (pb, MATROSKA_ID_VIDEOPIXELHEIGHT, codec->height);
597
                if (st->sample_aspect_ratio.num) {
598
                    int d_width = codec->width*av_q2d(st->sample_aspect_ratio);
599
                    put_ebml_uint(pb, MATROSKA_ID_VIDEODISPLAYWIDTH , d_width);
600
                    put_ebml_uint(pb, MATROSKA_ID_VIDEODISPLAYHEIGHT, codec->height);
601
                }
602
                end_ebml_master(pb, subinfo);
603
                break;
604

    
605
            case CODEC_TYPE_AUDIO:
606
                put_ebml_uint(pb, MATROSKA_ID_TRACKTYPE, MATROSKA_TRACK_TYPE_AUDIO);
607

    
608
                if (!native_id)
609
                    // no mkv-specific ID, use ACM mode
610
                    put_ebml_string(pb, MATROSKA_ID_CODECID, "A_MS/ACM");
611

    
612
                subinfo = start_ebml_master(pb, MATROSKA_ID_TRACKAUDIO, 0);
613
                put_ebml_uint  (pb, MATROSKA_ID_AUDIOCHANNELS    , codec->channels);
614
                put_ebml_float (pb, MATROSKA_ID_AUDIOSAMPLINGFREQ, sample_rate);
615
                if (output_sample_rate)
616
                    put_ebml_float(pb, MATROSKA_ID_AUDIOOUTSAMPLINGFREQ, output_sample_rate);
617
                if (bit_depth)
618
                    put_ebml_uint(pb, MATROSKA_ID_AUDIOBITDEPTH, bit_depth);
619
                end_ebml_master(pb, subinfo);
620
                break;
621

    
622
            case CODEC_TYPE_SUBTITLE:
623
                put_ebml_uint(pb, MATROSKA_ID_TRACKTYPE, MATROSKA_TRACK_TYPE_SUBTITLE);
624
                break;
625
            default:
626
                av_log(s, AV_LOG_ERROR, "Only audio, video, and subtitles are supported for Matroska.");
627
                break;
628
        }
629
        ret = mkv_write_codecprivate(s, pb, codec, native_id, qt_id);
630
        if (ret < 0) return ret;
631

    
632
        end_ebml_master(pb, track);
633

    
634
        // ms precision is the de-facto standard timescale for mkv files
635
        av_set_pts_info(st, 64, 1, 1000);
636
    }
637
    end_ebml_master(pb, tracks);
638
    return 0;
639
}
640

    
641
static int mkv_write_header(AVFormatContext *s)
642
{
643
    MatroskaMuxContext *mkv = s->priv_data;
644
    ByteIOContext *pb = s->pb;
645
    ebml_master ebml_header, segment_info;
646
    int ret;
647

    
648
    mkv->md5_ctx = av_mallocz(av_md5_size);
649
    av_md5_init(mkv->md5_ctx);
650

    
651
    ebml_header = start_ebml_master(pb, EBML_ID_HEADER, 0);
652
    put_ebml_uint   (pb, EBML_ID_EBMLVERSION        ,           1);
653
    put_ebml_uint   (pb, EBML_ID_EBMLREADVERSION    ,           1);
654
    put_ebml_uint   (pb, EBML_ID_EBMLMAXIDLENGTH    ,           4);
655
    put_ebml_uint   (pb, EBML_ID_EBMLMAXSIZELENGTH  ,           8);
656
    put_ebml_string (pb, EBML_ID_DOCTYPE            ,  "matroska");
657
    put_ebml_uint   (pb, EBML_ID_DOCTYPEVERSION     ,           2);
658
    put_ebml_uint   (pb, EBML_ID_DOCTYPEREADVERSION ,           2);
659
    end_ebml_master(pb, ebml_header);
660

    
661
    mkv->segment = start_ebml_master(pb, MATROSKA_ID_SEGMENT, 0);
662
    mkv->segment_offset = url_ftell(pb);
663

    
664
    // we write 2 seek heads - one at the end of the file to point to each
665
    // cluster, and one at the beginning to point to all other level one
666
    // elements (including the seek head at the end of the file), which
667
    // isn't more than 10 elements if we only write one of each other
668
    // currently defined level 1 element
669
    mkv->main_seekhead    = mkv_start_seekhead(pb, mkv->segment_offset, 10);
670
    mkv->cluster_seekhead = mkv_start_seekhead(pb, mkv->segment_offset, 0);
671
    if (mkv->main_seekhead == NULL || mkv->cluster_seekhead == NULL)
672
        return AVERROR(ENOMEM);
673

    
674
    ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_INFO, url_ftell(pb));
675
    if (ret < 0) return ret;
676

    
677
    segment_info = start_ebml_master(pb, MATROSKA_ID_INFO, 0);
678
    put_ebml_uint(pb, MATROSKA_ID_TIMECODESCALE, 1000000);
679
    if (strlen(s->title))
680
        put_ebml_string(pb, MATROSKA_ID_TITLE, s->title);
681
    if (!(s->streams[0]->codec->flags & CODEC_FLAG_BITEXACT)) {
682
        put_ebml_string(pb, MATROSKA_ID_MUXINGAPP , LIBAVFORMAT_IDENT);
683
        put_ebml_string(pb, MATROSKA_ID_WRITINGAPP, LIBAVFORMAT_IDENT);
684

    
685
        // reserve space to write the segment UID later
686
        mkv->segment_uid = url_ftell(pb);
687
        put_ebml_void(pb, 19);
688
    }
689

    
690
    // reserve space for the duration
691
    mkv->duration = 0;
692
    mkv->duration_offset = url_ftell(pb);
693
    put_ebml_void(pb, 11);                  // assumes double-precision float to be written
694
    end_ebml_master(pb, segment_info);
695

    
696
    ret = mkv_write_tracks(s);
697
    if (ret < 0) return ret;
698

    
699
    ret = mkv_add_seekhead_entry(mkv->cluster_seekhead, MATROSKA_ID_CLUSTER, url_ftell(pb));
700
    if (ret < 0) return ret;
701

    
702
    mkv->cluster_pos = url_ftell(pb);
703
    mkv->cluster = start_ebml_master(pb, MATROSKA_ID_CLUSTER, 0);
704
    put_ebml_uint(pb, MATROSKA_ID_CLUSTERTIMECODE, 0);
705
    mkv->cluster_pts = 0;
706

    
707
    mkv->cues = mkv_start_cues(mkv->segment_offset);
708
    if (mkv->cues == NULL)
709
        return AVERROR(ENOMEM);
710

    
711
    return 0;
712
}
713

    
714
static int mkv_blockgroup_size(int pkt_size)
715
{
716
    int size = pkt_size + 4;
717
    size += ebml_num_size(size);
718
    size += 2;              // EBML ID for block and block duration
719
    size += 8;              // max size of block duration
720
    size += ebml_num_size(size);
721
    size += 1;              // blockgroup EBML ID
722
    return size;
723
}
724

    
725
static int ass_get_duration(const uint8_t *p)
726
{
727
    int sh, sm, ss, sc, eh, em, es, ec;
728
    uint64_t start, end;
729

    
730
    if (sscanf(p, "%*[^,],%d:%d:%d%*c%d,%d:%d:%d%*c%d",
731
               &sh, &sm, &ss, &sc, &eh, &em, &es, &ec) != 8)
732
        return 0;
733
    start = 3600000*sh + 60000*sm + 1000*ss + 10*sc;
734
    end   = 3600000*eh + 60000*em + 1000*es + 10*ec;
735
    return end - start;
736
}
737

    
738
static int mkv_write_ass_blocks(AVFormatContext *s, AVPacket *pkt)
739
{
740
    MatroskaMuxContext *mkv = s->priv_data;
741
    ByteIOContext *pb = s->pb;
742
    int i, layer = 0, max_duration = 0, size, line_size, data_size = pkt->size;
743
    uint8_t *start, *end, *data = pkt->data;
744
    ebml_master blockgroup;
745
    char buffer[2048];
746

    
747
    while (data_size) {
748
        int duration = ass_get_duration(data);
749
        max_duration = FFMAX(duration, max_duration);
750
        end = memchr(data, '\n', data_size);
751
        size = line_size = end ? end-data+1 : data_size;
752
        size -= end ? (end[-1]=='\r')+1 : 0;
753
        start = data;
754
        for (i=0; i<3; i++, start++)
755
            if (!(start = memchr(start, ',', size-(start-data))))
756
                return max_duration;
757
        size -= start - data;
758
        sscanf(data, "Dialogue: %d,", &layer);
759
        i = snprintf(buffer, sizeof(buffer), "%"PRId64",%d,",
760
                     s->streams[pkt->stream_index]->nb_frames++, layer);
761
        size = FFMIN(i+size, sizeof(buffer));
762
        memcpy(buffer+i, start, size-i);
763

    
764
        av_log(s, AV_LOG_DEBUG, "Writing block at offset %" PRIu64 ", size %d, "
765
               "pts %" PRId64 ", duration %d\n",
766
               url_ftell(pb), size, pkt->pts, duration);
767
        blockgroup = start_ebml_master(pb, MATROSKA_ID_BLOCKGROUP, mkv_blockgroup_size(size));
768
        put_ebml_id(pb, MATROSKA_ID_BLOCK);
769
        put_ebml_num(pb, size+4, 0);
770
        put_byte(pb, 0x80 | (pkt->stream_index + 1));     // this assumes stream_index is less than 126
771
        put_be16(pb, pkt->pts - mkv->cluster_pts);
772
        put_byte(pb, 0);
773
        put_buffer(pb, buffer, size);
774
        put_ebml_uint(pb, MATROSKA_ID_BLOCKDURATION, duration);
775
        end_ebml_master(pb, blockgroup);
776

    
777
        data += line_size;
778
        data_size -= line_size;
779
    }
780

    
781
    return max_duration;
782
}
783

    
784
static void mkv_write_block(AVFormatContext *s, unsigned int blockid, AVPacket *pkt, int flags)
785
{
786
    MatroskaMuxContext *mkv = s->priv_data;
787
    ByteIOContext *pb = s->pb;
788
    AVCodecContext *codec = s->streams[pkt->stream_index]->codec;
789

    
790
    av_log(s, AV_LOG_DEBUG, "Writing block at offset %" PRIu64 ", size %d, "
791
           "pts %" PRId64 ", dts %" PRId64 ", duration %d, flags %d\n",
792
           url_ftell(pb), pkt->size, pkt->pts, pkt->dts, pkt->duration, flags);
793
    put_ebml_id(pb, blockid);
794
    put_ebml_num(pb, pkt->size+4, 0);
795
    put_byte(pb, 0x80 | (pkt->stream_index + 1));     // this assumes stream_index is less than 126
796
    put_be16(pb, pkt->pts - mkv->cluster_pts);
797
    put_byte(pb, flags);
798
    if (codec->codec_id == CODEC_ID_H264 &&
799
        codec->extradata_size > 0 && AV_RB32(codec->extradata) == 0x00000001) {
800
        /* from x264 or from bytestream h264 */
801
        /* nal reformating needed */
802
        ff_avc_parse_nal_units(pb, pkt->data, pkt->size);
803
    } else {
804
        put_buffer(pb, pkt->data, pkt->size);
805
    }
806
}
807

    
808
static int mkv_write_packet(AVFormatContext *s, AVPacket *pkt)
809
{
810
    MatroskaMuxContext *mkv = s->priv_data;
811
    ByteIOContext *pb = s->pb;
812
    AVCodecContext *codec = s->streams[pkt->stream_index]->codec;
813
    int keyframe = !!(pkt->flags & PKT_FLAG_KEY);
814
    int duration = pkt->duration;
815
    int ret;
816

    
817
    // start a new cluster every 5 MB or 5 sec
818
    if (url_ftell(pb) > mkv->cluster_pos + 5*1024*1024 || pkt->pts > mkv->cluster_pts + 5000) {
819
        av_log(s, AV_LOG_DEBUG, "Starting new cluster at offset %" PRIu64
820
               " bytes, pts %" PRIu64 "\n", url_ftell(pb), pkt->pts);
821
        end_ebml_master(pb, mkv->cluster);
822

    
823
        ret = mkv_add_seekhead_entry(mkv->cluster_seekhead, MATROSKA_ID_CLUSTER, url_ftell(pb));
824
        if (ret < 0) return ret;
825

    
826
        mkv->cluster_pos = url_ftell(pb);
827
        mkv->cluster = start_ebml_master(pb, MATROSKA_ID_CLUSTER, 0);
828
        put_ebml_uint(pb, MATROSKA_ID_CLUSTERTIMECODE, pkt->pts);
829
        mkv->cluster_pts = pkt->pts;
830
        av_md5_update(mkv->md5_ctx, pkt->data, FFMIN(200, pkt->size));
831
    }
832

    
833
    if (codec->codec_type != CODEC_TYPE_SUBTITLE) {
834
        mkv_write_block(s, MATROSKA_ID_SIMPLEBLOCK, pkt, keyframe << 7);
835
    } else if (codec->codec_id == CODEC_ID_SSA) {
836
        duration = mkv_write_ass_blocks(s, pkt);
837
    } else {
838
        ebml_master blockgroup = start_ebml_master(pb, MATROSKA_ID_BLOCKGROUP, mkv_blockgroup_size(pkt->size));
839
        duration = pkt->convergence_duration;
840
        mkv_write_block(s, MATROSKA_ID_BLOCK, pkt, 0);
841
        put_ebml_uint(pb, MATROSKA_ID_BLOCKDURATION, duration);
842
        end_ebml_master(pb, blockgroup);
843
    }
844

    
845
    if (codec->codec_type == CODEC_TYPE_VIDEO && keyframe) {
846
        ret = mkv_add_cuepoint(mkv->cues, pkt, mkv->cluster_pos);
847
        if (ret < 0) return ret;
848
    }
849

    
850
    mkv->duration = FFMAX(mkv->duration, pkt->pts + duration);
851
    return 0;
852
}
853

    
854
static int mkv_write_trailer(AVFormatContext *s)
855
{
856
    MatroskaMuxContext *mkv = s->priv_data;
857
    ByteIOContext *pb = s->pb;
858
    int64_t currentpos, second_seekhead, cuespos;
859
    int ret;
860

    
861
    end_ebml_master(pb, mkv->cluster);
862

    
863
    if (!url_is_streamed(pb)) {
864
        cuespos = mkv_write_cues(pb, mkv->cues, s->nb_streams);
865
        second_seekhead = mkv_write_seekhead(pb, mkv->cluster_seekhead);
866

    
867
        ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_CUES    , cuespos);
868
        if (ret < 0) return ret;
869
        ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_SEEKHEAD, second_seekhead);
870
        if (ret < 0) return ret;
871
        mkv_write_seekhead(pb, mkv->main_seekhead);
872

    
873
        // update the duration
874
        av_log(s, AV_LOG_DEBUG, "end duration = %" PRIu64 "\n", mkv->duration);
875
        currentpos = url_ftell(pb);
876
        url_fseek(pb, mkv->duration_offset, SEEK_SET);
877
        put_ebml_float(pb, MATROSKA_ID_DURATION, mkv->duration);
878

    
879
        // write the md5sum of some frames as the segment UID
880
        if (!(s->streams[0]->codec->flags & CODEC_FLAG_BITEXACT)) {
881
            uint8_t segment_uid[16];
882
            av_md5_final(mkv->md5_ctx, segment_uid);
883
            url_fseek(pb, mkv->segment_uid, SEEK_SET);
884
            put_ebml_binary(pb, MATROSKA_ID_SEGMENTUID, segment_uid, 16);
885
        }
886
        url_fseek(pb, currentpos, SEEK_SET);
887
    }
888

    
889
    end_ebml_master(pb, mkv->segment);
890
    av_free(mkv->md5_ctx);
891
    return 0;
892
}
893

    
894
AVOutputFormat matroska_muxer = {
895
    "matroska",
896
    NULL_IF_CONFIG_SMALL("Matroska file format"),
897
    "video/x-matroska",
898
    "mkv",
899
    sizeof(MatroskaMuxContext),
900
    CODEC_ID_MP2,
901
    CODEC_ID_MPEG4,
902
    mkv_write_header,
903
    mkv_write_packet,
904
    mkv_write_trailer,
905
    .flags = AVFMT_GLOBALHEADER,
906
    .codec_tag = (const AVCodecTag* const []){codec_bmp_tags, codec_wav_tags, 0},
907
    .subtitle_codec = CODEC_ID_TEXT,
908
};
909

    
910
AVOutputFormat matroska_audio_muxer = {
911
    "matroska",
912
    NULL_IF_CONFIG_SMALL("Matroska file format"),
913
    "audio/x-matroska",
914
    "mka",
915
    sizeof(MatroskaMuxContext),
916
    CODEC_ID_MP2,
917
    CODEC_ID_NONE,
918
    mkv_write_header,
919
    mkv_write_packet,
920
    mkv_write_trailer,
921
    .flags = AVFMT_GLOBALHEADER,
922
    .codec_tag = (const AVCodecTag* const []){codec_wav_tags, 0},
923
};