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ffmpeg / libavformat / matroskaenc.c @ abce34d9

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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,
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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
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 * 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

    
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#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/md5.h"
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#include "libavcodec/xiph.h"
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#include "libavcodec/mpeg4audio.h"
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typedef struct ebml_master {
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    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;
35

    
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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;
40

    
41
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;
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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;
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typedef struct {
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    int64_t         segment_offset;
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    mkv_cuepoint    *entries;
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    int             num_entries;
60
} mkv_cues;
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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;
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    struct AVMD5    *md5_ctx;
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} MatroskaMuxContext;
77

    
78

    
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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 */
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#define MAX_SEEKENTRY_SIZE 21
82

    
83
/** per-cuepoint-track - 3 1-byte EBML IDs, 3 1-byte EBML sizes, 2
84
 * 8-byte uint max */
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#define MAX_CUETRACKPOS_SIZE 22
86

    
87
/** per-cuepoint - 2 1-byte EBML IDs, 2 1-byte EBML sizes, 8-byte uint max */
88
#define MAX_CUEPOINT_SIZE(num_tracks) 12 + MAX_CUETRACKPOS_SIZE*num_tracks
89

    
90

    
91
static int ebml_id_size(unsigned int id)
92
{
93
    return (av_log2(id+1)-1)/7+1;
94
}
95

    
96
static void put_ebml_id(ByteIOContext *pb, unsigned int id)
97
{
98
    int i = ebml_id_size(id);
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    while (i--)
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        put_byte(pb, id >> (i*8));
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}
102

    
103
/**
104
 * Write an EBML size meaning "unknown size".
105
 *
106
 * @param bytes The number of bytes the size should occupy (maximum: 8).
107
 */
108
static void put_ebml_size_unknown(ByteIOContext *pb, int bytes)
109
{
110
    assert(bytes <= 8);
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    put_byte(pb, 0x1ff >> bytes);
112
    while (--bytes)
113
        put_byte(pb, 0xff);
114
}
115

    
116
/**
117
 * Calculate how many bytes are needed to represent a given number in EBML.
118
 */
119
static int ebml_num_size(uint64_t num)
120
{
121
    int bytes = 1;
122
    while ((num+1) >> bytes*7) bytes++;
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    return bytes;
124
}
125

    
126
/**
127
 * Write a number in EBML variable length format.
128
 *
129
 * @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.
131
 */
132
static void put_ebml_num(ByteIOContext *pb, uint64_t num, int bytes)
133
{
134
    int i, needed_bytes = ebml_num_size(num);
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136
    // sizes larger than this are currently undefined in EBML
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    assert(num < (1ULL<<56)-1);
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139
    if (bytes == 0)
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        // 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.
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    assert(bytes >= needed_bytes);
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146
    num |= 1ULL << bytes*7;
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    for (i = bytes - 1; i >= 0; i--)
148
        put_byte(pb, num >> i*8);
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}
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151
static void put_ebml_uint(ByteIOContext *pb, unsigned int elementid, uint64_t val)
152
{
153
    int i, bytes = 1;
154
    uint64_t tmp = val;
155
    while (tmp>>=8) bytes++;
156

    
157
    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);
161
}
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163
static void put_ebml_float(ByteIOContext *pb, unsigned int elementid, double val)
164
{
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    put_ebml_id(pb, elementid);
166
    put_ebml_num(pb, 8, 0);
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    put_be64(pb, av_dbl2int(val));
168
}
169

    
170
static void put_ebml_binary(ByteIOContext *pb, unsigned int elementid,
171
                            const uint8_t *buf, int size)
172
{
173
    put_ebml_id(pb, elementid);
174
    put_ebml_num(pb, size, 0);
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    put_buffer(pb, buf, size);
176
}
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178
static void put_ebml_string(ByteIOContext *pb, unsigned int elementid, const char *str)
179
{
180
    put_ebml_binary(pb, elementid, str, strlen(str));
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}
182

    
183
/**
184
 * Writes a void element of a given size. Useful for reserving space in
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 * the file to be written to later.
186
 *
187
 * @param size The number of bytes to reserve, which must be at least 2.
188
 */
189
static void put_ebml_void(ByteIOContext *pb, uint64_t size)
190
{
191
    int64_t currentpos = url_ftell(pb);
192

    
193
    assert(size >= 2);
194

    
195
    put_ebml_id(pb, EBML_ID_VOID);
196
    // 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
199
    if (size < 10)
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        put_ebml_num(pb, size-1, 0);
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    else
202
        put_ebml_num(pb, size-9, 8);
203
    while(url_ftell(pb) < currentpos + size)
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        put_byte(pb, 0);
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}
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207
static ebml_master start_ebml_master(ByteIOContext *pb, unsigned int elementid, uint64_t expectedsize)
208
{
209
    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)
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{
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    int64_t pos = url_ftell(pb);
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    // leave the unknown size for masters when streaming
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    if (url_is_streamed(pb))
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        return;
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223
    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);
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}
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static void put_xiph_size(ByteIOContext *pb, int size)
229
{
230
    int i;
231
    for (i = 0; i < size / 255; i++)
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        put_byte(pb, 255);
233
    put_byte(pb, size % 255);
234
}
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236
/**
237
 * Initialize a mkv_seekhead element to be ready to index level 1 Matroska
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 * elements. If a maximum number of elements is specified, enough space
239
 * will be reserved at the current file location to write a seek head of
240
 * that size.
241
 *
242
 * @param segment_offset The absolute offset to the position in the file
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 *                       where the segment begins.
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 * @param numelements The maximum number of elements that will be indexed
245
 *                    by this seek head, 0 if unlimited.
246
 */
247
static mkv_seekhead * mkv_start_seekhead(ByteIOContext *pb, int64_t segment_offset, int numelements)
248
{
249
    mkv_seekhead *new_seekhead = av_mallocz(sizeof(mkv_seekhead));
250
    if (new_seekhead == NULL)
251
        return NULL;
252

    
253
    new_seekhead->segment_offset = segment_offset;
254

    
255
    if (numelements > 0) {
256
        new_seekhead->filepos = url_ftell(pb);
257
        // 21 bytes max for a seek entry, 10 bytes max for the SeekHead ID
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        // and size, and 3 bytes to guarantee that an EBML void element
259
        // will fit afterwards
260
        new_seekhead->reserved_size = numelements * MAX_SEEKENTRY_SIZE + 13;
261
        new_seekhead->max_entries = numelements;
262
        put_ebml_void(pb, new_seekhead->reserved_size);
263
    }
264
    return new_seekhead;
265
}
266

    
267
static int mkv_add_seekhead_entry(mkv_seekhead *seekhead, unsigned int elementid, uint64_t filepos)
268
{
269
    mkv_seekhead_entry *entries = seekhead->entries;
270

    
271
    // don't store more elements than we reserved space for
272
    if (seekhead->max_entries > 0 && seekhead->max_entries <= seekhead->num_entries)
273
        return -1;
274

    
275
    entries = av_realloc(entries, (seekhead->num_entries + 1) * sizeof(mkv_seekhead_entry));
276
    if (entries == NULL)
277
        return AVERROR(ENOMEM);
278

    
279
    entries[seekhead->num_entries  ].elementid = elementid;
280
    entries[seekhead->num_entries++].segmentpos = filepos - seekhead->segment_offset;
281

    
282
    seekhead->entries = entries;
283
    return 0;
284
}
285

    
286
/**
287
 * Write the seek head to the file and free it. If a maximum number of
288
 * elements was specified to mkv_start_seekhead(), the seek head will
289
 * be written at the location reserved for it. Otherwise, it is written
290
 * at the current location in the file.
291
 *
292
 * @return The file offset where the seekhead was written.
293
 */
294
static int64_t mkv_write_seekhead(ByteIOContext *pb, mkv_seekhead *seekhead)
295
{
296
    ebml_master metaseek, seekentry;
297
    int64_t currentpos;
298
    int i;
299

    
300
    currentpos = url_ftell(pb);
301

    
302
    if (seekhead->reserved_size > 0)
303
        url_fseek(pb, seekhead->filepos, SEEK_SET);
304

    
305
    metaseek = start_ebml_master(pb, MATROSKA_ID_SEEKHEAD, seekhead->reserved_size);
306
    for (i = 0; i < seekhead->num_entries; i++) {
307
        mkv_seekhead_entry *entry = &seekhead->entries[i];
308

    
309
        seekentry = start_ebml_master(pb, MATROSKA_ID_SEEKENTRY, MAX_SEEKENTRY_SIZE);
310

    
311
        put_ebml_id(pb, MATROSKA_ID_SEEKID);
312
        put_ebml_num(pb, ebml_id_size(entry->elementid), 0);
313
        put_ebml_id(pb, entry->elementid);
314

    
315
        put_ebml_uint(pb, MATROSKA_ID_SEEKPOSITION, entry->segmentpos);
316
        end_ebml_master(pb, seekentry);
317
    }
318
    end_ebml_master(pb, metaseek);
319

    
320
    if (seekhead->reserved_size > 0) {
321
        uint64_t remaining = seekhead->filepos + seekhead->reserved_size - url_ftell(pb);
322
        put_ebml_void(pb, remaining);
323
        url_fseek(pb, currentpos, SEEK_SET);
324

    
325
        currentpos = seekhead->filepos;
326
    }
327
    av_free(seekhead->entries);
328
    av_free(seekhead);
329

    
330
    return currentpos;
331
}
332

    
333
static mkv_cues * mkv_start_cues(int64_t segment_offset)
334
{
335
    mkv_cues *cues = av_mallocz(sizeof(mkv_cues));
336
    if (cues == NULL)
337
        return NULL;
338

    
339
    cues->segment_offset = segment_offset;
340
    return cues;
341
}
342

    
343
static int mkv_add_cuepoint(mkv_cues *cues, AVPacket *pkt, int64_t cluster_pos)
344
{
345
    mkv_cuepoint *entries = cues->entries;
346

    
347
    entries = av_realloc(entries, (cues->num_entries + 1) * sizeof(mkv_cuepoint));
348
    if (entries == NULL)
349
        return AVERROR(ENOMEM);
350

    
351
    entries[cues->num_entries  ].pts = pkt->pts;
352
    entries[cues->num_entries  ].tracknum = pkt->stream_index + 1;
353
    entries[cues->num_entries++].cluster_pos = cluster_pos - cues->segment_offset;
354

    
355
    cues->entries = entries;
356
    return 0;
357
}
358

    
359
static int64_t mkv_write_cues(ByteIOContext *pb, mkv_cues *cues, int num_tracks)
360
{
361
    ebml_master cues_element;
362
    int64_t currentpos;
363
    int i, j;
364

    
365
    currentpos = url_ftell(pb);
366
    cues_element = start_ebml_master(pb, MATROSKA_ID_CUES, 0);
367

    
368
    for (i = 0; i < cues->num_entries; i++) {
369
        ebml_master cuepoint, track_positions;
370
        mkv_cuepoint *entry = &cues->entries[i];
371
        uint64_t pts = entry->pts;
372

    
373
        cuepoint = start_ebml_master(pb, MATROSKA_ID_POINTENTRY, MAX_CUEPOINT_SIZE(num_tracks));
374
        put_ebml_uint(pb, MATROSKA_ID_CUETIME, pts);
375

    
376
        // put all the entries from different tracks that have the exact same
377
        // timestamp into the same CuePoint
378
        for (j = 0; j < cues->num_entries - i && entry[j].pts == pts; j++) {
379
            track_positions = start_ebml_master(pb, MATROSKA_ID_CUETRACKPOSITION, MAX_CUETRACKPOS_SIZE);
380
            put_ebml_uint(pb, MATROSKA_ID_CUETRACK          , entry[j].tracknum   );
381
            put_ebml_uint(pb, MATROSKA_ID_CUECLUSTERPOSITION, entry[j].cluster_pos);
382
            end_ebml_master(pb, track_positions);
383
        }
384
        i += j - 1;
385
        end_ebml_master(pb, cuepoint);
386
    }
387
    end_ebml_master(pb, cues_element);
388

    
389
    av_free(cues->entries);
390
    av_free(cues);
391
    return currentpos;
392
}
393

    
394
static int put_xiph_codecpriv(AVFormatContext *s, ByteIOContext *pb, AVCodecContext *codec)
395
{
396
    uint8_t *header_start[3];
397
    int header_len[3];
398
    int first_header_size;
399
    int j;
400

    
401
    if (codec->codec_id == CODEC_ID_VORBIS)
402
        first_header_size = 30;
403
    else
404
        first_header_size = 42;
405

    
406
    if (ff_split_xiph_headers(codec->extradata, codec->extradata_size,
407
                              first_header_size, header_start, header_len) < 0) {
408
        av_log(s, AV_LOG_ERROR, "Extradata corrupt.\n");
409
        return -1;
410
    }
411

    
412
    put_byte(pb, 2);                    // number packets - 1
413
    for (j = 0; j < 2; j++) {
414
        put_xiph_size(pb, header_len[j]);
415
    }
416
    for (j = 0; j < 3; j++)
417
        put_buffer(pb, header_start[j], header_len[j]);
418

    
419
    return 0;
420
}
421

    
422
#define FLAC_STREAMINFO_SIZE 34
423

    
424
static int put_flac_codecpriv(AVFormatContext *s, ByteIOContext *pb, AVCodecContext *codec)
425
{
426
    // if the extradata_size is greater than FLAC_STREAMINFO_SIZE,
427
    // assume that it's in Matroska format already
428
    if (codec->extradata_size < FLAC_STREAMINFO_SIZE) {
429
        av_log(s, AV_LOG_ERROR, "Invalid FLAC extradata\n");
430
        return -1;
431
    } else if (codec->extradata_size == FLAC_STREAMINFO_SIZE) {
432
        // only the streaminfo packet
433
        put_buffer(pb, "fLaC", 4);
434
        put_byte(pb, 0x80);
435
        put_be24(pb, FLAC_STREAMINFO_SIZE);
436
    } else if(memcmp("fLaC", codec->extradata, 4)) {
437
        av_log(s, AV_LOG_ERROR, "Invalid FLAC extradata\n");
438
        return -1;
439
    }
440
    put_buffer(pb, codec->extradata, codec->extradata_size);
441
    return 0;
442
}
443

    
444
static void get_aac_sample_rates(AVFormatContext *s, AVCodecContext *codec, int *sample_rate, int *output_sample_rate)
445
{
446
    int sri;
447

    
448
    if (codec->extradata_size < 2) {
449
        av_log(s, AV_LOG_WARNING, "No AAC extradata, unable to determine samplerate.\n");
450
        return;
451
    }
452

    
453
    sri = ((codec->extradata[0] << 1) & 0xE) | (codec->extradata[1] >> 7);
454
    if (sri > 12) {
455
        av_log(s, AV_LOG_WARNING, "AAC samplerate index out of bounds\n");
456
        return;
457
    }
458
    *sample_rate = ff_mpeg4audio_sample_rates[sri];
459

    
460
    // if sbr, get output sample rate as well
461
    if (codec->extradata_size == 5) {
462
        sri = (codec->extradata[4] >> 3) & 0xF;
463
        if (sri > 12) {
464
            av_log(s, AV_LOG_WARNING, "AAC output samplerate index out of bounds\n");
465
            return;
466
        }
467
        *output_sample_rate = ff_mpeg4audio_sample_rates[sri];
468
    }
469
}
470

    
471
static int mkv_write_codecprivate(AVFormatContext *s, ByteIOContext *pb, AVCodecContext *codec, int native_id, int qt_id)
472
{
473
    ByteIOContext *dyn_cp;
474
    uint8_t *codecpriv;
475
    int ret, codecpriv_size;
476

    
477
    ret = url_open_dyn_buf(&dyn_cp);
478
    if(ret < 0)
479
        return ret;
480

    
481
    if (native_id) {
482
        if (codec->codec_id == CODEC_ID_VORBIS || codec->codec_id == CODEC_ID_THEORA)
483
            ret = put_xiph_codecpriv(s, dyn_cp, codec);
484
        else if (codec->codec_id == CODEC_ID_FLAC)
485
            ret = put_flac_codecpriv(s, dyn_cp, codec);
486
        else if (codec->codec_id == CODEC_ID_H264)
487
            ret = ff_isom_write_avcc(dyn_cp, codec->extradata, codec->extradata_size);
488
        else if (codec->extradata_size)
489
            put_buffer(dyn_cp, codec->extradata, codec->extradata_size);
490
    } else if (codec->codec_type == CODEC_TYPE_VIDEO) {
491
        if (qt_id) {
492
            if (!codec->codec_tag)
493
                codec->codec_tag = codec_get_tag(codec_movvideo_tags, codec->codec_id);
494
            if (codec->extradata_size)
495
                put_buffer(dyn_cp, codec->extradata, codec->extradata_size);
496
        } else {
497
        if (!codec->codec_tag)
498
            codec->codec_tag = codec_get_tag(codec_bmp_tags, codec->codec_id);
499
        if (!codec->codec_tag) {
500
            av_log(s, AV_LOG_ERROR, "No bmp codec ID found.");
501
            ret = -1;
502
        }
503

    
504
        put_bmp_header(dyn_cp, codec, codec_bmp_tags, 0);
505
        }
506

    
507
    } else if (codec->codec_type == CODEC_TYPE_AUDIO) {
508
        if (!codec->codec_tag)
509
            codec->codec_tag = codec_get_tag(codec_wav_tags, codec->codec_id);
510
        if (!codec->codec_tag) {
511
            av_log(s, AV_LOG_ERROR, "No wav codec ID found.");
512
            ret = -1;
513
        }
514

    
515
        put_wav_header(dyn_cp, codec);
516
    }
517

    
518
    codecpriv_size = url_close_dyn_buf(dyn_cp, &codecpriv);
519
    if (codecpriv_size)
520
        put_ebml_binary(pb, MATROSKA_ID_CODECPRIVATE, codecpriv, codecpriv_size);
521
    av_free(codecpriv);
522
    return ret;
523
}
524

    
525
static int mkv_write_tracks(AVFormatContext *s)
526
{
527
    MatroskaMuxContext *mkv = s->priv_data;
528
    ByteIOContext *pb = s->pb;
529
    ebml_master tracks;
530
    int i, j, ret;
531

    
532
    ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_TRACKS, url_ftell(pb));
533
    if (ret < 0) return ret;
534

    
535
    tracks = start_ebml_master(pb, MATROSKA_ID_TRACKS, 0);
536
    for (i = 0; i < s->nb_streams; i++) {
537
        AVStream *st = s->streams[i];
538
        AVCodecContext *codec = st->codec;
539
        ebml_master subinfo, track;
540
        int native_id = 0;
541
        int qt_id = 0;
542
        int bit_depth = av_get_bits_per_sample(codec->codec_id);
543
        int sample_rate = codec->sample_rate;
544
        int output_sample_rate = 0;
545

    
546
        if (!bit_depth)
547
            bit_depth = av_get_bits_per_sample_format(codec->sample_fmt);
548

    
549
        if (codec->codec_id == CODEC_ID_AAC)
550
            get_aac_sample_rates(s, codec, &sample_rate, &output_sample_rate);
551

    
552
        track = start_ebml_master(pb, MATROSKA_ID_TRACKENTRY, 0);
553
        put_ebml_uint (pb, MATROSKA_ID_TRACKNUMBER     , i + 1);
554
        put_ebml_uint (pb, MATROSKA_ID_TRACKUID        , i + 1);
555
        put_ebml_uint (pb, MATROSKA_ID_TRACKFLAGLACING , 0);    // no lacing (yet)
556

    
557
        if (st->language[0])
558
            put_ebml_string(pb, MATROSKA_ID_TRACKLANGUAGE, st->language);
559
        else
560
            put_ebml_string(pb, MATROSKA_ID_TRACKLANGUAGE, "und");
561

    
562
        put_ebml_uint(pb, MATROSKA_ID_TRACKFLAGDEFAULT, !!(st->disposition & AV_DISPOSITION_DEFAULT));
563

    
564
        // look for a codec ID string specific to mkv to use,
565
        // if none are found, use AVI codes
566
        for (j = 0; ff_mkv_codec_tags[j].id != CODEC_ID_NONE; j++) {
567
            if (ff_mkv_codec_tags[j].id == codec->codec_id) {
568
                put_ebml_string(pb, MATROSKA_ID_CODECID, ff_mkv_codec_tags[j].str);
569
                native_id = 1;
570
                break;
571
            }
572
        }
573

    
574
        switch (codec->codec_type) {
575
            case CODEC_TYPE_VIDEO:
576
                put_ebml_uint(pb, MATROSKA_ID_TRACKTYPE, MATROSKA_TRACK_TYPE_VIDEO);
577

    
578
                if (!native_id &&
579
                      codec_get_tag(codec_movvideo_tags, codec->codec_id) &&
580
                    (!codec_get_tag(codec_bmp_tags,      codec->codec_id)
581
                     || codec->codec_id == CODEC_ID_SVQ1
582
                     || codec->codec_id == CODEC_ID_SVQ3
583
                     || codec->codec_id == CODEC_ID_CINEPAK))
584
                    qt_id = 1;
585

    
586
                if (qt_id)
587
                    put_ebml_string(pb, MATROSKA_ID_CODECID, "V_QUICKTIME");
588
                else if (!native_id)
589
                    // if there is no mkv-specific codec ID, use VFW mode
590
                    put_ebml_string(pb, MATROSKA_ID_CODECID, "V_MS/VFW/FOURCC");
591

    
592
                subinfo = start_ebml_master(pb, MATROSKA_ID_TRACKVIDEO, 0);
593
                // XXX: interlace flag?
594
                put_ebml_uint (pb, MATROSKA_ID_VIDEOPIXELWIDTH , codec->width);
595
                put_ebml_uint (pb, MATROSKA_ID_VIDEOPIXELHEIGHT, codec->height);
596
                if (st->sample_aspect_ratio.num) {
597
                    int d_width = codec->width*av_q2d(st->sample_aspect_ratio);
598
                    put_ebml_uint(pb, MATROSKA_ID_VIDEODISPLAYWIDTH , d_width);
599
                    put_ebml_uint(pb, MATROSKA_ID_VIDEODISPLAYHEIGHT, codec->height);
600
                }
601
                end_ebml_master(pb, subinfo);
602
                break;
603

    
604
            case CODEC_TYPE_AUDIO:
605
                put_ebml_uint(pb, MATROSKA_ID_TRACKTYPE, MATROSKA_TRACK_TYPE_AUDIO);
606

    
607
                if (!native_id)
608
                    // no mkv-specific ID, use ACM mode
609
                    put_ebml_string(pb, MATROSKA_ID_CODECID, "A_MS/ACM");
610

    
611
                subinfo = start_ebml_master(pb, MATROSKA_ID_TRACKAUDIO, 0);
612
                put_ebml_uint  (pb, MATROSKA_ID_AUDIOCHANNELS    , codec->channels);
613
                put_ebml_float (pb, MATROSKA_ID_AUDIOSAMPLINGFREQ, sample_rate);
614
                if (output_sample_rate)
615
                    put_ebml_float(pb, MATROSKA_ID_AUDIOOUTSAMPLINGFREQ, output_sample_rate);
616
                if (bit_depth)
617
                    put_ebml_uint(pb, MATROSKA_ID_AUDIOBITDEPTH, bit_depth);
618
                end_ebml_master(pb, subinfo);
619
                break;
620

    
621
            case CODEC_TYPE_SUBTITLE:
622
                put_ebml_uint(pb, MATROSKA_ID_TRACKTYPE, MATROSKA_TRACK_TYPE_SUBTITLE);
623
                break;
624
            default:
625
                av_log(s, AV_LOG_ERROR, "Only audio, video, and subtitles are supported for Matroska.");
626
                break;
627
        }
628
        ret = mkv_write_codecprivate(s, pb, codec, native_id, qt_id);
629
        if (ret < 0) return ret;
630

    
631
        end_ebml_master(pb, track);
632

    
633
        // ms precision is the de-facto standard timescale for mkv files
634
        av_set_pts_info(st, 64, 1, 1000);
635
    }
636
    end_ebml_master(pb, tracks);
637
    return 0;
638
}
639

    
640
static int mkv_write_header(AVFormatContext *s)
641
{
642
    MatroskaMuxContext *mkv = s->priv_data;
643
    ByteIOContext *pb = s->pb;
644
    ebml_master ebml_header, segment_info;
645
    int ret;
646

    
647
    mkv->md5_ctx = av_mallocz(av_md5_size);
648
    av_md5_init(mkv->md5_ctx);
649

    
650
    ebml_header = start_ebml_master(pb, EBML_ID_HEADER, 0);
651
    put_ebml_uint   (pb, EBML_ID_EBMLVERSION        ,           1);
652
    put_ebml_uint   (pb, EBML_ID_EBMLREADVERSION    ,           1);
653
    put_ebml_uint   (pb, EBML_ID_EBMLMAXIDLENGTH    ,           4);
654
    put_ebml_uint   (pb, EBML_ID_EBMLMAXSIZELENGTH  ,           8);
655
    put_ebml_string (pb, EBML_ID_DOCTYPE            ,  "matroska");
656
    put_ebml_uint   (pb, EBML_ID_DOCTYPEVERSION     ,           2);
657
    put_ebml_uint   (pb, EBML_ID_DOCTYPEREADVERSION ,           2);
658
    end_ebml_master(pb, ebml_header);
659

    
660
    mkv->segment = start_ebml_master(pb, MATROSKA_ID_SEGMENT, 0);
661
    mkv->segment_offset = url_ftell(pb);
662

    
663
    // we write 2 seek heads - one at the end of the file to point to each
664
    // cluster, and one at the beginning to point to all other level one
665
    // elements (including the seek head at the end of the file), which
666
    // isn't more than 10 elements if we only write one of each other
667
    // currently defined level 1 element
668
    mkv->main_seekhead    = mkv_start_seekhead(pb, mkv->segment_offset, 10);
669
    mkv->cluster_seekhead = mkv_start_seekhead(pb, mkv->segment_offset, 0);
670
    if (mkv->main_seekhead == NULL || mkv->cluster_seekhead == NULL)
671
        return AVERROR(ENOMEM);
672

    
673
    ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_INFO, url_ftell(pb));
674
    if (ret < 0) return ret;
675

    
676
    segment_info = start_ebml_master(pb, MATROSKA_ID_INFO, 0);
677
    put_ebml_uint(pb, MATROSKA_ID_TIMECODESCALE, 1000000);
678
    if (strlen(s->title))
679
        put_ebml_string(pb, MATROSKA_ID_TITLE, s->title);
680
    if (!(s->streams[0]->codec->flags & CODEC_FLAG_BITEXACT)) {
681
        put_ebml_string(pb, MATROSKA_ID_MUXINGAPP , LIBAVFORMAT_IDENT);
682
        put_ebml_string(pb, MATROSKA_ID_WRITINGAPP, LIBAVFORMAT_IDENT);
683

    
684
        // reserve space to write the segment UID later
685
        mkv->segment_uid = url_ftell(pb);
686
        put_ebml_void(pb, 19);
687
    }
688

    
689
    // reserve space for the duration
690
    mkv->duration = 0;
691
    mkv->duration_offset = url_ftell(pb);
692
    put_ebml_void(pb, 11);                  // assumes double-precision float to be written
693
    end_ebml_master(pb, segment_info);
694

    
695
    ret = mkv_write_tracks(s);
696
    if (ret < 0) return ret;
697

    
698
    ret = mkv_add_seekhead_entry(mkv->cluster_seekhead, MATROSKA_ID_CLUSTER, url_ftell(pb));
699
    if (ret < 0) return ret;
700

    
701
    mkv->cluster_pos = url_ftell(pb);
702
    mkv->cluster = start_ebml_master(pb, MATROSKA_ID_CLUSTER, 0);
703
    put_ebml_uint(pb, MATROSKA_ID_CLUSTERTIMECODE, 0);
704
    mkv->cluster_pts = 0;
705

    
706
    mkv->cues = mkv_start_cues(mkv->segment_offset);
707
    if (mkv->cues == NULL)
708
        return AVERROR(ENOMEM);
709

    
710
    return 0;
711
}
712

    
713
static int mkv_blockgroup_size(int pkt_size)
714
{
715
    int size = pkt_size + 4;
716
    size += ebml_num_size(size);
717
    size += 2;              // EBML ID for block and block duration
718
    size += 8;              // max size of block duration
719
    size += ebml_num_size(size);
720
    size += 1;              // blockgroup EBML ID
721
    return size;
722
}
723

    
724
static int ass_get_duration(const uint8_t *p)
725
{
726
    int sh, sm, ss, sc, eh, em, es, ec;
727
    uint64_t start, end;
728

    
729
    if (sscanf(p, "%*[^,],%d:%d:%d%*c%d,%d:%d:%d%*c%d",
730
               &sh, &sm, &ss, &sc, &eh, &em, &es, &ec) != 8)
731
        return 0;
732
    start = 3600000*sh + 60000*sm + 1000*ss + 10*sc;
733
    end   = 3600000*eh + 60000*em + 1000*es + 10*ec;
734
    return end - start;
735
}
736

    
737
static int mkv_write_ass_blocks(AVFormatContext *s, AVPacket *pkt)
738
{
739
    MatroskaMuxContext *mkv = s->priv_data;
740
    ByteIOContext *pb = s->pb;
741
    int i, layer = 0, max_duration = 0, size, line_size, data_size = pkt->size;
742
    uint8_t *start, *end, *data = pkt->data;
743
    ebml_master blockgroup;
744
    char buffer[2048];
745

    
746
    while (data_size) {
747
        int duration = ass_get_duration(data);
748
        max_duration = FFMAX(duration, max_duration);
749
        end = memchr(data, '\n', data_size);
750
        size = line_size = end ? end-data+1 : data_size;
751
        size -= end ? (end[-1]=='\r')+1 : 0;
752
        start = data;
753
        for (i=0; i<3; i++, start++)
754
            if (!(start = memchr(start, ',', size-(start-data))))
755
                return max_duration;
756
        size -= start - data;
757
        sscanf(data, "Dialogue: %d,", &layer);
758
        i = snprintf(buffer, sizeof(buffer), "%"PRId64",%d,",
759
                     s->streams[pkt->stream_index]->nb_frames++, layer);
760
        size = FFMIN(i+size, sizeof(buffer));
761
        memcpy(buffer+i, start, size-i);
762

    
763
        av_log(s, AV_LOG_DEBUG, "Writing block at offset %" PRIu64 ", size %d, "
764
               "pts %" PRId64 ", duration %d\n",
765
               url_ftell(pb), size, pkt->pts, duration);
766
        blockgroup = start_ebml_master(pb, MATROSKA_ID_BLOCKGROUP, mkv_blockgroup_size(size));
767
        put_ebml_id(pb, MATROSKA_ID_BLOCK);
768
        put_ebml_num(pb, size+4, 0);
769
        put_byte(pb, 0x80 | (pkt->stream_index + 1));     // this assumes stream_index is less than 126
770
        put_be16(pb, pkt->pts - mkv->cluster_pts);
771
        put_byte(pb, 0);
772
        put_buffer(pb, buffer, size);
773
        put_ebml_uint(pb, MATROSKA_ID_BLOCKDURATION, duration);
774
        end_ebml_master(pb, blockgroup);
775

    
776
        data += line_size;
777
        data_size -= line_size;
778
    }
779

    
780
    return max_duration;
781
}
782

    
783
static void mkv_write_block(AVFormatContext *s, unsigned int blockid, AVPacket *pkt, int flags)
784
{
785
    MatroskaMuxContext *mkv = s->priv_data;
786
    ByteIOContext *pb = s->pb;
787

    
788
    av_log(s, AV_LOG_DEBUG, "Writing block at offset %" PRIu64 ", size %d, "
789
           "pts %" PRId64 ", dts %" PRId64 ", duration %d, flags %d\n",
790
           url_ftell(pb), pkt->size, pkt->pts, pkt->dts, pkt->duration, flags);
791
    put_ebml_id(pb, blockid);
792
    put_ebml_num(pb, pkt->size+4, 0);
793
    put_byte(pb, 0x80 | (pkt->stream_index + 1));     // this assumes stream_index is less than 126
794
    put_be16(pb, pkt->pts - mkv->cluster_pts);
795
    put_byte(pb, flags);
796
    put_buffer(pb, pkt->data, pkt->size);
797
}
798

    
799
static int mkv_write_packet(AVFormatContext *s, AVPacket *pkt)
800
{
801
    MatroskaMuxContext *mkv = s->priv_data;
802
    ByteIOContext *pb = s->pb;
803
    AVCodecContext *codec = s->streams[pkt->stream_index]->codec;
804
    int keyframe = !!(pkt->flags & PKT_FLAG_KEY);
805
    int duration = pkt->duration;
806
    int ret;
807

    
808
    // start a new cluster every 5 MB or 5 sec
809
    if (url_ftell(pb) > mkv->cluster_pos + 5*1024*1024 || pkt->pts > mkv->cluster_pts + 5000) {
810
        av_log(s, AV_LOG_DEBUG, "Starting new cluster at offset %" PRIu64
811
               " bytes, pts %" PRIu64 "\n", url_ftell(pb), pkt->pts);
812
        end_ebml_master(pb, mkv->cluster);
813

    
814
        ret = mkv_add_seekhead_entry(mkv->cluster_seekhead, MATROSKA_ID_CLUSTER, url_ftell(pb));
815
        if (ret < 0) return ret;
816

    
817
        mkv->cluster_pos = url_ftell(pb);
818
        mkv->cluster = start_ebml_master(pb, MATROSKA_ID_CLUSTER, 0);
819
        put_ebml_uint(pb, MATROSKA_ID_CLUSTERTIMECODE, pkt->pts);
820
        mkv->cluster_pts = pkt->pts;
821
        av_md5_update(mkv->md5_ctx, pkt->data, FFMIN(200, pkt->size));
822
    }
823

    
824
    if (codec->codec_id == CODEC_ID_H264 &&
825
        codec->extradata_size > 0 && AV_RB32(codec->extradata) == 0x00000001) {
826
        /* from x264 or from bytestream h264 */
827
        /* nal reformating needed */
828
        int ret = ff_avc_parse_nal_units(pkt->data, &pkt->data, &pkt->size);
829
        if (ret < 0)
830
            return ret;
831
        assert(pkt->size);
832
    }
833

    
834
    if (codec->codec_type != CODEC_TYPE_SUBTITLE) {
835
        mkv_write_block(s, MATROSKA_ID_SIMPLEBLOCK, pkt, keyframe << 7);
836
    } else if (codec->codec_id == CODEC_ID_SSA) {
837
        duration = mkv_write_ass_blocks(s, pkt);
838
    } else {
839
        ebml_master blockgroup = start_ebml_master(pb, MATROSKA_ID_BLOCKGROUP, mkv_blockgroup_size(pkt->size));
840
        duration = pkt->convergence_duration;
841
        mkv_write_block(s, MATROSKA_ID_BLOCK, pkt, 0);
842
        put_ebml_uint(pb, MATROSKA_ID_BLOCKDURATION, duration);
843
        end_ebml_master(pb, blockgroup);
844
    }
845

    
846
    if (codec->codec_type == CODEC_TYPE_VIDEO && keyframe) {
847
        ret = mkv_add_cuepoint(mkv->cues, pkt, mkv->cluster_pos);
848
        if (ret < 0) return ret;
849
    }
850

    
851
    mkv->duration = FFMAX(mkv->duration, pkt->pts + duration);
852
    return 0;
853
}
854

    
855
static int mkv_write_trailer(AVFormatContext *s)
856
{
857
    MatroskaMuxContext *mkv = s->priv_data;
858
    ByteIOContext *pb = s->pb;
859
    int64_t currentpos, second_seekhead, cuespos;
860
    int ret;
861

    
862
    end_ebml_master(pb, mkv->cluster);
863

    
864
    if (!url_is_streamed(pb)) {
865
        cuespos = mkv_write_cues(pb, mkv->cues, s->nb_streams);
866
        second_seekhead = mkv_write_seekhead(pb, mkv->cluster_seekhead);
867

    
868
        ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_CUES    , cuespos);
869
        if (ret < 0) return ret;
870
        ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_SEEKHEAD, second_seekhead);
871
        if (ret < 0) return ret;
872
        mkv_write_seekhead(pb, mkv->main_seekhead);
873

    
874
        // update the duration
875
        av_log(s, AV_LOG_DEBUG, "end duration = %" PRIu64 "\n", mkv->duration);
876
        currentpos = url_ftell(pb);
877
        url_fseek(pb, mkv->duration_offset, SEEK_SET);
878
        put_ebml_float(pb, MATROSKA_ID_DURATION, mkv->duration);
879

    
880
        // write the md5sum of some frames as the segment UID
881
        if (!(s->streams[0]->codec->flags & CODEC_FLAG_BITEXACT)) {
882
            uint8_t segment_uid[16];
883
            av_md5_final(mkv->md5_ctx, segment_uid);
884
            url_fseek(pb, mkv->segment_uid, SEEK_SET);
885
            put_ebml_binary(pb, MATROSKA_ID_SEGMENTUID, segment_uid, 16);
886
        }
887
        url_fseek(pb, currentpos, SEEK_SET);
888
    }
889

    
890
    end_ebml_master(pb, mkv->segment);
891
    av_free(mkv->md5_ctx);
892
    return 0;
893
}
894

    
895
AVOutputFormat matroska_muxer = {
896
    "matroska",
897
    NULL_IF_CONFIG_SMALL("Matroska file format"),
898
    "video/x-matroska",
899
    "mkv",
900
    sizeof(MatroskaMuxContext),
901
    CODEC_ID_MP2,
902
    CODEC_ID_MPEG4,
903
    mkv_write_header,
904
    mkv_write_packet,
905
    mkv_write_trailer,
906
    .flags = AVFMT_GLOBALHEADER,
907
    .codec_tag = (const AVCodecTag* const []){codec_bmp_tags, codec_wav_tags, 0},
908
    .subtitle_codec = CODEC_ID_TEXT,
909
};
910

    
911
AVOutputFormat matroska_audio_muxer = {
912
    "matroska",
913
    NULL_IF_CONFIG_SMALL("Matroska file format"),
914
    "audio/x-matroska",
915
    "mka",
916
    sizeof(MatroskaMuxContext),
917
    CODEC_ID_MP2,
918
    CODEC_ID_NONE,
919
    mkv_write_header,
920
    mkv_write_packet,
921
    mkv_write_trailer,
922
    .flags = AVFMT_GLOBALHEADER,
923
    .codec_tag = (const AVCodecTag* const []){codec_wav_tags, 0},
924
};