1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
|
/*
* MPEG1/2 demuxer
* Copyright (c) 2000, 2001, 2002 Fabrice Bellard
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "avformat.h"
#include "internal.h"
#include "mpeg.h"
//#define DEBUG_SEEK
#undef NDEBUG
#include <assert.h>
/*********************************************/
/* demux code */
#define MAX_SYNC_SIZE 100000
static int check_pes(uint8_t *p, uint8_t *end){
int pes1;
int pes2= (p[3] & 0xC0) == 0x80
&& (p[4] & 0xC0) != 0x40
&&((p[4] & 0xC0) == 0x00 || (p[4]&0xC0)>>2 == (p[6]&0xF0));
for(p+=3; p<end && *p == 0xFF; p++);
if((*p&0xC0) == 0x40) p+=2;
if((*p&0xF0) == 0x20){
pes1= p[0]&p[2]&p[4]&1;
}else if((*p&0xF0) == 0x30){
pes1= p[0]&p[2]&p[4]&p[5]&p[7]&p[9]&1;
}else
pes1 = *p == 0x0F;
return pes1||pes2;
}
static int mpegps_probe(AVProbeData *p)
{
uint32_t code= -1;
int sys=0, pspack=0, priv1=0, vid=0, audio=0, invalid=0;
int i;
int score=0;
for(i=0; i<p->buf_size; i++){
code = (code<<8) + p->buf[i];
if ((code & 0xffffff00) == 0x100) {
int len= p->buf[i+1] << 8 | p->buf[i+2];
int pes= check_pes(p->buf+i, p->buf+p->buf_size);
if(code == SYSTEM_HEADER_START_CODE) sys++;
else if(code == PACK_START_CODE) pspack++;
else if((code & 0xf0) == VIDEO_ID && pes) vid++;
// skip pes payload to avoid start code emulation for private
// and audio streams
else if((code & 0xe0) == AUDIO_ID && pes) {audio++; i+=len;}
else if(code == PRIVATE_STREAM_1 && pes) {priv1++; i+=len;}
else if((code & 0xf0) == VIDEO_ID && !pes) invalid++;
else if((code & 0xe0) == AUDIO_ID && !pes) invalid++;
else if(code == PRIVATE_STREAM_1 && !pes) invalid++;
}
}
if(vid+audio > invalid) /* invalid VDR files nd short PES streams */
score= AVPROBE_SCORE_MAX/4;
//av_log(NULL, AV_LOG_ERROR, "%d %d %d %d %d %d len:%d\n", sys, priv1, pspack,vid, audio, invalid, p->buf_size);
if(sys>invalid && sys*9 <= pspack*10)
return pspack > 2 ? AVPROBE_SCORE_MAX/2+2 : AVPROBE_SCORE_MAX/4; // +1 for .mpg
if(pspack > invalid && (priv1+vid+audio)*10 >= pspack*9)
return pspack > 2 ? AVPROBE_SCORE_MAX/2+2 : AVPROBE_SCORE_MAX/4; // +1 for .mpg
if((!!vid ^ !!audio) && (audio > 4 || vid > 1) && !sys && !pspack && p->buf_size>2048 && vid + audio > invalid) /* PES stream */
return (audio > 12 || vid > 3) ? AVPROBE_SCORE_MAX/2+2 : AVPROBE_SCORE_MAX/4;
//02-Penguin.flac has sys:0 priv1:0 pspack:0 vid:0 audio:1
//mp3_misidentified_2.mp3 has sys:0 priv1:0 pspack:0 vid:0 audio:6
return score;
}
typedef struct MpegDemuxContext {
int32_t header_state;
unsigned char psm_es_type[256];
int sofdec;
} MpegDemuxContext;
static int mpegps_read_header(AVFormatContext *s,
AVFormatParameters *ap)
{
MpegDemuxContext *m = s->priv_data;
const char *sofdec = "Sofdec";
int v, i = 0;
m->header_state = 0xff;
s->ctx_flags |= AVFMTCTX_NOHEADER;
m->sofdec = -1;
do {
v = avio_r8(s->pb);
m->header_state = m->header_state << 8 | v;
m->sofdec++;
} while (v == sofdec[i] && i++ < 6);
m->sofdec = (m->sofdec == 6) ? 1 : 0;
/* no need to do more */
return 0;
}
static int64_t get_pts(AVIOContext *pb, int c)
{
uint8_t buf[5];
buf[0] = c<0 ? avio_r8(pb) : c;
avio_read(pb, buf+1, 4);
return ff_parse_pes_pts(buf);
}
static int find_next_start_code(AVIOContext *pb, int *size_ptr,
int32_t *header_state)
{
unsigned int state, v;
int val, n;
state = *header_state;
n = *size_ptr;
while (n > 0) {
if (url_feof(pb))
break;
v = avio_r8(pb);
n--;
if (state == 0x000001) {
state = ((state << 8) | v) & 0xffffff;
val = state;
goto found;
}
state = ((state << 8) | v) & 0xffffff;
}
val = -1;
found:
*header_state = state;
*size_ptr = n;
return val;
}
#if 0 /* unused, remove? */
/* XXX: optimize */
static int find_prev_start_code(AVIOContext *pb, int *size_ptr)
{
int64_t pos, pos_start;
int max_size, start_code;
max_size = *size_ptr;
pos_start = url_ftell(pb);
/* in order to go faster, we fill the buffer */
pos = pos_start - 16386;
if (pos < 0)
pos = 0;
url_fseek(pb, pos, SEEK_SET);
avio_r8(pb);
pos = pos_start;
for(;;) {
pos--;
if (pos < 0 || (pos_start - pos) >= max_size) {
start_code = -1;
goto the_end;
}
url_fseek(pb, pos, SEEK_SET);
start_code = avio_rb32(pb);
if ((start_code & 0xffffff00) == 0x100)
break;
}
the_end:
*size_ptr = pos_start - pos;
return start_code;
}
#endif
/**
* Extract stream types from a program stream map
* According to ISO/IEC 13818-1 ('MPEG-2 Systems') table 2-35
*
* @return number of bytes occupied by PSM in the bitstream
*/
static long mpegps_psm_parse(MpegDemuxContext *m, AVIOContext *pb)
{
int psm_length, ps_info_length, es_map_length;
psm_length = avio_rb16(pb);
avio_r8(pb);
avio_r8(pb);
ps_info_length = avio_rb16(pb);
/* skip program_stream_info */
url_fskip(pb, ps_info_length);
es_map_length = avio_rb16(pb);
/* at least one es available? */
while (es_map_length >= 4){
unsigned char type = avio_r8(pb);
unsigned char es_id = avio_r8(pb);
uint16_t es_info_length = avio_rb16(pb);
/* remember mapping from stream id to stream type */
m->psm_es_type[es_id] = type;
/* skip program_stream_info */
url_fskip(pb, es_info_length);
es_map_length -= 4 + es_info_length;
}
avio_rb32(pb); /* crc32 */
return 2 + psm_length;
}
/* read the next PES header. Return its position in ppos
(if not NULL), and its start code, pts and dts.
*/
static int mpegps_read_pes_header(AVFormatContext *s,
int64_t *ppos, int *pstart_code,
int64_t *ppts, int64_t *pdts)
{
MpegDemuxContext *m = s->priv_data;
int len, size, startcode, c, flags, header_len;
int pes_ext, ext2_len, id_ext, skip;
int64_t pts, dts;
int64_t last_sync= url_ftell(s->pb);
error_redo:
url_fseek(s->pb, last_sync, SEEK_SET);
redo:
/* next start code (should be immediately after) */
m->header_state = 0xff;
size = MAX_SYNC_SIZE;
startcode = find_next_start_code(s->pb, &size, &m->header_state);
last_sync = url_ftell(s->pb);
//printf("startcode=%x pos=0x%"PRIx64"\n", startcode, url_ftell(s->pb));
if (startcode < 0){
if(url_feof(s->pb))
return AVERROR_EOF;
//FIXME we should remember header_state
return AVERROR(EAGAIN);
}
if (startcode == PACK_START_CODE)
goto redo;
if (startcode == SYSTEM_HEADER_START_CODE)
goto redo;
if (startcode == PADDING_STREAM) {
url_fskip(s->pb, avio_rb16(s->pb));
goto redo;
}
if (startcode == PRIVATE_STREAM_2) {
len = avio_rb16(s->pb);
if (!m->sofdec) {
while (len-- >= 6) {
if (avio_r8(s->pb) == 'S') {
uint8_t buf[5];
avio_read(s->pb, buf, sizeof(buf));
m->sofdec = !memcmp(buf, "ofdec", 5);
len -= sizeof(buf);
break;
}
}
m->sofdec -= !m->sofdec;
}
url_fskip(s->pb, len);
goto redo;
}
if (startcode == PROGRAM_STREAM_MAP) {
mpegps_psm_parse(m, s->pb);
goto redo;
}
/* find matching stream */
if (!((startcode >= 0x1c0 && startcode <= 0x1df) ||
(startcode >= 0x1e0 && startcode <= 0x1ef) ||
(startcode == 0x1bd) || (startcode == 0x1fd)))
goto redo;
if (ppos) {
*ppos = url_ftell(s->pb) - 4;
}
len = avio_rb16(s->pb);
pts =
dts = AV_NOPTS_VALUE;
/* stuffing */
for(;;) {
if (len < 1)
goto error_redo;
c = avio_r8(s->pb);
len--;
/* XXX: for mpeg1, should test only bit 7 */
if (c != 0xff)
break;
}
if ((c & 0xc0) == 0x40) {
/* buffer scale & size */
avio_r8(s->pb);
c = avio_r8(s->pb);
len -= 2;
}
if ((c & 0xe0) == 0x20) {
dts = pts = get_pts(s->pb, c);
len -= 4;
if (c & 0x10){
dts = get_pts(s->pb, -1);
len -= 5;
}
} else if ((c & 0xc0) == 0x80) {
/* mpeg 2 PES */
#if 0 /* some streams have this field set for no apparent reason */
if ((c & 0x30) != 0) {
/* Encrypted multiplex not handled */
goto redo;
}
#endif
flags = avio_r8(s->pb);
header_len = avio_r8(s->pb);
len -= 2;
if (header_len > len)
goto error_redo;
len -= header_len;
if (flags & 0x80) {
dts = pts = get_pts(s->pb, -1);
header_len -= 5;
if (flags & 0x40) {
dts = get_pts(s->pb, -1);
header_len -= 5;
}
}
if (flags & 0x3f && header_len == 0){
flags &= 0xC0;
av_log(s, AV_LOG_WARNING, "Further flags set but no bytes left\n");
}
if (flags & 0x01) { /* PES extension */
pes_ext = avio_r8(s->pb);
header_len--;
/* Skip PES private data, program packet sequence counter and P-STD buffer */
skip = (pes_ext >> 4) & 0xb;
skip += skip & 0x9;
if (pes_ext & 0x40 || skip > header_len){
av_log(s, AV_LOG_WARNING, "pes_ext %X is invalid\n", pes_ext);
pes_ext=skip=0;
}
url_fskip(s->pb, skip);
header_len -= skip;
if (pes_ext & 0x01) { /* PES extension 2 */
ext2_len = avio_r8(s->pb);
header_len--;
if ((ext2_len & 0x7f) > 0) {
id_ext = avio_r8(s->pb);
if ((id_ext & 0x80) == 0)
startcode = ((startcode & 0xff) << 8) | id_ext;
header_len--;
}
}
}
if(header_len < 0)
goto error_redo;
url_fskip(s->pb, header_len);
}
else if( c!= 0xf )
goto redo;
if (startcode == PRIVATE_STREAM_1 && !m->psm_es_type[startcode & 0xff]) {
startcode = avio_r8(s->pb);
len--;
if (startcode >= 0x80 && startcode <= 0xcf) {
/* audio: skip header */
avio_r8(s->pb);
avio_r8(s->pb);
avio_r8(s->pb);
len -= 3;
if (startcode >= 0xb0 && startcode <= 0xbf) {
/* MLP/TrueHD audio has a 4-byte header */
avio_r8(s->pb);
len--;
}
}
}
if(len<0)
goto error_redo;
if(dts != AV_NOPTS_VALUE && ppos){
int i;
for(i=0; i<s->nb_streams; i++){
if(startcode == s->streams[i]->id &&
!url_is_streamed(s->pb) /* index useless on streams anyway */) {
ff_reduce_index(s, i);
av_add_index_entry(s->streams[i], *ppos, dts, 0, 0, AVINDEX_KEYFRAME /* FIXME keyframe? */);
}
}
}
*pstart_code = startcode;
*ppts = pts;
*pdts = dts;
return len;
}
static int mpegps_read_packet(AVFormatContext *s,
AVPacket *pkt)
{
MpegDemuxContext *m = s->priv_data;
AVStream *st;
int len, startcode, i, es_type;
enum CodecID codec_id = CODEC_ID_NONE;
enum AVMediaType type;
int64_t pts, dts, dummy_pos; //dummy_pos is needed for the index building to work
uint8_t av_uninit(dvdaudio_substream_type);
redo:
len = mpegps_read_pes_header(s, &dummy_pos, &startcode, &pts, &dts);
if (len < 0)
return len;
if(startcode == 0x1bd) {
dvdaudio_substream_type = avio_r8(s->pb);
url_fskip(s->pb, 3);
len -= 4;
}
/* now find stream */
for(i=0;i<s->nb_streams;i++) {
st = s->streams[i];
if (st->id == startcode)
goto found;
}
es_type = m->psm_es_type[startcode & 0xff];
if(es_type > 0 && es_type != STREAM_TYPE_PRIVATE_DATA){
if(es_type == STREAM_TYPE_VIDEO_MPEG1){
codec_id = CODEC_ID_MPEG2VIDEO;
type = AVMEDIA_TYPE_VIDEO;
} else if(es_type == STREAM_TYPE_VIDEO_MPEG2){
codec_id = CODEC_ID_MPEG2VIDEO;
type = AVMEDIA_TYPE_VIDEO;
} else if(es_type == STREAM_TYPE_AUDIO_MPEG1 ||
es_type == STREAM_TYPE_AUDIO_MPEG2){
codec_id = CODEC_ID_MP3;
type = AVMEDIA_TYPE_AUDIO;
} else if(es_type == STREAM_TYPE_AUDIO_AAC){
codec_id = CODEC_ID_AAC;
type = AVMEDIA_TYPE_AUDIO;
} else if(es_type == STREAM_TYPE_VIDEO_MPEG4){
codec_id = CODEC_ID_MPEG4;
type = AVMEDIA_TYPE_VIDEO;
} else if(es_type == STREAM_TYPE_VIDEO_H264){
codec_id = CODEC_ID_H264;
type = AVMEDIA_TYPE_VIDEO;
} else if(es_type == STREAM_TYPE_AUDIO_AC3){
codec_id = CODEC_ID_AC3;
type = AVMEDIA_TYPE_AUDIO;
} else {
goto skip;
}
} else if (startcode >= 0x1e0 && startcode <= 0x1ef) {
static const unsigned char avs_seqh[4] = { 0, 0, 1, 0xb0 };
unsigned char buf[8];
avio_read(s->pb, buf, 8);
url_fseek(s->pb, -8, SEEK_CUR);
if(!memcmp(buf, avs_seqh, 4) && (buf[6] != 0 || buf[7] != 1))
codec_id = CODEC_ID_CAVS;
else
codec_id = CODEC_ID_PROBE;
type = AVMEDIA_TYPE_VIDEO;
} else if (startcode >= 0x1c0 && startcode <= 0x1df) {
type = AVMEDIA_TYPE_AUDIO;
codec_id = m->sofdec > 0 ? CODEC_ID_ADPCM_ADX : CODEC_ID_MP2;
} else if (startcode >= 0x80 && startcode <= 0x87) {
type = AVMEDIA_TYPE_AUDIO;
codec_id = CODEC_ID_AC3;
} else if ( ( startcode >= 0x88 && startcode <= 0x8f)
||( startcode >= 0x98 && startcode <= 0x9f)) {
/* 0x90 - 0x97 is reserved for SDDS in DVD specs */
type = AVMEDIA_TYPE_AUDIO;
codec_id = CODEC_ID_DTS;
} else if (startcode >= 0xa0 && startcode <= 0xaf) {
type = AVMEDIA_TYPE_AUDIO;
/* 16 bit form will be handled as CODEC_ID_PCM_S16BE */
codec_id = CODEC_ID_PCM_DVD;
} else if (startcode >= 0xb0 && startcode <= 0xbf) {
type = AVMEDIA_TYPE_AUDIO;
codec_id = CODEC_ID_TRUEHD;
} else if (startcode >= 0xc0 && startcode <= 0xcf) {
/* Used for both AC-3 and E-AC-3 in EVOB files */
type = AVMEDIA_TYPE_AUDIO;
codec_id = CODEC_ID_AC3;
} else if (startcode >= 0x20 && startcode <= 0x3f) {
type = AVMEDIA_TYPE_SUBTITLE;
codec_id = CODEC_ID_DVD_SUBTITLE;
} else if (startcode >= 0xfd55 && startcode <= 0xfd5f) {
type = AVMEDIA_TYPE_VIDEO;
codec_id = CODEC_ID_VC1;
} else if (startcode == 0x1bd) {
// check dvd audio substream type
type = AVMEDIA_TYPE_AUDIO;
switch(dvdaudio_substream_type & 0xe0) {
case 0xa0: codec_id = CODEC_ID_PCM_DVD;
break;
case 0x80: if((dvdaudio_substream_type & 0xf8) == 0x88)
codec_id = CODEC_ID_DTS;
else codec_id = CODEC_ID_AC3;
break;
default: av_log(s, AV_LOG_ERROR, "Unknown 0x1bd sub-stream\n");
goto skip;
}
} else {
skip:
/* skip packet */
url_fskip(s->pb, len);
goto redo;
}
/* no stream found: add a new stream */
st = av_new_stream(s, startcode);
if (!st)
goto skip;
st->codec->codec_type = type;
st->codec->codec_id = codec_id;
if (codec_id != CODEC_ID_PCM_S16BE)
st->need_parsing = AVSTREAM_PARSE_FULL;
found:
if(st->discard >= AVDISCARD_ALL)
goto skip;
if ((startcode >= 0xa0 && startcode <= 0xaf) ||
(startcode == 0x1bd && ((dvdaudio_substream_type & 0xe0) == 0xa0))) {
int b1, freq;
/* for LPCM, we just skip the header and consider it is raw
audio data */
if (len <= 3)
goto skip;
avio_r8(s->pb); /* emphasis (1), muse(1), reserved(1), frame number(5) */
b1 = avio_r8(s->pb); /* quant (2), freq(2), reserved(1), channels(3) */
avio_r8(s->pb); /* dynamic range control (0x80 = off) */
len -= 3;
freq = (b1 >> 4) & 3;
st->codec->sample_rate = lpcm_freq_tab[freq];
st->codec->channels = 1 + (b1 & 7);
st->codec->bits_per_coded_sample = 16 + ((b1 >> 6) & 3) * 4;
st->codec->bit_rate = st->codec->channels *
st->codec->sample_rate *
st->codec->bits_per_coded_sample;
if (st->codec->bits_per_coded_sample == 16)
st->codec->codec_id = CODEC_ID_PCM_S16BE;
else if (st->codec->bits_per_coded_sample == 28)
return AVERROR(EINVAL);
}
av_new_packet(pkt, len);
avio_read(s->pb, pkt->data, pkt->size);
pkt->pts = pts;
pkt->dts = dts;
pkt->pos = dummy_pos;
pkt->stream_index = st->index;
#if 0
av_log(s, AV_LOG_DEBUG, "%d: pts=%0.3f dts=%0.3f size=%d\n",
pkt->stream_index, pkt->pts / 90000.0, pkt->dts / 90000.0, pkt->size);
#endif
return 0;
}
static int64_t mpegps_read_dts(AVFormatContext *s, int stream_index,
int64_t *ppos, int64_t pos_limit)
{
int len, startcode;
int64_t pos, pts, dts;
pos = *ppos;
#ifdef DEBUG_SEEK
printf("read_dts: pos=0x%"PRIx64" next=%d -> ", pos, find_next);
#endif
if (url_fseek(s->pb, pos, SEEK_SET) < 0)
return AV_NOPTS_VALUE;
for(;;) {
len = mpegps_read_pes_header(s, &pos, &startcode, &pts, &dts);
if (len < 0) {
#ifdef DEBUG_SEEK
printf("none (ret=%d)\n", len);
#endif
return AV_NOPTS_VALUE;
}
if (startcode == s->streams[stream_index]->id &&
dts != AV_NOPTS_VALUE) {
break;
}
url_fskip(s->pb, len);
}
#ifdef DEBUG_SEEK
printf("pos=0x%"PRIx64" dts=0x%"PRIx64" %0.3f\n", pos, dts, dts / 90000.0);
#endif
*ppos = pos;
return dts;
}
AVInputFormat ff_mpegps_demuxer = {
"mpeg",
NULL_IF_CONFIG_SMALL("MPEG-PS format"),
sizeof(MpegDemuxContext),
mpegps_probe,
mpegps_read_header,
mpegps_read_packet,
NULL,
NULL, //mpegps_read_seek,
mpegps_read_dts,
.flags = AVFMT_SHOW_IDS|AVFMT_TS_DISCONT,
};
|