aboutsummaryrefslogtreecommitdiffhomepage
path: root/demux_mov.c
blob: 2e61215517c6d3c8806e0c627fa66c35230be5ff (plain)
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
//  QuickTime MOV file parser by A'rpi
//  based on TOOLS/movinfo.c by me & Al3x
//  compressed header support from moov.c of the openquicktime lib.

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

#include "config.h"

#ifdef HAVE_PNG
// should be detected by ./configure...
#define HAVE_ZLIB
#endif

#include "mp_msg.h"
#include "help_mp.h"

#include "stream.h"
#include "demuxer.h"

#include "wine/mmreg.h"
#include "wine/avifmt.h"
#include "wine/vfw.h"

#include "codec-cfg.h"
#include "stheader.h"

#ifdef HAVE_ZLIB
#include <zlib.h>
#endif

typedef struct {
    unsigned int pts; // duration
    unsigned int size;
    off_t pos;
} mov_sample_t;

typedef struct {
    unsigned int sample; // number of the first sample in teh chunk
    unsigned int size;   // number of samples in the chunk
    int desc;            // for multiple codecs mode - not used
    off_t pos;
} mov_chunk_t;

typedef struct {
    unsigned int first;
    unsigned int spc;
    unsigned int sdid;
} mov_chunkmap_t;

typedef struct {
    unsigned int num;
    unsigned int dur;
} mov_durmap_t;

typedef struct {
    int id;
    int type;
    int pos;
    //
    int timescale;
    unsigned int length;
    int samplesize;  // 0 = variable
    int duration;    // 0 = variable
    int width,height; // for video
    unsigned int fourcc;
    //
    int tkdata_len;  // track data 
    unsigned char* tkdata;
    int stdata_len;  // stream data
    unsigned char* stdata;
    int samples_size;
    mov_sample_t* samples;
    int chunks_size;
    mov_chunk_t* chunks;
    int chunkmap_size;
    mov_chunkmap_t* chunkmap;
    int durmap_size;
    mov_durmap_t* durmap;
} mov_track_t;

void mov_build_index(mov_track_t* trak){
    int i,j,s;
    int last=trak->chunks_size;
    unsigned int pts=0;
    printf("MOV track: %d chunks, %d samples\n",trak->chunks_size,trak->samples_size);
    printf("pts=%d  scale=%d  time=%5.3f\n",trak->length,trak->timescale,(float)trak->length/(float)trak->timescale);
    // process chunkmap:
    i=trak->chunkmap_size;
    while(i>0){
	--i;
	for(j=trak->chunkmap[i].first;j<last;j++){
	    trak->chunks[j].desc=trak->chunkmap[i].sdid;
	    trak->chunks[j].size=trak->chunkmap[i].spc;
	}
	last=trak->chunkmap[i].first;
    }

    // calc pts of chunks:
    s=0;
    for(j=0;j<trak->chunks_size;j++){
        trak->chunks[j].sample=s;
        s+=trak->chunks[j].size;
    }

    if(!trak->samples_size){
	// constant sampesize
	if(trak->durmap_size==1 || (trak->durmap_size==2 && trak->durmap[1].num==1)){
	} else printf("*** constant samplesize & variable duration not yet supported! ***\nContact the author if you have such sample file!\n");
	return;
    }
    
    // calc pts:
    s=0;
    for(j=0;j<trak->durmap_size;j++){
	for(i=0;i<trak->durmap[j].num;i++){
	    trak->samples[s].pts=pts;
	    ++s;
	    pts+=trak->durmap[j].dur;
	}
    }
    
    // calc sample offsets
    s=0;
    for(j=0;j<trak->chunks_size;j++){
	off_t pos=trak->chunks[j].pos;
	for(i=0;i<trak->chunks[j].size;i++){
	    trak->samples[s].pos=pos;
#if 0
	    printf("Sample %5d: pts=%8d  off=0x%08X  size=%d\n",s,
		trak->samples[s].pts,
		(int)trak->samples[s].pos,
		trak->samples[s].size);
#endif
	    pos+=trak->samples[s].size;
	    ++s;
	}
    }

}

#define MOV_MAX_TRACKS 256

#define MOV_TRAK_UNKNOWN 0
#define MOV_TRAK_VIDEO 1
#define MOV_TRAK_AUDIO 2

typedef struct {
    off_t moov_start;
    off_t moov_end;
    off_t mdat_start;
    off_t mdat_end;
    int track_db;
    mov_track_t* tracks[MOV_MAX_TRACKS];
} mov_priv_t;

#define MOV_FOURCC(a,b,c,d) ((a<<24)|(b<<16)|(c<<8)|(d))

int mov_check_file(demuxer_t* demuxer){
    int flags=0;
    mov_priv_t* priv=malloc(sizeof(mov_priv_t));
    
    mp_msg(MSGT_DEMUX,MSGL_V,"Checking for MOV\n");
    
    memset(priv,0,sizeof(mov_priv_t));
    demuxer->priv=priv;
    
    while(1){
	off_t len=stream_read_dword(demuxer->stream);
	unsigned int id=stream_read_dword(demuxer->stream);
	if(stream_eof(demuxer->stream)) break; // EOF
	if(len<8) break; // invalid chunk
	switch(id){
	case MOV_FOURCC('m','o','o','v'):
	  mp_msg(MSGT_DEMUX,MSGL_V,"MOV: Movie header found!\n");
	  priv->moov_start=stream_tell(demuxer->stream);
	  priv->moov_end=priv->moov_start+len-8;
	  flags|=1;
	  break;
	case MOV_FOURCC('m','d','a','t'):
	  mp_msg(MSGT_DEMUX,MSGL_V,"MOV: Movie DATA found!\n");
	  priv->mdat_start=stream_tell(demuxer->stream);
	  priv->mdat_end=priv->mdat_start+len-8;
	  flags|=2;
	  break;
	default:
	  mp_msg(MSGT_DEMUX,MSGL_V,"MOV: unknown chunk: %.4s %d\n",&id,(int)len);
	}
	if(!stream_skip(demuxer->stream,len-8)) break;
    }
    
    if(flags==1)
	mp_msg(MSGT_DEMUX,MSGL_WARN,"MOV: missing data (mdat) chunk! Maybe broken file...\n");
    else if(flags==2)
	mp_msg(MSGT_DEMUX,MSGL_WARN,"MOV: missing header (moov/cmov) chunk! Maybe broken file...\n");

return (flags==3);
}

static void lschunks(demuxer_t* demuxer,int level,off_t endpos,mov_track_t* trak){
    mov_priv_t* priv=demuxer->priv;
    while(1){
	off_t pos;
	off_t len;
	unsigned int id;
	//
	pos=stream_tell(demuxer->stream);
//	printf("stream_tell==%d\n",pos);
	if(pos>=endpos) return; // END
	len=stream_read_dword(demuxer->stream);
//	printf("len==%d\n",len);
	if(len<8) return; // error
	len-=8;
	id=stream_read_dword(demuxer->stream);
	//
	mp_msg(MSGT_DEMUX,MSGL_DBG2,"lschunks %.4s  %d\n",&id,(int)len);
	//
	if(trak){
	  switch(id){
	    case MOV_FOURCC('t','k','h','d'): {
		mp_msg(MSGT_DEMUX,MSGL_V,"MOV: %*sTrack header!\n",level,"");
		// read codec data
		trak->tkdata_len=len;
		trak->tkdata=malloc(trak->tkdata_len);
		stream_read(demuxer->stream,trak->tkdata,trak->tkdata_len);
		break;
	    }
	    case MOV_FOURCC('m','d','h','d'): {
		unsigned int tmp;
		mp_msg(MSGT_DEMUX,MSGL_V,"MOV: %*sMedia header!\n",level,"");
#if 0
		tmp=stream_read_dword(demuxer->stream);
		printf("dword1: 0x%08X (%d)\n",tmp,tmp);
		tmp=stream_read_dword(demuxer->stream);
		printf("dword2: 0x%08X (%d)\n",tmp,tmp);
		tmp=stream_read_dword(demuxer->stream);
		printf("dword3: 0x%08X (%d)\n",tmp,tmp);
		tmp=stream_read_dword(demuxer->stream);
		printf("dword4: 0x%08X (%d)\n",tmp,tmp);
		tmp=stream_read_dword(demuxer->stream);
		printf("dword5: 0x%08X (%d)\n",tmp,tmp);
		tmp=stream_read_dword(demuxer->stream);
		printf("dword6: 0x%08X (%d)\n",tmp,tmp);
#endif
		stream_skip(demuxer->stream,12);
		// read timescale
		trak->timescale=stream_read_dword(demuxer->stream);
		// read length
		trak->length=stream_read_dword(demuxer->stream);
		break;
	    }
	    case MOV_FOURCC('v','m','h','d'): {
		mp_msg(MSGT_DEMUX,MSGL_V,"MOV: %*sVideo header!\n",level,"");
		trak->type=MOV_TRAK_VIDEO;
		// read video data
		break;
	    }
	    case MOV_FOURCC('s','m','h','d'): {
		mp_msg(MSGT_DEMUX,MSGL_V,"MOV: %*sSound header!\n",level,"");
		trak->type=MOV_TRAK_AUDIO;
		// read audio data
		break;
	    }
	    case MOV_FOURCC('s','t','s','d'): {
		int i=stream_read_dword(demuxer->stream); // temp!
		int count=stream_read_dword(demuxer->stream);
		mp_msg(MSGT_DEMUX,MSGL_V,"MOV: %*sDescription list! (cnt:%d)\n",level,"",count);
		for(i=0;i<count;i++){
		    off_t pos=stream_tell(demuxer->stream);
		    off_t len=stream_read_dword(demuxer->stream);
		    unsigned int fourcc=stream_read_dword_le(demuxer->stream);
		    if(len<8) break; // error
		    mp_msg(MSGT_DEMUX,MSGL_V,"MOV: %*s desc #%d: %.4s",level,"",i,&fourcc);
		    if(!i){
			trak->fourcc=fourcc;
			// read codec data
			trak->stdata_len=len-8;
			trak->stdata=malloc(trak->stdata_len);
			stream_read(demuxer->stream,trak->stdata,trak->stdata_len);
			if(trak->type==MOV_TRAK_VIDEO && trak->stdata_len>43){
			    mp_msg(MSGT_DEMUX,MSGL_V," '%.*s'",trak->stdata_len-43,trak->stdata+43);
			}
		    }
		    mp_msg(MSGT_DEMUX,MSGL_V,"\n");
		    if(fourcc!=trak->fourcc && i)
			mp_msg(MSGT_DEMUX,MSGL_WARN,MSGTR_MOVvariableFourCC);
		    if(!stream_seek(demuxer->stream,pos+len)) break;
		}
		break;
	    }
	    case MOV_FOURCC('s','t','t','s'): {
		int temp=stream_read_dword(demuxer->stream);
		int len=stream_read_dword(demuxer->stream);
		int i;
		int x=0;
		unsigned int pts=0;
		mp_msg(MSGT_DEMUX,MSGL_V,"MOV: %*sSample duration table! (%d blocks)\n",level,"",len);
		trak->durmap=malloc(sizeof(mov_durmap_t)*len);
		memset(trak->durmap,0,sizeof(mov_durmap_t)*len);
		trak->durmap_size=len;
		for(i=0;i<len;i++){
		    trak->durmap[i].num=stream_read_dword(demuxer->stream);
		    trak->durmap[i].dur=stream_read_dword(demuxer->stream);
		    pts+=trak->durmap[i].num*trak->durmap[i].dur;
		}
		if(trak->length!=pts) printf("Warning! pts=%d  length=%d\n",pts,trak->length);
		break;
	    }
	    case MOV_FOURCC('s','t','s','c'): {
		int temp=stream_read_dword(demuxer->stream);
		int len=stream_read_dword(demuxer->stream);
		int i;
		mp_msg(MSGT_DEMUX,MSGL_V,"MOV: %*sSample->Chunk mapping table!  (%d blocks)\n",level,"",len);
		// read data:
		trak->chunkmap_size=len;
		trak->chunkmap=malloc(sizeof(mov_chunkmap_t)*len);
		for(i=0;i<len;i++){
		    trak->chunkmap[i].first=stream_read_dword(demuxer->stream)-1;
		    trak->chunkmap[i].spc=stream_read_dword(demuxer->stream);
		    trak->chunkmap[i].sdid=stream_read_dword(demuxer->stream);
		}
		break;
	    }
	    case MOV_FOURCC('s','t','s','z'): {
		int temp=stream_read_dword(demuxer->stream);
		int ss=stream_read_dword(demuxer->stream);
		int len=stream_read_dword(demuxer->stream);
		mp_msg(MSGT_DEMUX,MSGL_V,"MOV: %*sSample size table!  len=%d  ss=%d\n",level,"",len,ss);
		trak->samplesize=ss;
		if(!ss){
		    // variable samplesize
		    int i;
		    trak->samples=realloc(trak->samples,sizeof(mov_sample_t)*len);
		    trak->samples_size=len;
		    for(i=0;i<len;i++)
			trak->samples[i].size=stream_read_dword(demuxer->stream);
		}
		break;
	    }
	    case MOV_FOURCC('s','t','c','o'): {
		int temp=stream_read_dword(demuxer->stream);
		int len=stream_read_dword(demuxer->stream);
		int i;
		mp_msg(MSGT_DEMUX,MSGL_V,"MOV: %*sChunk offset table! (%d chunks)\n",level,"",len);
		// extend array if needed:
		if(len>trak->chunks_size){
		    trak->chunks=realloc(trak->chunks,sizeof(mov_chunk_t)*len);
		    trak->chunks_size=len;
		}
		// read elements:
		for(i=0;i<len;i++) trak->chunks[i].pos=stream_read_dword(demuxer->stream);
		break;
	    }
	    case MOV_FOURCC('m','d','i','a'): {
		mp_msg(MSGT_DEMUX,MSGL_V,"MOV: %*sMedia stream!\n",level,"");
		lschunks(demuxer,level+1,pos+len,trak);
		break;
	    }
	    case MOV_FOURCC('m','i','n','f'): {
		mp_msg(MSGT_DEMUX,MSGL_V,"MOV: %*sMedia info!\n",level,"");
		lschunks(demuxer,level+1,pos+len,trak);
		break;
	    }
	    case MOV_FOURCC('s','t','b','l'): {
		mp_msg(MSGT_DEMUX,MSGL_V,"MOV: %*sSample info!\n",level,"");
		lschunks(demuxer,level+1,pos+len,trak);
		break;
	    }
	  }//switch(id)
	} else
	if(id==MOV_FOURCC('t','r','a','k')){
//	    if(trak) printf("MOV: Warning! trak in trak?\n");
	    if(priv->track_db>=MOV_MAX_TRACKS){
		mp_msg(MSGT_DEMUX,MSGL_WARN,MSGTR_MOVtooManyTrk);
		return;
	    }
	    trak=malloc(sizeof(mov_track_t));
	    memset(trak,0,sizeof(mov_track_t));
	    mp_msg(MSGT_DEMUX,MSGL_V,"MOV: Track #%d:\n",priv->track_db);
	    trak->id=priv->track_db;
	    priv->tracks[priv->track_db]=trak;
	    lschunks(demuxer,level+1,pos+len,trak);
	    mov_build_index(trak);
	    switch(trak->type){
	    case MOV_TRAK_AUDIO: {
		sh_audio_t* sh=new_sh_audio(demuxer,priv->track_db);
		sh->format=trak->fourcc;
		printf("!!! audio bits: %d  chans: %d\n",trak->stdata[19],trak->stdata[17]);
		printf("Fourcc: %.4s\n",&trak->fourcc);
		// Emulate WAVEFORMATEX struct:
		sh->wf=malloc(sizeof(WAVEFORMATEX));
		memset(sh->wf,0,sizeof(WAVEFORMATEX));
		sh->wf->nChannels=trak->stdata[17];
		sh->wf->wBitsPerSample=trak->stdata[19];
		sh->wf->nSamplesPerSec=trak->timescale;
		sh->wf->nAvgBytesPerSec=sh->wf->nChannels*((sh->wf->wBitsPerSample+7)/8)*sh->wf->nSamplesPerSec;
		// Selection:
		if(demuxer->audio->id==-1 || demuxer->audio->id==priv->track_db){
		    // (auto)selected audio track:
		    demuxer->audio->id=priv->track_db;
		    demuxer->audio->sh=sh; sh->ds=demuxer->audio;
		}
		break;
	    }
	    case MOV_TRAK_VIDEO: {
		sh_video_t* sh=new_sh_video(demuxer,priv->track_db);
		sh->format=trak->fourcc;
		sh->fps=trak->timescale;
		sh->frametime=1.0f/sh->fps;
		sh->disp_w=trak->tkdata[77]|(trak->tkdata[76]<<8);
		sh->disp_h=trak->tkdata[81]|(trak->tkdata[80]<<8);

		// emulate BITMAPINFOHEADER:
		sh->bih=malloc(sizeof(BITMAPINFOHEADER));
		memset(sh->bih,0,sizeof(BITMAPINFOHEADER));
		sh->bih->biSize=40;
		sh->bih->biWidth=sh->disp_w;
		sh->bih->biHeight=sh->disp_h;
		sh->bih->biPlanes=0;
		sh->bih->biBitCount=16;
		sh->bih->biCompression=trak->fourcc;
		sh->bih->biSizeImage=sh->bih->biWidth*sh->bih->biHeight;

		printf("Image size: %d x %d\n",sh->disp_w,sh->disp_h);
		printf("Fourcc: %.4s  Codec: '%.*s'\n",&trak->fourcc,trak->stdata_len-43,trak->stdata+43);
		
		if(demuxer->video->id==-1 || demuxer->video->id==priv->track_db){
		    // (auto)selected video track:
		    demuxer->video->id=priv->track_db;
		    demuxer->video->sh=sh; sh->ds=demuxer->video;
		}
		break;
	    }
	    }
	    printf("--------------\n");
	    priv->track_db++;
	    trak=NULL;
	} else
#ifndef HAVE_ZLIB
	if(id==MOV_FOURCC('c','m','o','v')){
	    mp_msg(MSGT_DEMUX,MSGL_ERR,MSGTR_MOVcomprhdr);
	    return;
	}
#else
	if(id==MOV_FOURCC('c','m','o','v')){
//	    mp_msg(MSGT_DEMUX,MSGL_ERR,MSGTR_MOVcomprhdr);
	    lschunks(demuxer,level+1,pos+len,NULL);
	} else
	if(id==MOV_FOURCC('d','c','o','m')){
//	    int temp=stream_read_dword(demuxer->stream);
	    unsigned int len=stream_read_dword(demuxer->stream);
	    printf("Compressed header uses %.4s algo!\n",&len);
	} else
	if(id==MOV_FOURCC('c','m','v','d')){
//	    int temp=stream_read_dword(demuxer->stream);
	    unsigned int moov_sz=stream_read_dword(demuxer->stream);
	    unsigned int cmov_sz=len-4;
	    unsigned char* cmov_buf=malloc(cmov_sz);
	    unsigned char* moov_buf=malloc(moov_sz+16);
	    int zret;
	    z_stream zstrm;
	    stream_t* backup;

	    printf("Compressed header size: %d / %d\n",cmov_sz,moov_sz);

	    stream_read(demuxer->stream,cmov_buf,cmov_sz);

	      zstrm.zalloc          = (alloc_func)0;
	      zstrm.zfree           = (free_func)0;
	      zstrm.opaque          = (voidpf)0;
	      zstrm.next_in         = cmov_buf;
	      zstrm.avail_in        = cmov_sz;
	      zstrm.next_out        = moov_buf;
	      zstrm.avail_out       = moov_sz;
	    
	      zret = inflateInit(&zstrm);
	      if (zret != Z_OK)
		{ fprintf(stderr,"QT cmov: inflateInit err %d\n",zret);
		return;
		}
	      zret = inflate(&zstrm, Z_NO_FLUSH);
	      if ((zret != Z_OK) && (zret != Z_STREAM_END))
		{ fprintf(stderr,"QT cmov inflate: ERR %d\n",zret);
		return;
		}
#if 0
	      else {
		FILE *DecOut;
		DecOut = fopen("Out.bin", "w");
		fwrite(moov_buf, 1, moov_sz, DecOut);
		fclose(DecOut);
	      }
#endif
	      if(moov_sz != zstrm.total_out) printf("Warning! moov size differs cmov: %d  zlib: %d\n",moov_sz,zstrm.total_out);
	      zret = inflateEnd(&zstrm);
	      
	      backup=demuxer->stream;
	       demuxer->stream=new_memory_stream(moov_buf,moov_sz);
	       stream_skip(demuxer->stream,8);
	       lschunks(demuxer,level+1,moov_sz,NULL); // parse uncompr. 'moov'
	       //free_stream(demuxer->stream);
	      demuxer->stream=backup;
	    
	}
#endif
	
	pos+=len+8;
	if(pos>=endpos) break;
	if(!stream_seek(demuxer->stream,pos)) break;
    }
}

int mov_read_header(demuxer_t* demuxer){
    mov_priv_t* priv=demuxer->priv;
    
    printf("mov_read_header!\n");

    // Parse header:    
    stream_reset(demuxer->stream);
    if(!stream_seek(demuxer->stream,priv->moov_start)) return 0; // ???
    lschunks(demuxer, 0, priv->moov_end, NULL);

#if 1    
    return 1;
#else
    mp_msg(MSGT_DEMUX,MSGL_ERR,MSGTR_MOVnotyetsupp);
    return 0;
#endif
}

// return value:
//     0 = EOF or no stream found
//     1 = successfully read a packet
int demux_mov_fill_buffer(demuxer_t *demuxer,demux_stream_t* ds){
    mov_priv_t* priv=demuxer->priv;
    mov_track_t* trak=NULL;
    float pts;
    
    if(ds->id<0 || ds->id>=priv->track_db) return 0;
    trak=priv->tracks[ds->id];

if(trak->samplesize){
    // read chunk:
    if(trak->pos>=trak->chunks_size) return 0; // EOF
    stream_seek(demuxer->stream,trak->chunks[trak->pos].pos);
    pts=(float)(trak->chunks[trak->pos].sample*trak->duration)/(float)trak->timescale;
    ds_read_packet(ds,demuxer->stream,trak->chunks[trak->pos].size*trak->samplesize,pts,trak->chunks[trak->pos].pos,0);
} else {
    // read sample:
    if(trak->pos>=trak->samples_size) return 0; // EOF
    stream_seek(demuxer->stream,trak->samples[trak->pos].pos);
    pts=(float)trak->samples[trak->pos].pts/(float)trak->timescale;
    ds_read_packet(ds,demuxer->stream,trak->samples[trak->pos].size,pts,trak->samples[trak->pos].pos,0);
}
    ++trak->pos;

    return 1;
    
}