vorbisfile.c 32.1 KB
Newer Older
Monty's avatar
 
Monty committed
1 2 3 4 5 6 7
/********************************************************************
 *                                                                  *
 * THIS FILE IS PART OF THE Ogg Vorbis SOFTWARE CODEC SOURCE CODE.  *
 * USE, DISTRIBUTION AND REPRODUCTION OF THIS SOURCE IS GOVERNED BY *
 * THE GNU PUBLIC LICENSE 2, WHICH IS INCLUDED WITH THIS SOURCE.    *
 * PLEASE READ THESE TERMS DISTRIBUTING.                            *
 *                                                                  *
Monty's avatar
 
Monty committed
8 9
 * THE OggSQUISH SOURCE CODE IS (C) COPYRIGHT 1994-2000             *
 * by Monty <monty@xiph.org> and The XIPHOPHORUS Company            *
Monty's avatar
 
Monty committed
10 11 12 13
 * http://www.xiph.org/                                             *
 *                                                                  *
 ********************************************************************

Monty's avatar
 
Monty committed
14
 function: stdio-based convenience library for opening/seeking/decoding
Monty's avatar
 
Monty committed
15
 last mod: $Id: vorbisfile.c,v 1.24 2000/06/14 10:13:35 xiphmont Exp $
Monty's avatar
 
Monty committed
16 17 18

 ********************************************************************/

Monty's avatar
 
Monty committed
19
#include <stdlib.h>
Monty's avatar
 
Monty committed
20
#include <stdio.h>
Monty's avatar
 
Monty committed
21
#include <string.h>
Monty's avatar
 
Monty committed
22
#include <math.h>
23 24
#include <assert.h>

Monty's avatar
 
Monty committed
25 26 27
#include "vorbis/codec.h"
#include "vorbis/vorbisfile.h"

Monty's avatar
 
Monty committed
28
#include "os.h"
Monty's avatar
 
Monty committed
29
#include "misc.h"
Monty's avatar
 
Monty committed
30 31 32 33 34 35 36

/* A 'chained bitstream' is a Vorbis bitstream that contains more than
   one logical bitstream arranged end to end (the only form of Ogg
   multiplexing allowed in a Vorbis bitstream; grouping [parallel
   multiplexing] is not allowed in Vorbis) */

/* A Vorbis file can be played beginning to end (streamed) without
Monty's avatar
 
Monty committed
37 38 39 40
   worrying ahead of time about chaining (see decoder_example.c).  If
   we have the whole file, however, and want random access
   (seeking/scrubbing) or desire to know the total length/time of a
   file, we need to account for the possibility of chaining. */
Monty's avatar
 
Monty committed
41 42

/* We can handle things a number of ways; we can determine the entire
Monty's avatar
 
Monty committed
43
   bitstream structure right off the bat, or find pieces on demand.
Monty's avatar
 
Monty committed
44
   This example determines and caches structure for the entire
Monty's avatar
 
Monty committed
45
   bitstream, but builds a virtual decoder on the fly when moving
Monty's avatar
 
Monty committed
46
   between links in the chain. */
Monty's avatar
 
Monty committed
47 48 49 50

/* There are also different ways to implement seeking.  Enough
   information exists in an Ogg bitstream to seek to
   sample-granularity positions in the output.  Or, one can seek by
Monty's avatar
 
Monty committed
51 52
   picking some portion of the stream roughly in the desired area if
   we only want course navigation through the stream. */
Monty's avatar
 
Monty committed
53

Monty's avatar
 
Monty committed
54 55 56 57 58 59 60 61 62
/*************************************************************************
 * Many, many internal helpers.  The intention is not to be confusing; 
 * rampant duplication and monolithic function implementation would be 
 * harder to understand anyway.  The high level functions are last.  Begin
 * grokking near the end of the file */

/* read a little more data from the file/pipe into the ogg_sync framer */
#define CHUNKSIZE 4096
static long _get_data(OggVorbis_File *vf){
Michael Smith's avatar
 
Michael Smith committed
63 64
  char *buffer=ogg_sync_buffer(&vf->oy,CHUNKSIZE);
  long bytes=(vf->callbacks.read_func)(buffer,1,CHUNKSIZE,vf->datasource);
Monty's avatar
 
Monty committed
65 66 67 68 69 70
  ogg_sync_wrote(&vf->oy,bytes);
  return(bytes);
}

/* save a tiny smidge of verbosity to make the code more readable */
static void _seek_helper(OggVorbis_File *vf,long offset){
Michael Smith's avatar
 
Michael Smith committed
71
  (vf->callbacks.seek_func)(vf->datasource, offset, SEEK_SET);
Monty's avatar
 
Monty committed
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
  vf->offset=offset;
  ogg_sync_reset(&vf->oy);
}

/* The read/seek functions track absolute position within the stream */

/* from the head of the stream, get the next page.  boundary specifies
   if the function is allowed to fetch more data from the stream (and
   how much) or only use internally buffered data.

   boundary: -1) unbounded search
              0) read no additional data; use cached only
	      n) search for a new page beginning for n bytes

   return:   -1) did not find a page 
              n) found a page at absolute offset n */

static long _get_next_page(OggVorbis_File *vf,ogg_page *og,int boundary){
  if(boundary>0)boundary+=vf->offset;
  while(1){
    long more;

    if(boundary>0 && vf->offset>=boundary)return(-1);
    more=ogg_sync_pageseek(&vf->oy,og);
    
    if(more<0){
      /* skipped n bytes */
      vf->offset-=more;
    }else{
      if(more==0){
	/* send more paramedics */
	if(!boundary)return(-1);
	if(_get_data(vf)<=0)return(-1);
      }else{
	/* got a page.  Return the offset at the page beginning,
           advance the internal offset past the page end */
	long ret=vf->offset;
	vf->offset+=more;
	return(ret);
	
      }
    }
  }
}

/* find the latest page beginning before the current stream cursor
   position. Much dirtier than the above as Ogg doesn't have any
   backward search linkage.  no 'readp' as it will certainly have to
   read. */
static long _get_prev_page(OggVorbis_File *vf,ogg_page *og){
  long begin=vf->offset;
  long ret;
  int offset=-1;

  while(offset==-1){
    begin-=CHUNKSIZE;
    _seek_helper(vf,begin);
    while(vf->offset<begin+CHUNKSIZE){
      ret=_get_next_page(vf,og,begin+CHUNKSIZE-vf->offset);
      if(ret==-1){
	break;
      }else{
	offset=ret;
      }
    }
  }

  /* we have the offset.  Actually snork and hold the page now */
  _seek_helper(vf,offset);
  ret=_get_next_page(vf,og,CHUNKSIZE);
  if(ret==-1){
    /* this shouldn't be possible */
    fprintf(stderr,"Missed page fencepost at end of logical bitstream. "
	    "Exiting.\n");
    exit(1);
  }
  return(offset);
}

/* finds each bitstream link one at a time using a bisection search
   (has to begin by knowing the offset of the lb's initial page).
   Recurses for each link so it can alloc the link storage after
   finding them all, then unroll and fill the cache at the same time */
static void _bisect_forward_serialno(OggVorbis_File *vf,
				     long begin,
				     long searched,
				     long end,
				     long currentno,
				     long m){
  long endsearched=end;
  long next=end;
  ogg_page og;
Monty's avatar
 
Monty committed
164
  long ret;
Monty's avatar
 
Monty committed
165
  
Monty's avatar
 
Monty committed
166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185
  /* the below guards against garbage seperating the last and
     first pages of two links. */
  while(searched<endsearched){
    long bisect;
    
    if(endsearched-searched<CHUNKSIZE){
      bisect=searched;
    }else{
      bisect=(searched+endsearched)/2;
    }
    
    _seek_helper(vf,bisect);
    ret=_get_next_page(vf,&og,-1);
    if(ret<0 || ogg_page_serialno(&og)!=currentno){
      endsearched=bisect;
      if(ret>=0)next=ret;
    }else{
      searched=ret+og.header_len+og.body_len;
    }
  }
Monty's avatar
 
Monty committed
186 187 188 189 190

  _seek_helper(vf,next);
  ret=_get_next_page(vf,&og,-1);
  
  if(searched>=end || ret==-1){
Monty's avatar
 
Monty committed
191
    vf->links=m+1;
Monty's avatar
 
Monty committed
192
    vf->offsets=malloc((m+2)*sizeof(int64_t));
Monty's avatar
 
Monty committed
193 194
    vf->offsets[m+1]=searched;
  }else{
Monty's avatar
 
Monty committed
195
    _bisect_forward_serialno(vf,next,vf->offset,
Monty's avatar
 
Monty committed
196 197 198 199 200
			     end,ogg_page_serialno(&og),m+1);
  }
  
  vf->offsets[m]=begin;
}
Monty's avatar
 
Monty committed
201

Monty's avatar
 
Monty committed
202 203
/* uses the local ogg_stream storage in vf; this is important for
   non-streaming input sources */
Monty's avatar
 
Monty committed
204 205
static int _fetch_headers(OggVorbis_File *vf,vorbis_info *vi,vorbis_comment *vc,
			  long *serialno){
Monty's avatar
 
Monty committed
206 207 208
  ogg_page og;
  ogg_packet op;
  int i,ret;
Monty's avatar
 
Monty committed
209

Monty's avatar
 
Monty committed
210 211 212 213 214 215 216 217 218 219 220 221 222
  ret=_get_next_page(vf,&og,CHUNKSIZE);
  if(ret==-1){
    fprintf(stderr,"Did not find initial header for bitstream.\n");
    return -1;
  }
  
  if(serialno)*serialno=ogg_page_serialno(&og);
  ogg_stream_init(&vf->os,ogg_page_serialno(&og));
  
  /* extract the initial header from the first page and verify that the
     Ogg bitstream is in fact Vorbis data */
  
  vorbis_info_init(vi);
Monty's avatar
 
Monty committed
223
  vorbis_comment_init(vc);
Monty's avatar
 
Monty committed
224 225 226 227 228 229 230 231
  
  i=0;
  while(i<3){
    ogg_stream_pagein(&vf->os,&og);
    while(i<3){
      int result=ogg_stream_packetout(&vf->os,&op);
      if(result==0)break;
      if(result==-1){
Monty's avatar
 
Monty committed
232
	fprintf(stderr,"Corrupt header in logical bitstream.\n");
Monty's avatar
 
Monty committed
233 234
	goto bail_header;
      }
Monty's avatar
 
Monty committed
235
      if(vorbis_synthesis_headerin(vi,vc,&op)){
Monty's avatar
 
Monty committed
236
	fprintf(stderr,"Illegal header in logical bitstream.\n");
Monty's avatar
 
Monty committed
237 238 239 240 241 242
	goto bail_header;
      }
      i++;
    }
    if(i<3)
      if(_get_next_page(vf,&og,1)<0){
Monty's avatar
 
Monty committed
243
	fprintf(stderr,"Missing header in logical bitstream.\n");
Monty's avatar
 
Monty committed
244 245 246 247
	goto bail_header;
      }
  }
  return 0; 
Monty's avatar
 
Monty committed
248

Monty's avatar
 
Monty committed
249 250
 bail_header:
  vorbis_info_clear(vi);
Monty's avatar
 
Monty committed
251
  vorbis_comment_clear(vc);
Monty's avatar
 
Monty committed
252 253 254
  ogg_stream_clear(&vf->os);
  return -1;
}
Monty's avatar
 
Monty committed
255

Monty's avatar
 
Monty committed
256 257 258 259
/* last step of the OggVorbis_File initialization; get all the
   vorbis_info structs and PCM positions.  Only called by the seekable
   initialization (local stream storage is hacked slightly; pay
   attention to how that's done) */
Monty's avatar
 
Monty committed
260 261
static void _prefetch_all_headers(OggVorbis_File *vf,vorbis_info *first_i,
				  vorbis_comment *first_c,
Monty's avatar
 
Monty committed
262
				  long dataoffset){
Monty's avatar
 
Monty committed
263 264 265
  ogg_page og;
  int i,ret;
  
Monty's avatar
 
Monty committed
266
  vf->vi=calloc(vf->links,sizeof(vorbis_info));
Monty's avatar
 
Monty committed
267
  vf->vc=calloc(vf->links,sizeof(vorbis_info));
Monty's avatar
 
Monty committed
268
  vf->dataoffsets=malloc(vf->links*sizeof(int64_t));
Monty's avatar
 
Monty committed
269
  vf->pcmlengths=malloc(vf->links*sizeof(int64_t));
Monty's avatar
 
Monty committed
270 271 272
  vf->serialnos=malloc(vf->links*sizeof(long));
  
  for(i=0;i<vf->links;i++){
Monty's avatar
 
Monty committed
273
    if(first_i && first_c && i==0){
Monty's avatar
 
Monty committed
274 275
      /* we already grabbed the initial header earlier.  This just
         saves the waste of grabbing it again */
Monty's avatar
 
Monty committed
276 277
      memcpy(vf->vi+i,first_i,sizeof(vorbis_info));
      memcpy(vf->vc+i,first_c,sizeof(vorbis_comment));
Monty's avatar
 
Monty committed
278
      vf->dataoffsets[i]=dataoffset;
Monty's avatar
 
Monty committed
279
    }else{
Monty's avatar
 
Monty committed
280

Monty's avatar
 
Monty committed
281
      /* seek to the location of the initial header */
Monty's avatar
 
Monty committed
282

Monty's avatar
 
Monty committed
283
      _seek_helper(vf,vf->offsets[i]);
Monty's avatar
 
Monty committed
284
      if(_fetch_headers(vf,vf->vi+i,vf->vc+i,NULL)==-1){
Monty's avatar
 
Monty committed
285
	fprintf(stderr,"Error opening logical bitstream #%d.\n\n",i+1);
Monty's avatar
 
Monty committed
286 287
    	vf->dataoffsets[i]=-1;
      }else{
Monty's avatar
 
Monty committed
288
	vf->dataoffsets[i]=vf->offset;
Monty's avatar
 
Monty committed
289 290
        ogg_stream_clear(&vf->os);
      }
Monty's avatar
 
Monty committed
291
    }
Monty's avatar
 
Monty committed
292

Monty's avatar
 
Monty committed
293 294 295 296 297
    /* get the serial number and PCM length of this link. To do this,
       get the last page of the stream */
    {
      long end=vf->offsets[i+1];
      _seek_helper(vf,end);
Monty's avatar
 
Monty committed
298

Monty's avatar
 
Monty committed
299 300 301 302 303 304 305
      while(1){
	ret=_get_prev_page(vf,&og);
	if(ret==-1){
	  /* this should not be possible */
	  fprintf(stderr,"Could not find last page of logical "
		  "bitstream #%d\n\n",i);
	  vorbis_info_clear(vf->vi+i);
Monty's avatar
 
Monty committed
306
	  vorbis_comment_clear(vf->vc+i);
Monty's avatar
 
Monty committed
307 308 309 310 311 312 313 314 315 316
	  break;
	}
	if(ogg_page_frameno(&og)!=-1){
	  vf->serialnos[i]=ogg_page_serialno(&og);
	  vf->pcmlengths[i]=ogg_page_frameno(&og);
	  break;
	}
      }
    }
  }
Monty's avatar
 
Monty committed
317 318
}

Monty's avatar
 
Monty committed
319 320 321 322 323 324 325 326
static int _make_decode_ready(OggVorbis_File *vf){
  if(vf->decode_ready)exit(1);
  vorbis_synthesis_init(&vf->vd,vf->vi);
  vorbis_block_init(&vf->vd,&vf->vb);
  vf->decode_ready=1;
  return(0);
}

Monty's avatar
 
Monty committed
327
static int _open_seekable(OggVorbis_File *vf){
Monty's avatar
 
Monty committed
328 329
  vorbis_info initial_i;
  vorbis_comment initial_c;
Monty's avatar
 
Monty committed
330 331
  long serialno,end;
  int ret;
Monty's avatar
 
Monty committed
332
  long dataoffset;
Monty's avatar
 
Monty committed
333 334 335
  ogg_page og;
  
  /* is this even vorbis...? */
Monty's avatar
 
Monty committed
336
  ret=_fetch_headers(vf,&initial_i,&initial_c,&serialno);
Monty's avatar
 
Monty committed
337
  dataoffset=vf->offset;
Monty's avatar
 
Monty committed
338 339 340 341 342
  ogg_stream_clear(&vf->os);
  if(ret==-1)return(-1);
  
  /* we can seek, so set out learning all about this file */
  vf->seekable=1;
Michael Smith's avatar
 
Michael Smith committed
343 344
  (vf->callbacks.seek_func)(vf->datasource,0,SEEK_END);
  vf->offset=vf->end=(vf->callbacks.tell_func)(vf->datasource);
Monty's avatar
 
Monty committed
345 346 347 348
  
  /* We get the offset for the last page of the physical bitstream.
     Most OggVorbis files will contain a single logical bitstream */
  end=_get_prev_page(vf,&og);
Monty's avatar
 
Monty committed
349

Monty's avatar
 
Monty committed
350 351
  /* moer than one logical bitstream? */
  if(ogg_page_serialno(&og)!=serialno){
Monty's avatar
 
Monty committed
352

Monty's avatar
 
Monty committed
353 354 355
    /* Chained bitstream. Bisect-search each logical bitstream
       section.  Do so based on serial number only */
    _bisect_forward_serialno(vf,0,0,end+1,serialno,0);
Monty's avatar
 
Monty committed
356

Monty's avatar
 
Monty committed
357 358 359 360 361 362 363
  }else{

    /* Only one logical bitstream */
    _bisect_forward_serialno(vf,0,end,end+1,serialno,0);

  }

Monty's avatar
 
Monty committed
364
  _prefetch_all_headers(vf,&initial_i,&initial_c,dataoffset);
Monty's avatar
 
Monty committed
365
  ov_raw_seek(vf,0);
Monty's avatar
 
Monty committed
366 367 368 369 370 371 372

  return(0);
}

static int _open_nonseekable(OggVorbis_File *vf){
  /* we cannot seek. Set up a 'single' (current) logical bitstream entry  */
  vf->links=1;
373 374
  vf->vi=calloc(vf->links,sizeof(vorbis_info));
  vf->vc=calloc(vf->links,sizeof(vorbis_info));
Monty's avatar
 
Monty committed
375 376

  /* Try to fetch the headers, maintaining all the storage */
Monty's avatar
 
Monty committed
377
  if(_fetch_headers(vf,vf->vi,vf->vc,&vf->current_serialno)==-1)return(-1);
Monty's avatar
 
Monty committed
378 379
  _make_decode_ready(vf);

Monty's avatar
 
Monty committed
380 381
  return 0;
}
Monty's avatar
 
Monty committed
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

/* clear out the current logical bitstream decoder */ 
static void _decode_clear(OggVorbis_File *vf){
  ogg_stream_clear(&vf->os);
  vorbis_dsp_clear(&vf->vd);
  vorbis_block_clear(&vf->vb);
  vf->pcm_offset=-1;
  vf->decode_ready=0;
}

/* fetch and process a packet.  Handles the case where we're at a
   bitstream boundary and dumps the decoding machine.  If the decoding
   machine is unloaded, it loads it.  It also keeps pcm_offset up to
   date (seek and read both use this.  seek uses a special hack with
   readp). 

   return: -1) hole in the data (lost packet) 
            0) need more date (only if readp==0)/eof
	    1) got a packet 
*/

static int _process_packet(OggVorbis_File *vf,int readp){
  ogg_page og;

  /* handle one packet.  Try to fetch it from current stream state */
  /* extract packets from page */
  while(1){
    
    /* process a packet if we can.  If the machine isn't loaded,
       neither is a page */
    if(vf->decode_ready){
      ogg_packet op;
      int result=ogg_stream_packetout(&vf->os,&op);
Monty's avatar
 
Monty committed
415
      int64_t frameno;
Monty's avatar
 
Monty committed
416 417 418 419 420
      
      if(result==-1)return(-1); /* hole in the data. alert the toplevel */
      if(result>0){
	/* got a packet.  process it */
	frameno=op.frameno;
Monty's avatar
 
Monty committed
421 422 423 424 425 426 427 428
	if(!vorbis_synthesis(&vf->vb,&op)){ /* lazy check for lazy
                                               header handling.  The
                                               header packets aren't
                                               audio, so if/when we
                                               submit them,
                                               vorbis_synthesis will
                                               reject them */
	  vorbis_synthesis_blockin(&vf->vd,&vf->vb);
Monty's avatar
 
Monty committed
429
	  
Monty's avatar
 
Monty committed
430
	  /* update the pcm offset. */
Monty's avatar
 
Monty committed
431
	  if(frameno!=-1 && !op.e_o_s){
Monty's avatar
 
Monty committed
432 433 434 435 436 437 438
	    int link=(vf->seekable?vf->current_link:0);
	    double **dummy;
	    int i,samples;
	    
	    /* this packet has a pcm_offset on it (the last packet
	       completed on a page carries the offset) After processing
	       (above), we know the pcm position of the *last* sample
Monty's avatar
 
Monty committed
439 440 441 442 443 444 445 446 447
	       ready to be returned. Find the offset of the *first*

	       As an aside, this trick is inaccurate if we begin
	       reading anew right at the last page; the end-of-stream
	       frameno declares the last frame in the stream, and the
	       last packet of the last page may be a partial frame.
	       So, we need a previous frameno from an in-sequence page
	       to have a reference point.  Thus the !op.e_o_s clause
	       above */
Monty's avatar
 
Monty committed
448 449 450 451 452 453 454 455 456
	    
	    samples=vorbis_synthesis_pcmout(&vf->vd,&dummy);
	    
	    frameno-=samples;
	    for(i=0;i<link;i++)
	      frameno+=vf->pcmlengths[i];
	    vf->pcm_offset=frameno;
	  }
	  return(1);
Monty's avatar
 
Monty committed
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
	}
      }
    }

    if(!readp)return(0);
    if(_get_next_page(vf,&og,-1)<0)return(0); /* eof. leave unitialized */

    /* has our decoding just traversed a bitstream boundary? */
    if(vf->decode_ready){
      if(vf->current_serialno!=ogg_page_serialno(&og)){
	_decode_clear(vf);
      }
    }

    /* Do we need to load a new machine before submitting the page? */
    /* This is different in the seekable and non-seekable cases.  

       In the seekable case, we already have all the header
       information loaded and cached; we just initialize the machine
       with it and continue on our merry way.

       In the non-seekable (streaming) case, we'll only be at a
       boundary if we just left the previous logical bitstream and
       we're now nominally at the header of the next bitstream
    */

    if(!vf->decode_ready){
      int link;
      if(vf->seekable){
	vf->current_serialno=ogg_page_serialno(&og);
	
	/* match the serialno to bitstream section.  We use this rather than
	   offset positions to avoid problems near logical bitstream
	   boundaries */
	for(link=0;link<vf->links;link++)
	  if(vf->serialnos[link]==vf->current_serialno)break;
	if(link==vf->links)return(-1); /* sign of a bogus stream.  error out,
					  leave machine uninitialized */
	
	vf->current_link=link;
Monty's avatar
 
Monty committed
497 498

	ogg_stream_init(&vf->os,vf->current_serialno);
Monty's avatar
 
Monty committed
499
	ogg_stream_reset(&vf->os); 
Monty's avatar
 
Monty committed
500

Monty's avatar
 
Monty committed
501 502 503 504
      }else{
	/* we're streaming */
	/* fetch the three header packets, build the info struct */
	
Monty's avatar
 
Monty committed
505
	_fetch_headers(vf,vf->vi,vf->vc,&vf->current_serialno);
Monty's avatar
 
Monty committed
506 507 508 509
	vf->current_link++;
	link=0;
      }
      
Monty's avatar
 
Monty committed
510
      _make_decode_ready(vf);
Monty's avatar
 
Monty committed
511 512 513 514 515
    }
    ogg_stream_pagein(&vf->os,&og);
  }
}

Monty's avatar
 
Monty committed
516 517 518 519 520 521 522 523 524 525 526 527
/**********************************************************************
 * The helpers are over; it's all toplevel interface from here on out */
 
/* clear out the OggVorbis_File struct */
int ov_clear(OggVorbis_File *vf){
  if(vf){
    vorbis_block_clear(&vf->vb);
    vorbis_dsp_clear(&vf->vd);
    ogg_stream_clear(&vf->os);
    
    if(vf->vi && vf->links){
      int i;
Monty's avatar
 
Monty committed
528
      for(i=0;i<vf->links;i++){
Monty's avatar
 
Monty committed
529
	vorbis_info_clear(vf->vi+i);
Monty's avatar
 
Monty committed
530 531
	vorbis_comment_clear(vf->vc+i);
      }
Monty's avatar
 
Monty committed
532
      free(vf->vi);
Monty's avatar
 
Monty committed
533
      free(vf->vc);
Monty's avatar
 
Monty committed
534
    }
Monty's avatar
 
Monty committed
535
    if(vf->dataoffsets)free(vf->dataoffsets);
Monty's avatar
 
Monty committed
536 537 538 539
    if(vf->pcmlengths)free(vf->pcmlengths);
    if(vf->serialnos)free(vf->serialnos);
    if(vf->offsets)free(vf->offsets);
    ogg_sync_clear(&vf->oy);
Michael Smith's avatar
 
Michael Smith committed
540
    if(vf->datasource)(vf->callbacks.close_func)(vf->datasource);
Monty's avatar
 
Monty committed
541 542
    memset(vf,0,sizeof(OggVorbis_File));
  }
Monty's avatar
 
Monty committed
543
#ifdef DEBUG_LEAKS
Monty's avatar
 
Monty committed
544
  _VDBG_dump();
Monty's avatar
 
Monty committed
545
#endif
Monty's avatar
 
Monty committed
546
  return(0);
Monty's avatar
 
Monty committed
547
}
Monty's avatar
 
Monty committed
548

Monty's avatar
 
Monty committed
549 550 551 552
static int _fseek64_wrap(FILE *f,int64_t off,int whence){
  return fseek(f,(int)off,whence);
}

Monty's avatar
 
Monty committed
553 554
/* inspects the OggVorbis file and finds/documents all the logical
   bitstreams contained in it.  Tries to be tolerant of logical
Monty's avatar
 
Monty committed
555 556 557 558 559 560
   bitstream sections that are truncated/woogie. 

   return: -1) error
            0) OK
*/

Monty's avatar
 
Monty committed
561
int ov_open(FILE *f,OggVorbis_File *vf,char *initial,long ibytes){
Michael Smith's avatar
 
Michael Smith committed
562
  ov_callbacks callbacks = {
Michael Smith's avatar
 
Michael Smith committed
563
    (size_t (*)(void *, size_t, size_t, void *))  fread,
Monty's avatar
 
Monty committed
564
    (int (*)(void *, int64_t, int))              _fseek64_wrap,
Michael Smith's avatar
 
Michael Smith committed
565 566 567
    (int (*)(void *))                             fclose,
    (long (*)(void *))                            ftell
  };
Michael Smith's avatar
 
Michael Smith committed
568 569 570 571 572 573 574 575 576

  return ov_open_callbacks((void *)f, vf, initial, ibytes, callbacks);
}
  

int ov_open_callbacks(void *f,OggVorbis_File *vf,char *initial,long ibytes,
    ov_callbacks callbacks)
{
  long offset=callbacks.seek_func(f,0,SEEK_CUR);
Monty's avatar
 
Monty committed
577 578 579
  int ret;

  memset(vf,0,sizeof(OggVorbis_File));
Michael Smith's avatar
 
Michael Smith committed
580 581
  vf->datasource=f;
  vf->callbacks = callbacks;
Monty's avatar
 
Monty committed
582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602

  /* init the framing state */
  ogg_sync_init(&vf->oy);

  /* perhaps some data was previously read into a buffer for testing
     against other stream types.  Allow initialization from this
     previously read data (as we may be reading from a non-seekable
     stream) */
  if(initial){
    char *buffer=ogg_sync_buffer(&vf->oy,ibytes);
    memcpy(buffer,initial,ibytes);
    ogg_sync_wrote(&vf->oy,ibytes);
  }

  /* can we seek? Stevens suggests the seek test was portable */
  if(offset!=-1){
    ret=_open_seekable(vf);
  }else{
    ret=_open_nonseekable(vf);
  }
  if(ret){
Michael Smith's avatar
 
Michael Smith committed
603
    vf->datasource=NULL;
Monty's avatar
 
Monty committed
604 605 606 607 608
    ov_clear(vf);
  }
  return(ret);
}

Monty's avatar
 
Monty committed
609
/* How many logical bitstreams in this physical bitstream? */
Monty's avatar
 
Monty committed
610 611
long ov_streams(OggVorbis_File *vf){
  return vf->links;
Monty's avatar
 
Monty committed
612 613
}

Monty's avatar
 
Monty committed
614
/* Is the FILE * associated with vf seekable? */
Monty's avatar
 
Monty committed
615 616
long ov_seekable(OggVorbis_File *vf){
  return vf->seekable;
Monty's avatar
 
Monty committed
617 618
}

Monty's avatar
 
Monty committed
619 620 621 622 623 624 625 626 627 628 629
/* returns the bitrate for a given logical bitstream or the entire
   physical bitstream.  If the file is open for random access, it will
   find the *actual* average bitrate.  If the file is streaming, it
   returns the nominal bitrate (if set) else the average of the
   upper/lower bounds (if set) else -1 (unset).

   If you want the actual bitrate field settings, get them from the
   vorbis_info structs */

long ov_bitrate(OggVorbis_File *vf,int i){
  if(i>=vf->links)return(-1);
Monty's avatar
 
Monty committed
630
  if(!vf->seekable && i!=0)return(ov_bitrate(vf,0));
Monty's avatar
 
Monty committed
631
  if(i<0){
Monty's avatar
 
Monty committed
632
    int64_t bits=0;
Monty's avatar
 
Monty committed
633 634
    int i;
    for(i=0;i<vf->links;i++)
Monty's avatar
 
Monty committed
635
      bits+=(vf->offsets[i+1]-vf->dataoffsets[i])*8;
Monty's avatar
 
Monty committed
636 637 638 639
    return(rint(bits/ov_time_total(vf,-1)));
  }else{
    if(vf->seekable){
      /* return the actual bitrate */
Monty's avatar
 
Monty committed
640
      return(rint((vf->offsets[i+1]-vf->dataoffsets[i])*8/ov_time_total(vf,i)));
Monty's avatar
 
Monty committed
641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669
    }else{
      /* return nominal if set */
      if(vf->vi[i].bitrate_nominal>0){
	return vf->vi[i].bitrate_nominal;
      }else{
	if(vf->vi[i].bitrate_upper>0){
	  if(vf->vi[i].bitrate_lower>0){
	    return (vf->vi[i].bitrate_upper+vf->vi[i].bitrate_lower)/2;
	  }else{
	    return vf->vi[i].bitrate_upper;
	  }
	}
	return(-1);
      }
    }
  }
}

/* Guess */
long ov_serialnumber(OggVorbis_File *vf,int i){
  if(i>=vf->links)return(-1);
  if(!vf->seekable && i>=0)return(ov_serialnumber(vf,-1));
  if(i<0){
    return(vf->current_serialno);
  }else{
    return(vf->serialnos[i]);
  }
}

Monty's avatar
 
Monty committed
670 671 672 673
/* returns: total raw (compressed) length of content if i==-1
            raw (compressed) length of that logical bitstream for i==0 to n
	    -1 if the stream is not seekable (we can't know the length)
*/
Monty's avatar
 
Monty committed
674
int64_t ov_raw_total(OggVorbis_File *vf,int i){
Monty's avatar
 
Monty committed
675 676
  if(!vf->seekable || i>=vf->links)return(-1);
  if(i<0){
Monty's avatar
 
Monty committed
677 678 679 680 681 682 683 684 685
    long acc=0;
    int i;
    for(i=0;i<vf->links;i++)
      acc+=ov_raw_total(vf,i);
    return(acc);
  }else{
    return(vf->offsets[i+1]-vf->offsets[i]);
  }
}
Monty's avatar
 
Monty committed
686

Monty's avatar
 
Monty committed
687 688 689 690
/* returns: total PCM length (samples) of content if i==-1
            PCM length (samples) of that logical bitstream for i==0 to n
	    -1 if the stream is not seekable (we can't know the length)
*/
Monty's avatar
 
Monty committed
691
int64_t ov_pcm_total(OggVorbis_File *vf,int i){
Monty's avatar
 
Monty committed
692 693
  if(!vf->seekable || i>=vf->links)return(-1);
  if(i<0){
Monty's avatar
 
Monty committed
694
    int64_t acc=0;
Monty's avatar
 
Monty committed
695 696 697 698 699 700 701 702
    int i;
    for(i=0;i<vf->links;i++)
      acc+=ov_pcm_total(vf,i);
    return(acc);
  }else{
    return(vf->pcmlengths[i]);
  }
}
Monty's avatar
 
Monty committed
703

Monty's avatar
 
Monty committed
704 705 706 707
/* returns: total seconds of content if i==-1
            seconds in that logical bitstream for i==0 to n
	    -1 if the stream is not seekable (we can't know the length)
*/
Monty's avatar
 
Monty committed
708
double ov_time_total(OggVorbis_File *vf,int i){
Monty's avatar
 
Monty committed
709 710
  if(!vf->seekable || i>=vf->links)return(-1);
  if(i<0){
Monty's avatar
 
Monty committed
711 712 713 714 715 716 717 718 719
    double acc=0;
    int i;
    for(i=0;i<vf->links;i++)
      acc+=ov_time_total(vf,i);
    return(acc);
  }else{
    return((float)(vf->pcmlengths[i])/vf->vi[i].rate);
  }
}
Monty's avatar
 
Monty committed
720

Monty's avatar
 
Monty committed
721 722 723 724
/* seek to an offset relative to the *compressed* data. This also
   immediately sucks in and decodes pages to update the PCM cursor. It
   will cross a logical bitstream boundary, but only if it can't get
   any packets out of the tail of the bitstream we seek to (so no
Monty's avatar
 
Monty committed
725 726 727
   surprises). 

   returns zero on success, nonzero on failure */
Monty's avatar
 
Monty committed
728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758

int ov_raw_seek(OggVorbis_File *vf,long pos){

  if(!vf->seekable)return(-1); /* don't dump machine if we can't seek */
  if(pos<0 || pos>vf->offsets[vf->links])goto seek_error;

  /* clear out decoding machine state */
  _decode_clear(vf);

  /* seek */
  _seek_helper(vf,pos);

  /* we need to make sure the pcm_offset is set.  We use the
     _fetch_packet helper to process one packet with readp set, then
     call it until it returns '0' with readp not set (the last packet
     from a page has the 'frameno' field set, and that's how the
     helper updates the offset */

  switch(_process_packet(vf,1)){
  case 0:
    /* oh, eof. There are no packets remaining.  Set the pcm offset to
       the end of file */
    vf->pcm_offset=ov_pcm_total(vf,-1);
    return(0);
  case -1:
    /* error! missing data or invalid bitstream structure */
    goto seek_error;
  default:
    /* all OK */
    break;
  }
Monty's avatar
 
Monty committed
759

Monty's avatar
 
Monty committed
760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779
  while(1){
    switch(_process_packet(vf,0)){
    case 0:
      /* the offset is set.  If it's a bogus bitstream with no offset
         information, it's not but that's not our fault.  We still run
         gracefully, we're just missing the offset */
      return(0);
    case -1:
      /* error! missing data or invalid bitstream structure */
      goto seek_error;
    default:
      /* continue processing packets */
      break;
    }
  }
  
 seek_error:
  /* dump the machine so we're in a known state */
  _decode_clear(vf);
  return -1;
Monty's avatar
 
Monty committed
780 781
}

Monty's avatar
 
Monty committed
782 783 784 785
/* seek to a sample offset relative to the decompressed pcm stream 

   returns zero on success, nonzero on failure */

Monty's avatar
 
Monty committed
786
int ov_pcm_seek(OggVorbis_File *vf,int64_t pos){
Monty's avatar
 
Monty committed
787
  int link=-1;
Monty's avatar
 
Monty committed
788
  int64_t total=ov_pcm_total(vf,-1);
Monty's avatar
 
Monty committed
789 790 791 792 793 794 795 796 797 798

  if(!vf->seekable)return(-1); /* don't dump machine if we can't seek */  
  if(pos<0 || pos>total)goto seek_error;

  /* which bitstream section does this pcm offset occur in? */
  for(link=vf->links-1;link>=0;link--){
    total-=vf->pcmlengths[link];
    if(pos>=total)break;
  }

Monty's avatar
 
Monty committed
799
  /* search within the logical bitstream for the page with the highest
Monty's avatar
 
Monty committed
800 801 802 803 804
     pcm_pos preceeding (or equal to) pos.  There is a danger here;
     missing pages or incorrect frame number information in the
     bitstream could make our task impossible.  Account for that (it
     would be an error condition) */
  {
Monty's avatar
 
Monty committed
805
    int64_t target=pos-total;
Monty's avatar
 
Monty committed
806 807 808 809 810 811 812
    long end=vf->offsets[link+1];
    long begin=vf->offsets[link];
    long best=begin;

    ogg_page og;
    while(begin<end){
      long bisect;
Monty's avatar
 
Monty committed
813
      long ret;
Monty's avatar
 
Monty committed
814 815 816 817 818 819 820 821
    
      if(end-begin<CHUNKSIZE){
	bisect=begin;
      }else{
	bisect=(end+begin)/2;
      }
    
      _seek_helper(vf,bisect);
Monty's avatar
 
Monty committed
822
      ret=_get_next_page(vf,&og,end-bisect);
Monty's avatar
 
Monty committed
823 824 825 826
      
      if(ret==-1){
	end=bisect;
      }else{
Monty's avatar
 
Monty committed
827
	int64_t frameno=ogg_page_frameno(&og);
Monty's avatar
 
Monty committed
828
	if(frameno<target){
Monty's avatar
 
Monty committed
829 830
	  best=ret;  /* raw offset of packet with frameno */ 
	  begin=vf->offset; /* raw offset of next packet */
Monty's avatar
 
Monty committed
831
	}else{
Monty's avatar
 
Monty committed
832
	  end=bisect;
Monty's avatar
 
Monty committed
833 834 835
	}
      }
    }
Monty's avatar
 
Monty committed
836

Monty's avatar
 
Monty committed
837 838 839 840
    /* found our page. seek to it (call raw_seek). */
    
    if(ov_raw_seek(vf,best))goto seek_error;
  }
Monty's avatar
 
Monty committed
841

Monty's avatar
 
Monty committed
842 843 844
  /* verify result */
  if(vf->pcm_offset>=pos)goto seek_error;
  if(pos>ov_pcm_total(vf,-1))goto seek_error;
Monty's avatar
 
Monty committed
845

Monty's avatar
 
Monty committed
846 847 848 849 850 851
  /* discard samples until we reach the desired position. Crossing a
     logical bitstream boundary with abandon is OK. */
  while(vf->pcm_offset<pos){
    double **pcm;
    long target=pos-vf->pcm_offset;
    long samples=vorbis_synthesis_pcmout(&vf->vd,&pcm);
Monty's avatar
 
Monty committed
852

Monty's avatar
 
Monty committed
853 854 855 856 857 858 859 860 861 862 863 864 865 866
    if(samples>target)samples=target;
    vorbis_synthesis_read(&vf->vd,samples);
    vf->pcm_offset+=samples;
    
    if(samples<target)
      if(_process_packet(vf,1)==0)
	vf->pcm_offset=ov_pcm_total(vf,-1); /* eof */
  }
  return 0;
  
 seek_error:
  /* dump machine so we're in a known state */
  _decode_clear(vf);
  return -1;
Monty's avatar
 
Monty committed
867
}
Monty's avatar
 
Monty committed
868

Monty's avatar
 
Monty committed
869 870
/* seek to a playback time relative to the decompressed pcm stream 
   returns zero on success, nonzero on failure */
Monty's avatar
 
Monty committed
871 872
int ov_time_seek(OggVorbis_File *vf,double seconds){
  /* translate time to PCM position and call ov_pcm_seek */
Monty's avatar
 
Monty committed
873

Monty's avatar
 
Monty committed
874
  int link=-1;
Monty's avatar
 
Monty committed
875
  int64_t pcm_total=ov_pcm_total(vf,-1);
Monty's avatar
 
Monty committed
876
  double time_total=ov_time_total(vf,-1);
Monty's avatar
 
Monty committed
877

Monty's avatar
 
Monty committed
878 879 880 881 882 883 884 885 886 887 888 889
  if(!vf->seekable)return(-1); /* don't dump machine if we can't seek */  
  if(seconds<0 || seconds>time_total)goto seek_error;
  
  /* which bitstream section does this time offset occur in? */
  for(link=vf->links-1;link>=0;link--){
    pcm_total-=vf->pcmlengths[link];
    time_total-=ov_time_total(vf,link);
    if(seconds>=time_total)break;
  }

  /* enough information to convert time offset to pcm offset */
  {
Monty's avatar
 
Monty committed
890
    int64_t target=pcm_total+(seconds-time_total)*vf->vi[link].rate;
Monty's avatar
 
Monty committed
891 892 893 894 895 896 897 898 899 900 901
    return(ov_pcm_seek(vf,target));
  }

 seek_error:
  /* dump machine so we're in a known state */
  _decode_clear(vf);
  return -1;
}

/* tell the current stream offset cursor.  Note that seek followed by
   tell will likely not give the set offset due to caching */
Monty's avatar
 
Monty committed
902
int64_t ov_raw_tell(OggVorbis_File *vf){
Monty's avatar
 
Monty committed
903
  return(vf->offset);
Monty's avatar
 
Monty committed
904 905
}

Monty's avatar
 
Monty committed
906
/* return PCM offset (sample) of next PCM sample to be read */
Monty's avatar
 
Monty committed
907
int64_t ov_pcm_tell(OggVorbis_File *vf){
Monty's avatar
 
Monty committed
908 909
  return(vf->pcm_offset);
}
Monty's avatar
 
Monty committed
910

Monty's avatar
 
Monty committed
911
/* return time offset (seconds) of next PCM sample to be read */
Monty's avatar
 
Monty committed
912 913
double ov_time_tell(OggVorbis_File *vf){
  /* translate time to PCM position and call ov_pcm_seek */
Monty's avatar
 
Monty committed
914

Monty's avatar
 
Monty committed
915
  int link=-1;
Monty's avatar
 
Monty committed
916
  int64_t pcm_total=0;
Monty's avatar
 
Monty committed
917 918 919 920 921 922 923 924 925 926 927 928 929
  double time_total=0.;
  
  if(vf->seekable){
    pcm_total=ov_pcm_total(vf,-1);
    time_total=ov_time_total(vf,-1);
  
    /* which bitstream section does this time offset occur in? */
    for(link=vf->links-1;link>=0;link--){
      pcm_total-=vf->pcmlengths[link];
      time_total-=ov_time_total(vf,link);
      if(vf->pcm_offset>pcm_total)break;
    }
  }
Monty's avatar
 
Monty committed
930

Monty's avatar
 
Monty committed
931
  return((double)time_total+(double)(vf->pcm_offset-pcm_total)/vf->vi[link].rate);
Monty's avatar
 
Monty committed
932 933
}

Monty's avatar
 
Monty committed
934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958
/*  link:   -1) return the vorbis_info struct for the bitstream section
                currently being decoded
           0-n) to request information for a specific bitstream section
    
    In the case of a non-seekable bitstream, any call returns the
    current bitstream.  NULL in the case that the machine is not
    initialized */

vorbis_info *ov_info(OggVorbis_File *vf,int link){
  if(vf->seekable){
    if(link<0)
      if(vf->decode_ready)
	return vf->vi+vf->current_link;
      else
	return NULL;
    else
      if(link>=vf->links)
	return NULL;
      else
	return vf->vi+link;
  }else{
    if(vf->decode_ready)
      return vf->vi;
    else
      return NULL;
Monty's avatar
 
Monty committed
959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979
  }
}

/* grr, strong typing, grr, no templates/inheritence, grr */
vorbis_comment *ov_comment(OggVorbis_File *vf,int link){
  if(vf->seekable){
    if(link<0)
      if(vf->decode_ready)
	return vf->vc+vf->current_link;
      else
	return NULL;
    else
      if(link>=vf->links)
	return NULL;
      else
	return vf->vc+link;
  }else{
    if(vf->decode_ready)
      return vf->vc;
    else
      return NULL;
Monty's avatar
 
Monty committed
980 981
  }
}
Monty's avatar
 
Monty committed
982

983 984 985 986 987 988 989 990 991
int host_is_big_endian() {
  short pattern = 0xbabe;
  unsigned char *bytewise = (unsigned char *)&pattern;
  if (bytewise[0] == 0xba) return 1;

  assert(bytewise[0] == 0xbe);
  return 0;
}

Monty's avatar
 
Monty committed
992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025
/* up to this point, everything could more or less hide the multiple
   logical bitstream nature of chaining from the toplevel application
   if the toplevel application didn't particularly care.  However, at
   the point that we actually read audio back, the multiple-section
   nature must surface: Multiple bitstream sections do not necessarily
   have to have the same number of channels or sampling rate.

   ov_read returns the sequential logical bitstream number currently
   being decoded along with the PCM data in order that the toplevel
   application can take action on channel/sample rate changes.  This
   number will be incremented even for streamed (non-seekable) streams
   (for seekable streams, it represents the actual logical bitstream
   index within the physical bitstream.  Note that the accessor
   functions above are aware of this dichotomy).

   input values: buffer) a buffer to hold packed PCM data for return
		 length) the byte length requested to be placed into buffer
		 bigendianp) should the data be packed LSB first (0) or
		             MSB first (1)
		 word) word size for output.  currently 1 (byte) or 
		       2 (16 bit short)

   return values: -1) error/hole in data
                   0) EOF
		   n) number of bytes of PCM actually returned.  The
		   below works on a packet-by-packet basis, so the
		   return length is not related to the 'length' passed
		   in, just guaranteed to fit.

	    *section) set to the logical bitstream number */

long ov_read(OggVorbis_File *vf,char *buffer,int length,
		    int bigendianp,int word,int sgned,int *bitstream){
  int i,j;
1026
  int host_endian = host_is_big_endian();
Monty's avatar
 
Monty committed
1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040

  while(1){
    if(vf->decode_ready){
      double **pcm;
      long samples=vorbis_synthesis_pcmout(&vf->vd,&pcm);
      if(samples){
	/* yay! proceed to pack data into the byte buffer */

	long channels=ov_info(vf,-1)->channels;
	long bytespersample=word * channels;
	if(samples>length/bytespersample)samples=length/bytespersample;
	
	/* a tight loop to pack each size */
	{
Michael Smith's avatar
 
Michael Smith committed
1041
	  int val;
Monty's avatar
 
Monty committed
1042 1043 1044 1045
	  if(word==1){
	    int off=(sgned?0:128);
	    for(j=0;j<samples;j++)
	      for(i=0;i<channels;i++){
Michael Smith's avatar
 
Michael Smith committed
1046
		val=(int)(pcm[i][j]*128. + 0.5);
Monty's avatar
 
Monty committed
1047
		if(val>127)val=127;
Michael Smith's avatar
 
Michael Smith committed
1048
		else if(val<-128)val=-128;
Monty's avatar
 
Monty committed
1049 1050 1051 1052 1053
		*buffer++=val+off;
	      }
	  }else{
	    int off=(sgned?0:32768);

1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080
	    if(host_endian==bigendianp){
	      if(sgned){
		for(i=0;i<channels;i++) { /* It's faster in this order */
		  double *src=pcm[i];
		  short *dest=((short *)buffer)+i;
		  for(j=0;j<samples;j++) {
		    val=(int)(src[j]*32768. + 0.5);
		    if(val>32767)val=32767;
		    else if(val<-32768)val=-32768;
		    *dest=val;
		    dest+=channels;
		  }
		}
	      }else{
		for(i=0;i<channels;i++) {
		  double *src=pcm[i];
		  short *dest=((short *)buffer)+i;
		  for(j=0;j<samples;j++) {
		    val=(int)(src[j]*32768. + 0.5);
		    if(val>32767)val=32767;
		    else if(val<-32768)val=-32768;
		    *dest=val+off;
		    dest+=channels;
		  }
		}
	      }
	    }else if(bigendianp){
Monty's avatar
 
Monty committed
1081 1082
	      for(j=0;j<samples;j++)
		for(i=0;i<channels;i++){
Michael Smith's avatar
 
Michael Smith committed
1083
		  val=(int)(pcm[i][j]*32768. + 0.5);
Monty's avatar
 
Monty committed
1084
		  if(val>32767)val=32767;
Michael Smith's avatar
 
Michael Smith committed
1085
		  else if(val<-32768)val=-32768;
Monty's avatar
 
Monty committed
1086 1087 1088 1089 1090
		  val+=off;
		  *buffer++=(val>>8);
		  *buffer++=(val&0xff);
		}
	    }else{
Michael Smith's avatar
 
Michael Smith committed
1091
	      int val;
Monty's avatar
 
Monty committed
1092
	      for(j=0;j<samples;j++)
Michael Smith's avatar
 
Michael Smith committed
1093 1094
	 	for(i=0;i<channels;i++){
		  val=(int)(pcm[i][j]*32768. + 0.5);
Monty's avatar
 
Monty committed
1095
		  if(val>32767)val=32767;
Michael Smith's avatar
 
Michael Smith committed
1096
		  else if(val<-32768)val=-32768;
Monty's avatar
 
Monty committed
1097 1098 1099
		  val+=off;
		  *buffer++=(val&0xff);
		  *buffer++=(val>>8);
Michael Smith's avatar
 
Michael Smith committed
1100
	  	}
Monty's avatar
 
Monty committed
1101 1102 1103 1104 1105 1106 1107

	    }
	  }
	}
	
	vorbis_synthesis_read(&vf->vd,samples);
	vf->pcm_offset+=samples;
Monty's avatar
 
Monty committed
1108
	if(bitstream)*bitstream=vf->current_link;
Monty's avatar
 
Monty committed
1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123
	return(samples*bytespersample);
      }
    }

    /* suck in another packet */
    switch(_process_packet(vf,1)){
    case 0:
      return(0);
    case -1:
      return -1;
    default:
      break;
    }
  }
}
Monty's avatar
 
Monty committed
1124 1125 1126



Monty's avatar
 
Monty committed
1127