1 /******************************************************************** 2 * * 3 * THIS FILE IS PART OF THE OggVorbis SOFTWARE CODEC SOURCE CODE. * 4 * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS * 5 * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE * 6 * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING. * 7 * * 8 * THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2009 * 9 * by the Xiph.Org Foundation http://www.xiph.org/ * 10 * * 11 ******************************************************************** 12 13 function: stdio-based convenience library for opening/seeking/decoding 14 last mod: $Id: vorbisfile.c 17012 2010-03-24 07:37:36Z xiphmont $ 15 16 ********************************************************************/ 17 18 #include <stdlib.h> 19 #include <stdio.h> 20 #include <errno.h> 21 #include <string.h> 22 #include <math.h> 23 24 #include "vorbis/codec.h" 25 26 /* we don't need or want the static callback symbols here */ 27 #define OV_EXCLUDE_STATIC_CALLBACKS 28 #include "vorbis/vorbisfile.h" 29 30 #include "os.h" 31 #include "misc.h" 32 33 /* A 'chained bitstream' is a Vorbis bitstream that contains more than 34 one logical bitstream arranged end to end (the only form of Ogg 35 multiplexing allowed in a Vorbis bitstream; grouping [parallel 36 multiplexing] is not allowed in Vorbis) */ 37 38 /* A Vorbis file can be played beginning to end (streamed) without 39 worrying ahead of time about chaining (see decoder_example.c). If 40 we have the whole file, however, and want random access 41 (seeking/scrubbing) or desire to know the total length/time of a 42 file, we need to account for the possibility of chaining. */ 43 44 /* We can handle things a number of ways; we can determine the entire 45 bitstream structure right off the bat, or find pieces on demand. 46 This example determines and caches structure for the entire 47 bitstream, but builds a virtual decoder on the fly when moving 48 between links in the chain. */ 49 50 /* There are also different ways to implement seeking. Enough 51 information exists in an Ogg bitstream to seek to 52 sample-granularity positions in the output. Or, one can seek by 53 picking some portion of the stream roughly in the desired area if 54 we only want coarse navigation through the stream. */ 55 56 /************************************************************************* 57 * Many, many internal helpers. The intention is not to be confusing; 58 * rampant duplication and monolithic function implementation would be 59 * harder to understand anyway. The high level functions are last. Begin 60 * grokking near the end of the file */ 61 62 /* read a little more data from the file/pipe into the ogg_sync framer 63 */ 64 #define CHUNKSIZE 65536 /* greater-than-page-size granularity seeking */ 65 #define READSIZE 2048 /* a smaller read size is needed for low-rate streaming. */ 66 67 static long _get_data(OggVorbis_File *vf){ 68 errno=0; 69 if(!(vf->callbacks.read_func))return(-1); 70 if(vf->datasource){ 71 char *buffer=ogg_sync_buffer(&vf->oy,READSIZE); 72 long bytes=(vf->callbacks.read_func)(buffer,1,READSIZE,vf->datasource); 73 if(bytes>0)ogg_sync_wrote(&vf->oy,bytes); 74 if(bytes==0 && errno)return(-1); 75 return(bytes); 76 }else 77 return(0); 78 } 79 80 /* save a tiny smidge of verbosity to make the code more readable */ 81 static int _seek_helper(OggVorbis_File *vf,ogg_int64_t offset){ 82 if(vf->datasource){ 83 if(!(vf->callbacks.seek_func)|| 84 (vf->callbacks.seek_func)(vf->datasource, offset, SEEK_SET) == -1) 85 return OV_EREAD; 86 vf->offset=offset; 87 ogg_sync_reset(&vf->oy); 88 }else{ 89 /* shouldn't happen unless someone writes a broken callback */ 90 return OV_EFAULT; 91 } 92 return 0; 93 } 94 95 /* The read/seek functions track absolute position within the stream */ 96 97 /* from the head of the stream, get the next page. boundary specifies 98 if the function is allowed to fetch more data from the stream (and 99 how much) or only use internally buffered data. 100 101 boundary: -1) unbounded search 102 0) read no additional data; use cached only 103 n) search for a new page beginning for n bytes 104 105 return: <0) did not find a page (OV_FALSE, OV_EOF, OV_EREAD) 106 n) found a page at absolute offset n */ 107 108 static ogg_int64_t _get_next_page(OggVorbis_File *vf,ogg_page *og, 109 ogg_int64_t boundary){ 110 if(boundary>0)boundary+=vf->offset; 111 while(1){ 112 long more; 113 114 if(boundary>0 && vf->offset>=boundary)return(OV_FALSE); 115 more=ogg_sync_pageseek(&vf->oy,og); 116 117 if(more<0){ 118 /* skipped n bytes */ 119 vf->offset-=more; 120 }else{ 121 if(more==0){ 122 /* send more paramedics */ 123 if(!boundary)return(OV_FALSE); 124 { 125 long ret=_get_data(vf); 126 if(ret==0)return(OV_EOF); 127 if(ret<0)return(OV_EREAD); 128 } 129 }else{ 130 /* got a page. Return the offset at the page beginning, 131 advance the internal offset past the page end */ 132 ogg_int64_t ret=vf->offset; 133 vf->offset+=more; 134 return(ret); 135 136 } 137 } 138 } 139 } 140 141 /* find the latest page beginning before the current stream cursor 142 position. Much dirtier than the above as Ogg doesn't have any 143 backward search linkage. no 'readp' as it will certainly have to 144 read. */ 145 /* returns offset or OV_EREAD, OV_FAULT */ 146 static ogg_int64_t _get_prev_page(OggVorbis_File *vf,ogg_page *og){ 147 ogg_int64_t begin=vf->offset; 148 ogg_int64_t end=begin; 149 ogg_int64_t ret; 150 ogg_int64_t offset=-1; 151 152 while(offset==-1){ 153 begin-=CHUNKSIZE; 154 if(begin<0) 155 begin=0; 156 157 ret=_seek_helper(vf,begin); 158 if(ret)return(ret); 159 160 while(vf->offset<end){ 161 memset(og,0,sizeof(*og)); 162 ret=_get_next_page(vf,og,end-vf->offset); 163 if(ret==OV_EREAD)return(OV_EREAD); 164 if(ret<0){ 165 break; 166 }else{ 167 offset=ret; 168 } 169 } 170 } 171 172 /* In a fully compliant, non-multiplexed stream, we'll still be 173 holding the last page. In multiplexed (or noncompliant streams), 174 we will probably have to re-read the last page we saw */ 175 if(og->header_len==0){ 176 ret=_seek_helper(vf,offset); 177 if(ret)return(ret); 178 179 ret=_get_next_page(vf,og,CHUNKSIZE); 180 if(ret<0) 181 /* this shouldn't be possible */ 182 return(OV_EFAULT); 183 } 184 185 return(offset); 186 } 187 188 static void _add_serialno(ogg_page *og,long **serialno_list, int *n){ 189 long s = ogg_page_serialno(og); 190 (*n)++; 191 192 if(*serialno_list){ 193 *serialno_list = _ogg_realloc(*serialno_list, sizeof(**serialno_list)*(*n)); 194 }else{ 195 *serialno_list = _ogg_malloc(sizeof(**serialno_list)); 196 } 197 198 (*serialno_list)[(*n)-1] = s; 199 } 200 201 /* returns nonzero if found */ 202 static int _lookup_serialno(long s, long *serialno_list, int n){ 203 if(serialno_list){ 204 while(n--){ 205 if(*serialno_list == s) return 1; 206 serialno_list++; 207 } 208 } 209 return 0; 210 } 211 212 static int _lookup_page_serialno(ogg_page *og, long *serialno_list, int n){ 213 long s = ogg_page_serialno(og); 214 return _lookup_serialno(s,serialno_list,n); 215 } 216 217 /* performs the same search as _get_prev_page, but prefers pages of 218 the specified serial number. If a page of the specified serialno is 219 spotted during the seek-back-and-read-forward, it will return the 220 info of last page of the matching serial number instead of the very 221 last page. If no page of the specified serialno is seen, it will 222 return the info of last page and alter *serialno. */ 223 static ogg_int64_t _get_prev_page_serial(OggVorbis_File *vf, 224 long *serial_list, int serial_n, 225 int *serialno, ogg_int64_t *granpos){ 226 ogg_page og; 227 ogg_int64_t begin=vf->offset; 228 ogg_int64_t end=begin; 229 ogg_int64_t ret; 230 231 ogg_int64_t prefoffset=-1; 232 ogg_int64_t offset=-1; 233 ogg_int64_t ret_serialno=-1; 234 ogg_int64_t ret_gran=-1; 235 236 while(offset==-1){ 237 begin-=CHUNKSIZE; 238 if(begin<0) 239 begin=0; 240 241 ret=_seek_helper(vf,begin); 242 if(ret)return(ret); 243 244 while(vf->offset<end){ 245 ret=_get_next_page(vf,&og,end-vf->offset); 246 if(ret==OV_EREAD)return(OV_EREAD); 247 if(ret<0){ 248 break; 249 }else{ 250 ret_serialno=ogg_page_serialno(&og); 251 ret_gran=ogg_page_granulepos(&og); 252 offset=ret; 253 254 if(ret_serialno == *serialno){ 255 prefoffset=ret; 256 *granpos=ret_gran; 257 } 258 259 if(!_lookup_serialno(ret_serialno,serial_list,serial_n)){ 260 /* we fell off the end of the link, which means we seeked 261 back too far and shouldn't have been looking in that link 262 to begin with. If we found the preferred serial number, 263 forget that we saw it. */ 264 prefoffset=-1; 265 } 266 } 267 } 268 } 269 270 /* we're not interested in the page... just the serialno and granpos. */ 271 if(prefoffset>=0)return(prefoffset); 272 273 *serialno = ret_serialno; 274 *granpos = ret_gran; 275 return(offset); 276 277 } 278 279 /* uses the local ogg_stream storage in vf; this is important for 280 non-streaming input sources */ 281 static int _fetch_headers(OggVorbis_File *vf,vorbis_info *vi,vorbis_comment *vc, 282 long **serialno_list, int *serialno_n, 283 ogg_page *og_ptr){ 284 ogg_page og; 285 ogg_packet op; 286 int i,ret; 287 int allbos=0; 288 289 if(!og_ptr){ 290 ogg_int64_t llret=_get_next_page(vf,&og,CHUNKSIZE); 291 if(llret==OV_EREAD)return(OV_EREAD); 292 if(llret<0)return(OV_ENOTVORBIS); 293 og_ptr=&og; 294 } 295 296 vorbis_info_init(vi); 297 vorbis_comment_init(vc); 298 vf->ready_state=OPENED; 299 300 /* extract the serialnos of all BOS pages + the first set of vorbis 301 headers we see in the link */ 302 303 while(ogg_page_bos(og_ptr)){ 304 if(serialno_list){ 305 if(_lookup_page_serialno(og_ptr,*serialno_list,*serialno_n)){ 306 /* a dupe serialnumber in an initial header packet set == invalid stream */ 307 if(*serialno_list)_ogg_free(*serialno_list); 308 *serialno_list=0; 309 *serialno_n=0; 310 ret=OV_EBADHEADER; 311 goto bail_header; 312 } 313 314 _add_serialno(og_ptr,serialno_list,serialno_n); 315 } 316 317 if(vf->ready_state<STREAMSET){ 318 /* we don't have a vorbis stream in this link yet, so begin 319 prospective stream setup. We need a stream to get packets */ 320 ogg_stream_reset_serialno(&vf->os,ogg_page_serialno(og_ptr)); 321 ogg_stream_pagein(&vf->os,og_ptr); 322 323 if(ogg_stream_packetout(&vf->os,&op) > 0 && 324 vorbis_synthesis_idheader(&op)){ 325 /* vorbis header; continue setup */ 326 vf->ready_state=STREAMSET; 327 if((ret=vorbis_synthesis_headerin(vi,vc,&op))){ 328 ret=OV_EBADHEADER; 329 goto bail_header; 330 } 331 } 332 } 333 334 /* get next page */ 335 { 336 ogg_int64_t llret=_get_next_page(vf,og_ptr,CHUNKSIZE); 337 if(llret==OV_EREAD){ 338 ret=OV_EREAD; 339 goto bail_header; 340 } 341 if(llret<0){ 342 ret=OV_ENOTVORBIS; 343 goto bail_header; 344 } 345 346 /* if this page also belongs to our vorbis stream, submit it and break */ 347 if(vf->ready_state==STREAMSET && 348 vf->os.serialno == ogg_page_serialno(og_ptr)){ 349 ogg_stream_pagein(&vf->os,og_ptr); 350 break; 351 } 352 } 353 } 354 355 if(vf->ready_state!=STREAMSET){ 356 ret = OV_ENOTVORBIS; 357 goto bail_header; 358 } 359 360 while(1){ 361 362 i=0; 363 while(i<2){ /* get a page loop */ 364 365 while(i<2){ /* get a packet loop */ 366 367 int result=ogg_stream_packetout(&vf->os,&op); 368 if(result==0)break; 369 if(result==-1){ 370 ret=OV_EBADHEADER; 371 goto bail_header; 372 } 373 374 if((ret=vorbis_synthesis_headerin(vi,vc,&op))) 375 goto bail_header; 376 377 i++; 378 } 379 380 while(i<2){ 381 if(_get_next_page(vf,og_ptr,CHUNKSIZE)<0){ 382 ret=OV_EBADHEADER; 383 goto bail_header; 384 } 385 386 /* if this page belongs to the correct stream, go parse it */ 387 if(vf->os.serialno == ogg_page_serialno(og_ptr)){ 388 ogg_stream_pagein(&vf->os,og_ptr); 389 break; 390 } 391 392 /* if we never see the final vorbis headers before the link 393 ends, abort */ 394 if(ogg_page_bos(og_ptr)){ 395 if(allbos){ 396 ret = OV_EBADHEADER; 397 goto bail_header; 398 }else 399 allbos=1; 400 } 401 402 /* otherwise, keep looking */ 403 } 404 } 405 406 return 0; 407 } 408 409 bail_header: 410 vorbis_info_clear(vi); 411 vorbis_comment_clear(vc); 412 vf->ready_state=OPENED; 413 414 return ret; 415 } 416 417 /* Starting from current cursor position, get initial PCM offset of 418 next page. Consumes the page in the process without decoding 419 audio, however this is only called during stream parsing upon 420 seekable open. */ 421 static ogg_int64_t _initial_pcmoffset(OggVorbis_File *vf, vorbis_info *vi){ 422 ogg_page og; 423 ogg_int64_t accumulated=0; 424 long lastblock=-1; 425 int result; 426 int serialno = vf->os.serialno; 427 428 while(1){ 429 ogg_packet op; 430 if(_get_next_page(vf,&og,-1)<0) 431 break; /* should not be possible unless the file is truncated/mangled */ 432 433 if(ogg_page_bos(&og)) break; 434 if(ogg_page_serialno(&og)!=serialno) continue; 435 436 /* count blocksizes of all frames in the page */ 437 ogg_stream_pagein(&vf->os,&og); 438 while((result=ogg_stream_packetout(&vf->os,&op))){ 439 if(result>0){ /* ignore holes */ 440 long thisblock=vorbis_packet_blocksize(vi,&op); 441 if(lastblock!=-1) 442 accumulated+=(lastblock+thisblock)>>2; 443 lastblock=thisblock; 444 } 445 } 446 447 if(ogg_page_granulepos(&og)!=-1){ 448 /* pcm offset of last packet on the first audio page */ 449 accumulated= ogg_page_granulepos(&og)-accumulated; 450 break; 451 } 452 } 453 454 /* less than zero? This is a stream with samples trimmed off 455 the beginning, a normal occurrence; set the offset to zero */ 456 if(accumulated<0)accumulated=0; 457 458 return accumulated; 459 } 460 461 /* finds each bitstream link one at a time using a bisection search 462 (has to begin by knowing the offset of the lb's initial page). 463 Recurses for each link so it can alloc the link storage after 464 finding them all, then unroll and fill the cache at the same time */ 465 static int _bisect_forward_serialno(OggVorbis_File *vf, 466 ogg_int64_t begin, 467 ogg_int64_t searched, 468 ogg_int64_t end, 469 ogg_int64_t endgran, 470 int endserial, 471 long *currentno_list, 472 int currentnos, 473 long m){ 474 ogg_int64_t pcmoffset; 475 ogg_int64_t dataoffset=searched; 476 ogg_int64_t endsearched=end; 477 ogg_int64_t next=end; 478 ogg_int64_t searchgran=-1; 479 ogg_page og; 480 ogg_int64_t ret,last; 481 int serialno = vf->os.serialno; 482 483 /* invariants: 484 we have the headers and serialnos for the link beginning at 'begin' 485 we have the offset and granpos of the last page in the file (potentially 486 not a page we care about) 487 */ 488 489 /* Is the last page in our list of current serialnumbers? */ 490 if(_lookup_serialno(endserial,currentno_list,currentnos)){ 491 492 /* last page is in the starting serialno list, so we've bisected 493 down to (or just started with) a single link. Now we need to 494 find the last vorbis page belonging to the first vorbis stream 495 for this link. */ 496 497 while(endserial != serialno){ 498 endserial = serialno; 499 vf->offset=_get_prev_page_serial(vf,currentno_list,currentnos,&endserial,&endgran); 500 } 501 502 vf->links=m+1; 503 if(vf->offsets)_ogg_free(vf->offsets); 504 if(vf->serialnos)_ogg_free(vf->serialnos); 505 if(vf->dataoffsets)_ogg_free(vf->dataoffsets); 506 507 vf->offsets=_ogg_malloc((vf->links+1)*sizeof(*vf->offsets)); 508 vf->vi=_ogg_realloc(vf->vi,vf->links*sizeof(*vf->vi)); 509 vf->vc=_ogg_realloc(vf->vc,vf->links*sizeof(*vf->vc)); 510 vf->serialnos=_ogg_malloc(vf->links*sizeof(*vf->serialnos)); 511 vf->dataoffsets=_ogg_malloc(vf->links*sizeof(*vf->dataoffsets)); 512 vf->pcmlengths=_ogg_malloc(vf->links*2*sizeof(*vf->pcmlengths)); 513 514 vf->offsets[m+1]=end; 515 vf->offsets[m]=begin; 516 vf->pcmlengths[m*2+1]=endgran; 517 518 }else{ 519 520 long *next_serialno_list=NULL; 521 int next_serialnos=0; 522 vorbis_info vi; 523 vorbis_comment vc; 524 525 /* the below guards against garbage seperating the last and 526 first pages of two links. */ 527 while(searched<endsearched){ 528 ogg_int64_t bisect; 529 530 if(endsearched-searched<CHUNKSIZE){ 531 bisect=searched; 532 }else{ 533 bisect=(searched+endsearched)/2; 534 } 535 536 ret=_seek_helper(vf,bisect); 537 if(ret)return(ret); 538 539 last=_get_next_page(vf,&og,-1); 540 if(last==OV_EREAD)return(OV_EREAD); 541 if(last<0 || !_lookup_page_serialno(&og,currentno_list,currentnos)){ 542 endsearched=bisect; 543 if(last>=0)next=last; 544 }else{ 545 searched=last+og.header_len+og.body_len; 546 } 547 } 548 549 /* Bisection point found */ 550 551 /* for the time being, fetch end PCM offset the simple way */ 552 { 553 int testserial = serialno+1; 554 vf->offset = next; 555 while(testserial != serialno){ 556 testserial = serialno; 557 vf->offset=_get_prev_page_serial(vf,currentno_list,currentnos,&testserial,&searchgran); 558 } 559 } 560 561 if(vf->offset!=next){ 562 ret=_seek_helper(vf,next); 563 if(ret)return(ret); 564 } 565 566 ret=_fetch_headers(vf,&vi,&vc,&next_serialno_list,&next_serialnos,NULL); 567 if(ret)return(ret); 568 serialno = vf->os.serialno; 569 dataoffset = vf->offset; 570 571 /* this will consume a page, however the next bistection always 572 starts with a raw seek */ 573 pcmoffset = _initial_pcmoffset(vf,&vi); 574 575 ret=_bisect_forward_serialno(vf,next,vf->offset,end,endgran,endserial, 576 next_serialno_list,next_serialnos,m+1); 577 if(ret)return(ret); 578 579 if(next_serialno_list)_ogg_free(next_serialno_list); 580 581 vf->offsets[m+1]=next; 582 vf->serialnos[m+1]=serialno; 583 vf->dataoffsets[m+1]=dataoffset; 584 585 vf->vi[m+1]=vi; 586 vf->vc[m+1]=vc; 587 588 vf->pcmlengths[m*2+1]=searchgran; 589 vf->pcmlengths[m*2+2]=pcmoffset; 590 vf->pcmlengths[m*2+3]-=pcmoffset; 591 592 } 593 return(0); 594 } 595 596 static int _make_decode_ready(OggVorbis_File *vf){ 597 if(vf->ready_state>STREAMSET)return 0; 598 if(vf->ready_state<STREAMSET)return OV_EFAULT; 599 if(vf->seekable){ 600 if(vorbis_synthesis_init(&vf->vd,vf->vi+vf->current_link)) 601 return OV_EBADLINK; 602 }else{ 603 if(vorbis_synthesis_init(&vf->vd,vf->vi)) 604 return OV_EBADLINK; 605 } 606 vorbis_block_init(&vf->vd,&vf->vb); 607 vf->ready_state=INITSET; 608 vf->bittrack=0.f; 609 vf->samptrack=0.f; 610 return 0; 611 } 612 613 static int _open_seekable2(OggVorbis_File *vf){ 614 ogg_int64_t dataoffset=vf->dataoffsets[0],end,endgran=-1; 615 int endserial=vf->os.serialno; 616 int serialno=vf->os.serialno; 617 618 /* we're partially open and have a first link header state in 619 storage in vf */ 620 621 /* fetch initial PCM offset */ 622 ogg_int64_t pcmoffset = _initial_pcmoffset(vf,vf->vi); 623 624 /* we can seek, so set out learning all about this file */ 625 if(vf->callbacks.seek_func && vf->callbacks.tell_func){ 626 (vf->callbacks.seek_func)(vf->datasource,0,SEEK_END); 627 vf->offset=vf->end=(vf->callbacks.tell_func)(vf->datasource); 628 }else{ 629 vf->offset=vf->end=-1; 630 } 631 632 /* If seek_func is implemented, tell_func must also be implemented */ 633 if(vf->end==-1) return(OV_EINVAL); 634 635 /* Get the offset of the last page of the physical bitstream, or, if 636 we're lucky the last vorbis page of this link as most OggVorbis 637 files will contain a single logical bitstream */ 638 end=_get_prev_page_serial(vf,vf->serialnos+2,vf->serialnos[1],&endserial,&endgran); 639 if(end<0)return(end); 640 641 /* now determine bitstream structure recursively */ 642 if(_bisect_forward_serialno(vf,0,dataoffset,vf->offset,endgran,endserial, 643 vf->serialnos+2,vf->serialnos[1],0)<0)return(OV_EREAD); 644 645 vf->offsets[0]=0; 646 vf->serialnos[0]=serialno; 647 vf->dataoffsets[0]=dataoffset; 648 vf->pcmlengths[0]=pcmoffset; 649 vf->pcmlengths[1]-=pcmoffset; 650 651 return(ov_raw_seek(vf,dataoffset)); 652 } 653 654 /* clear out the current logical bitstream decoder */ 655 static void _decode_clear(OggVorbis_File *vf){ 656 vorbis_dsp_clear(&vf->vd); 657 vorbis_block_clear(&vf->vb); 658 vf->ready_state=OPENED; 659 } 660 661 /* fetch and process a packet. Handles the case where we're at a 662 bitstream boundary and dumps the decoding machine. If the decoding 663 machine is unloaded, it loads it. It also keeps pcm_offset up to 664 date (seek and read both use this. seek uses a special hack with 665 readp). 666 667 return: <0) error, OV_HOLE (lost packet) or OV_EOF 668 0) need more data (only if readp==0) 669 1) got a packet 670 */ 671 672 static int _fetch_and_process_packet(OggVorbis_File *vf, 673 ogg_packet *op_in, 674 int readp, 675 int spanp){ 676 ogg_page og; 677 678 /* handle one packet. Try to fetch it from current stream state */ 679 /* extract packets from page */ 680 while(1){ 681 682 if(vf->ready_state==STREAMSET){ 683 int ret=_make_decode_ready(vf); 684 if(ret<0)return ret; 685 } 686 687 /* process a packet if we can. */ 688 689 if(vf->ready_state==INITSET){ 690 while(1) { 691 ogg_packet op; 692 ogg_packet *op_ptr=(op_in?op_in:&op); 693 int result=ogg_stream_packetout(&vf->os,op_ptr); 694 ogg_int64_t granulepos; 695 696 op_in=NULL; 697 if(result==-1)return(OV_HOLE); /* hole in the data. */ 698 if(result>0){ 699 /* got a packet. process it */ 700 granulepos=op_ptr->granulepos; 701 if(!vorbis_synthesis(&vf->vb,op_ptr)){ /* lazy check for lazy 702 header handling. The 703 header packets aren't 704 audio, so if/when we 705 submit them, 706 vorbis_synthesis will 707 reject them */ 708 709 /* suck in the synthesis data and track bitrate */ 710 { 711 int oldsamples=vorbis_synthesis_pcmout(&vf->vd,NULL); 712 /* for proper use of libvorbis within libvorbisfile, 713 oldsamples will always be zero. */ 714 if(oldsamples)return(OV_EFAULT); 715 716 vorbis_synthesis_blockin(&vf->vd,&vf->vb); 717 vf->samptrack+=vorbis_synthesis_pcmout(&vf->vd,NULL)-oldsamples; 718 vf->bittrack+=op_ptr->bytes*8; 719 } 720 721 /* update the pcm offset. */ 722 if(granulepos!=-1 && !op_ptr->e_o_s){ 723 int link=(vf->seekable?vf->current_link:0); 724 int i,samples; 725 726 /* this packet has a pcm_offset on it (the last packet 727 completed on a page carries the offset) After processing 728 (above), we know the pcm position of the *last* sample 729 ready to be returned. Find the offset of the *first* 730 731 As an aside, this trick is inaccurate if we begin 732 reading anew right at the last page; the end-of-stream 733 granulepos declares the last frame in the stream, and the 734 last packet of the last page may be a partial frame. 735 So, we need a previous granulepos from an in-sequence page 736 to have a reference point. Thus the !op_ptr->e_o_s clause 737 above */ 738 739 if(vf->seekable && link>0) 740 granulepos-=vf->pcmlengths[link*2]; 741 if(granulepos<0)granulepos=0; /* actually, this 742 shouldn't be possible 743 here unless the stream 744 is very broken */ 745 746 samples=vorbis_synthesis_pcmout(&vf->vd,NULL); 747 748 granulepos-=samples; 749 for(i=0;i<link;i++) 750 granulepos+=vf->pcmlengths[i*2+1]; 751 vf->pcm_offset=granulepos; 752 } 753 return(1); 754 } 755 } 756 else 757 break; 758 } 759 } 760 761 if(vf->ready_state>=OPENED){ 762 ogg_int64_t ret; 763 764 while(1){ 765 /* the loop is not strictly necessary, but there's no sense in 766 doing the extra checks of the larger loop for the common 767 case in a multiplexed bistream where the page is simply 768 part of a different logical bitstream; keep reading until 769 we get one with the correct serialno */ 770 771 if(!readp)return(0); 772 if((ret=_get_next_page(vf,&og,-1))<0){ 773 return(OV_EOF); /* eof. leave unitialized */ 774 } 775 776 /* bitrate tracking; add the header's bytes here, the body bytes 777 are done by packet above */ 778 vf->bittrack+=og.header_len*8; 779 780 if(vf->ready_state==INITSET){ 781 if(vf->current_serialno!=ogg_page_serialno(&og)){ 782 783 /* two possibilities: 784 1) our decoding just traversed a bitstream boundary 785 2) another stream is multiplexed into this logical section */ 786 787 if(ogg_page_bos(&og)){ 788 /* boundary case */ 789 if(!spanp) 790 return(OV_EOF); 791 792 _decode_clear(vf); 793 794 if(!vf->seekable){ 795 vorbis_info_clear(vf->vi); 796 vorbis_comment_clear(vf->vc); 797 } 798 break; 799 800 }else 801 continue; /* possibility #2 */ 802 } 803 } 804 805 break; 806 } 807 } 808 809 /* Do we need to load a new machine before submitting the page? */ 810 /* This is different in the seekable and non-seekable cases. 811 812 In the seekable case, we already have all the header 813 information loaded and cached; we just initialize the machine 814 with it and continue on our merry way. 815 816 In the non-seekable (streaming) case, we'll only be at a 817 boundary if we just left the previous logical bitstream and 818 we're now nominally at the header of the next bitstream 819 */ 820 821 if(vf->ready_state!=INITSET){ 822 int link; 823 824 if(vf->ready_state<STREAMSET){ 825 if(vf->seekable){ 826 long serialno = ogg_page_serialno(&og); 827 828 /* match the serialno to bitstream section. We use this rather than 829 offset positions to avoid problems near logical bitstream 830 boundaries */ 831 832 for(link=0;link<vf->links;link++) 833 if(vf->serialnos[link]==serialno)break; 834 835 if(link==vf->links) continue; /* not the desired Vorbis 836 bitstream section; keep 837 trying */ 838 839 vf->current_serialno=serialno; 840 vf->current_link=link; 841 842 ogg_stream_reset_serialno(&vf->os,vf->current_serialno); 843 vf->ready_state=STREAMSET; 844 845 }else{ 846 /* we're streaming */ 847 /* fetch the three header packets, build the info struct */ 848 849 int ret=_fetch_headers(vf,vf->vi,vf->vc,NULL,NULL,&og); 850 if(ret)return(ret); 851 vf->current_serialno=vf->os.serialno; 852 vf->current_link++; 853 link=0; 854 } 855 } 856 } 857 858 /* the buffered page is the data we want, and we're ready for it; 859 add it to the stream state */ 860 ogg_stream_pagein(&vf->os,&og); 861 862 } 863 } 864 865 /* if, eg, 64 bit stdio is configured by default, this will build with 866 fseek64 */ 867 static int _fseek64_wrap(FILE *f,ogg_int64_t off,int whence){ 868 if(f==NULL)return(-1); 869 return fseek(f,off,whence); 870 } 871 872 static int _ov_open1(void *f,OggVorbis_File *vf,char *initial, 873 long ibytes, ov_callbacks callbacks){ 874 int offsettest=((f && callbacks.seek_func)?callbacks.seek_func(f,0,SEEK_CUR):-1); 875 long *serialno_list=NULL; 876 int serialno_list_size=0; 877 int ret; 878 879 memset(vf,0,sizeof(*vf)); 880 vf->datasource=f; 881 vf->callbacks = callbacks; 882 883 /* init the framing state */ 884 ogg_sync_init(&vf->oy); 885 886 /* perhaps some data was previously read into a buffer for testing 887 against other stream types. Allow initialization from this 888 previously read data (especially as we may be reading from a 889 non-seekable stream) */ 890 if(initial){ 891 char *buffer=ogg_sync_buffer(&vf->oy,ibytes); 892 memcpy(buffer,initial,ibytes); 893 ogg_sync_wrote(&vf->oy,ibytes); 894 } 895 896 /* can we seek? Stevens suggests the seek test was portable */ 897 if(offsettest!=-1)vf->seekable=1; 898 899 /* No seeking yet; Set up a 'single' (current) logical bitstream 900 entry for partial open */ 901 vf->links=1; 902 vf->vi=_ogg_calloc(vf->links,sizeof(*vf->vi)); 903 vf->vc=_ogg_calloc(vf->links,sizeof(*vf->vc)); 904 ogg_stream_init(&vf->os,-1); /* fill in the serialno later */ 905 906 /* Fetch all BOS pages, store the vorbis header and all seen serial 907 numbers, load subsequent vorbis setup headers */ 908 if((ret=_fetch_headers(vf,vf->vi,vf->vc,&serialno_list,&serialno_list_size,NULL))<0){ 909 vf->datasource=NULL; 910 ov_clear(vf); 911 }else{ 912 /* serial number list for first link needs to be held somewhere 913 for second stage of seekable stream open; this saves having to 914 seek/reread first link's serialnumber data then. */ 915 vf->serialnos=_ogg_calloc(serialno_list_size+2,sizeof(*vf->serialnos)); 916 vf->serialnos[0]=vf->current_serialno; 917 vf->serialnos[1]=serialno_list_size; 918 memcpy(vf->serialnos+2,serialno_list,serialno_list_size*sizeof(*vf->serialnos)); 919 920 vf->offsets=_ogg_calloc(1,sizeof(*vf->offsets)); 921 vf->dataoffsets=_ogg_calloc(1,sizeof(*vf->dataoffsets)); 922 vf->offsets[0]=0; 923 vf->dataoffsets[0]=vf->offset; 924 vf->current_serialno=vf->os.serialno; 925 926 vf->ready_state=PARTOPEN; 927 } 928 if(serialno_list)_ogg_free(serialno_list); 929 return(ret); 930 } 931 932 static int _ov_open2(OggVorbis_File *vf){ 933 if(vf->ready_state != PARTOPEN) return OV_EINVAL; 934 vf->ready_state=OPENED; 935 if(vf->seekable){ 936 int ret=_open_seekable2(vf); 937 if(ret){ 938 vf->datasource=NULL; 939 ov_clear(vf); 940 } 941 return(ret); 942 }else 943 vf->ready_state=STREAMSET; 944 945 return 0; 946 } 947 948 949 /* clear out the OggVorbis_File struct */ 950 int ov_clear(OggVorbis_File *vf){ 951 if(vf){ 952 vorbis_block_clear(&vf->vb); 953 vorbis_dsp_clear(&vf->vd); 954 ogg_stream_clear(&vf->os); 955 956 if(vf->vi && vf->links){ 957 int i; 958 for(i=0;i<vf->links;i++){ 959 vorbis_info_clear(vf->vi+i); 960 vorbis_comment_clear(vf->vc+i); 961 } 962 _ogg_free(vf->vi); 963 _ogg_free(vf->vc); 964 } 965 if(vf->dataoffsets)_ogg_free(vf->dataoffsets); 966 if(vf->pcmlengths)_ogg_free(vf->pcmlengths); 967 if(vf->serialnos)_ogg_free(vf->serialnos); 968 if(vf->offsets)_ogg_free(vf->offsets); 969 ogg_sync_clear(&vf->oy); 970 if(vf->datasource && vf->callbacks.close_func) 971 (vf->callbacks.close_func)(vf->datasource); 972 memset(vf,0,sizeof(*vf)); 973 } 974 #ifdef DEBUG_LEAKS 975 _VDBG_dump(); 976 #endif 977 return(0); 978 } 979 980 /* inspects the OggVorbis file and finds/documents all the logical 981 bitstreams contained in it. Tries to be tolerant of logical 982 bitstream sections that are truncated/woogie. 983 984 return: -1) error 985 0) OK 986 */ 987 988 int ov_open_callbacks(void *f,OggVorbis_File *vf,char *initial,long ibytes, 989 ov_callbacks callbacks){ 990 int ret=_ov_open1(f,vf,initial,ibytes,callbacks); 991 if(ret)return ret; 992 return _ov_open2(vf); 993 } 994 995 int ov_open(FILE *f,OggVorbis_File *vf,char *initial,long ibytes){ 996 ov_callbacks callbacks = { 997 (size_t (*)(void *, size_t, size_t, void *)) fread, 998 (int (*)(void *, ogg_int64_t, int)) _fseek64_wrap, 999 (int (*)(void *)) fclose, 1000 (long (*)(void *)) ftell 1001 }; 1002 1003 return ov_open_callbacks((void *)f, vf, initial, ibytes, callbacks); 1004 } 1005 1006 int ov_fopen(char *path,OggVorbis_File *vf){ 1007 int ret; 1008 FILE *f = fopen(path,"rb"); 1009 if(!f) return -1; 1010 1011 ret = ov_open(f,vf,NULL,0); 1012 if(ret) fclose(f); 1013 return ret; 1014 } 1015 1016 1017 /* cheap hack for game usage where downsampling is desirable; there's 1018 no need for SRC as we can just do it cheaply in libvorbis. */ 1019 1020 int ov_halfrate(OggVorbis_File *vf,int flag){ 1021 int i; 1022 if(vf->vi==NULL)return OV_EINVAL; 1023 if(!vf->seekable)return OV_EINVAL; 1024 if(vf->ready_state>=STREAMSET) 1025 _decode_clear(vf); /* clear out stream state; later on libvorbis 1026 will be able to swap this on the fly, but 1027 for now dumping the decode machine is needed 1028 to reinit the MDCT lookups. 1.1 libvorbis 1029 is planned to be able to switch on the fly */ 1030 1031 for(i=0;i<vf->links;i++){ 1032 if(vorbis_synthesis_halfrate(vf->vi+i,flag)){ 1033 ov_halfrate(vf,0); 1034 return OV_EINVAL; 1035 } 1036 } 1037 return 0; 1038 } 1039 1040 int ov_halfrate_p(OggVorbis_File *vf){ 1041 if(vf->vi==NULL)return OV_EINVAL; 1042 return vorbis_synthesis_halfrate_p(vf->vi); 1043 } 1044 1045 /* Only partially open the vorbis file; test for Vorbisness, and load 1046 the headers for the first chain. Do not seek (although test for 1047 seekability). Use ov_test_open to finish opening the file, else 1048 ov_clear to close/free it. Same return codes as open. */ 1049 1050 int ov_test_callbacks(void *f,OggVorbis_File *vf,char *initial,long ibytes, 1051 ov_callbacks callbacks) 1052 { 1053 return _ov_open1(f,vf,initial,ibytes,callbacks); 1054 } 1055 1056 int ov_test(FILE *f,OggVorbis_File *vf,char *initial,long ibytes){ 1057 ov_callbacks callbacks = { 1058 (size_t (*)(void *, size_t, size_t, void *)) fread, 1059 (int (*)(void *, ogg_int64_t, int)) _fseek64_wrap, 1060 (int (*)(void *)) fclose, 1061 (long (*)(void *)) ftell 1062 }; 1063 1064 return ov_test_callbacks((void *)f, vf, initial, ibytes, callbacks); 1065 } 1066 1067 int ov_test_open(OggVorbis_File *vf){ 1068 if(vf->ready_state!=PARTOPEN)return(OV_EINVAL); 1069 return _ov_open2(vf); 1070 } 1071 1072 /* How many logical bitstreams in this physical bitstream? */ 1073 long ov_streams(OggVorbis_File *vf){ 1074 return vf->links; 1075 } 1076 1077 /* Is the FILE * associated with vf seekable? */ 1078 long ov_seekable(OggVorbis_File *vf){ 1079 return vf->seekable; 1080 } 1081 1082 /* returns the bitrate for a given logical bitstream or the entire 1083 physical bitstream. If the file is open for random access, it will 1084 find the *actual* average bitrate. If the file is streaming, it 1085 returns the nominal bitrate (if set) else the average of the 1086 upper/lower bounds (if set) else -1 (unset). 1087 1088 If you want the actual bitrate field settings, get them from the 1089 vorbis_info structs */ 1090 1091 long ov_bitrate(OggVorbis_File *vf,int i){ 1092 if(vf->ready_state<OPENED)return(OV_EINVAL); 1093 if(i>=vf->links)return(OV_EINVAL); 1094 if(!vf->seekable && i!=0)return(ov_bitrate(vf,0)); 1095 if(i<0){ 1096 ogg_int64_t bits=0; 1097 int i; 1098 float br; 1099 for(i=0;i<vf->links;i++) 1100 bits+=(vf->offsets[i+1]-vf->dataoffsets[i])*8; 1101 /* This once read: return(rint(bits/ov_time_total(vf,-1))); 1102 * gcc 3.x on x86 miscompiled this at optimisation level 2 and above, 1103 * so this is slightly transformed to make it work. 1104 */ 1105 br = bits/ov_time_total(vf,-1); 1106 return(rint(br)); 1107 }else{ 1108 if(vf->seekable){ 1109 /* return the actual bitrate */ 1110 return(rint((vf->offsets[i+1]-vf->dataoffsets[i])*8/ov_time_total(vf,i))); 1111 }else{ 1112 /* return nominal if set */ 1113 if(vf->vi[i].bitrate_nominal>0){ 1114 return vf->vi[i].bitrate_nominal; 1115 }else{ 1116 if(vf->vi[i].bitrate_upper>0){ 1117 if(vf->vi[i].bitrate_lower>0){ 1118 return (vf->vi[i].bitrate_upper+vf->vi[i].bitrate_lower)/2; 1119 }else{ 1120 return vf->vi[i].bitrate_upper; 1121 } 1122 } 1123 return(OV_FALSE); 1124 } 1125 } 1126 } 1127 } 1128 1129 /* returns the actual bitrate since last call. returns -1 if no 1130 additional data to offer since last call (or at beginning of stream), 1131 EINVAL if stream is only partially open 1132 */ 1133 long ov_bitrate_instant(OggVorbis_File *vf){ 1134 int link=(vf->seekable?vf->current_link:0); 1135 long ret; 1136 if(vf->ready_state<OPENED)return(OV_EINVAL); 1137 if(vf->samptrack==0)return(OV_FALSE); 1138 ret=vf->bittrack/vf->samptrack*vf->vi[link].rate+.5; 1139 vf->bittrack=0.f; 1140 vf->samptrack=0.f; 1141 return(ret); 1142 } 1143 1144 /* Guess */ 1145 long ov_serialnumber(OggVorbis_File *vf,int i){ 1146 if(i>=vf->links)return(ov_serialnumber(vf,vf->links-1)); 1147 if(!vf->seekable && i>=0)return(ov_serialnumber(vf,-1)); 1148 if(i<0){ 1149 return(vf->current_serialno); 1150 }else{ 1151 return(vf->serialnos[i]); 1152 } 1153 } 1154 1155 /* returns: total raw (compressed) length of content if i==-1 1156 raw (compressed) length of that logical bitstream for i==0 to n 1157 OV_EINVAL if the stream is not seekable (we can't know the length) 1158 or if stream is only partially open 1159 */ 1160 ogg_int64_t ov_raw_total(OggVorbis_File *vf,int i){ 1161 if(vf->ready_state<OPENED)return(OV_EINVAL); 1162 if(!vf->seekable || i>=vf->links)return(OV_EINVAL); 1163 if(i<0){ 1164 ogg_int64_t acc=0; 1165 int i; 1166 for(i=0;i<vf->links;i++) 1167 acc+=ov_raw_total(vf,i); 1168 return(acc); 1169 }else{ 1170 return(vf->offsets[i+1]-vf->offsets[i]); 1171 } 1172 } 1173 1174 /* returns: total PCM length (samples) of content if i==-1 PCM length 1175 (samples) of that logical bitstream for i==0 to n 1176 OV_EINVAL if the stream is not seekable (we can't know the 1177 length) or only partially open 1178 */ 1179 ogg_int64_t ov_pcm_total(OggVorbis_File *vf,int i){ 1180 if(vf->ready_state<OPENED)return(OV_EINVAL); 1181 if(!vf->seekable || i>=vf->links)return(OV_EINVAL); 1182 if(i<0){ 1183 ogg_int64_t acc=0; 1184 int i; 1185 for(i=0;i<vf->links;i++) 1186 acc+=ov_pcm_total(vf,i); 1187 return(acc); 1188 }else{ 1189 return(vf->pcmlengths[i*2+1]); 1190 } 1191 } 1192 1193 /* returns: total seconds of content if i==-1 1194 seconds in that logical bitstream for i==0 to n 1195 OV_EINVAL if the stream is not seekable (we can't know the 1196 length) or only partially open 1197 */ 1198 double ov_time_total(OggVorbis_File *vf,int i){ 1199 if(vf->ready_state<OPENED)return(OV_EINVAL); 1200 if(!vf->seekable || i>=vf->links)return(OV_EINVAL); 1201 if(i<0){ 1202 double acc=0; 1203 int i; 1204 for(i=0;i<vf->links;i++) 1205 acc+=ov_time_total(vf,i); 1206 return(acc); 1207 }else{ 1208 return((double)(vf->pcmlengths[i*2+1])/vf->vi[i].rate); 1209 } 1210 } 1211 1212 /* seek to an offset relative to the *compressed* data. This also 1213 scans packets to update the PCM cursor. It will cross a logical 1214 bitstream boundary, but only if it can't get any packets out of the 1215 tail of the bitstream we seek to (so no surprises). 1216 1217 returns zero on success, nonzero on failure */ 1218 1219 int ov_raw_seek(OggVorbis_File *vf,ogg_int64_t pos){ 1220 ogg_stream_state work_os; 1221 int ret; 1222 1223 if(vf->ready_state<OPENED)return(OV_EINVAL); 1224 if(!vf->seekable) 1225 return(OV_ENOSEEK); /* don't dump machine if we can't seek */ 1226 1227 if(pos<0 || pos>vf->end)return(OV_EINVAL); 1228 1229 /* don't yet clear out decoding machine (if it's initialized), in 1230 the case we're in the same link. Restart the decode lapping, and 1231 let _fetch_and_process_packet deal with a potential bitstream 1232 boundary */ 1233 vf->pcm_offset=-1; 1234 ogg_stream_reset_serialno(&vf->os, 1235 vf->current_serialno); /* must set serialno */ 1236 vorbis_synthesis_restart(&vf->vd); 1237 1238 ret=_seek_helper(vf,pos); 1239 if(ret)goto seek_error; 1240 1241 /* we need to make sure the pcm_offset is set, but we don't want to 1242 advance the raw cursor past good packets just to get to the first 1243 with a granulepos. That's not equivalent behavior to beginning 1244 decoding as immediately after the seek position as possible. 1245 1246 So, a hack. We use two stream states; a local scratch state and 1247 the shared vf->os stream state. We use the local state to 1248 scan, and the shared state as a buffer for later decode. 1249 1250 Unfortuantely, on the last page we still advance to last packet 1251 because the granulepos on the last page is not necessarily on a 1252 packet boundary, and we need to make sure the granpos is 1253 correct. 1254 */ 1255 1256 { 1257 ogg_page og; 1258 ogg_packet op; 1259 int lastblock=0; 1260 int accblock=0; 1261 int thisblock=0; 1262 int lastflag=0; 1263 int firstflag=0; 1264 ogg_int64_t pagepos=-1; 1265 1266 ogg_stream_init(&work_os,vf->current_serialno); /* get the memory ready */ 1267 ogg_stream_reset(&work_os); /* eliminate the spurious OV_HOLE 1268 return from not necessarily 1269 starting from the beginning */ 1270 1271 while(1){ 1272 if(vf->ready_state>=STREAMSET){ 1273 /* snarf/scan a packet if we can */ 1274 int result=ogg_stream_packetout(&work_os,&op); 1275 1276 if(result>0){ 1277 1278 if(vf->vi[vf->current_link].codec_setup){ 1279 thisblock=vorbis_packet_blocksize(vf->vi+vf->current_link,&op); 1280 if(thisblock<0){ 1281 ogg_stream_packetout(&vf->os,NULL); 1282 thisblock=0; 1283 }else{ 1284 1285 /* We can't get a guaranteed correct pcm position out of the 1286 last page in a stream because it might have a 'short' 1287 granpos, which can only be detected in the presence of a 1288 preceeding page. However, if the last page is also the first 1289 page, the granpos rules of a first page take precedence. Not 1290 only that, but for first==last, the EOS page must be treated 1291 as if its a normal first page for the stream to open/play. */ 1292 if(lastflag && !firstflag) 1293 ogg_stream_packetout(&vf->os,NULL); 1294 else 1295 if(lastblock)accblock+=(lastblock+thisblock)>>2; 1296 } 1297 1298 if(op.granulepos!=-1){ 1299 int i,link=vf->current_link; 1300 ogg_int64_t granulepos=op.granulepos-vf->pcmlengths[link*2]; 1301 if(granulepos<0)granulepos=0; 1302 1303 for(i=0;i<link;i++) 1304 granulepos+=vf->pcmlengths[i*2+1]; 1305 vf->pcm_offset=granulepos-accblock; 1306 if(vf->pcm_offset<0)vf->pcm_offset=0; 1307 break; 1308 } 1309 lastblock=thisblock; 1310 continue; 1311 }else 1312 ogg_stream_packetout(&vf->os,NULL); 1313 } 1314 } 1315 1316 if(!lastblock){ 1317 pagepos=_get_next_page(vf,&og,-1); 1318 if(pagepos<0){ 1319 vf->pcm_offset=ov_pcm_total(vf,-1); 1320 break; 1321 } 1322 }else{ 1323 /* huh? Bogus stream with packets but no granulepos */ 1324 vf->pcm_offset=-1; 1325 break; 1326 } 1327 1328 /* has our decoding just traversed a bitstream boundary? */ 1329 if(vf->ready_state>=STREAMSET){ 1330 if(vf->current_serialno!=ogg_page_serialno(&og)){ 1331 1332 /* two possibilities: 1333 1) our decoding just traversed a bitstream boundary 1334 2) another stream is multiplexed into this logical section? */ 1335 1336 if(ogg_page_bos(&og)){ 1337 /* we traversed */ 1338 _decode_clear(vf); /* clear out stream state */ 1339 ogg_stream_clear(&work_os); 1340 } /* else, do nothing; next loop will scoop another page */ 1341 } 1342 } 1343 1344 if(vf->ready_state<STREAMSET){ 1345 int link; 1346 long serialno = ogg_page_serialno(&og); 1347 1348 for(link=0;link<vf->links;link++) 1349 if(vf->serialnos[link]==serialno)break; 1350 1351 if(link==vf->links) continue; /* not the desired Vorbis 1352 bitstream section; keep 1353 trying */ 1354 vf->current_link=link; 1355 vf->current_serialno=serialno; 1356 ogg_stream_reset_serialno(&vf->os,serialno); 1357 ogg_stream_reset_serialno(&work_os,serialno); 1358 vf->ready_state=STREAMSET; 1359 firstflag=(pagepos<=vf->dataoffsets[link]); 1360 } 1361 1362 ogg_stream_pagein(&vf->os,&og); 1363 ogg_stream_pagein(&work_os,&og); 1364 lastflag=ogg_page_eos(&og); 1365 1366 } 1367 } 1368 1369 ogg_stream_clear(&work_os); 1370 vf->bittrack=0.f; 1371 vf->samptrack=0.f; 1372 return(0); 1373 1374 seek_error: 1375 /* dump the machine so we're in a known state */ 1376 vf->pcm_offset=-1; 1377 ogg_stream_clear(&work_os); 1378 _decode_clear(vf); 1379 return OV_EBADLINK; 1380 } 1381 1382 /* Page granularity seek (faster than sample granularity because we 1383 don't do the last bit of decode to find a specific sample). 1384 1385 Seek to the last [granule marked] page preceeding the specified pos 1386 location, such that decoding past the returned point will quickly 1387 arrive at the requested position. */ 1388 int ov_pcm_seek_page(OggVorbis_File *vf,ogg_int64_t pos){ 1389 int link=-1; 1390 ogg_int64_t result=0; 1391 ogg_int64_t total=ov_pcm_total(vf,-1); 1392 1393 if(vf->ready_state<OPENED)return(OV_EINVAL); 1394 if(!vf->seekable)return(OV_ENOSEEK); 1395 1396 if(pos<0 || pos>total)return(OV_EINVAL); 1397 1398 /* which bitstream section does this pcm offset occur in? */ 1399 for(link=vf->links-1;link>=0;link--){ 1400 total-=vf->pcmlengths[link*2+1]; 1401 if(pos>=total)break; 1402 } 1403 1404 /* search within the logical bitstream for the page with the highest 1405 pcm_pos preceeding (or equal to) pos. There is a danger here; 1406 missing pages or incorrect frame number information in the 1407 bitstream could make our task impossible. Account for that (it 1408 would be an error condition) */ 1409 1410 /* new search algorithm by HB (Nicholas Vinen) */ 1411 { 1412 ogg_int64_t end=vf->offsets[link+1]; 1413 ogg_int64_t begin=vf->offsets[link]; 1414 ogg_int64_t begintime = vf->pcmlengths[link*2]; 1415 ogg_int64_t endtime = vf->pcmlengths[link*2+1]+begintime; 1416 ogg_int64_t target=pos-total+begintime; 1417 ogg_int64_t best=begin; 1418 1419 ogg_page og; 1420 while(begin<end){ 1421 ogg_int64_t bisect; 1422 1423 if(end-begin<CHUNKSIZE){ 1424 bisect=begin; 1425 }else{ 1426 /* take a (pretty decent) guess. */ 1427 bisect=begin + 1428 (ogg_int64_t)((double)(target-begintime)*(end-begin)/(endtime-begintime)) 1429 - CHUNKSIZE; 1430 if(bisect<=begin) 1431 bisect=begin+1; 1432 } 1433 1434 result=_seek_helper(vf,bisect); 1435 if(result) goto seek_error; 1436 1437 while(begin<end){ 1438 result=_get_next_page(vf,&og,end-vf->offset); 1439 if(result==OV_EREAD) goto seek_error; 1440 if(result<0){ 1441 if(bisect<=begin+1) 1442 end=begin; /* found it */ 1443 else{ 1444 if(bisect==0) goto seek_error; 1445 bisect-=CHUNKSIZE; 1446 if(bisect<=begin)bisect=begin+1; 1447 result=_seek_helper(vf,bisect); 1448 if(result) goto seek_error; 1449 } 1450 }else{ 1451 ogg_int64_t granulepos; 1452 1453 if(ogg_page_serialno(&og)!=vf->serialnos[link]) 1454 continue; 1455 1456 granulepos=ogg_page_granulepos(&og); 1457 if(granulepos==-1)continue; 1458 1459 if(granulepos<target){ 1460 best=result; /* raw offset of packet with granulepos */ 1461 begin=vf->offset; /* raw offset of next page */ 1462 begintime=granulepos; 1463 1464 if(target-begintime>44100)break; 1465 bisect=begin; /* *not* begin + 1 */ 1466 }else{ 1467 if(bisect<=begin+1) 1468 end=begin; /* found it */ 1469 else{ 1470 if(end==vf->offset){ /* we're pretty close - we'd be stuck in */ 1471 end=result; 1472 bisect-=CHUNKSIZE; /* an endless loop otherwise. */ 1473 if(bisect<=begin)bisect=begin+1; 1474 result=_seek_helper(vf,bisect); 1475 if(result) goto seek_error; 1476 }else{ 1477 end=bisect; 1478 endtime=granulepos; 1479 break; 1480 } 1481 } 1482 } 1483 } 1484 } 1485 } 1486 1487 /* found our page. seek to it, update pcm offset. Easier case than 1488 raw_seek, don't keep packets preceeding granulepos. */ 1489 { 1490 ogg_page og; 1491 ogg_packet op; 1492 1493 /* seek */ 1494 result=_seek_helper(vf,best); 1495 vf->pcm_offset=-1; 1496 if(result) goto seek_error; 1497 result=_get_next_page(vf,&og,-1); 1498 if(result<0) goto seek_error; 1499 1500 if(link!=vf->current_link){ 1501 /* Different link; dump entire decode machine */ 1502 _decode_clear(vf); 1503 1504 vf->current_link=link; 1505 vf->current_serialno=vf->serialnos[link]; 1506 vf->ready_state=STREAMSET; 1507 1508 }else{ 1509 vorbis_synthesis_restart(&vf->vd); 1510 } 1511 1512 ogg_stream_reset_serialno(&vf->os,vf->current_serialno); 1513 ogg_stream_pagein(&vf->os,&og); 1514 1515 /* pull out all but last packet; the one with granulepos */ 1516 while(1){ 1517 result=ogg_stream_packetpeek(&vf->os,&op); 1518 if(result==0){ 1519 /* !!! the packet finishing this page originated on a 1520 preceeding page. Keep fetching previous pages until we 1521 get one with a granulepos or without the 'continued' flag 1522 set. Then just use raw_seek for simplicity. */ 1523 1524 result=_seek_helper(vf,best); 1525 if(result<0) goto seek_error; 1526 1527 while(1){ 1528 result=_get_prev_page(vf,&og); 1529 if(result<0) goto seek_error; 1530 if(ogg_page_serialno(&og)==vf->current_serialno && 1531 (ogg_page_granulepos(&og)>-1 || 1532 !ogg_page_continued(&og))){ 1533 return ov_raw_seek(vf,result); 1534 } 1535 vf->offset=result; 1536 } 1537 } 1538 if(result<0){ 1539 result = OV_EBADPACKET; 1540 goto seek_error; 1541 } 1542 if(op.granulepos!=-1){ 1543 vf->pcm_offset=op.granulepos-vf->pcmlengths[vf->current_link*2]; 1544 if(vf->pcm_offset<0)vf->pcm_offset=0; 1545 vf->pcm_offset+=total; 1546 break; 1547 }else 1548 result=ogg_stream_packetout(&vf->os,NULL); 1549 } 1550 } 1551 } 1552 1553 /* verify result */ 1554 if(vf->pcm_offset>pos || pos>ov_pcm_total(vf,-1)){ 1555 result=OV_EFAULT; 1556 goto seek_error; 1557 } 1558 vf->bittrack=0.f; 1559 vf->samptrack=0.f; 1560 return(0); 1561 1562 seek_error: 1563 /* dump machine so we're in a known state */ 1564 vf->pcm_offset=-1; 1565 _decode_clear(vf); 1566 return (int)result; 1567 } 1568 1569 /* seek to a sample offset relative to the decompressed pcm stream 1570 returns zero on success, nonzero on failure */ 1571 1572 int ov_pcm_seek(OggVorbis_File *vf,ogg_int64_t pos){ 1573 int thisblock,lastblock=0; 1574 int ret=ov_pcm_seek_page(vf,pos); 1575 if(ret<0)return(ret); 1576 if((ret=_make_decode_ready(vf)))return ret; 1577 1578 /* discard leading packets we don't need for the lapping of the 1579 position we want; don't decode them */ 1580 1581 while(1){ 1582 ogg_packet op; 1583 ogg_page og; 1584 1585 int ret=ogg_stream_packetpeek(&vf->os,&op); 1586 if(ret>0){ 1587 thisblock=vorbis_packet_blocksize(vf->vi+vf->current_link,&op); 1588 if(thisblock<0){ 1589 ogg_stream_packetout(&vf->os,NULL); 1590 continue; /* non audio packet */ 1591 } 1592 if(lastblock)vf->pcm_offset+=(lastblock+thisblock)>>2; 1593 1594 if(vf->pcm_offset+((thisblock+ 1595 vorbis_info_blocksize(vf->vi,1))>>2)>=pos)break; 1596 1597 /* remove the packet from packet queue and track its granulepos */ 1598 ogg_stream_packetout(&vf->os,NULL); 1599 vorbis_synthesis_trackonly(&vf->vb,&op); /* set up a vb with 1600 only tracking, no 1601 pcm_decode */ 1602 vorbis_synthesis_blockin(&vf->vd,&vf->vb); 1603 1604 /* end of logical stream case is hard, especially with exact 1605 length positioning. */ 1606 1607 if(op.granulepos>-1){ 1608 int i; 1609 /* always believe the stream markers */ 1610 vf->pcm_offset=op.granulepos-vf->pcmlengths[vf->current_link*2]; 1611 if(vf->pcm_offset<0)vf->pcm_offset=0; 1612 for(i=0;i<vf->current_link;i++) 1613 vf->pcm_offset+=vf->pcmlengths[i*2+1]; 1614 } 1615 1616 lastblock=thisblock; 1617 1618 }else{ 1619 if(ret<0 && ret!=OV_HOLE)break; 1620 1621 /* suck in a new page */ 1622 if(_get_next_page(vf,&og,-1)<0)break; 1623 if(ogg_page_bos(&og))_decode_clear(vf); 1624 1625 if(vf->ready_state<STREAMSET){ 1626 long serialno=ogg_page_serialno(&og); 1627 int link; 1628 1629 for(link=0;link<vf->links;link++) 1630 if(vf->serialnos[link]==serialno)break; 1631 if(link==vf->links) continue; 1632 vf->current_link=link; 1633 1634 vf->ready_state=STREAMSET; 1635 vf->current_serialno=ogg_page_serialno(&og); 1636 ogg_stream_reset_serialno(&vf->os,serialno); 1637 ret=_make_decode_ready(vf); 1638 if(ret)return ret; 1639 lastblock=0; 1640 } 1641 1642 ogg_stream_pagein(&vf->os,&og); 1643 } 1644 } 1645 1646 vf->bittrack=0.f; 1647 vf->samptrack=0.f; 1648 /* discard samples until we reach the desired position. Crossing a 1649 logical bitstream boundary with abandon is OK. */ 1650 while(vf->pcm_offset<pos){ 1651 ogg_int64_t target=pos-vf->pcm_offset; 1652 long samples=vorbis_synthesis_pcmout(&vf->vd,NULL); 1653 1654 if(samples>target)samples=target; 1655 vorbis_synthesis_read(&vf->vd,samples); 1656 vf->pcm_offset+=samples; 1657 1658 if(samples<target) 1659 if(_fetch_and_process_packet(vf,NULL,1,1)<=0) 1660 vf->pcm_offset=ov_pcm_total(vf,-1); /* eof */ 1661 } 1662 return 0; 1663 } 1664 1665 /* seek to a playback time relative to the decompressed pcm stream 1666 returns zero on success, nonzero on failure */ 1667 int ov_time_seek(OggVorbis_File *vf,double seconds){ 1668 /* translate time to PCM position and call ov_pcm_seek */ 1669 1670 int link=-1; 1671 ogg_int64_t pcm_total=0; 1672 double time_total=0.; 1673 1674 if(vf->ready_state<OPENED)return(OV_EINVAL); 1675 if(!vf->seekable)return(OV_ENOSEEK); 1676 if(seconds<0)return(OV_EINVAL); 1677 1678 /* which bitstream section does this time offset occur in? */ 1679 for(link=0;link<vf->links;link++){ 1680 double addsec = ov_time_total(vf,link); 1681 if(seconds<time_total+addsec)break; 1682 time_total+=addsec; 1683 pcm_total+=vf->pcmlengths[link*2+1]; 1684 } 1685 1686 if(link==vf->links)return(OV_EINVAL); 1687 1688 /* enough information to convert time offset to pcm offset */ 1689 { 1690 ogg_int64_t target=pcm_total+(seconds-time_total)*vf->vi[link].rate; 1691 return(ov_pcm_seek(vf,target)); 1692 } 1693 } 1694 1695 /* page-granularity version of ov_time_seek 1696 returns zero on success, nonzero on failure */ 1697 int ov_time_seek_page(OggVorbis_File *vf,double seconds){ 1698 /* translate time to PCM position and call ov_pcm_seek */ 1699 1700 int link=-1; 1701 ogg_int64_t pcm_total=0; 1702 double time_total=0.; 1703 1704 if(vf->ready_state<OPENED)return(OV_EINVAL); 1705 if(!vf->seekable)return(OV_ENOSEEK); 1706 if(seconds<0)return(OV_EINVAL); 1707 1708 /* which bitstream section does this time offset occur in? */ 1709 for(link=0;link<vf->links;link++){ 1710 double addsec = ov_time_total(vf,link); 1711 if(seconds<time_total+addsec)break; 1712 time_total+=addsec; 1713 pcm_total+=vf->pcmlengths[link*2+1]; 1714 } 1715 1716 if(link==vf->links)return(OV_EINVAL); 1717 1718 /* enough information to convert time offset to pcm offset */ 1719 { 1720 ogg_int64_t target=pcm_total+(seconds-time_total)*vf->vi[link].rate; 1721 return(ov_pcm_seek_page(vf,target)); 1722 } 1723 } 1724 1725 /* tell the current stream offset cursor. Note that seek followed by 1726 tell will likely not give the set offset due to caching */ 1727 ogg_int64_t ov_raw_tell(OggVorbis_File *vf){ 1728 if(vf->ready_state<OPENED)return(OV_EINVAL); 1729 return(vf->offset); 1730 } 1731 1732 /* return PCM offset (sample) of next PCM sample to be read */ 1733 ogg_int64_t ov_pcm_tell(OggVorbis_File *vf){ 1734 if(vf->ready_state<OPENED)return(OV_EINVAL); 1735 return(vf->pcm_offset); 1736 } 1737 1738 /* return time offset (seconds) of next PCM sample to be read */ 1739 double ov_time_tell(OggVorbis_File *vf){ 1740 int link=0; 1741 ogg_int64_t pcm_total=0; 1742 double time_total=0.f; 1743 1744 if(vf->ready_state<OPENED)return(OV_EINVAL); 1745 if(vf->seekable){ 1746 pcm_total=ov_pcm_total(vf,-1); 1747 time_total=ov_time_total(vf,-1); 1748 1749 /* which bitstream section does this time offset occur in? */ 1750 for(link=vf->links-1;link>=0;link--){ 1751 pcm_total-=vf->pcmlengths[link*2+1]; 1752 time_total-=ov_time_total(vf,link); 1753 if(vf->pcm_offset>=pcm_total)break; 1754 } 1755 } 1756 1757 return((double)time_total+(double)(vf->pcm_offset-pcm_total)/vf->vi[link].rate); 1758 } 1759 1760 /* link: -1) return the vorbis_info struct for the bitstream section 1761 currently being decoded 1762 0-n) to request information for a specific bitstream section 1763 1764 In the case of a non-seekable bitstream, any call returns the 1765 current bitstream. NULL in the case that the machine is not 1766 initialized */ 1767 1768 vorbis_info *ov_info(OggVorbis_File *vf,int link){ 1769 if(vf->seekable){ 1770 if(link<0) 1771 if(vf->ready_state>=STREAMSET) 1772 return vf->vi+vf->current_link; 1773 else 1774 return vf->vi; 1775 else 1776 if(link>=vf->links) 1777 return NULL; 1778 else 1779 return vf->vi+link; 1780 }else{ 1781 return vf->vi; 1782 } 1783 } 1784 1785 /* grr, strong typing, grr, no templates/inheritence, grr */ 1786 vorbis_comment *ov_comment(OggVorbis_File *vf,int link){ 1787 if(vf->seekable){ 1788 if(link<0) 1789 if(vf->ready_state>=STREAMSET) 1790 return vf->vc+vf->current_link; 1791 else 1792 return vf->vc; 1793 else 1794 if(link>=vf->links) 1795 return NULL; 1796 else 1797 return vf->vc+link; 1798 }else{ 1799 return vf->vc; 1800 } 1801 } 1802 1803 static int host_is_big_endian() { 1804 ogg_int32_t pattern = 0xfeedface; /* deadbeef */ 1805 unsigned char *bytewise = (unsigned char *)&pattern; 1806 if (bytewise[0] == 0xfe) return 1; 1807 return 0; 1808 } 1809 1810 /* up to this point, everything could more or less hide the multiple 1811 logical bitstream nature of chaining from the toplevel application 1812 if the toplevel application didn't particularly care. However, at 1813 the point that we actually read audio back, the multiple-section 1814 nature must surface: Multiple bitstream sections do not necessarily 1815 have to have the same number of channels or sampling rate. 1816 1817 ov_read returns the sequential logical bitstream number currently 1818 being decoded along with the PCM data in order that the toplevel 1819 application can take action on channel/sample rate changes. This 1820 number will be incremented even for streamed (non-seekable) streams 1821 (for seekable streams, it represents the actual logical bitstream 1822 index within the physical bitstream. Note that the accessor 1823 functions above are aware of this dichotomy). 1824 1825 ov_read_filter is exactly the same as ov_read except that it processes 1826 the decoded audio data through a filter before packing it into the 1827 requested format. This gives greater accuracy than applying a filter 1828 after the audio has been converted into integral PCM. 1829 1830 input values: buffer) a buffer to hold packed PCM data for return 1831 length) the byte length requested to be placed into buffer 1832 bigendianp) should the data be packed LSB first (0) or 1833 MSB first (1) 1834 word) word size for output. currently 1 (byte) or 1835 2 (16 bit short) 1836 1837 return values: <0) error/hole in data (OV_HOLE), partial open (OV_EINVAL) 1838 0) EOF 1839 n) number of bytes of PCM actually returned. The 1840 below works on a packet-by-packet basis, so the 1841 return length is not related to the 'length' passed 1842 in, just guaranteed to fit. 1843 1844 *section) set to the logical bitstream number */ 1845 1846 long ov_read_filter(OggVorbis_File *vf,char *buffer,int length, 1847 int bigendianp,int word,int sgned,int *bitstream, 1848 void (*filter)(float **pcm,long channels,long samples,void *filter_param),void *filter_param){ 1849 int i,j; 1850 int host_endian = host_is_big_endian(); 1851 1852 float **pcm; 1853 long samples; 1854 1855 if(vf->ready_state<OPENED)return(OV_EINVAL); 1856 1857 while(1){ 1858 if(vf->ready_state==INITSET){ 1859 samples=vorbis_synthesis_pcmout(&vf->vd,&pcm); 1860 if(samples)break; 1861 } 1862 1863 /* suck in another packet */ 1864 { 1865 int ret=_fetch_and_process_packet(vf,NULL,1,1); 1866 if(ret==OV_EOF) 1867 return(0); 1868 if(ret<=0) 1869 return(ret); 1870 } 1871 1872 } 1873 1874 if(samples>0){ 1875 1876 /* yay! proceed to pack data into the byte buffer */ 1877 1878 long channels=ov_info(vf,-1)->channels; 1879 long bytespersample=word * channels; 1880 vorbis_fpu_control fpu; 1881 if(samples>length/bytespersample)samples=length/bytespersample; 1882 1883 if(samples <= 0) 1884 return OV_EINVAL; 1885 1886 /* Here. */ 1887 if(filter) 1888 filter(pcm,channels,samples,filter_param); 1889 1890 /* a tight loop to pack each size */ 1891 { 1892 int val; 1893 if(word==1){ 1894 int off=(sgned?0:128); 1895 vorbis_fpu_setround(&fpu); 1896 for(j=0;j<samples;j++) 1897 for(i=0;i<channels;i++){ 1898 val=vorbis_ftoi(pcm[i][j]*128.f); 1899 if(val>127)val=127; 1900 else if(val<-128)val=-128; 1901 *buffer++=val+off; 1902 } 1903 vorbis_fpu_restore(fpu); 1904 }else{ 1905 int off=(sgned?0:32768); 1906 1907 if(host_endian==bigendianp){ 1908 if(sgned){ 1909 1910 vorbis_fpu_setround(&fpu); 1911 for(i=0;i<channels;i++) { /* It's faster in this order */ 1912 float *src=pcm[i]; 1913 short *dest=((short *)buffer)+i; 1914 for(j=0;j<samples;j++) { 1915 val=vorbis_ftoi(src[j]*32768.f); 1916 if(val>32767)val=32767; 1917 else if(val<-32768)val=-32768; 1918 *dest=val; 1919 dest+=channels; 1920 } 1921 } 1922 vorbis_fpu_restore(fpu); 1923 1924 }else{ 1925 1926 vorbis_fpu_setround(&fpu); 1927 for(i=0;i<channels;i++) { 1928 float *src=pcm[i]; 1929 short *dest=((short *)buffer)+i; 1930 for(j=0;j<samples;j++) { 1931 val=vorbis_ftoi(src[j]*32768.f); 1932 if(val>32767)val=32767; 1933 else if(val<-32768)val=-32768; 1934 *dest=val+off; 1935 dest+=channels; 1936 } 1937 } 1938 vorbis_fpu_restore(fpu); 1939 1940 } 1941 }else if(bigendianp){ 1942 1943 vorbis_fpu_setround(&fpu); 1944 for(j=0;j<samples;j++) 1945 for(i=0;i<channels;i++){ 1946 val=vorbis_ftoi(pcm[i][j]*32768.f); 1947 if(val>32767)val=32767; 1948 else if(val<-32768)val=-32768; 1949 val+=off; 1950 *buffer++=(val>>8); 1951 *buffer++=(val&0xff); 1952 } 1953 vorbis_fpu_restore(fpu); 1954 1955 }else{ 1956 int val; 1957 vorbis_fpu_setround(&fpu); 1958 for(j=0;j<samples;j++) 1959 for(i=0;i<channels;i++){ 1960 val=vorbis_ftoi(pcm[i][j]*32768.f); 1961 if(val>32767)val=32767; 1962 else if(val<-32768)val=-32768; 1963 val+=off; 1964 *buffer++=(val&0xff); 1965 *buffer++=(val>>8); 1966 } 1967 vorbis_fpu_restore(fpu); 1968 1969 } 1970 } 1971 } 1972 1973 vorbis_synthesis_read(&vf->vd,samples); 1974 vf->pcm_offset+=samples; 1975 if(bitstream)*bitstream=vf->current_link; 1976 return(samples*bytespersample); 1977 }else{ 1978 return(samples); 1979 } 1980 } 1981 1982 long ov_read(OggVorbis_File *vf,char *buffer,int length, 1983 int bigendianp,int word,int sgned,int *bitstream){ 1984 return ov_read_filter(vf, buffer, length, bigendianp, word, sgned, bitstream, NULL, NULL); 1985 } 1986 1987 /* input values: pcm_channels) a float vector per channel of output 1988 length) the sample length being read by the app 1989 1990 return values: <0) error/hole in data (OV_HOLE), partial open (OV_EINVAL) 1991 0) EOF 1992 n) number of samples of PCM actually returned. The 1993 below works on a packet-by-packet basis, so the 1994 return length is not related to the 'length' passed 1995 in, just guaranteed to fit. 1996 1997 *section) set to the logical bitstream number */ 1998 1999 2000 2001 long ov_read_float(OggVorbis_File *vf,float ***pcm_channels,int length, 2002 int *bitstream){ 2003 2004 if(vf->ready_state<OPENED)return(OV_EINVAL); 2005 2006 while(1){ 2007 if(vf->ready_state==INITSET){ 2008 float **pcm; 2009 long samples=vorbis_synthesis_pcmout(&vf->vd,&pcm); 2010 if(samples){ 2011 if(pcm_channels)*pcm_channels=pcm; 2012 if(samples>length)samples=length; 2013 vorbis_synthesis_read(&vf->vd,samples); 2014 vf->pcm_offset+=samples; 2015 if(bitstream)*bitstream=vf->current_link; 2016 return samples; 2017 2018 } 2019 } 2020 2021 /* suck in another packet */ 2022 { 2023 int ret=_fetch_and_process_packet(vf,NULL,1,1); 2024 if(ret==OV_EOF)return(0); 2025 if(ret<=0)return(ret); 2026 } 2027 2028 } 2029 } 2030 2031 extern float *vorbis_window(vorbis_dsp_state *v,int W); 2032 2033 static void _ov_splice(float **pcm,float **lappcm, 2034 int n1, int n2, 2035 int ch1, int ch2, 2036 float *w1, float *w2){ 2037 int i,j; 2038 float *w=w1; 2039 int n=n1; 2040 2041 if(n1>n2){ 2042 n=n2; 2043 w=w2; 2044 } 2045 2046 /* splice */ 2047 for(j=0;j<ch1 && j<ch2;j++){ 2048 float *s=lappcm[j]; 2049 float *d=pcm[j]; 2050 2051 for(i=0;i<n;i++){ 2052 float wd=w[i]*w[i]; 2053 float ws=1.-wd; 2054 d[i]=d[i]*wd + s[i]*ws; 2055 } 2056 } 2057 /* window from zero */ 2058 for(;j<ch2;j++){ 2059 float *d=pcm[j]; 2060 for(i=0;i<n;i++){ 2061 float wd=w[i]*w[i]; 2062 d[i]=d[i]*wd; 2063 } 2064 } 2065 2066 } 2067 2068 /* make sure vf is INITSET */ 2069 static int _ov_initset(OggVorbis_File *vf){ 2070 while(1){ 2071 if(vf->ready_state==INITSET)break; 2072 /* suck in another packet */ 2073 { 2074 int ret=_fetch_and_process_packet(vf,NULL,1,0); 2075 if(ret<0 && ret!=OV_HOLE)return(ret); 2076 } 2077 } 2078 return 0; 2079 } 2080 2081 /* make sure vf is INITSET and that we have a primed buffer; if 2082 we're crosslapping at a stream section boundary, this also makes 2083 sure we're sanity checking against the right stream information */ 2084 static int _ov_initprime(OggVorbis_File *vf){ 2085 vorbis_dsp_state *vd=&vf->vd; 2086 while(1){ 2087 if(vf->ready_state==INITSET) 2088 if(vorbis_synthesis_pcmout(vd,NULL))break; 2089 2090 /* suck in another packet */ 2091 { 2092 int ret=_fetch_and_process_packet(vf,NULL,1,0); 2093 if(ret<0 && ret!=OV_HOLE)return(ret); 2094 } 2095 } 2096 return 0; 2097 } 2098 2099 /* grab enough data for lapping from vf; this may be in the form of 2100 unreturned, already-decoded pcm, remaining PCM we will need to 2101 decode, or synthetic postextrapolation from last packets. */ 2102 static void _ov_getlap(OggVorbis_File *vf,vorbis_info *vi,vorbis_dsp_state *vd, 2103 float **lappcm,int lapsize){ 2104 int lapcount=0,i; 2105 float **pcm; 2106 2107 /* try first to decode the lapping data */ 2108 while(lapcount<lapsize){ 2109 int samples=vorbis_synthesis_pcmout(vd,&pcm); 2110 if(samples){ 2111 if(samples>lapsize-lapcount)samples=lapsize-lapcount; 2112 for(i=0;i<vi->channels;i++) 2113 memcpy(lappcm[i]+lapcount,pcm[i],sizeof(**pcm)*samples); 2114 lapcount+=samples; 2115 vorbis_synthesis_read(vd,samples); 2116 }else{ 2117 /* suck in another packet */ 2118 int ret=_fetch_and_process_packet(vf,NULL,1,0); /* do *not* span */ 2119 if(ret==OV_EOF)break; 2120 } 2121 } 2122 if(lapcount<lapsize){ 2123 /* failed to get lapping data from normal decode; pry it from the 2124 postextrapolation buffering, or the second half of the MDCT 2125 from the last packet */ 2126 int samples=vorbis_synthesis_lapout(&vf->vd,&pcm); 2127 if(samples==0){ 2128 for(i=0;i<vi->channels;i++) 2129 memset(lappcm[i]+lapcount,0,sizeof(**pcm)*lapsize-lapcount); 2130 lapcount=lapsize; 2131 }else{ 2132 if(samples>lapsize-lapcount)samples=lapsize-lapcount; 2133 for(i=0;i<vi->channels;i++) 2134 memcpy(lappcm[i]+lapcount,pcm[i],sizeof(**pcm)*samples); 2135 lapcount+=samples; 2136 } 2137 } 2138 } 2139 2140 /* this sets up crosslapping of a sample by using trailing data from 2141 sample 1 and lapping it into the windowing buffer of sample 2 */ 2142 int ov_crosslap(OggVorbis_File *vf1, OggVorbis_File *vf2){ 2143 vorbis_info *vi1,*vi2; 2144 float **lappcm; 2145 float **pcm; 2146 float *w1,*w2; 2147 int n1,n2,i,ret,hs1,hs2; 2148 2149 if(vf1==vf2)return(0); /* degenerate case */ 2150 if(vf1->ready_state<OPENED)return(OV_EINVAL); 2151 if(vf2->ready_state<OPENED)return(OV_EINVAL); 2152 2153 /* the relevant overlap buffers must be pre-checked and pre-primed 2154 before looking at settings in the event that priming would cross 2155 a bitstream boundary. So, do it now */ 2156 2157 ret=_ov_initset(vf1); 2158 if(ret)return(ret); 2159 ret=_ov_initprime(vf2); 2160 if(ret)return(ret); 2161 2162 vi1=ov_info(vf1,-1); 2163 vi2=ov_info(vf2,-1); 2164 hs1=ov_halfrate_p(vf1); 2165 hs2=ov_halfrate_p(vf2); 2166 2167 lappcm=alloca(sizeof(*lappcm)*vi1->channels); 2168 n1=vorbis_info_blocksize(vi1,0)>>(1+hs1); 2169 n2=vorbis_info_blocksize(vi2,0)>>(1+hs2); 2170 w1=vorbis_window(&vf1->vd,0); 2171 w2=vorbis_window(&vf2->vd,0); 2172 2173 for(i=0;i<vi1->channels;i++) 2174 lappcm[i]=alloca(sizeof(**lappcm)*n1); 2175 2176 _ov_getlap(vf1,vi1,&vf1->vd,lappcm,n1); 2177 2178 /* have a lapping buffer from vf1; now to splice it into the lapping 2179 buffer of vf2 */ 2180 /* consolidate and expose the buffer. */ 2181 vorbis_synthesis_lapout(&vf2->vd,&pcm); 2182 2183 #if 0 2184 _analysis_output_always("pcmL",0,pcm[0],n1*2,0,0,0); 2185 _analysis_output_always("pcmR",0,pcm[1],n1*2,0,0,0); 2186 #endif 2187 2188 /* splice */ 2189 _ov_splice(pcm,lappcm,n1,n2,vi1->channels,vi2->channels,w1,w2); 2190 2191 /* done */ 2192 return(0); 2193 } 2194 2195 static int _ov_64_seek_lap(OggVorbis_File *vf,ogg_int64_t pos, 2196 int (*localseek)(OggVorbis_File *,ogg_int64_t)){ 2197 vorbis_info *vi; 2198 float **lappcm; 2199 float **pcm; 2200 float *w1,*w2; 2201 int n1,n2,ch1,ch2,hs; 2202 int i,ret; 2203 2204 if(vf->ready_state<OPENED)return(OV_EINVAL); 2205 ret=_ov_initset(vf); 2206 if(ret)return(ret); 2207 vi=ov_info(vf,-1); 2208 hs=ov_halfrate_p(vf); 2209 2210 ch1=vi->channels; 2211 n1=vorbis_info_blocksize(vi,0)>>(1+hs); 2212 w1=vorbis_window(&vf->vd,0); /* window arrays from libvorbis are 2213 persistent; even if the decode state 2214 from this link gets dumped, this 2215 window array continues to exist */ 2216 2217 lappcm=alloca(sizeof(*lappcm)*ch1); 2218 for(i=0;i<ch1;i++) 2219 lappcm[i]=alloca(sizeof(**lappcm)*n1); 2220 _ov_getlap(vf,vi,&vf->vd,lappcm,n1); 2221 2222 /* have lapping data; seek and prime the buffer */ 2223 ret=localseek(vf,pos); 2224 if(ret)return ret; 2225 ret=_ov_initprime(vf); 2226 if(ret)return(ret); 2227 2228 /* Guard against cross-link changes; they're perfectly legal */ 2229 vi=ov_info(vf,-1); 2230 ch2=vi->channels; 2231 n2=vorbis_info_blocksize(vi,0)>>(1+hs); 2232 w2=vorbis_window(&vf->vd,0); 2233 2234 /* consolidate and expose the buffer. */ 2235 vorbis_synthesis_lapout(&vf->vd,&pcm); 2236 2237 /* splice */ 2238 _ov_splice(pcm,lappcm,n1,n2,ch1,ch2,w1,w2); 2239 2240 /* done */ 2241 return(0); 2242 } 2243 2244 int ov_raw_seek_lap(OggVorbis_File *vf,ogg_int64_t pos){ 2245 return _ov_64_seek_lap(vf,pos,ov_raw_seek); 2246 } 2247 2248 int ov_pcm_seek_lap(OggVorbis_File *vf,ogg_int64_t pos){ 2249 return _ov_64_seek_lap(vf,pos,ov_pcm_seek); 2250 } 2251 2252 int ov_pcm_seek_page_lap(OggVorbis_File *vf,ogg_int64_t pos){ 2253 return _ov_64_seek_lap(vf,pos,ov_pcm_seek_page); 2254 } 2255 2256 static int _ov_d_seek_lap(OggVorbis_File *vf,double pos, 2257 int (*localseek)(OggVorbis_File *,double)){ 2258 vorbis_info *vi; 2259 float **lappcm; 2260 float **pcm; 2261 float *w1,*w2; 2262 int n1,n2,ch1,ch2,hs; 2263 int i,ret; 2264 2265 if(vf->ready_state<OPENED)return(OV_EINVAL); 2266 ret=_ov_initset(vf); 2267 if(ret)return(ret); 2268 vi=ov_info(vf,-1); 2269 hs=ov_halfrate_p(vf); 2270 2271 ch1=vi->channels; 2272 n1=vorbis_info_blocksize(vi,0)>>(1+hs); 2273 w1=vorbis_window(&vf->vd,0); /* window arrays from libvorbis are 2274 persistent; even if the decode state 2275 from this link gets dumped, this 2276 window array continues to exist */ 2277 2278 lappcm=alloca(sizeof(*lappcm)*ch1); 2279 for(i=0;i<ch1;i++) 2280 lappcm[i]=alloca(sizeof(**lappcm)*n1); 2281 _ov_getlap(vf,vi,&vf->vd,lappcm,n1); 2282 2283 /* have lapping data; seek and prime the buffer */ 2284 ret=localseek(vf,pos); 2285 if(ret)return ret; 2286 ret=_ov_initprime(vf); 2287 if(ret)return(ret); 2288 2289 /* Guard against cross-link changes; they're perfectly legal */ 2290 vi=ov_info(vf,-1); 2291 ch2=vi->channels; 2292 n2=vorbis_info_blocksize(vi,0)>>(1+hs); 2293 w2=vorbis_window(&vf->vd,0); 2294 2295 /* consolidate and expose the buffer. */ 2296 vorbis_synthesis_lapout(&vf->vd,&pcm); 2297 2298 /* splice */ 2299 _ov_splice(pcm,lappcm,n1,n2,ch1,ch2,w1,w2); 2300 2301 /* done */ 2302 return(0); 2303 } 2304 2305 int ov_time_seek_lap(OggVorbis_File *vf,double pos){ 2306 return _ov_d_seek_lap(vf,pos,ov_time_seek); 2307 } 2308 2309 int ov_time_seek_page_lap(OggVorbis_File *vf,double pos){ 2310 return _ov_d_seek_lap(vf,pos,ov_time_seek_page); 2311 } 2312
