1 /********************************************************************
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. *
8 * THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2009 *
9 * by the Xiph.Org Foundation http://www.xiph.org/ *
11 ********************************************************************
13 function: stdio-based convenience library for opening/seeking/decoding
16 ********************************************************************/
24 #include "vorbis/codec.h"
26 /* we don't need or want the static callback symbols here */
27 #define OV_EXCLUDE_STATIC_CALLBACKS
28 #include "vorbis/vorbisfile.h"
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) */
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. */
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. */
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. */
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 */
62 /* read a little more data from the file/pipe into the ogg_sync framer
64 #define CHUNKSIZE 65536 /* greater-than-page-size granularity seeking */
65 #define READSIZE 2048 /* a smaller read size is needed for low-rate streaming. */
67 static long _get_data(OggVorbis_File *vf){
69 if(!(vf->callbacks.read_func))return(-1);
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);
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){
83 if(!(vf->callbacks.seek_func)||
84 (vf->callbacks.seek_func)(vf->datasource, offset, SEEK_SET) == -1)
87 ogg_sync_reset(&vf->oy);
89 /* shouldn't happen unless someone writes a broken callback */
95 /* The read/seek functions track absolute position within the stream */
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.
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
105 return: <0) did not find a page (OV_FALSE, OV_EOF, OV_EREAD)
106 n) found a page at absolute offset n */
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;
114 if(boundary>0 && vf->offset>=boundary)return(OV_FALSE);
115 more=ogg_sync_pageseek(&vf->oy,og);
118 /* skipped n bytes */
122 /* send more paramedics */
123 if(!boundary)return(OV_FALSE);
125 long ret=_get_data(vf);
126 if(ret==0)return(OV_EOF);
127 if(ret<0)return(OV_EREAD);
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;
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
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;
150 ogg_int64_t offset=-1;
157 ret=_seek_helper(vf,begin);
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);
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);
179 ret=_get_next_page(vf,og,CHUNKSIZE);
181 /* this shouldn't be possible */
188 static void _add_serialno(ogg_page *og,long **serialno_list, int *n){
189 long s = ogg_page_serialno(og);
193 *serialno_list = _ogg_realloc(*serialno_list, sizeof(**serialno_list)*(*n));
195 *serialno_list = _ogg_malloc(sizeof(**serialno_list));
198 (*serialno_list)[(*n)-1] = s;
201 /* returns nonzero if found */
202 static int _lookup_serialno(long s, long *serialno_list, int n){
205 if(*serialno_list == s) return 1;
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);
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){
227 ogg_int64_t begin=vf->offset;
228 ogg_int64_t end=begin;
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;
241 ret=_seek_helper(vf,begin);
244 while(vf->offset<end){
245 ret=_get_next_page(vf,&og,end-vf->offset);
246 if(ret==OV_EREAD)return(OV_EREAD);
250 ret_serialno=ogg_page_serialno(&og);
251 ret_gran=ogg_page_granulepos(&og);
254 if(ret_serialno == *serialno){
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. */
270 /* we're not interested in the page... just the serialno and granpos. */
271 if(prefoffset>=0)return(prefoffset);
273 *serialno = ret_serialno;
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,
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);
296 vorbis_info_init(vi);
297 vorbis_comment_init(vc);
298 vf->ready_state=OPENED;
300 /* extract the serialnos of all BOS pages + the first set of vorbis
301 headers we see in the link */
303 while(ogg_page_bos(og_ptr)){
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);
314 _add_serialno(og_ptr,serialno_list,serialno_n);
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);
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))){
336 ogg_int64_t llret=_get_next_page(vf,og_ptr,CHUNKSIZE);
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);
355 if(vf->ready_state!=STREAMSET){
363 while(i<2){ /* get a page loop */
365 while(i<2){ /* get a packet loop */
367 int result=ogg_stream_packetout(&vf->os,&op);
374 if((ret=vorbis_synthesis_headerin(vi,vc,&op)))
381 if(_get_next_page(vf,og_ptr,CHUNKSIZE)<0){
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);
392 /* if we never see the final vorbis headers before the link
394 if(ogg_page_bos(og_ptr)){
402 /* otherwise, keep looking */
410 vorbis_info_clear(vi);
411 vorbis_comment_clear(vc);
412 vf->ready_state=OPENED;
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
421 static ogg_int64_t _initial_pcmoffset(OggVorbis_File *vf, vorbis_info *vi){
423 ogg_int64_t accumulated=0;
426 int serialno = vf->os.serialno;
430 if(_get_next_page(vf,&og,-1)<0)
431 break; /* should not be possible unless the file is truncated/mangled */
433 if(ogg_page_bos(&og)) break;
434 if(ogg_page_serialno(&og)!=serialno) continue;
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);
442 accumulated+=(lastblock+thisblock)>>2;
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;
454 /* less than zero? Either a corrupt file or a stream with samples
455 trimmed off the beginning, a normal occurrence; in both cases set
456 the offset to zero */
457 if(accumulated<0)accumulated=0;
462 /* finds each bitstream link one at a time using a bisection search
463 (has to begin by knowing the offset of the lb's initial page).
464 Recurses for each link so it can alloc the link storage after
465 finding them all, then unroll and fill the cache at the same time */
466 static int _bisect_forward_serialno(OggVorbis_File *vf,
468 ogg_int64_t searched,
472 long *currentno_list,
475 ogg_int64_t pcmoffset;
476 ogg_int64_t dataoffset=searched;
477 ogg_int64_t endsearched=end;
478 ogg_int64_t next=end;
479 ogg_int64_t searchgran=-1;
481 ogg_int64_t ret,last;
482 int serialno = vf->os.serialno;
485 we have the headers and serialnos for the link beginning at 'begin'
486 we have the offset and granpos of the last page in the file (potentially
487 not a page we care about)
490 /* Is the last page in our list of current serialnumbers? */
491 if(_lookup_serialno(endserial,currentno_list,currentnos)){
493 /* last page is in the starting serialno list, so we've bisected
494 down to (or just started with) a single link. Now we need to
495 find the last vorbis page belonging to the first vorbis stream
498 while(endserial != serialno){
499 endserial = serialno;
500 vf->offset=_get_prev_page_serial(vf,currentno_list,currentnos,&endserial,&endgran);
504 if(vf->offsets)_ogg_free(vf->offsets);
505 if(vf->serialnos)_ogg_free(vf->serialnos);
506 if(vf->dataoffsets)_ogg_free(vf->dataoffsets);
508 vf->offsets=_ogg_malloc((vf->links+1)*sizeof(*vf->offsets));
509 vf->vi=_ogg_realloc(vf->vi,vf->links*sizeof(*vf->vi));
510 vf->vc=_ogg_realloc(vf->vc,vf->links*sizeof(*vf->vc));
511 vf->serialnos=_ogg_malloc(vf->links*sizeof(*vf->serialnos));
512 vf->dataoffsets=_ogg_malloc(vf->links*sizeof(*vf->dataoffsets));
513 vf->pcmlengths=_ogg_malloc(vf->links*2*sizeof(*vf->pcmlengths));
515 vf->offsets[m+1]=end;
516 vf->offsets[m]=begin;
517 vf->pcmlengths[m*2+1]=(endgran<0?0:endgran);
521 long *next_serialno_list=NULL;
522 int next_serialnos=0;
526 /* the below guards against garbage seperating the last and
527 first pages of two links. */
528 while(searched<endsearched){
531 if(endsearched-searched<CHUNKSIZE){
534 bisect=(searched+endsearched)/2;
537 if(bisect != vf->offset){
538 ret=_seek_helper(vf,bisect);
542 last=_get_next_page(vf,&og,-1);
543 if(last==OV_EREAD)return(OV_EREAD);
544 if(last<0 || !_lookup_page_serialno(&og,currentno_list,currentnos)){
546 if(last>=0)next=last;
552 /* Bisection point found */
554 /* for the time being, fetch end PCM offset the simple way */
556 int testserial = serialno+1;
558 while(testserial != serialno){
559 testserial = serialno;
560 vf->offset=_get_prev_page_serial(vf,currentno_list,currentnos,&testserial,&searchgran);
564 if(vf->offset!=next){
565 ret=_seek_helper(vf,next);
569 ret=_fetch_headers(vf,&vi,&vc,&next_serialno_list,&next_serialnos,NULL);
571 serialno = vf->os.serialno;
572 dataoffset = vf->offset;
574 /* this will consume a page, however the next bistection always
575 starts with a raw seek */
576 pcmoffset = _initial_pcmoffset(vf,&vi);
578 ret=_bisect_forward_serialno(vf,next,vf->offset,end,endgran,endserial,
579 next_serialno_list,next_serialnos,m+1);
582 if(next_serialno_list)_ogg_free(next_serialno_list);
584 vf->offsets[m+1]=next;
585 vf->serialnos[m+1]=serialno;
586 vf->dataoffsets[m+1]=dataoffset;
591 vf->pcmlengths[m*2+1]=searchgran;
592 vf->pcmlengths[m*2+2]=pcmoffset;
593 vf->pcmlengths[m*2+3]-=pcmoffset;
594 if(vf->pcmlengths[m*2+3]<0)vf->pcmlengths[m*2+3]=0;
599 static int _make_decode_ready(OggVorbis_File *vf){
600 if(vf->ready_state>STREAMSET)return 0;
601 if(vf->ready_state<STREAMSET)return OV_EFAULT;
603 if(vorbis_synthesis_init(&vf->vd,vf->vi+vf->current_link))
606 if(vorbis_synthesis_init(&vf->vd,vf->vi))
609 vorbis_block_init(&vf->vd,&vf->vb);
610 vf->ready_state=INITSET;
616 static int _open_seekable2(OggVorbis_File *vf){
617 ogg_int64_t dataoffset=vf->dataoffsets[0],end,endgran=-1;
618 int endserial=vf->os.serialno;
619 int serialno=vf->os.serialno;
621 /* we're partially open and have a first link header state in
624 /* fetch initial PCM offset */
625 ogg_int64_t pcmoffset = _initial_pcmoffset(vf,vf->vi);
627 /* we can seek, so set out learning all about this file */
628 if(vf->callbacks.seek_func && vf->callbacks.tell_func){
629 (vf->callbacks.seek_func)(vf->datasource,0,SEEK_END);
630 vf->offset=vf->end=(vf->callbacks.tell_func)(vf->datasource);
632 vf->offset=vf->end=-1;
635 /* If seek_func is implemented, tell_func must also be implemented */
636 if(vf->end==-1) return(OV_EINVAL);
638 /* Get the offset of the last page of the physical bitstream, or, if
639 we're lucky the last vorbis page of this link as most OggVorbis
640 files will contain a single logical bitstream */
641 end=_get_prev_page_serial(vf,vf->serialnos+2,vf->serialnos[1],&endserial,&endgran);
642 if(end<0)return(end);
644 /* now determine bitstream structure recursively */
645 if(_bisect_forward_serialno(vf,0,dataoffset,vf->offset,endgran,endserial,
646 vf->serialnos+2,vf->serialnos[1],0)<0)return(OV_EREAD);
649 vf->serialnos[0]=serialno;
650 vf->dataoffsets[0]=dataoffset;
651 vf->pcmlengths[0]=pcmoffset;
652 vf->pcmlengths[1]-=pcmoffset;
653 if(vf->pcmlengths[1]<0)vf->pcmlengths[1]=0;
655 return(ov_raw_seek(vf,dataoffset));
658 /* clear out the current logical bitstream decoder */
659 static void _decode_clear(OggVorbis_File *vf){
660 vorbis_dsp_clear(&vf->vd);
661 vorbis_block_clear(&vf->vb);
662 vf->ready_state=OPENED;
665 /* fetch and process a packet. Handles the case where we're at a
666 bitstream boundary and dumps the decoding machine. If the decoding
667 machine is unloaded, it loads it. It also keeps pcm_offset up to
668 date (seek and read both use this. seek uses a special hack with
671 return: <0) error, OV_HOLE (lost packet) or OV_EOF
672 0) need more data (only if readp==0)
676 static int _fetch_and_process_packet(OggVorbis_File *vf,
682 /* handle one packet. Try to fetch it from current stream state */
683 /* extract packets from page */
686 if(vf->ready_state==STREAMSET){
687 int ret=_make_decode_ready(vf);
691 /* process a packet if we can. */
693 if(vf->ready_state==INITSET){
694 int hs=vorbis_synthesis_halfrate_p(vf->vi);
698 ogg_packet *op_ptr=(op_in?op_in:&op);
699 int result=ogg_stream_packetout(&vf->os,op_ptr);
700 ogg_int64_t granulepos;
703 if(result==-1)return(OV_HOLE); /* hole in the data. */
705 /* got a packet. process it */
706 granulepos=op_ptr->granulepos;
707 if(!vorbis_synthesis(&vf->vb,op_ptr)){ /* lazy check for lazy
709 header packets aren't
712 vorbis_synthesis will
715 /* suck in the synthesis data and track bitrate */
717 int oldsamples=vorbis_synthesis_pcmout(&vf->vd,NULL);
718 /* for proper use of libvorbis within libvorbisfile,
719 oldsamples will always be zero. */
720 if(oldsamples)return(OV_EFAULT);
722 vorbis_synthesis_blockin(&vf->vd,&vf->vb);
723 vf->samptrack+=(vorbis_synthesis_pcmout(&vf->vd,NULL)<<hs);
724 vf->bittrack+=op_ptr->bytes*8;
727 /* update the pcm offset. */
728 if(granulepos!=-1 && !op_ptr->e_o_s){
729 int link=(vf->seekable?vf->current_link:0);
732 /* this packet has a pcm_offset on it (the last packet
733 completed on a page carries the offset) After processing
734 (above), we know the pcm position of the *last* sample
735 ready to be returned. Find the offset of the *first*
737 As an aside, this trick is inaccurate if we begin
738 reading anew right at the last page; the end-of-stream
739 granulepos declares the last frame in the stream, and the
740 last packet of the last page may be a partial frame.
741 So, we need a previous granulepos from an in-sequence page
742 to have a reference point. Thus the !op_ptr->e_o_s clause
745 if(vf->seekable && link>0)
746 granulepos-=vf->pcmlengths[link*2];
747 if(granulepos<0)granulepos=0; /* actually, this
748 shouldn't be possible
749 here unless the stream
752 samples=(vorbis_synthesis_pcmout(&vf->vd,NULL)<<hs);
756 granulepos+=vf->pcmlengths[i*2+1];
757 vf->pcm_offset=granulepos;
767 if(vf->ready_state>=OPENED){
771 /* the loop is not strictly necessary, but there's no sense in
772 doing the extra checks of the larger loop for the common
773 case in a multiplexed bistream where the page is simply
774 part of a different logical bitstream; keep reading until
775 we get one with the correct serialno */
778 if((ret=_get_next_page(vf,&og,-1))<0){
779 return(OV_EOF); /* eof. leave unitialized */
782 /* bitrate tracking; add the header's bytes here, the body bytes
783 are done by packet above */
784 vf->bittrack+=og.header_len*8;
786 if(vf->ready_state==INITSET){
787 if(vf->current_serialno!=ogg_page_serialno(&og)){
789 /* two possibilities:
790 1) our decoding just traversed a bitstream boundary
791 2) another stream is multiplexed into this logical section */
793 if(ogg_page_bos(&og)){
801 vorbis_info_clear(vf->vi);
802 vorbis_comment_clear(vf->vc);
807 continue; /* possibility #2 */
815 /* Do we need to load a new machine before submitting the page? */
816 /* This is different in the seekable and non-seekable cases.
818 In the seekable case, we already have all the header
819 information loaded and cached; we just initialize the machine
820 with it and continue on our merry way.
822 In the non-seekable (streaming) case, we'll only be at a
823 boundary if we just left the previous logical bitstream and
824 we're now nominally at the header of the next bitstream
827 if(vf->ready_state!=INITSET){
830 if(vf->ready_state<STREAMSET){
832 long serialno = ogg_page_serialno(&og);
834 /* match the serialno to bitstream section. We use this rather than
835 offset positions to avoid problems near logical bitstream
838 for(link=0;link<vf->links;link++)
839 if(vf->serialnos[link]==serialno)break;
841 if(link==vf->links) continue; /* not the desired Vorbis
842 bitstream section; keep
845 vf->current_serialno=serialno;
846 vf->current_link=link;
848 ogg_stream_reset_serialno(&vf->os,vf->current_serialno);
849 vf->ready_state=STREAMSET;
852 /* we're streaming */
853 /* fetch the three header packets, build the info struct */
855 int ret=_fetch_headers(vf,vf->vi,vf->vc,NULL,NULL,&og);
857 vf->current_serialno=vf->os.serialno;
864 /* the buffered page is the data we want, and we're ready for it;
865 add it to the stream state */
866 ogg_stream_pagein(&vf->os,&og);
871 /* if, eg, 64 bit stdio is configured by default, this will build with
873 static int _fseek64_wrap(FILE *f,ogg_int64_t off,int whence){
874 if(f==NULL)return(-1);
875 return fseek(f,off,whence);
878 static int _ov_open1(void *f,OggVorbis_File *vf,const char *initial,
879 long ibytes, ov_callbacks callbacks){
880 int offsettest=((f && callbacks.seek_func)?callbacks.seek_func(f,0,SEEK_CUR):-1);
881 long *serialno_list=NULL;
882 int serialno_list_size=0;
885 memset(vf,0,sizeof(*vf));
887 vf->callbacks = callbacks;
889 /* init the framing state */
890 ogg_sync_init(&vf->oy);
892 /* perhaps some data was previously read into a buffer for testing
893 against other stream types. Allow initialization from this
894 previously read data (especially as we may be reading from a
895 non-seekable stream) */
897 char *buffer=ogg_sync_buffer(&vf->oy,ibytes);
898 memcpy(buffer,initial,ibytes);
899 ogg_sync_wrote(&vf->oy,ibytes);
902 /* can we seek? Stevens suggests the seek test was portable */
903 if(offsettest!=-1)vf->seekable=1;
905 /* No seeking yet; Set up a 'single' (current) logical bitstream
906 entry for partial open */
908 vf->vi=_ogg_calloc(vf->links,sizeof(*vf->vi));
909 vf->vc=_ogg_calloc(vf->links,sizeof(*vf->vc));
910 ogg_stream_init(&vf->os,-1); /* fill in the serialno later */
912 /* Fetch all BOS pages, store the vorbis header and all seen serial
913 numbers, load subsequent vorbis setup headers */
914 if((ret=_fetch_headers(vf,vf->vi,vf->vc,&serialno_list,&serialno_list_size,NULL))<0){
918 /* serial number list for first link needs to be held somewhere
919 for second stage of seekable stream open; this saves having to
920 seek/reread first link's serialnumber data then. */
921 vf->serialnos=_ogg_calloc(serialno_list_size+2,sizeof(*vf->serialnos));
922 vf->serialnos[0]=vf->current_serialno=vf->os.serialno;
923 vf->serialnos[1]=serialno_list_size;
924 memcpy(vf->serialnos+2,serialno_list,serialno_list_size*sizeof(*vf->serialnos));
926 vf->offsets=_ogg_calloc(1,sizeof(*vf->offsets));
927 vf->dataoffsets=_ogg_calloc(1,sizeof(*vf->dataoffsets));
929 vf->dataoffsets[0]=vf->offset;
931 vf->ready_state=PARTOPEN;
933 if(serialno_list)_ogg_free(serialno_list);
937 static int _ov_open2(OggVorbis_File *vf){
938 if(vf->ready_state != PARTOPEN) return OV_EINVAL;
939 vf->ready_state=OPENED;
941 int ret=_open_seekable2(vf);
948 vf->ready_state=STREAMSET;
954 /* clear out the OggVorbis_File struct */
955 int ov_clear(OggVorbis_File *vf){
957 vorbis_block_clear(&vf->vb);
958 vorbis_dsp_clear(&vf->vd);
959 ogg_stream_clear(&vf->os);
961 if(vf->vi && vf->links){
963 for(i=0;i<vf->links;i++){
964 vorbis_info_clear(vf->vi+i);
965 vorbis_comment_clear(vf->vc+i);
970 if(vf->dataoffsets)_ogg_free(vf->dataoffsets);
971 if(vf->pcmlengths)_ogg_free(vf->pcmlengths);
972 if(vf->serialnos)_ogg_free(vf->serialnos);
973 if(vf->offsets)_ogg_free(vf->offsets);
974 ogg_sync_clear(&vf->oy);
975 if(vf->datasource && vf->callbacks.close_func)
976 (vf->callbacks.close_func)(vf->datasource);
977 memset(vf,0,sizeof(*vf));
985 /* inspects the OggVorbis file and finds/documents all the logical
986 bitstreams contained in it. Tries to be tolerant of logical
987 bitstream sections that are truncated/woogie.
993 int ov_open_callbacks(void *f,OggVorbis_File *vf,
994 const char *initial,long ibytes,ov_callbacks callbacks){
995 int ret=_ov_open1(f,vf,initial,ibytes,callbacks);
997 return _ov_open2(vf);
1000 int ov_open(FILE *f,OggVorbis_File *vf,const char *initial,long ibytes){
1001 ov_callbacks callbacks = {
1002 (size_t (*)(void *, size_t, size_t, void *)) fread,
1003 (int (*)(void *, ogg_int64_t, int)) _fseek64_wrap,
1004 (int (*)(void *)) fclose,
1005 (long (*)(void *)) ftell
1008 return ov_open_callbacks((void *)f, vf, initial, ibytes, callbacks);
1011 int ov_fopen(const char *path,OggVorbis_File *vf){
1013 FILE *f = fopen(path,"rb");
1016 ret = ov_open(f,vf,NULL,0);
1022 /* cheap hack for game usage where downsampling is desirable; there's
1023 no need for SRC as we can just do it cheaply in libvorbis. */
1025 int ov_halfrate(OggVorbis_File *vf,int flag){
1027 if(vf->vi==NULL)return OV_EINVAL;
1028 if(vf->ready_state>STREAMSET){
1029 /* clear out stream state; dumping the decode machine is needed to
1030 reinit the MDCT lookups. */
1031 vorbis_dsp_clear(&vf->vd);
1032 vorbis_block_clear(&vf->vb);
1033 vf->ready_state=STREAMSET;
1034 if(vf->pcm_offset>=0){
1035 ogg_int64_t pos=vf->pcm_offset;
1036 vf->pcm_offset=-1; /* make sure the pos is dumped if unseekable */
1037 ov_pcm_seek(vf,pos);
1041 for(i=0;i<vf->links;i++){
1042 if(vorbis_synthesis_halfrate(vf->vi+i,flag)){
1043 if(flag) ov_halfrate(vf,0);
1050 int ov_halfrate_p(OggVorbis_File *vf){
1051 if(vf->vi==NULL)return OV_EINVAL;
1052 return vorbis_synthesis_halfrate_p(vf->vi);
1055 /* Only partially open the vorbis file; test for Vorbisness, and load
1056 the headers for the first chain. Do not seek (although test for
1057 seekability). Use ov_test_open to finish opening the file, else
1058 ov_clear to close/free it. Same return codes as open.
1060 Note that vorbisfile does _not_ take ownership of the file if the
1061 call fails; the calling applicaiton is responsible for closing the file
1062 if this call returns an error. */
1064 int ov_test_callbacks(void *f,OggVorbis_File *vf,
1065 const char *initial,long ibytes,ov_callbacks callbacks)
1067 return _ov_open1(f,vf,initial,ibytes,callbacks);
1070 int ov_test(FILE *f,OggVorbis_File *vf,const char *initial,long ibytes){
1071 ov_callbacks callbacks = {
1072 (size_t (*)(void *, size_t, size_t, void *)) fread,
1073 (int (*)(void *, ogg_int64_t, int)) _fseek64_wrap,
1074 (int (*)(void *)) fclose,
1075 (long (*)(void *)) ftell
1078 return ov_test_callbacks((void *)f, vf, initial, ibytes, callbacks);
1081 int ov_test_open(OggVorbis_File *vf){
1082 if(vf->ready_state!=PARTOPEN)return(OV_EINVAL);
1083 return _ov_open2(vf);
1086 /* How many logical bitstreams in this physical bitstream? */
1087 long ov_streams(OggVorbis_File *vf){
1091 /* Is the FILE * associated with vf seekable? */
1092 long ov_seekable(OggVorbis_File *vf){
1093 return vf->seekable;
1096 /* returns the bitrate for a given logical bitstream or the entire
1097 physical bitstream. If the file is open for random access, it will
1098 find the *actual* average bitrate. If the file is streaming, it
1099 returns the nominal bitrate (if set) else the average of the
1100 upper/lower bounds (if set) else -1 (unset).
1102 If you want the actual bitrate field settings, get them from the
1103 vorbis_info structs */
1105 long ov_bitrate(OggVorbis_File *vf,int i){
1106 if(vf->ready_state<OPENED)return(OV_EINVAL);
1107 if(i>=vf->links)return(OV_EINVAL);
1108 if(!vf->seekable && i!=0)return(ov_bitrate(vf,0));
1113 for(i=0;i<vf->links;i++)
1114 bits+=(vf->offsets[i+1]-vf->dataoffsets[i])*8;
1115 /* This once read: return(rint(bits/ov_time_total(vf,-1)));
1116 * gcc 3.x on x86 miscompiled this at optimisation level 2 and above,
1117 * so this is slightly transformed to make it work.
1119 br = bits/ov_time_total(vf,-1);
1123 /* return the actual bitrate */
1124 return(rint((vf->offsets[i+1]-vf->dataoffsets[i])*8/ov_time_total(vf,i)));
1126 /* return nominal if set */
1127 if(vf->vi[i].bitrate_nominal>0){
1128 return vf->vi[i].bitrate_nominal;
1130 if(vf->vi[i].bitrate_upper>0){
1131 if(vf->vi[i].bitrate_lower>0){
1132 return (vf->vi[i].bitrate_upper+vf->vi[i].bitrate_lower)/2;
1134 return vf->vi[i].bitrate_upper;
1143 /* returns the actual bitrate since last call. returns -1 if no
1144 additional data to offer since last call (or at beginning of stream),
1145 EINVAL if stream is only partially open
1147 long ov_bitrate_instant(OggVorbis_File *vf){
1148 int link=(vf->seekable?vf->current_link:0);
1150 if(vf->ready_state<OPENED)return(OV_EINVAL);
1151 if(vf->samptrack==0)return(OV_FALSE);
1152 ret=vf->bittrack/vf->samptrack*vf->vi[link].rate+.5;
1159 long ov_serialnumber(OggVorbis_File *vf,int i){
1160 if(i>=vf->links)return(ov_serialnumber(vf,vf->links-1));
1161 if(!vf->seekable && i>=0)return(ov_serialnumber(vf,-1));
1163 return(vf->current_serialno);
1165 return(vf->serialnos[i]);
1169 /* returns: total raw (compressed) length of content if i==-1
1170 raw (compressed) length of that logical bitstream for i==0 to n
1171 OV_EINVAL if the stream is not seekable (we can't know the length)
1172 or if stream is only partially open
1174 ogg_int64_t ov_raw_total(OggVorbis_File *vf,int i){
1175 if(vf->ready_state<OPENED)return(OV_EINVAL);
1176 if(!vf->seekable || i>=vf->links)return(OV_EINVAL);
1180 for(i=0;i<vf->links;i++)
1181 acc+=ov_raw_total(vf,i);
1184 return(vf->offsets[i+1]-vf->offsets[i]);
1188 /* returns: total PCM length (samples) of content if i==-1 PCM length
1189 (samples) of that logical bitstream for i==0 to n
1190 OV_EINVAL if the stream is not seekable (we can't know the
1191 length) or only partially open
1193 ogg_int64_t ov_pcm_total(OggVorbis_File *vf,int i){
1194 if(vf->ready_state<OPENED)return(OV_EINVAL);
1195 if(!vf->seekable || i>=vf->links)return(OV_EINVAL);
1199 for(i=0;i<vf->links;i++)
1200 acc+=ov_pcm_total(vf,i);
1203 return(vf->pcmlengths[i*2+1]);
1207 /* returns: total seconds of content if i==-1
1208 seconds in that logical bitstream for i==0 to n
1209 OV_EINVAL if the stream is not seekable (we can't know the
1210 length) or only partially open
1212 double ov_time_total(OggVorbis_File *vf,int i){
1213 if(vf->ready_state<OPENED)return(OV_EINVAL);
1214 if(!vf->seekable || i>=vf->links)return(OV_EINVAL);
1218 for(i=0;i<vf->links;i++)
1219 acc+=ov_time_total(vf,i);
1222 return((double)(vf->pcmlengths[i*2+1])/vf->vi[i].rate);
1226 /* seek to an offset relative to the *compressed* data. This also
1227 scans packets to update the PCM cursor. It will cross a logical
1228 bitstream boundary, but only if it can't get any packets out of the
1229 tail of the bitstream we seek to (so no surprises).
1231 returns zero on success, nonzero on failure */
1233 int ov_raw_seek(OggVorbis_File *vf,ogg_int64_t pos){
1234 ogg_stream_state work_os;
1237 if(vf->ready_state<OPENED)return(OV_EINVAL);
1239 return(OV_ENOSEEK); /* don't dump machine if we can't seek */
1241 if(pos<0 || pos>vf->end)return(OV_EINVAL);
1243 /* is the seek position outside our current link [if any]? */
1244 if(vf->ready_state>=STREAMSET){
1245 if(pos<vf->offsets[vf->current_link] || pos>=vf->offsets[vf->current_link+1])
1246 _decode_clear(vf); /* clear out stream state */
1249 /* don't yet clear out decoding machine (if it's initialized), in
1250 the case we're in the same link. Restart the decode lapping, and
1251 let _fetch_and_process_packet deal with a potential bitstream
1254 ogg_stream_reset_serialno(&vf->os,
1255 vf->current_serialno); /* must set serialno */
1256 vorbis_synthesis_restart(&vf->vd);
1258 ret=_seek_helper(vf,pos);
1259 if(ret)goto seek_error;
1261 /* we need to make sure the pcm_offset is set, but we don't want to
1262 advance the raw cursor past good packets just to get to the first
1263 with a granulepos. That's not equivalent behavior to beginning
1264 decoding as immediately after the seek position as possible.
1266 So, a hack. We use two stream states; a local scratch state and
1267 the shared vf->os stream state. We use the local state to
1268 scan, and the shared state as a buffer for later decode.
1270 Unfortuantely, on the last page we still advance to last packet
1271 because the granulepos on the last page is not necessarily on a
1272 packet boundary, and we need to make sure the granpos is
1284 ogg_int64_t pagepos=-1;
1286 ogg_stream_init(&work_os,vf->current_serialno); /* get the memory ready */
1287 ogg_stream_reset(&work_os); /* eliminate the spurious OV_HOLE
1288 return from not necessarily
1289 starting from the beginning */
1292 if(vf->ready_state>=STREAMSET){
1293 /* snarf/scan a packet if we can */
1294 int result=ogg_stream_packetout(&work_os,&op);
1298 if(vf->vi[vf->current_link].codec_setup){
1299 thisblock=vorbis_packet_blocksize(vf->vi+vf->current_link,&op);
1301 ogg_stream_packetout(&vf->os,NULL);
1305 /* We can't get a guaranteed correct pcm position out of the
1306 last page in a stream because it might have a 'short'
1307 granpos, which can only be detected in the presence of a
1308 preceding page. However, if the last page is also the first
1309 page, the granpos rules of a first page take precedence. Not
1310 only that, but for first==last, the EOS page must be treated
1311 as if its a normal first page for the stream to open/play. */
1312 if(lastflag && !firstflag)
1313 ogg_stream_packetout(&vf->os,NULL);
1315 if(lastblock)accblock+=(lastblock+thisblock)>>2;
1318 if(op.granulepos!=-1){
1319 int i,link=vf->current_link;
1320 ogg_int64_t granulepos=op.granulepos-vf->pcmlengths[link*2];
1321 if(granulepos<0)granulepos=0;
1324 granulepos+=vf->pcmlengths[i*2+1];
1325 vf->pcm_offset=granulepos-accblock;
1326 if(vf->pcm_offset<0)vf->pcm_offset=0;
1329 lastblock=thisblock;
1332 ogg_stream_packetout(&vf->os,NULL);
1337 pagepos=_get_next_page(vf,&og,-1);
1339 vf->pcm_offset=ov_pcm_total(vf,-1);
1343 /* huh? Bogus stream with packets but no granulepos */
1348 /* has our decoding just traversed a bitstream boundary? */
1349 if(vf->ready_state>=STREAMSET){
1350 if(vf->current_serialno!=ogg_page_serialno(&og)){
1352 /* two possibilities:
1353 1) our decoding just traversed a bitstream boundary
1354 2) another stream is multiplexed into this logical section? */
1356 if(ogg_page_bos(&og)){
1358 _decode_clear(vf); /* clear out stream state */
1359 ogg_stream_clear(&work_os);
1360 } /* else, do nothing; next loop will scoop another page */
1364 if(vf->ready_state<STREAMSET){
1366 long serialno = ogg_page_serialno(&og);
1368 for(link=0;link<vf->links;link++)
1369 if(vf->serialnos[link]==serialno)break;
1371 if(link==vf->links) continue; /* not the desired Vorbis
1372 bitstream section; keep
1374 vf->current_link=link;
1375 vf->current_serialno=serialno;
1376 ogg_stream_reset_serialno(&vf->os,serialno);
1377 ogg_stream_reset_serialno(&work_os,serialno);
1378 vf->ready_state=STREAMSET;
1379 firstflag=(pagepos<=vf->dataoffsets[link]);
1382 ogg_stream_pagein(&vf->os,&og);
1383 ogg_stream_pagein(&work_os,&og);
1384 lastflag=ogg_page_eos(&og);
1389 ogg_stream_clear(&work_os);
1395 /* dump the machine so we're in a known state */
1397 ogg_stream_clear(&work_os);
1402 /* Page granularity seek (faster than sample granularity because we
1403 don't do the last bit of decode to find a specific sample).
1405 Seek to the last [granule marked] page preceding the specified pos
1406 location, such that decoding past the returned point will quickly
1407 arrive at the requested position. */
1408 int ov_pcm_seek_page(OggVorbis_File *vf,ogg_int64_t pos){
1410 ogg_int64_t result=0;
1411 ogg_int64_t total=ov_pcm_total(vf,-1);
1413 if(vf->ready_state<OPENED)return(OV_EINVAL);
1414 if(!vf->seekable)return(OV_ENOSEEK);
1416 if(pos<0 || pos>total)return(OV_EINVAL);
1418 /* which bitstream section does this pcm offset occur in? */
1419 for(link=vf->links-1;link>=0;link--){
1420 total-=vf->pcmlengths[link*2+1];
1421 if(pos>=total)break;
1424 /* search within the logical bitstream for the page with the highest
1425 pcm_pos preceding (or equal to) pos. There is a danger here;
1426 missing pages or incorrect frame number information in the
1427 bitstream could make our task impossible. Account for that (it
1428 would be an error condition) */
1430 /* new search algorithm by HB (Nicholas Vinen) */
1432 ogg_int64_t end=vf->offsets[link+1];
1433 ogg_int64_t begin=vf->offsets[link];
1434 ogg_int64_t begintime = vf->pcmlengths[link*2];
1435 ogg_int64_t endtime = vf->pcmlengths[link*2+1]+begintime;
1436 ogg_int64_t target=pos-total+begintime;
1437 ogg_int64_t best=begin;
1443 if(end-begin<CHUNKSIZE){
1446 /* take a (pretty decent) guess. */
1448 (ogg_int64_t)((double)(target-begintime)*(end-begin)/(endtime-begintime))
1450 if(bisect<begin+CHUNKSIZE)
1454 if(bisect!=vf->offset){
1455 result=_seek_helper(vf,bisect);
1456 if(result) goto seek_error;
1460 result=_get_next_page(vf,&og,end-vf->offset);
1461 if(result==OV_EREAD) goto seek_error;
1464 end=begin; /* found it */
1466 if(bisect==0) goto seek_error;
1468 if(bisect<=begin)bisect=begin+1;
1469 result=_seek_helper(vf,bisect);
1470 if(result) goto seek_error;
1473 ogg_int64_t granulepos;
1475 if(ogg_page_serialno(&og)!=vf->serialnos[link])
1478 granulepos=ogg_page_granulepos(&og);
1479 if(granulepos==-1)continue;
1481 if(granulepos<target){
1482 best=result; /* raw offset of packet with granulepos */
1483 begin=vf->offset; /* raw offset of next page */
1484 begintime=granulepos;
1486 if(target-begintime>44100)break;
1487 bisect=begin; /* *not* begin + 1 */
1490 end=begin; /* found it */
1492 if(end==vf->offset){ /* we're pretty close - we'd be stuck in */
1494 bisect-=CHUNKSIZE; /* an endless loop otherwise. */
1495 if(bisect<=begin)bisect=begin+1;
1496 result=_seek_helper(vf,bisect);
1497 if(result) goto seek_error;
1509 /* found our page. seek to it, update pcm offset. Easier case than
1510 raw_seek, don't keep packets preceding granulepos. */
1516 result=_seek_helper(vf,best);
1518 if(result) goto seek_error;
1519 result=_get_next_page(vf,&og,-1);
1520 if(result<0) goto seek_error;
1522 if(link!=vf->current_link){
1523 /* Different link; dump entire decode machine */
1526 vf->current_link=link;
1527 vf->current_serialno=vf->serialnos[link];
1528 vf->ready_state=STREAMSET;
1531 vorbis_synthesis_restart(&vf->vd);
1534 ogg_stream_reset_serialno(&vf->os,vf->current_serialno);
1535 ogg_stream_pagein(&vf->os,&og);
1537 /* pull out all but last packet; the one with granulepos */
1539 result=ogg_stream_packetpeek(&vf->os,&op);
1541 /* !!! the packet finishing this page originated on a
1542 preceding page. Keep fetching previous pages until we
1543 get one with a granulepos or without the 'continued' flag
1544 set. Then just use raw_seek for simplicity. */
1546 result=_seek_helper(vf,best);
1547 if(result<0) goto seek_error;
1550 result=_get_prev_page(vf,&og);
1551 if(result<0) goto seek_error;
1552 if(ogg_page_serialno(&og)==vf->current_serialno &&
1553 (ogg_page_granulepos(&og)>-1 ||
1554 !ogg_page_continued(&og))){
1555 return ov_raw_seek(vf,result);
1561 result = OV_EBADPACKET;
1564 if(op.granulepos!=-1){
1565 vf->pcm_offset=op.granulepos-vf->pcmlengths[vf->current_link*2];
1566 if(vf->pcm_offset<0)vf->pcm_offset=0;
1567 vf->pcm_offset+=total;
1570 result=ogg_stream_packetout(&vf->os,NULL);
1576 if(vf->pcm_offset>pos || pos>ov_pcm_total(vf,-1)){
1585 /* dump machine so we're in a known state */
1591 /* seek to a sample offset relative to the decompressed pcm stream
1592 returns zero on success, nonzero on failure */
1594 int ov_pcm_seek(OggVorbis_File *vf,ogg_int64_t pos){
1595 int thisblock,lastblock=0;
1596 int ret=ov_pcm_seek_page(vf,pos);
1597 if(ret<0)return(ret);
1598 if((ret=_make_decode_ready(vf)))return ret;
1600 /* discard leading packets we don't need for the lapping of the
1601 position we want; don't decode them */
1607 int ret=ogg_stream_packetpeek(&vf->os,&op);
1609 thisblock=vorbis_packet_blocksize(vf->vi+vf->current_link,&op);
1611 ogg_stream_packetout(&vf->os,NULL);
1612 continue; /* non audio packet */
1614 if(lastblock)vf->pcm_offset+=(lastblock+thisblock)>>2;
1616 if(vf->pcm_offset+((thisblock+
1617 vorbis_info_blocksize(vf->vi,1))>>2)>=pos)break;
1619 /* remove the packet from packet queue and track its granulepos */
1620 ogg_stream_packetout(&vf->os,NULL);
1621 vorbis_synthesis_trackonly(&vf->vb,&op); /* set up a vb with
1624 vorbis_synthesis_blockin(&vf->vd,&vf->vb);
1626 /* end of logical stream case is hard, especially with exact
1627 length positioning. */
1629 if(op.granulepos>-1){
1631 /* always believe the stream markers */
1632 vf->pcm_offset=op.granulepos-vf->pcmlengths[vf->current_link*2];
1633 if(vf->pcm_offset<0)vf->pcm_offset=0;
1634 for(i=0;i<vf->current_link;i++)
1635 vf->pcm_offset+=vf->pcmlengths[i*2+1];
1638 lastblock=thisblock;
1641 if(ret<0 && ret!=OV_HOLE)break;
1643 /* suck in a new page */
1644 if(_get_next_page(vf,&og,-1)<0)break;
1645 if(ogg_page_bos(&og))_decode_clear(vf);
1647 if(vf->ready_state<STREAMSET){
1648 long serialno=ogg_page_serialno(&og);
1651 for(link=0;link<vf->links;link++)
1652 if(vf->serialnos[link]==serialno)break;
1653 if(link==vf->links) continue;
1654 vf->current_link=link;
1656 vf->ready_state=STREAMSET;
1657 vf->current_serialno=ogg_page_serialno(&og);
1658 ogg_stream_reset_serialno(&vf->os,serialno);
1659 ret=_make_decode_ready(vf);
1664 ogg_stream_pagein(&vf->os,&og);
1670 /* discard samples until we reach the desired position. Crossing a
1671 logical bitstream boundary with abandon is OK. */
1673 /* note that halfrate could be set differently in each link, but
1674 vorbisfile encoforces all links are set or unset */
1675 int hs=vorbis_synthesis_halfrate_p(vf->vi);
1676 while(vf->pcm_offset<((pos>>hs)<<hs)){
1677 ogg_int64_t target=(pos-vf->pcm_offset)>>hs;
1678 long samples=vorbis_synthesis_pcmout(&vf->vd,NULL);
1680 if(samples>target)samples=target;
1681 vorbis_synthesis_read(&vf->vd,samples);
1682 vf->pcm_offset+=samples<<hs;
1685 if(_fetch_and_process_packet(vf,NULL,1,1)<=0)
1686 vf->pcm_offset=ov_pcm_total(vf,-1); /* eof */
1692 /* seek to a playback time relative to the decompressed pcm stream
1693 returns zero on success, nonzero on failure */
1694 int ov_time_seek(OggVorbis_File *vf,double seconds){
1695 /* translate time to PCM position and call ov_pcm_seek */
1698 ogg_int64_t pcm_total=0;
1699 double time_total=0.;
1701 if(vf->ready_state<OPENED)return(OV_EINVAL);
1702 if(!vf->seekable)return(OV_ENOSEEK);
1703 if(seconds<0)return(OV_EINVAL);
1705 /* which bitstream section does this time offset occur in? */
1706 for(link=0;link<vf->links;link++){
1707 double addsec = ov_time_total(vf,link);
1708 if(seconds<time_total+addsec)break;
1710 pcm_total+=vf->pcmlengths[link*2+1];
1713 if(link==vf->links)return(OV_EINVAL);
1715 /* enough information to convert time offset to pcm offset */
1717 ogg_int64_t target=pcm_total+(seconds-time_total)*vf->vi[link].rate;
1718 return(ov_pcm_seek(vf,target));
1722 /* page-granularity version of ov_time_seek
1723 returns zero on success, nonzero on failure */
1724 int ov_time_seek_page(OggVorbis_File *vf,double seconds){
1725 /* translate time to PCM position and call ov_pcm_seek */
1728 ogg_int64_t pcm_total=0;
1729 double time_total=0.;
1731 if(vf->ready_state<OPENED)return(OV_EINVAL);
1732 if(!vf->seekable)return(OV_ENOSEEK);
1733 if(seconds<0)return(OV_EINVAL);
1735 /* which bitstream section does this time offset occur in? */
1736 for(link=0;link<vf->links;link++){
1737 double addsec = ov_time_total(vf,link);
1738 if(seconds<time_total+addsec)break;
1740 pcm_total+=vf->pcmlengths[link*2+1];
1743 if(link==vf->links)return(OV_EINVAL);
1745 /* enough information to convert time offset to pcm offset */
1747 ogg_int64_t target=pcm_total+(seconds-time_total)*vf->vi[link].rate;
1748 return(ov_pcm_seek_page(vf,target));
1752 /* tell the current stream offset cursor. Note that seek followed by
1753 tell will likely not give the set offset due to caching */
1754 ogg_int64_t ov_raw_tell(OggVorbis_File *vf){
1755 if(vf->ready_state<OPENED)return(OV_EINVAL);
1759 /* return PCM offset (sample) of next PCM sample to be read */
1760 ogg_int64_t ov_pcm_tell(OggVorbis_File *vf){
1761 if(vf->ready_state<OPENED)return(OV_EINVAL);
1762 return(vf->pcm_offset);
1765 /* return time offset (seconds) of next PCM sample to be read */
1766 double ov_time_tell(OggVorbis_File *vf){
1768 ogg_int64_t pcm_total=0;
1769 double time_total=0.f;
1771 if(vf->ready_state<OPENED)return(OV_EINVAL);
1773 pcm_total=ov_pcm_total(vf,-1);
1774 time_total=ov_time_total(vf,-1);
1776 /* which bitstream section does this time offset occur in? */
1777 for(link=vf->links-1;link>=0;link--){
1778 pcm_total-=vf->pcmlengths[link*2+1];
1779 time_total-=ov_time_total(vf,link);
1780 if(vf->pcm_offset>=pcm_total)break;
1784 return((double)time_total+(double)(vf->pcm_offset-pcm_total)/vf->vi[link].rate);
1787 /* link: -1) return the vorbis_info struct for the bitstream section
1788 currently being decoded
1789 0-n) to request information for a specific bitstream section
1791 In the case of a non-seekable bitstream, any call returns the
1792 current bitstream. NULL in the case that the machine is not
1795 vorbis_info *ov_info(OggVorbis_File *vf,int link){
1798 if(vf->ready_state>=STREAMSET)
1799 return vf->vi+vf->current_link;
1812 /* grr, strong typing, grr, no templates/inheritence, grr */
1813 vorbis_comment *ov_comment(OggVorbis_File *vf,int link){
1816 if(vf->ready_state>=STREAMSET)
1817 return vf->vc+vf->current_link;
1830 static int host_is_big_endian() {
1831 ogg_int32_t pattern = 0xfeedface; /* deadbeef */
1832 unsigned char *bytewise = (unsigned char *)&pattern;
1833 if (bytewise[0] == 0xfe) return 1;
1837 /* up to this point, everything could more or less hide the multiple
1838 logical bitstream nature of chaining from the toplevel application
1839 if the toplevel application didn't particularly care. However, at
1840 the point that we actually read audio back, the multiple-section
1841 nature must surface: Multiple bitstream sections do not necessarily
1842 have to have the same number of channels or sampling rate.
1844 ov_read returns the sequential logical bitstream number currently
1845 being decoded along with the PCM data in order that the toplevel
1846 application can take action on channel/sample rate changes. This
1847 number will be incremented even for streamed (non-seekable) streams
1848 (for seekable streams, it represents the actual logical bitstream
1849 index within the physical bitstream. Note that the accessor
1850 functions above are aware of this dichotomy).
1852 ov_read_filter is exactly the same as ov_read except that it processes
1853 the decoded audio data through a filter before packing it into the
1854 requested format. This gives greater accuracy than applying a filter
1855 after the audio has been converted into integral PCM.
1857 input values: buffer) a buffer to hold packed PCM data for return
1858 length) the byte length requested to be placed into buffer
1859 bigendianp) should the data be packed LSB first (0) or
1861 word) word size for output. currently 1 (byte) or
1864 return values: <0) error/hole in data (OV_HOLE), partial open (OV_EINVAL)
1866 n) number of bytes of PCM actually returned. The
1867 below works on a packet-by-packet basis, so the
1868 return length is not related to the 'length' passed
1869 in, just guaranteed to fit.
1871 *section) set to the logical bitstream number */
1873 long ov_read_filter(OggVorbis_File *vf,char *buffer,int length,
1874 int bigendianp,int word,int sgned,int *bitstream,
1875 void (*filter)(float **pcm,long channels,long samples,void *filter_param),void *filter_param){
1877 int host_endian = host_is_big_endian();
1883 if(vf->ready_state<OPENED)return(OV_EINVAL);
1886 if(vf->ready_state==INITSET){
1887 samples=vorbis_synthesis_pcmout(&vf->vd,&pcm);
1891 /* suck in another packet */
1893 int ret=_fetch_and_process_packet(vf,NULL,1,1);
1904 /* yay! proceed to pack data into the byte buffer */
1906 long channels=ov_info(vf,-1)->channels;
1907 long bytespersample=word * channels;
1908 vorbis_fpu_control fpu;
1909 if(samples>length/bytespersample)samples=length/bytespersample;
1916 filter(pcm,channels,samples,filter_param);
1918 /* a tight loop to pack each size */
1922 int off=(sgned?0:128);
1923 vorbis_fpu_setround(&fpu);
1924 for(j=0;j<samples;j++)
1925 for(i=0;i<channels;i++){
1926 val=vorbis_ftoi(pcm[i][j]*128.f);
1928 else if(val<-128)val=-128;
1931 vorbis_fpu_restore(fpu);
1933 int off=(sgned?0:32768);
1935 if(host_endian==bigendianp){
1938 vorbis_fpu_setround(&fpu);
1939 for(i=0;i<channels;i++) { /* It's faster in this order */
1941 short *dest=((short *)buffer)+i;
1942 for(j=0;j<samples;j++) {
1943 val=vorbis_ftoi(src[j]*32768.f);
1944 if(val>32767)val=32767;
1945 else if(val<-32768)val=-32768;
1950 vorbis_fpu_restore(fpu);
1954 vorbis_fpu_setround(&fpu);
1955 for(i=0;i<channels;i++) {
1957 short *dest=((short *)buffer)+i;
1958 for(j=0;j<samples;j++) {
1959 val=vorbis_ftoi(src[j]*32768.f);
1960 if(val>32767)val=32767;
1961 else if(val<-32768)val=-32768;
1966 vorbis_fpu_restore(fpu);
1969 }else if(bigendianp){
1971 vorbis_fpu_setround(&fpu);
1972 for(j=0;j<samples;j++)
1973 for(i=0;i<channels;i++){
1974 val=vorbis_ftoi(pcm[i][j]*32768.f);
1975 if(val>32767)val=32767;
1976 else if(val<-32768)val=-32768;
1979 *buffer++=(val&0xff);
1981 vorbis_fpu_restore(fpu);
1985 vorbis_fpu_setround(&fpu);
1986 for(j=0;j<samples;j++)
1987 for(i=0;i<channels;i++){
1988 val=vorbis_ftoi(pcm[i][j]*32768.f);
1989 if(val>32767)val=32767;
1990 else if(val<-32768)val=-32768;
1992 *buffer++=(val&0xff);
1995 vorbis_fpu_restore(fpu);
2001 vorbis_synthesis_read(&vf->vd,samples);
2002 hs=vorbis_synthesis_halfrate_p(vf->vi);
2003 vf->pcm_offset+=(samples<<hs);
2004 if(bitstream)*bitstream=vf->current_link;
2005 return(samples*bytespersample);
2011 long ov_read(OggVorbis_File *vf,char *buffer,int length,
2012 int bigendianp,int word,int sgned,int *bitstream){
2013 return ov_read_filter(vf, buffer, length, bigendianp, word, sgned, bitstream, NULL, NULL);
2016 /* input values: pcm_channels) a float vector per channel of output
2017 length) the sample length being read by the app
2019 return values: <0) error/hole in data (OV_HOLE), partial open (OV_EINVAL)
2021 n) number of samples of PCM actually returned. The
2022 below works on a packet-by-packet basis, so the
2023 return length is not related to the 'length' passed
2024 in, just guaranteed to fit.
2026 *section) set to the logical bitstream number */
2030 long ov_read_float(OggVorbis_File *vf,float ***pcm_channels,int length,
2033 if(vf->ready_state<OPENED)return(OV_EINVAL);
2036 if(vf->ready_state==INITSET){
2038 long samples=vorbis_synthesis_pcmout(&vf->vd,&pcm);
2040 int hs=vorbis_synthesis_halfrate_p(vf->vi);
2041 if(pcm_channels)*pcm_channels=pcm;
2042 if(samples>length)samples=length;
2043 vorbis_synthesis_read(&vf->vd,samples);
2044 vf->pcm_offset+=samples<<hs;
2045 if(bitstream)*bitstream=vf->current_link;
2051 /* suck in another packet */
2053 int ret=_fetch_and_process_packet(vf,NULL,1,1);
2054 if(ret==OV_EOF)return(0);
2055 if(ret<=0)return(ret);
2061 extern float *vorbis_window(vorbis_dsp_state *v,int W);
2063 static void _ov_splice(float **pcm,float **lappcm,
2066 float *w1, float *w2){
2077 for(j=0;j<ch1 && j<ch2;j++){
2084 d[i]=d[i]*wd + s[i]*ws;
2087 /* window from zero */
2098 /* make sure vf is INITSET */
2099 static int _ov_initset(OggVorbis_File *vf){
2101 if(vf->ready_state==INITSET)break;
2102 /* suck in another packet */
2104 int ret=_fetch_and_process_packet(vf,NULL,1,0);
2105 if(ret<0 && ret!=OV_HOLE)return(ret);
2111 /* make sure vf is INITSET and that we have a primed buffer; if
2112 we're crosslapping at a stream section boundary, this also makes
2113 sure we're sanity checking against the right stream information */
2114 static int _ov_initprime(OggVorbis_File *vf){
2115 vorbis_dsp_state *vd=&vf->vd;
2117 if(vf->ready_state==INITSET)
2118 if(vorbis_synthesis_pcmout(vd,NULL))break;
2120 /* suck in another packet */
2122 int ret=_fetch_and_process_packet(vf,NULL,1,0);
2123 if(ret<0 && ret!=OV_HOLE)return(ret);
2129 /* grab enough data for lapping from vf; this may be in the form of
2130 unreturned, already-decoded pcm, remaining PCM we will need to
2131 decode, or synthetic postextrapolation from last packets. */
2132 static void _ov_getlap(OggVorbis_File *vf,vorbis_info *vi,vorbis_dsp_state *vd,
2133 float **lappcm,int lapsize){
2137 /* try first to decode the lapping data */
2138 while(lapcount<lapsize){
2139 int samples=vorbis_synthesis_pcmout(vd,&pcm);
2141 if(samples>lapsize-lapcount)samples=lapsize-lapcount;
2142 for(i=0;i<vi->channels;i++)
2143 memcpy(lappcm[i]+lapcount,pcm[i],sizeof(**pcm)*samples);
2145 vorbis_synthesis_read(vd,samples);
2147 /* suck in another packet */
2148 int ret=_fetch_and_process_packet(vf,NULL,1,0); /* do *not* span */
2149 if(ret==OV_EOF)break;
2152 if(lapcount<lapsize){
2153 /* failed to get lapping data from normal decode; pry it from the
2154 postextrapolation buffering, or the second half of the MDCT
2155 from the last packet */
2156 int samples=vorbis_synthesis_lapout(&vf->vd,&pcm);
2158 for(i=0;i<vi->channels;i++)
2159 memset(lappcm[i]+lapcount,0,sizeof(**pcm)*lapsize-lapcount);
2162 if(samples>lapsize-lapcount)samples=lapsize-lapcount;
2163 for(i=0;i<vi->channels;i++)
2164 memcpy(lappcm[i]+lapcount,pcm[i],sizeof(**pcm)*samples);
2170 /* this sets up crosslapping of a sample by using trailing data from
2171 sample 1 and lapping it into the windowing buffer of sample 2 */
2172 int ov_crosslap(OggVorbis_File *vf1, OggVorbis_File *vf2){
2173 vorbis_info *vi1,*vi2;
2177 int n1,n2,i,ret,hs1,hs2;
2179 if(vf1==vf2)return(0); /* degenerate case */
2180 if(vf1->ready_state<OPENED)return(OV_EINVAL);
2181 if(vf2->ready_state<OPENED)return(OV_EINVAL);
2183 /* the relevant overlap buffers must be pre-checked and pre-primed
2184 before looking at settings in the event that priming would cross
2185 a bitstream boundary. So, do it now */
2187 ret=_ov_initset(vf1);
2189 ret=_ov_initprime(vf2);
2192 vi1=ov_info(vf1,-1);
2193 vi2=ov_info(vf2,-1);
2194 hs1=ov_halfrate_p(vf1);
2195 hs2=ov_halfrate_p(vf2);
2197 lappcm=alloca(sizeof(*lappcm)*vi1->channels);
2198 n1=vorbis_info_blocksize(vi1,0)>>(1+hs1);
2199 n2=vorbis_info_blocksize(vi2,0)>>(1+hs2);
2200 w1=vorbis_window(&vf1->vd,0);
2201 w2=vorbis_window(&vf2->vd,0);
2203 for(i=0;i<vi1->channels;i++)
2204 lappcm[i]=alloca(sizeof(**lappcm)*n1);
2206 _ov_getlap(vf1,vi1,&vf1->vd,lappcm,n1);
2208 /* have a lapping buffer from vf1; now to splice it into the lapping
2210 /* consolidate and expose the buffer. */
2211 vorbis_synthesis_lapout(&vf2->vd,&pcm);
2214 _analysis_output_always("pcmL",0,pcm[0],n1*2,0,0,0);
2215 _analysis_output_always("pcmR",0,pcm[1],n1*2,0,0,0);
2219 _ov_splice(pcm,lappcm,n1,n2,vi1->channels,vi2->channels,w1,w2);
2225 static int _ov_64_seek_lap(OggVorbis_File *vf,ogg_int64_t pos,
2226 int (*localseek)(OggVorbis_File *,ogg_int64_t)){
2231 int n1,n2,ch1,ch2,hs;
2234 if(vf->ready_state<OPENED)return(OV_EINVAL);
2235 ret=_ov_initset(vf);
2238 hs=ov_halfrate_p(vf);
2241 n1=vorbis_info_blocksize(vi,0)>>(1+hs);
2242 w1=vorbis_window(&vf->vd,0); /* window arrays from libvorbis are
2243 persistent; even if the decode state
2244 from this link gets dumped, this
2245 window array continues to exist */
2247 lappcm=alloca(sizeof(*lappcm)*ch1);
2249 lappcm[i]=alloca(sizeof(**lappcm)*n1);
2250 _ov_getlap(vf,vi,&vf->vd,lappcm,n1);
2252 /* have lapping data; seek and prime the buffer */
2253 ret=localseek(vf,pos);
2255 ret=_ov_initprime(vf);
2258 /* Guard against cross-link changes; they're perfectly legal */
2261 n2=vorbis_info_blocksize(vi,0)>>(1+hs);
2262 w2=vorbis_window(&vf->vd,0);
2264 /* consolidate and expose the buffer. */
2265 vorbis_synthesis_lapout(&vf->vd,&pcm);
2268 _ov_splice(pcm,lappcm,n1,n2,ch1,ch2,w1,w2);
2274 int ov_raw_seek_lap(OggVorbis_File *vf,ogg_int64_t pos){
2275 return _ov_64_seek_lap(vf,pos,ov_raw_seek);
2278 int ov_pcm_seek_lap(OggVorbis_File *vf,ogg_int64_t pos){
2279 return _ov_64_seek_lap(vf,pos,ov_pcm_seek);
2282 int ov_pcm_seek_page_lap(OggVorbis_File *vf,ogg_int64_t pos){
2283 return _ov_64_seek_lap(vf,pos,ov_pcm_seek_page);
2286 static int _ov_d_seek_lap(OggVorbis_File *vf,double pos,
2287 int (*localseek)(OggVorbis_File *,double)){
2292 int n1,n2,ch1,ch2,hs;
2295 if(vf->ready_state<OPENED)return(OV_EINVAL);
2296 ret=_ov_initset(vf);
2299 hs=ov_halfrate_p(vf);
2302 n1=vorbis_info_blocksize(vi,0)>>(1+hs);
2303 w1=vorbis_window(&vf->vd,0); /* window arrays from libvorbis are
2304 persistent; even if the decode state
2305 from this link gets dumped, this
2306 window array continues to exist */
2308 lappcm=alloca(sizeof(*lappcm)*ch1);
2310 lappcm[i]=alloca(sizeof(**lappcm)*n1);
2311 _ov_getlap(vf,vi,&vf->vd,lappcm,n1);
2313 /* have lapping data; seek and prime the buffer */
2314 ret=localseek(vf,pos);
2316 ret=_ov_initprime(vf);
2319 /* Guard against cross-link changes; they're perfectly legal */
2322 n2=vorbis_info_blocksize(vi,0)>>(1+hs);
2323 w2=vorbis_window(&vf->vd,0);
2325 /* consolidate and expose the buffer. */
2326 vorbis_synthesis_lapout(&vf->vd,&pcm);
2329 _ov_splice(pcm,lappcm,n1,n2,ch1,ch2,w1,w2);
2335 int ov_time_seek_lap(OggVorbis_File *vf,double pos){
2336 return _ov_d_seek_lap(vf,pos,ov_time_seek);
2339 int ov_time_seek_page_lap(OggVorbis_File *vf,double pos){
2340 return _ov_d_seek_lap(vf,pos,ov_time_seek_page);