diff options
Diffstat (limited to 'Tremolo/vorbisfile.c')
| -rw-r--r-- | Tremolo/vorbisfile.c | 1592 |
1 files changed, 0 insertions, 1592 deletions
diff --git a/Tremolo/vorbisfile.c b/Tremolo/vorbisfile.c deleted file mode 100644 index 7b6ce47..0000000 --- a/Tremolo/vorbisfile.c +++ /dev/null @@ -1,1592 +0,0 @@ -/******************************************************************** - * * - * THIS FILE IS PART OF THE OggVorbis 'TREMOR' CODEC SOURCE CODE. * - * * - * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS * - * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE * - * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING. * - * * - * THE OggVorbis 'TREMOR' SOURCE CODE IS (C) COPYRIGHT 1994-2003 * - * BY THE Xiph.Org FOUNDATION http://www.xiph.org/ * - * * - ******************************************************************** - - function: stdio-based convenience library for opening/seeking/decoding - last mod: $Id: vorbisfile.c,v 1.6.2.5 2003/11/20 06:16:17 xiphmont Exp $ - - ********************************************************************/ - -#include <stdlib.h> -#include <stdio.h> -//#include <errno.h> -#include <string.h> -#include <math.h> - -#include "codec_internal.h" -#include "ivorbisfile.h" - -#include "os.h" -#include "misc.h" - -int errno; - -#define NOTOPEN 0 -#define PARTOPEN 1 -#define OPENED 2 -#define STREAMSET 3 /* serialno and link set, but not to current link */ -#define LINKSET 4 /* serialno and link set to current link */ -#define INITSET 5 - -/* A 'chained bitstream' is a Vorbis bitstream that contains more than - one logical bitstream arranged end to end (the only form of Ogg - multiplexing allowed in a Vorbis bitstream; grouping [parallel - multiplexing] is not allowed in Vorbis) */ - -/* A Vorbis file can be played beginning to end (streamed) without - worrying ahead of time about chaining (see decoder_example.c). If - we have the whole file, however, and want random access - (seeking/scrubbing) or desire to know the total length/time of a - file, we need to account for the possibility of chaining. */ - -/* We can handle things a number of ways; we can determine the entire - bitstream structure right off the bat, or find pieces on demand. - This example determines and caches structure for the entire - bitstream, but builds a virtual decoder on the fly when moving - between links in the chain. */ - -/* There are also different ways to implement seeking. Enough - information exists in an Ogg bitstream to seek to - sample-granularity positions in the output. Or, one can seek by - picking some portion of the stream roughly in the desired area if - we only want coarse navigation through the stream. */ - -/************************************************************************* - * Many, many internal helpers. The intention is not to be confusing; - * rampant duplication and monolithic function implementation would be - * harder to understand anyway. The high level functions are last. Begin - * grokking near the end of the file */ - - -/* read a little more data from the file/pipe into the ogg_sync framer */ -static long _get_data(OggVorbis_File *vf){ - errno=0; - if(vf->datasource){ - unsigned char *buffer=ogg_sync_bufferin(vf->oy,CHUNKSIZE); - long bytes=(vf->callbacks.read_func)(buffer,1,CHUNKSIZE,vf->datasource); - if(bytes>0)ogg_sync_wrote(vf->oy,bytes); - if(bytes==0 && errno)return -1; - return bytes; - }else - return 0; -} - -/* save a tiny smidge of verbosity to make the code more readable */ -static void _seek_helper(OggVorbis_File *vf,ogg_int64_t offset){ - if(vf->datasource){ - (vf->callbacks.seek_func)(vf->datasource, offset, SEEK_SET); - vf->offset=offset; - ogg_sync_reset(vf->oy); - }else{ - /* shouldn't happen unless someone writes a broken callback */ - return; - } -} - -/* The read/seek functions track absolute position within the stream */ - -/* from the head of the stream, get the next page. boundary specifies - if the function is allowed to fetch more data from the stream (and - how much) or only use internally buffered data. - - boundary: -1) unbounded search - 0) read no additional data; use cached only - n) search for a new page beginning for n bytes - - return: <0) did not find a page (OV_FALSE, OV_EOF, OV_EREAD) - n) found a page at absolute offset n - - produces a refcounted page */ - -static ogg_int64_t _get_next_page(OggVorbis_File *vf,ogg_page *og, - ogg_int64_t boundary){ - if(boundary>0)boundary+=vf->offset; - while(1){ - long more; - - if(boundary>0 && vf->offset>=boundary)return OV_FALSE; - more=ogg_sync_pageseek(vf->oy,og); - - if(more<0){ - /* skipped n bytes */ - vf->offset-=more; - }else{ - if(more==0){ - /* send more paramedics */ - if(!boundary)return OV_FALSE; - { - long ret=_get_data(vf); - if(ret==0)return OV_EOF; - if(ret<0)return OV_EREAD; - } - }else{ - /* got a page. Return the offset at the page beginning, - advance the internal offset past the page end */ - ogg_int64_t ret=vf->offset; - vf->offset+=more; - return ret; - - } - } - } -} - -/* find the latest page beginning before the current stream cursor - position. Much dirtier than the above as Ogg doesn't have any - backward search linkage. no 'readp' as it will certainly have to - read. */ -/* returns offset or OV_EREAD, OV_FAULT and produces a refcounted page */ - -static ogg_int64_t _get_prev_page(OggVorbis_File *vf,ogg_page *og){ - ogg_int64_t begin=vf->offset; - ogg_int64_t end=begin; - ogg_int64_t ret; - ogg_int64_t offset=-1; - - while(offset==-1){ - begin-=CHUNKSIZE; - if(begin<0) - begin=0; - _seek_helper(vf,begin); - while(vf->offset<end){ - ret=_get_next_page(vf,og,end-vf->offset); - if(ret==OV_EREAD)return OV_EREAD; - if(ret<0){ - break; - }else{ - offset=ret; - } - } - } - - /* we have the offset. Actually snork and hold the page now */ - _seek_helper(vf,offset); - ret=_get_next_page(vf,og,CHUNKSIZE); - if(ret<0) - /* this shouldn't be possible */ - return OV_EFAULT; - - return offset; -} - -/* finds each bitstream link one at a time using a bisection search - (has to begin by knowing the offset of the lb's initial page). - Recurses for each link so it can alloc the link storage after - finding them all, then unroll and fill the cache at the same time */ -static int _bisect_forward_serialno(OggVorbis_File *vf, - ogg_int64_t begin, - ogg_int64_t searched, - ogg_int64_t end, - ogg_uint32_t currentno, - long m){ - ogg_int64_t endsearched=end; - ogg_int64_t next=end; - ogg_page og={0,0,0,0}; - ogg_int64_t ret; - - /* the below guards against garbage seperating the last and - first pages of two links. */ - while(searched<endsearched){ - ogg_int64_t bisect; - - if(endsearched-searched<CHUNKSIZE){ - bisect=searched; - }else{ - bisect=(searched+endsearched)/2; - } - - _seek_helper(vf,bisect); - ret=_get_next_page(vf,&og,-1); - if(ret==OV_EREAD)return OV_EREAD; - if(ret<0 || ogg_page_serialno(&og)!=currentno){ - endsearched=bisect; - if(ret>=0)next=ret; - }else{ - searched=ret+og.header_len+og.body_len; - } - ogg_page_release(&og); - } - - _seek_helper(vf,next); - ret=_get_next_page(vf,&og,-1); - if(ret==OV_EREAD)return OV_EREAD; - - if(searched>=end || ret<0){ - ogg_page_release(&og); - vf->links=m+1; - vf->offsets=_ogg_malloc((vf->links+1)*sizeof(*vf->offsets)); - vf->serialnos=_ogg_malloc(vf->links*sizeof(*vf->serialnos)); - vf->offsets[m+1]=searched; - }else{ - ret=_bisect_forward_serialno(vf,next,vf->offset, - end,ogg_page_serialno(&og),m+1); - ogg_page_release(&og); - if(ret==OV_EREAD)return OV_EREAD; - } - - vf->offsets[m]=begin; - vf->serialnos[m]=currentno; - return 0; -} - -static int _decode_clear(OggVorbis_File *vf){ - if(vf->ready_state==INITSET){ - vorbis_dsp_destroy(vf->vd); - vf->vd=0; - vf->ready_state=STREAMSET; - } - - if(vf->ready_state>=STREAMSET){ - vorbis_info_clear(&vf->vi); - vorbis_comment_clear(&vf->vc); - vf->ready_state=OPENED; - } - return 0; -} - -/* uses the local ogg_stream storage in vf; this is important for - non-streaming input sources */ -/* consumes the page that's passed in (if any) */ -/* state is LINKSET upon successful return */ - -static int _fetch_headers(OggVorbis_File *vf, - vorbis_info *vi, - vorbis_comment *vc, - ogg_uint32_t *serialno, - ogg_page *og_ptr){ - ogg_page og={0,0,0,0}; - ogg_packet op={0,0,0,0,0,0}; - int i,ret; - - if(vf->ready_state>OPENED)_decode_clear(vf); - - if(!og_ptr){ - ogg_int64_t llret=_get_next_page(vf,&og,CHUNKSIZE); - if(llret==OV_EREAD)return OV_EREAD; - if(llret<0)return OV_ENOTVORBIS; - og_ptr=&og; - } - - ogg_stream_reset_serialno(vf->os,ogg_page_serialno(og_ptr)); - if(serialno)*serialno=vf->os->serialno; - - /* extract the initial header from the first page and verify that the - Ogg bitstream is in fact Vorbis data */ - - vorbis_info_init(vi); - vorbis_comment_init(vc); - - i=0; - while(i<3){ - ogg_stream_pagein(vf->os,og_ptr); - while(i<3){ - int result=ogg_stream_packetout(vf->os,&op); - if(result==0)break; - if(result==-1){ - ret=OV_EBADHEADER; - goto bail_header; - } - if((ret=vorbis_dsp_headerin(vi,vc,&op))){ - goto bail_header; - } - i++; - } - if(i<3) - if(_get_next_page(vf,og_ptr,CHUNKSIZE)<0){ - ret=OV_EBADHEADER; - goto bail_header; - } - } - - ogg_packet_release(&op); - ogg_page_release(&og); - vf->ready_state=LINKSET; - return 0; - - bail_header: - ogg_packet_release(&op); - ogg_page_release(&og); - vorbis_info_clear(vi); - vorbis_comment_clear(vc); - vf->ready_state=OPENED; - - return ret; -} - -/* we no longer preload all vorbis_info (and the associated - codec_setup) structs. Call this to seek and fetch the info from - the bitstream, if needed */ -static int _set_link_number(OggVorbis_File *vf,int link){ - if(link != vf->current_link) _decode_clear(vf); - if(vf->ready_state<STREAMSET){ - _seek_helper(vf,vf->offsets[link]); - ogg_stream_reset_serialno(vf->os,vf->serialnos[link]); - vf->current_serialno=vf->serialnos[link]; - vf->current_link=link; - return _fetch_headers(vf,&vf->vi,&vf->vc,&vf->current_serialno,NULL); - } - return 0; -} - -static int _set_link_number_preserve_pos(OggVorbis_File *vf,int link){ - ogg_int64_t pos=vf->offset; - int ret=_set_link_number(vf,link); - if(ret)return ret; - _seek_helper(vf,pos); - if(pos<vf->offsets[link] || pos>=vf->offsets[link+1]) - vf->ready_state=STREAMSET; - return 0; -} - -/* last step of the OggVorbis_File initialization; get all the offset - positions. Only called by the seekable initialization (local - stream storage is hacked slightly; pay attention to how that's - done) */ - -/* this is void and does not propogate errors up because we want to be - able to open and use damaged bitstreams as well as we can. Just - watch out for missing information for links in the OggVorbis_File - struct */ -static void _prefetch_all_offsets(OggVorbis_File *vf, ogg_int64_t dataoffset){ - ogg_page og={0,0,0,0}; - int i; - ogg_int64_t ret; - - vf->dataoffsets=_ogg_malloc(vf->links*sizeof(*vf->dataoffsets)); - vf->pcmlengths=_ogg_malloc(vf->links*2*sizeof(*vf->pcmlengths)); - - for(i=0;i<vf->links;i++){ - if(i==0){ - /* we already grabbed the initial header earlier. Just set the offset */ - vf->dataoffsets[i]=dataoffset; - _seek_helper(vf,dataoffset); - - }else{ - - /* seek to the location of the initial header */ - - _seek_helper(vf,vf->offsets[i]); - if(_fetch_headers(vf,&vf->vi,&vf->vc,NULL,NULL)<0){ - vf->dataoffsets[i]=-1; - }else{ - vf->dataoffsets[i]=vf->offset; - } - } - - /* fetch beginning PCM offset */ - - if(vf->dataoffsets[i]!=-1){ - ogg_int64_t accumulated=0,pos; - long lastblock=-1; - int result; - - ogg_stream_reset_serialno(vf->os,vf->serialnos[i]); - - while(1){ - ogg_packet op={0,0,0,0,0,0}; - - ret=_get_next_page(vf,&og,-1); - if(ret<0) - /* this should not be possible unless the file is - truncated/mangled */ - break; - - if(ogg_page_serialno(&og)!=vf->serialnos[i]) - break; - - pos=ogg_page_granulepos(&og); - - /* count blocksizes of all frames in the page */ - ogg_stream_pagein(vf->os,&og); - while((result=ogg_stream_packetout(vf->os,&op))){ - if(result>0){ /* ignore holes */ - long thisblock=vorbis_packet_blocksize(&vf->vi,&op); - if(lastblock!=-1) - accumulated+=(lastblock+thisblock)>>2; - lastblock=thisblock; - } - } - ogg_packet_release(&op); - - if(pos!=-1){ - /* pcm offset of last packet on the first audio page */ - accumulated= pos-accumulated; - break; - } - } - - /* less than zero? This is a stream with samples trimmed off - the beginning, a normal occurrence; set the offset to zero */ - if(accumulated<0)accumulated=0; - - vf->pcmlengths[i*2]=accumulated; - } - - /* get the PCM length of this link. To do this, - get the last page of the stream */ - { - ogg_int64_t end=vf->offsets[i+1]; - _seek_helper(vf,end); - - while(1){ - ret=_get_prev_page(vf,&og); - if(ret<0){ - /* this should not be possible */ - vorbis_info_clear(&vf->vi); - vorbis_comment_clear(&vf->vc); - break; - } - if(ogg_page_granulepos(&og)!=-1){ - vf->pcmlengths[i*2+1]=ogg_page_granulepos(&og)-vf->pcmlengths[i*2]; - break; - } - vf->offset=ret; - } - } - } - ogg_page_release(&og); -} - -static int _make_decode_ready(OggVorbis_File *vf){ - int i; - switch(vf->ready_state){ - case OPENED: - case STREAMSET: - for(i=0;i<vf->links;i++) - if(vf->offsets[i+1]>=vf->offset)break; - if(i==vf->links)return -1; - i=_set_link_number_preserve_pos(vf,i); - if(i)return i; - /* fall through */ - case LINKSET: - vf->vd=vorbis_dsp_create(&vf->vi); - vf->ready_state=INITSET; - vf->bittrack=0; - vf->samptrack=0; - case INITSET: - return 0; - default: - return -1; - } - -} - -static int _open_seekable2(OggVorbis_File *vf){ - ogg_uint32_t serialno=vf->current_serialno; - ogg_uint32_t tempserialno; - ogg_int64_t dataoffset=vf->offset, end; - ogg_page og={0,0,0,0}; - - /* we're partially open and have a first link header state in - storage in vf */ - /* we can seek, so set out learning all about this file */ - (vf->callbacks.seek_func)(vf->datasource,0,SEEK_END); - vf->offset=vf->end=(vf->callbacks.tell_func)(vf->datasource); - - /* We get the offset for the last page of the physical bitstream. - Most OggVorbis files will contain a single logical bitstream */ - end=_get_prev_page(vf,&og); - if(end<0)return (int)end; - - /* more than one logical bitstream? */ - tempserialno=ogg_page_serialno(&og); - ogg_page_release(&og); - - if(tempserialno!=serialno){ - - /* Chained bitstream. Bisect-search each logical bitstream - section. Do so based on serial number only */ - if(_bisect_forward_serialno(vf,0,0,end+1,serialno,0)<0)return OV_EREAD; - - }else{ - - /* Only one logical bitstream */ - if(_bisect_forward_serialno(vf,0,end,end+1,serialno,0))return OV_EREAD; - - } - - /* the initial header memory is referenced by vf after; don't free it */ - _prefetch_all_offsets(vf,dataoffset); - return ov_raw_seek(vf,0); -} - -/* fetch and process a packet. Handles the case where we're at a - bitstream boundary and dumps the decoding machine. If the decoding - machine is unloaded, it loads it. It also keeps pcm_offset up to - date (seek and read both use this. seek uses a special hack with - readp). - - return: <0) error, OV_HOLE (lost packet) or OV_EOF - 0) need more data (only if readp==0) - 1) got a packet -*/ - -static int _fetch_and_process_packet(OggVorbis_File *vf, - int readp, - int spanp){ - ogg_page og={0,0,0,0}; - ogg_packet op={0,0,0,0,0,0}; - int ret=0; - - /* handle one packet. Try to fetch it from current stream state */ - /* extract packets from page */ - while(1){ - - /* process a packet if we can. If the machine isn't loaded, - neither is a page */ - if(vf->ready_state==INITSET){ - while(1) { - int result=ogg_stream_packetout(vf->os,&op); - ogg_int64_t granulepos; - - if(result<0){ - ret=OV_HOLE; /* hole in the data. */ - goto cleanup; - } - if(result>0){ - /* got a packet. process it */ - granulepos=op.granulepos; - if(!vorbis_dsp_synthesis(vf->vd,&op,1)){ /* lazy check for lazy - header handling. The - header packets aren't - audio, so if/when we - submit them, - vorbis_synthesis will - reject them */ - - vf->samptrack+=vorbis_dsp_pcmout(vf->vd,NULL,0); - vf->bittrack+=op.bytes*8; - - /* update the pcm offset. */ - if(granulepos!=-1 && !op.e_o_s){ - int link=(vf->seekable?vf->current_link:0); - int i,samples; - - /* this packet has a pcm_offset on it (the last packet - completed on a page carries the offset) After processing - (above), we know the pcm position of the *last* sample - ready to be returned. Find the offset of the *first* - - As an aside, this trick is inaccurate if we begin - reading anew right at the last page; the end-of-stream - granulepos declares the last frame in the stream, and the - last packet of the last page may be a partial frame. - So, we need a previous granulepos from an in-sequence page - to have a reference point. Thus the !op.e_o_s clause - above */ - - if(vf->seekable && link>0) - granulepos-=vf->pcmlengths[link*2]; - if(granulepos<0)granulepos=0; /* actually, this - shouldn't be possible - here unless the stream - is very broken */ - - samples=vorbis_dsp_pcmout(vf->vd,NULL,0); - - granulepos-=samples; - for(i=0;i<link;i++) - granulepos+=vf->pcmlengths[i*2+1]; - vf->pcm_offset=granulepos; - } - ret=1; - goto cleanup; - } - } - else - break; - } - } - - if(vf->ready_state>=OPENED){ - int ret; - if(!readp){ - ret=0; - goto cleanup; - } - ret=(int)_get_next_page(vf,&og,-1); - if(ret<0){ - ret=OV_EOF; /* eof. leave unitialized */ - goto cleanup; - } - - /* bitrate tracking; add the header's bytes here, the body bytes - are done by packet above */ - vf->bittrack+=og.header_len*8; - - /* has our decoding just traversed a bitstream boundary? */ - if(vf->ready_state==INITSET){ - if(vf->current_serialno!=ogg_page_serialno(&og)){ - if(!spanp){ - ret=OV_EOF; - goto cleanup; - } - - _decode_clear(vf); - } - } - } - - /* Do we need to load a new machine before submitting the page? */ - /* This is different in the seekable and non-seekable cases. - - In the seekable case, we already have all the header - information loaded and cached; we just initialize the machine - with it and continue on our merry way. - - In the non-seekable (streaming) case, we'll only be at a - boundary if we just left the previous logical bitstream and - we're now nominally at the header of the next bitstream - */ - - if(vf->ready_state!=INITSET){ - int link,ret; - - if(vf->ready_state<STREAMSET){ - if(vf->seekable){ - vf->current_serialno=ogg_page_serialno(&og); - - /* match the serialno to bitstream section. We use this rather than - offset positions to avoid problems near logical bitstream - boundaries */ - for(link=0;link<vf->links;link++) - if(vf->serialnos[link]==vf->current_serialno)break; - if(link==vf->links){ - ret=OV_EBADLINK; /* sign of a bogus stream. error out, - leave machine uninitialized */ - goto cleanup; - } - - vf->current_link=link; - ret=_fetch_headers(vf,&vf->vi,&vf->vc,&vf->current_serialno,&og); - if(ret) goto cleanup; - - }else{ - /* we're streaming */ - /* fetch the three header packets, build the info struct */ - - int ret=_fetch_headers(vf,&vf->vi,&vf->vc,&vf->current_serialno,&og); - if(ret) goto cleanup; - vf->current_link++; - } - } - - if(_make_decode_ready(vf)) return OV_EBADLINK; - } - ogg_stream_pagein(vf->os,&og); - } - cleanup: - ogg_packet_release(&op); - ogg_page_release(&og); - return ret; -} - -/* if, eg, 64 bit stdio is configured by default, this will build with - fseek64 */ -static int _fseek64_wrap(FILE *f,ogg_int64_t off,int whence){ - if(f==NULL)return -1; - return fseek(f,(long)off,whence); -} - -static int _ov_open1(void *f,OggVorbis_File *vf,char *initial, - long ibytes, ov_callbacks callbacks){ - int offsettest=(f?callbacks.seek_func(f,0,SEEK_CUR):-1); - int ret; - - memset(vf,0,sizeof(*vf)); - - /* Tremor assumes in multiple places that right shift of a signed - integer is an arithmetic shift */ - if( (-1>>1) != -1) return OV_EIMPL; - - vf->datasource=f; - vf->callbacks = callbacks; - - /* init the framing state */ - vf->oy=ogg_sync_create(); - - /* perhaps some data was previously read into a buffer for testing - against other stream types. Allow initialization from this - previously read data (as we may be reading from a non-seekable - stream) */ - if(initial){ - unsigned char *buffer=ogg_sync_bufferin(vf->oy,ibytes); - memcpy(buffer,initial,ibytes); - ogg_sync_wrote(vf->oy,ibytes); - } - - /* can we seek? Stevens suggests the seek test was portable */ - if(offsettest!=-1)vf->seekable=1; - - /* No seeking yet; Set up a 'single' (current) logical bitstream - entry for partial open */ - vf->links=1; - vf->os=ogg_stream_create(-1); /* fill in the serialno later */ - - /* Try to fetch the headers, maintaining all the storage */ - if((ret=_fetch_headers(vf,&vf->vi,&vf->vc,&vf->current_serialno,NULL))<0){ - vf->datasource=NULL; - ov_clear(vf); - }else if(vf->ready_state < PARTOPEN) - vf->ready_state=PARTOPEN; - return ret; -} - -static int _ov_open2(OggVorbis_File *vf){ - if(vf->ready_state < OPENED) - vf->ready_state=OPENED; - if(vf->seekable){ - int ret=_open_seekable2(vf); - if(ret){ - vf->datasource=NULL; - ov_clear(vf); - } - return ret; - } - return 0; -} - - -/* clear out the OggVorbis_File struct */ -int ov_clear(OggVorbis_File *vf){ - if(vf){ - vorbis_dsp_destroy(vf->vd); - vf->vd=0; - ogg_stream_destroy(vf->os); - vorbis_info_clear(&vf->vi); - vorbis_comment_clear(&vf->vc); - if(vf->dataoffsets)_ogg_free(vf->dataoffsets); - if(vf->pcmlengths)_ogg_free(vf->pcmlengths); - if(vf->serialnos)_ogg_free(vf->serialnos); - if(vf->offsets)_ogg_free(vf->offsets); - ogg_sync_destroy(vf->oy); - - if(vf->datasource)(vf->callbacks.close_func)(vf->datasource); - memset(vf,0,sizeof(*vf)); - } -#ifdef DEBUG_LEAKS - _VDBG_dump(); -#endif - return 0; -} - -/* inspects the OggVorbis file and finds/documents all the logical - bitstreams contained in it. Tries to be tolerant of logical - bitstream sections that are truncated/woogie. - - return: -1) error - 0) OK -*/ - -int ov_open_callbacks(void *f,OggVorbis_File *vf,char *initial,long ibytes, - ov_callbacks callbacks){ - int ret=_ov_open1(f,vf,initial,ibytes,callbacks); - if(ret)return ret; - return _ov_open2(vf); -} - -int ov_open(FILE *f,OggVorbis_File *vf,char *initial,long ibytes){ - ov_callbacks callbacks = { - (size_t (*)(void *, size_t, size_t, void *)) fread, - (int (*)(void *, ogg_int64_t, int)) _fseek64_wrap, - (int (*)(void *)) fclose, - (long (*)(void *)) ftell - }; - - return ov_open_callbacks((void *)f, vf, initial, ibytes, callbacks); -} - -/* Only partially open the vorbis file; test for Vorbisness, and load - the headers for the first chain. Do not seek (although test for - seekability). Use ov_test_open to finish opening the file, else - ov_clear to close/free it. Same return codes as open. */ - -int ov_test_callbacks(void *f,OggVorbis_File *vf,char *initial,long ibytes, - ov_callbacks callbacks) -{ - return _ov_open1(f,vf,initial,ibytes,callbacks); -} - -int ov_test(FILE *f,OggVorbis_File *vf,char *initial,long ibytes){ - ov_callbacks callbacks = { - (size_t (*)(void *, size_t, size_t, void *)) fread, - (int (*)(void *, ogg_int64_t, int)) _fseek64_wrap, - (int (*)(void *)) fclose, - (long (*)(void *)) ftell - }; - - return ov_test_callbacks((void *)f, vf, initial, ibytes, callbacks); -} - -int ov_test_open(OggVorbis_File *vf){ - if(vf->ready_state!=PARTOPEN)return OV_EINVAL; - return _ov_open2(vf); -} - -/* How many logical bitstreams in this physical bitstream? */ -long ov_streams(OggVorbis_File *vf){ - return vf->links; -} - -/* Is the FILE * associated with vf seekable? */ -long ov_seekable(OggVorbis_File *vf){ - return vf->seekable; -} - -/* returns the bitrate for a given logical bitstream or the entire - physical bitstream. If the file is open for random access, it will - find the *actual* average bitrate. If the file is streaming, it - returns the nominal bitrate (if set) else the average of the - upper/lower bounds (if set) else -1 (unset). - - If you want the actual bitrate field settings, get them from the - vorbis_info structs */ - -long ov_bitrate(OggVorbis_File *vf,int i){ - if(vf->ready_state<OPENED)return OV_EINVAL; - if(i>=vf->links)return OV_EINVAL; - if(!vf->seekable && i!=0)return ov_bitrate(vf,0); - if(i<0){ - ogg_int64_t bits=0; - int i; - for(i=0;i<vf->links;i++) - bits+=(vf->offsets[i+1]-vf->dataoffsets[i])*8; - /* This once read: return(rint(bits/ov_time_total(vf,-1))); - * gcc 3.x on x86 miscompiled this at optimisation level 2 and above, - * so this is slightly transformed to make it work. - */ - return (long)(bits*1000/ov_time_total(vf,-1)); - }else{ - if(vf->seekable){ - /* return the actual bitrate */ - return (long)((vf->offsets[i+1]-vf->dataoffsets[i])*8000/ov_time_total(vf,i)); - }else{ - /* return nominal if set */ - if(vf->vi.bitrate_nominal>0){ - return vf->vi.bitrate_nominal; - }else{ - if(vf->vi.bitrate_upper>0){ - if(vf->vi.bitrate_lower>0){ - return (vf->vi.bitrate_upper+vf->vi.bitrate_lower)/2; - }else{ - return vf->vi.bitrate_upper; - } - } - return OV_FALSE; - } - } - } -} - -/* returns the actual bitrate since last call. returns -1 if no - additional data to offer since last call (or at beginning of stream), - EINVAL if stream is only partially open -*/ -long ov_bitrate_instant(OggVorbis_File *vf){ - long ret; - if(vf->ready_state<OPENED)return OV_EINVAL; - if(vf->samptrack==0)return OV_FALSE; - ret=(long)(vf->bittrack/vf->samptrack*vf->vi.rate); - vf->bittrack=0; - vf->samptrack=0; - return ret; -} - -/* Guess */ -long ov_serialnumber(OggVorbis_File *vf,int i){ - if(i>=vf->links)return ov_serialnumber(vf,vf->links-1); - if(!vf->seekable && i>=0)return ov_serialnumber(vf,-1); - if(i<0){ - return vf->current_serialno; - }else{ - return vf->serialnos[i]; - } -} - -/* returns: total raw (compressed) length of content if i==-1 - raw (compressed) length of that logical bitstream for i==0 to n - OV_EINVAL if the stream is not seekable (we can't know the length) - or if stream is only partially open -*/ -ogg_int64_t ov_raw_total(OggVorbis_File *vf,int i){ - if(vf->ready_state<OPENED)return OV_EINVAL; - if(!vf->seekable || i>=vf->links)return OV_EINVAL; - if(i<0){ - ogg_int64_t acc=0; - int i; - for(i=0;i<vf->links;i++) - acc+=ov_raw_total(vf,i); - return acc; - }else{ - return vf->offsets[i+1]-vf->offsets[i]; - } -} - -/* returns: total PCM length (samples) of content if i==-1 PCM length - (samples) of that logical bitstream for i==0 to n - OV_EINVAL if the stream is not seekable (we can't know the - length) or only partially open -*/ -ogg_int64_t ov_pcm_total(OggVorbis_File *vf,int i){ - if(vf->ready_state<OPENED)return OV_EINVAL; - if(!vf->seekable || i>=vf->links)return OV_EINVAL; - if(i<0){ - ogg_int64_t acc=0; - int i; - for(i=0;i<vf->links;i++) - acc+=ov_pcm_total(vf,i); - return acc; - }else{ - return vf->pcmlengths[i*2+1]; - } -} - -/* returns: total milliseconds of content if i==-1 - milliseconds in that logical bitstream for i==0 to n - OV_EINVAL if the stream is not seekable (we can't know the - length) or only partially open -*/ -ogg_int64_t ov_time_total(OggVorbis_File *vf,int i){ - if(vf->ready_state<OPENED)return OV_EINVAL; - if(!vf->seekable || i>=vf->links)return OV_EINVAL; - if(i<0){ - ogg_int64_t acc=0; - int i; - for(i=0;i<vf->links;i++) - acc+=ov_time_total(vf,i); - return acc; - }else{ - return ((ogg_int64_t)vf->pcmlengths[i*2+1])*1000/vf->vi.rate; - } -} - -/* seek to an offset relative to the *compressed* data. This also - scans packets to update the PCM cursor. It will cross a logical - bitstream boundary, but only if it can't get any packets out of the - tail of the bitstream we seek to (so no surprises). - - returns zero on success, nonzero on failure */ - -int ov_raw_seek(OggVorbis_File *vf,ogg_int64_t pos){ - ogg_stream_state *work_os=NULL; - ogg_page og={0,0,0,0}; - ogg_packet op={0,0,0,0,0,0}; - - if(vf->ready_state<OPENED)return OV_EINVAL; - if(!vf->seekable) - return OV_ENOSEEK; /* don't dump machine if we can't seek */ - - if(pos<0 || pos>vf->end)return OV_EINVAL; - - /* don't yet clear out decoding machine (if it's initialized), in - the case we're in the same link. Restart the decode lapping, and - let _fetch_and_process_packet deal with a potential bitstream - boundary */ - vf->pcm_offset=-1; - ogg_stream_reset_serialno(vf->os, - vf->current_serialno); /* must set serialno */ - vorbis_dsp_restart(vf->vd); - - _seek_helper(vf,pos); - - /* we need to make sure the pcm_offset is set, but we don't want to - advance the raw cursor past good packets just to get to the first - with a granulepos. That's not equivalent behavior to beginning - decoding as immediately after the seek position as possible. - - So, a hack. We use two stream states; a local scratch state and - the shared vf->os stream state. We use the local state to - scan, and the shared state as a buffer for later decode. - - Unfortuantely, on the last page we still advance to last packet - because the granulepos on the last page is not necessarily on a - packet boundary, and we need to make sure the granpos is - correct. - */ - - { - int lastblock=0; - int accblock=0; - int thisblock; - int eosflag; - - work_os=ogg_stream_create(vf->current_serialno); /* get the memory ready */ - while(1){ - if(vf->ready_state>=STREAMSET){ - /* snarf/scan a packet if we can */ - int result=ogg_stream_packetout(work_os,&op); - - if(result>0){ - - if(vf->vi.codec_setup){ - thisblock=vorbis_packet_blocksize(&vf->vi,&op); - if(thisblock<0){ - ogg_stream_packetout(vf->os,NULL); - thisblock=0; - }else{ - - if(eosflag) - ogg_stream_packetout(vf->os,NULL); - else - if(lastblock)accblock+=(lastblock+thisblock)>>2; - } - - if(op.granulepos!=-1){ - int i,link=vf->current_link; - ogg_int64_t granulepos=op.granulepos-vf->pcmlengths[link*2]; - if(granulepos<0)granulepos=0; - - for(i=0;i<link;i++) - granulepos+=vf->pcmlengths[i*2+1]; - vf->pcm_offset=granulepos-accblock; - break; - } - lastblock=thisblock; - continue; - }else - ogg_stream_packetout(vf->os,NULL); - } - } - - if(!lastblock){ - if(_get_next_page(vf,&og,-1)<0){ - vf->pcm_offset=ov_pcm_total(vf,-1); - break; - } - }else{ - /* huh? Bogus stream with packets but no granulepos */ - vf->pcm_offset=-1; - break; - } - - /* did we just grab a page from other than current link? */ - if(vf->ready_state>=STREAMSET) - if(vf->current_serialno!=ogg_page_serialno(&og)){ - _decode_clear(vf); /* clear out stream state */ - ogg_stream_destroy(work_os); - } - - if(vf->ready_state<STREAMSET){ - int link; - - vf->current_serialno=ogg_page_serialno(&og); - for(link=0;link<vf->links;link++) - if(vf->serialnos[link]==vf->current_serialno)break; - if(link==vf->links) - goto seek_error; /* sign of a bogus stream. error out, - leave machine uninitialized */ - - /* need to initialize machine to this link */ - { - int ret=_set_link_number_preserve_pos(vf,link); - if(ret) goto seek_error; - } - ogg_stream_reset_serialno(vf->os,vf->current_serialno); - ogg_stream_reset_serialno(work_os,vf->current_serialno); - - - } - - { - ogg_page dup; - ogg_page_dup(&dup,&og); - eosflag=ogg_page_eos(&og); - ogg_stream_pagein(vf->os,&og); - ogg_stream_pagein(work_os,&dup); - } - } - } - - ogg_packet_release(&op); - ogg_page_release(&og); - ogg_stream_destroy(work_os); - vf->bittrack=0; - vf->samptrack=0; - return 0; - - seek_error: - ogg_packet_release(&op); - ogg_page_release(&og); - - /* dump the machine so we're in a known state */ - vf->pcm_offset=-1; - ogg_stream_destroy(work_os); - _decode_clear(vf); - return OV_EBADLINK; -} - -/* Page granularity seek (faster than sample granularity because we - don't do the last bit of decode to find a specific sample). - - Seek to the last [granule marked] page preceeding the specified pos - location, such that decoding past the returned point will quickly - arrive at the requested position. */ -int ov_pcm_seek_page(OggVorbis_File *vf,ogg_int64_t pos){ - int link=-1; - ogg_int64_t result=0; - ogg_int64_t total=ov_pcm_total(vf,-1); - ogg_page og={0,0,0,0}; - ogg_packet op={0,0,0,0,0,0}; - - if(vf->ready_state<OPENED)return OV_EINVAL; - if(!vf->seekable)return OV_ENOSEEK; - if(pos<0 || pos>total)return OV_EINVAL; - - /* which bitstream section does this pcm offset occur in? */ - for(link=vf->links-1;link>=0;link--){ - total-=vf->pcmlengths[link*2+1]; - if(pos>=total)break; - } - - - if(link!=vf->current_link){ - int ret=_set_link_number(vf,link); - if(ret) goto seek_error; - }else{ - vorbis_dsp_restart(vf->vd); - } - - ogg_stream_reset_serialno(vf->os,vf->serialnos[link]); - - /* search within the logical bitstream for the page with the highest - pcm_pos preceeding (or equal to) pos. There is a danger here; - missing pages or incorrect frame number information in the - bitstream could make our task impossible. Account for that (it - would be an error condition) */ - - /* new search algorithm by HB (Nicholas Vinen) */ - { - ogg_int64_t end=vf->offsets[link+1]; - ogg_int64_t begin=vf->offsets[link]; - ogg_int64_t begintime = vf->pcmlengths[link*2]; - ogg_int64_t endtime = vf->pcmlengths[link*2+1]+begintime; - ogg_int64_t target=pos-total+begintime; - ogg_int64_t best=begin; - - while(begin<end){ - ogg_int64_t bisect; - - if(end-begin<CHUNKSIZE){ - bisect=begin; - }else{ - /* take a (pretty decent) guess. */ - bisect=begin + - (target-begintime)*(end-begin)/(endtime-begintime) - CHUNKSIZE; - if(bisect<=begin) - bisect=begin+1; - } - - _seek_helper(vf,bisect); - - while(begin<end){ - result=_get_next_page(vf,&og,end-vf->offset); - if(result==OV_EREAD) goto seek_error; - if(result<0){ - if(bisect<=begin+1) - end=begin; /* found it */ - else{ - if(bisect==0) goto seek_error; - bisect-=CHUNKSIZE; - if(bisect<=begin)bisect=begin+1; - _seek_helper(vf,bisect); - } - }else{ - ogg_int64_t granulepos=ogg_page_granulepos(&og); - if(granulepos==-1)continue; - if(granulepos<target){ - best=result; /* raw offset of packet with granulepos */ - begin=vf->offset; /* raw offset of next page */ - begintime=granulepos; - - if(target-begintime>44100)break; - bisect=begin; /* *not* begin + 1 */ - }else{ - if(bisect<=begin+1) - end=begin; /* found it */ - else{ - if(end==vf->offset){ /* we're pretty close - we'd be stuck in */ - end=result; - bisect-=CHUNKSIZE; /* an endless loop otherwise. */ - if(bisect<=begin)bisect=begin+1; - _seek_helper(vf,bisect); - }else{ - end=result; - endtime=granulepos; - break; - } - } - } - } - } - } - - /* found our page. seek to it, update pcm offset. Easier case than - raw_seek, don't keep packets preceeding granulepos. */ - { - - /* seek */ - _seek_helper(vf,best); - vf->pcm_offset=-1; - - if(_get_next_page(vf,&og,-1)<0){ - ogg_page_release(&og); - return OV_EOF; /* shouldn't happen */ - } - - ogg_stream_pagein(vf->os,&og); - - /* pull out all but last packet; the one with granulepos */ - while(1){ - result=ogg_stream_packetpeek(vf->os,&op); - if(result==0){ - /* !!! the packet finishing this page originated on a - preceeding page. Keep fetching previous pages until we - get one with a granulepos or without the 'continued' flag - set. Then just use raw_seek for simplicity. */ - - _seek_helper(vf,best); - - while(1){ - result=_get_prev_page(vf,&og); - if(result<0) goto seek_error; - if(ogg_page_granulepos(&og)>-1 || - !ogg_page_continued(&og)){ - return ov_raw_seek(vf,result); - } - vf->offset=result; - } - } - if(result<0){ - result = OV_EBADPACKET; - goto seek_error; - } - if(op.granulepos!=-1){ - vf->pcm_offset=op.granulepos-vf->pcmlengths[vf->current_link*2]; - if(vf->pcm_offset<0)vf->pcm_offset=0; - vf->pcm_offset+=total; - break; - }else - result=ogg_stream_packetout(vf->os,NULL); - } - } - } - - /* verify result */ - if(vf->pcm_offset>pos || pos>ov_pcm_total(vf,-1)){ - result=OV_EFAULT; - goto seek_error; - } - vf->bittrack=0; - vf->samptrack=0; - - ogg_page_release(&og); - ogg_packet_release(&op); - return 0; - - seek_error: - - ogg_page_release(&og); - ogg_packet_release(&op); - - /* dump machine so we're in a known state */ - vf->pcm_offset=-1; - _decode_clear(vf); - return (int)result; -} - -/* seek to a sample offset relative to the decompressed pcm stream - returns zero on success, nonzero on failure */ - -int ov_pcm_seek(OggVorbis_File *vf,ogg_int64_t pos){ - ogg_packet op={0,0,0,0,0,0}; - ogg_page og={0,0,0,0}; - int thisblock,lastblock=0; - int ret=ov_pcm_seek_page(vf,pos); - if(ret<0)return ret; - if(_make_decode_ready(vf))return OV_EBADLINK; - - /* discard leading packets we don't need for the lapping of the - position we want; don't decode them */ - - while(1){ - - int ret=ogg_stream_packetpeek(vf->os,&op); - if(ret>0){ - thisblock=vorbis_packet_blocksize(&vf->vi,&op); - if(thisblock<0){ - ogg_stream_packetout(vf->os,NULL); - continue; /* non audio packet */ - } - if(lastblock)vf->pcm_offset+=(lastblock+thisblock)>>2; - - if(vf->pcm_offset+((thisblock+ - vorbis_info_blocksize(&vf->vi,1))>>2)>=pos)break; - - /* remove the packet from packet queue and track its granulepos */ - ogg_stream_packetout(vf->os,NULL); - vorbis_dsp_synthesis(vf->vd,&op,0); /* set up a vb with - only tracking, no - pcm_decode */ - - /* end of logical stream case is hard, especially with exact - length positioning. */ - - if(op.granulepos>-1){ - int i; - /* always believe the stream markers */ - vf->pcm_offset=op.granulepos-vf->pcmlengths[vf->current_link*2]; - if(vf->pcm_offset<0)vf->pcm_offset=0; - for(i=0;i<vf->current_link;i++) - vf->pcm_offset+=vf->pcmlengths[i*2+1]; - } - - lastblock=thisblock; - - }else{ - if(ret<0 && ret!=OV_HOLE)break; - - /* suck in a new page */ - if(_get_next_page(vf,&og,-1)<0)break; - if(vf->current_serialno!=ogg_page_serialno(&og))_decode_clear(vf); - - if(vf->ready_state<STREAMSET){ - int link,ret; - - vf->current_serialno=ogg_page_serialno(&og); - for(link=0;link<vf->links;link++) - if(vf->serialnos[link]==vf->current_serialno)break; - if(link==vf->links){ - ogg_page_release(&og); - ogg_packet_release(&op); - return OV_EBADLINK; - } - - - vf->current_link=link; - ret=_fetch_headers(vf,&vf->vi,&vf->vc,&vf->current_serialno,&og); - if(ret) return ret; - if(_make_decode_ready(vf))return OV_EBADLINK; - lastblock=0; - } - - ogg_stream_pagein(vf->os,&og); - } - } - - vf->bittrack=0; - vf->samptrack=0; - /* discard samples until we reach the desired position. Crossing a - logical bitstream boundary with abandon is OK. */ - while(vf->pcm_offset<pos){ - ogg_int64_t target=pos-vf->pcm_offset; - long samples=vorbis_dsp_pcmout(vf->vd,NULL,0); - - if(samples>target)samples=(long)target; - vorbis_dsp_read(vf->vd,samples); - vf->pcm_offset+=samples; - - if(samples<target) - if(_fetch_and_process_packet(vf,1,1)<=0) - vf->pcm_offset=ov_pcm_total(vf,-1); /* eof */ - } - - ogg_page_release(&og); - ogg_packet_release(&op); - return 0; -} - -/* seek to a playback time relative to the decompressed pcm stream - returns zero on success, nonzero on failure */ -int ov_time_seek(OggVorbis_File *vf,ogg_int64_t milliseconds){ - /* translate time to PCM position and call ov_pcm_seek */ - - int link=-1; - ogg_int64_t pcm_total=ov_pcm_total(vf,-1); - ogg_int64_t time_total=ov_time_total(vf,-1); - - if(vf->ready_state<OPENED)return OV_EINVAL; - if(!vf->seekable)return OV_ENOSEEK; - if(milliseconds<0 || milliseconds>time_total)return OV_EINVAL; - - /* which bitstream section does this time offset occur in? */ - for(link=vf->links-1;link>=0;link--){ - pcm_total-=vf->pcmlengths[link*2+1]; - time_total-=ov_time_total(vf,link); - if(milliseconds>=time_total)break; - } - - /* enough information to convert time offset to pcm offset */ - { - int ret=_set_link_number(vf,link); - if(ret)return ret; - return - ov_pcm_seek(vf,pcm_total+(milliseconds-time_total)* - vf->vi.rate/1000); - } -} - -/* page-granularity version of ov_time_seek - returns zero on success, nonzero on failure */ -int ov_time_seek_page(OggVorbis_File *vf,ogg_int64_t milliseconds){ - /* translate time to PCM position and call ov_pcm_seek */ - - int link=-1; - ogg_int64_t pcm_total=ov_pcm_total(vf,-1); - ogg_int64_t time_total=ov_time_total(vf,-1); - - if(vf->ready_state<OPENED)return OV_EINVAL; - if(!vf->seekable)return OV_ENOSEEK; - if(milliseconds<0 || milliseconds>time_total)return OV_EINVAL; - - /* which bitstream section does this time offset occur in? */ - for(link=vf->links-1;link>=0;link--){ - pcm_total-=vf->pcmlengths[link*2+1]; - time_total-=ov_time_total(vf,link); - if(milliseconds>=time_total)break; - } - - /* enough information to convert time offset to pcm offset */ - { - int ret=_set_link_number(vf,link); - if(ret)return ret; - return - ov_pcm_seek_page(vf,pcm_total+(milliseconds-time_total)* - vf->vi.rate/1000); - } -} - -/* tell the current stream offset cursor. Note that seek followed by - tell will likely not give the set offset due to caching */ -ogg_int64_t ov_raw_tell(OggVorbis_File *vf){ - if(vf->ready_state<OPENED)return OV_EINVAL; - return vf->offset; -} - -/* return PCM offset (sample) of next PCM sample to be read */ -ogg_int64_t ov_pcm_tell(OggVorbis_File *vf){ - if(vf->ready_state<OPENED)return OV_EINVAL; - return vf->pcm_offset; -} - -/* return time offset (milliseconds) of next PCM sample to be read */ -ogg_int64_t ov_time_tell(OggVorbis_File *vf){ - int link=0; - ogg_int64_t pcm_total=0; - ogg_int64_t time_total=0; - - if(vf->ready_state<OPENED)return OV_EINVAL; - if(vf->seekable){ - pcm_total=ov_pcm_total(vf,-1); - time_total=ov_time_total(vf,-1); - - /* which bitstream section does this time offset occur in? */ - for(link=vf->links-1;link>=0;link--){ - pcm_total-=vf->pcmlengths[link*2+1]; - time_total-=ov_time_total(vf,link); - if(vf->pcm_offset>=pcm_total)break; - } - } - - return time_total+(1000*vf->pcm_offset-pcm_total)/vf->vi.rate; -} - -/* link: -1) return the vorbis_info struct for the bitstream section - currently being decoded - 0-n) to request information for a specific bitstream section - - In the case of a non-seekable bitstream, any call returns the - current bitstream. NULL in the case that the machine is not - initialized */ - -vorbis_info *ov_info(OggVorbis_File *vf,int link){ - if(vf->seekable){ - if(link>=vf->links)return NULL; - if(link>=0){ - int ret=_set_link_number_preserve_pos(vf,link); - if(ret)return NULL; - } - } - return &vf->vi; -} - -/* grr, strong typing, grr, no templates/inheritence, grr */ -vorbis_comment *ov_comment(OggVorbis_File *vf,int link){ - if(vf->seekable){ - if(link>=vf->links)return NULL; - if(link>=0){ - int ret=_set_link_number_preserve_pos(vf,link); - if(ret)return NULL; - } - } - return &vf->vc; -} - -/* up to this point, everything could more or less hide the multiple - logical bitstream nature of chaining from the toplevel application - if the toplevel application didn't particularly care. However, at - the point that we actually read audio back, the multiple-section - nature must surface: Multiple bitstream sections do not necessarily - have to have the same number of channels or sampling rate. - - ov_read returns the sequential logical bitstream number currently - being decoded along with the PCM data in order that the toplevel - application can take action on channel/sample rate changes. This - number will be incremented even for streamed (non-seekable) streams - (for seekable streams, it represents the actual logical bitstream - index within the physical bitstream. Note that the accessor - functions above are aware of this dichotomy). - - input values: buffer) a buffer to hold packed PCM data for return - length) the byte length requested to be placed into buffer - - return values: <0) error/hole in data (OV_HOLE), partial open (OV_EINVAL) - 0) EOF - n) number of bytes of PCM actually returned. The - below works on a packet-by-packet basis, so the - return length is not related to the 'length' passed - in, just guaranteed to fit. - - *section) set to the logical bitstream number */ - -long ov_read(OggVorbis_File *vf,void *buffer,int bytes_req,int *bitstream){ - - long samples; - long channels; - - if(vf->ready_state<OPENED)return OV_EINVAL; - - while(1){ - if(vf->ready_state==INITSET){ - channels=vf->vi.channels; - samples=vorbis_dsp_pcmout(vf->vd,buffer,(bytes_req>>1)/channels); - if(samples){ - if(samples>0){ - vorbis_dsp_read(vf->vd,samples); - vf->pcm_offset+=samples; - if(bitstream)*bitstream=vf->current_link; - return samples*2*channels; - } - return samples; - } - } - - /* suck in another packet */ - { - int ret=_fetch_and_process_packet(vf,1,1); - if(ret==OV_EOF) - return 0; - if(ret<=0) - return ret; - } - - } -} |