From f40bfc9267b13b54e6379dfe7539447662879d24 Mon Sep 17 00:00:00 2001 From: Sean Bartell Date: Sat, 25 Jun 2011 21:32:25 -0400 Subject: Add codecs to librbcodec. MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Change-Id: Id7f4717d51ed02d67cb9f9cb3c0ada4a81843f97 Reviewed-on: http://gerrit.rockbox.org/137 Reviewed-by: Nils Wallménius Tested-by: Nils Wallménius --- lib/rbcodec/codecs/libtremor/vorbisfile.c | 1671 +++++++++++++++++++++++++++++ 1 file changed, 1671 insertions(+) create mode 100644 lib/rbcodec/codecs/libtremor/vorbisfile.c (limited to 'lib/rbcodec/codecs/libtremor/vorbisfile.c') diff --git a/lib/rbcodec/codecs/libtremor/vorbisfile.c b/lib/rbcodec/codecs/libtremor/vorbisfile.c new file mode 100644 index 0000000000..271e5a09e3 --- /dev/null +++ b/lib/rbcodec/codecs/libtremor/vorbisfile.c @@ -0,0 +1,1671 @@ +/******************************************************************** + * * + * 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: $Id$ + + ********************************************************************/ + +#include "config-tremor.h" +#include +#include +#include +#include +#include "system.h" + +#include "ivorbiscodec.h" +#include "ivorbisfile.h" + +#include "os.h" +#include "misc.h" + +/* 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){ + if(!(vf->callbacks.read_func))return(-1); + if(vf->datasource){ + char *buffer=ogg_sync_buffer(&vf->oy,CHUNKSIZE); + long bytes=(vf->callbacks.read_func)(buffer,1,CHUNKSIZE,vf->datasource); + if(bytes>0)ogg_sync_wrote(&vf->oy,bytes); + return(bytes); + }else + return(0); +} + +/* save a tiny smidge of verbosity to make the code more readable */ +static int _seek_helper(OggVorbis_File *vf,ogg_int64_t offset){ + if(vf->datasource){ + if(!(vf->callbacks.seek_func)|| + (vf->callbacks.seek_func)(vf->datasource, offset, SEEK_SET) == -1) + return OV_EREAD; + vf->offset=offset; + ogg_sync_reset(&vf->oy); + }else{ + /* shouldn't happen unless someone writes a broken callback */ + return OV_EFAULT; + } + return 0; +} + +/* 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 */ + +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); + + } + } + } +} + +/* This is a nasty hack to work around the huge allocations we get from + huge comment packets, usually due to embedded album art */ +static int ogg_stream_discard_packet(OggVorbis_File *vf,ogg_page *og, + ogg_int64_t boundary){ + int ret; + while((ret = ogg_stream_packetout(&vf->os, NULL)) == 0) { + if(_get_next_page(vf, og, boundary)<0) + break; + ogg_stream_pagein(&vf->os,og,false); + } + if (ret < 0) + return -1; + /* We might be pretending to have filled in more of the buffer than there is + actual space, in this case the body storage must be expanded before we + start writing to it */ + if (vf->os.body_fill < og->body_len || vf->os.body_storage < vf->os.body_fill) + if(_os_body_expand(&vf->os, vf->os.body_fill - vf->os.body_storage + og->body_len)) + return -1; + memcpy(vf->os.body_data+vf->os.body_fill-og->body_len, og->body, og->body_len); + return 1; +} + +/* 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 */ +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; + + ret=_seek_helper(vf,begin); + if(ret)return(ret); + + while(vf->offsetoffset); + if(ret==OV_EREAD)return(OV_EREAD); + if(ret<0){ + break; + }else{ + offset=ret; + } + } + } + + /* In a fully compliant, non-multiplexed stream, we'll still be + holding the last page. In multiplexed (or noncompliant streams), + we will probably have to re-read the last page we saw */ + if(og->header_len==0){ + ret=_seek_helper(vf,offset); + if(ret)return(ret); + + ret=_get_next_page(vf,og,CHUNKSIZE); + if(ret<0) + /* this shouldn't be possible */ + return(OV_EFAULT); + } + + return(offset); +} + +static void _add_serialno(ogg_page *og,ogg_uint32_t **serialno_list, int *n){ + long s = ogg_page_serialno(og); + (*n)++; + + if(*serialno_list){ + *serialno_list = _ogg_realloc(*serialno_list, sizeof(**serialno_list)*(*n)); + }else{ + *serialno_list = _ogg_malloc(sizeof(**serialno_list)); + } + + (*serialno_list)[(*n)-1] = s; +} + +/* returns nonzero if found */ +static int _lookup_serialno(ogg_uint32_t s, ogg_uint32_t *serialno_list, int n){ + if(serialno_list){ + while(n--){ + if(*serialno_list == (ogg_uint32_t) s) return 1; + serialno_list++; + } + } + return 0; +} + +static int _lookup_page_serialno(ogg_page *og, ogg_uint32_t *serialno_list, int n){ + ogg_uint32_t s = ogg_page_serialno(og); + return _lookup_serialno(s,serialno_list,n); +} + +/* performs the same search as _get_prev_page, but prefers pages of + the specified serial number. If a page of the specified serialno is + spotted during the seek-back-and-read-forward, it will return the + info of last page of the matching serial number instead of the very + last page. If no page of the specified serialno is seen, it will + return the info of last page and alter *serialno. */ +static ogg_int64_t _get_prev_page_serial(OggVorbis_File *vf, + ogg_uint32_t *serial_list, int serial_n, + int *serialno, ogg_int64_t *granpos){ + ogg_page og; + ogg_int64_t begin=vf->offset; + ogg_int64_t end=begin; + ogg_int64_t ret; + + ogg_int64_t prefoffset=-1; + ogg_int64_t offset=-1; + ogg_int64_t ret_serialno=-1; + ogg_int64_t ret_gran=-1; + + while(offset==-1){ + begin-=CHUNKSIZE; + if(begin<0) + begin=0; + + ret=_seek_helper(vf,begin); + if(ret)return(ret); + + while(vf->offsetoffset); + if(ret==OV_EREAD)return(OV_EREAD); + if(ret<0){ + break; + }else{ + ret_serialno=ogg_page_serialno(&og); + ret_gran=ogg_page_granulepos(&og); + offset=ret; + + if((ogg_uint32_t)ret_serialno == (ogg_uint32_t)*serialno){ + prefoffset=ret; + *granpos=ret_gran; + } + + if(!_lookup_serialno((ogg_uint32_t)ret_serialno,serial_list,serial_n)){ + /* we fell off the end of the link, which means we seeked + back too far and shouldn't have been looking in that link + to begin with. If we found the preferred serial number, + forget that we saw it. */ + prefoffset=-1; + } + } + } + } + + /* we're not interested in the page... just the serialno and granpos. */ + if(prefoffset>=0)return(prefoffset); + + *serialno = ret_serialno; + *granpos = ret_gran; + return(offset); + +} + +/* uses the local ogg_stream storage in vf; this is important for + non-streaming input sources */ +static int _fetch_headers(OggVorbis_File *vf,vorbis_info *vi, + ogg_uint32_t **serialno_list, int *serialno_n, + ogg_page *og_ptr){ + ogg_page og; + ogg_packet op; + int i,ret; + int allbos=0; + + 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; + } + + vorbis_info_init(vi); +/* vorbis_comment_init(vc); */ + vf->ready_state=OPENED; + + /* extract the serialnos of all BOS pages + the first set of vorbis + headers we see in the link */ + + while(ogg_page_bos(og_ptr)){ + if(serialno_list){ + if(_lookup_page_serialno(og_ptr,*serialno_list,*serialno_n)){ + /* a dupe serialnumber in an initial header packet set == invalid stream */ + if(*serialno_list)_ogg_free(*serialno_list); + *serialno_list=0; + *serialno_n=0; + ret=OV_EBADHEADER; + goto bail_header; + } + + _add_serialno(og_ptr,serialno_list,serialno_n); + } + + if(vf->ready_stateos,ogg_page_serialno(og_ptr)); + ogg_stream_pagein(&vf->os,og_ptr,true); + + if(ogg_stream_packetout(&vf->os,&op) > 0 && + vorbis_synthesis_idheader(&op)){ + /* vorbis header; continue setup */ + vf->ready_state=STREAMSET; + if((ret=vorbis_synthesis_headerin(vi,&op))){ + ret=OV_EBADHEADER; + goto bail_header; + } + } + } + + /* get next page */ + { + ogg_int64_t llret=_get_next_page(vf,og_ptr,CHUNKSIZE); + if(llret==OV_EREAD){ + ret=OV_EREAD; + goto bail_header; + } + if(llret<0){ + ret=OV_ENOTVORBIS; + goto bail_header; + } + + /* if this page also belongs to our vorbis stream, submit it and break */ + if(vf->ready_state==STREAMSET && + vf->os.serialno == ogg_page_serialno(og_ptr)){ + ogg_stream_pagein(&vf->os,og_ptr,true); + break; + } + } + } + + if(vf->ready_state!=STREAMSET){ + ret = OV_ENOTVORBIS; + goto bail_header; + } + + while(1){ + + i=0; + /* discard comment packet */ + if(ogg_stream_discard_packet(vf,og_ptr,CHUNKSIZE) < 0){ + ret=OV_EBADHEADER; + goto bail_header; + } + i++; + + while(i<2){ /* get a page loop */ + + while(i<2){ /* get a packet loop */ + int result=ogg_stream_packetout(&vf->os,&op); + if(result==0)break; + if(result==-1){ + ret=OV_EBADHEADER; + goto bail_header; + } + + if((ret=vorbis_synthesis_headerin(vi,&op))) + goto bail_header; + + i++; + } + + while(i<2){ + if(_get_next_page(vf,og_ptr,CHUNKSIZE)<0){ + ret=OV_EBADHEADER; + goto bail_header; + } + + /* if this page belongs to the correct stream, go parse it */ + if(vf->os.serialno == ogg_page_serialno(og_ptr)){ + ogg_stream_pagein(&vf->os,og_ptr,true); + break; + } + + /* if we never see the final vorbis headers before the link + ends, abort */ + if(ogg_page_bos(og_ptr)){ + if(allbos){ + ret = OV_EBADHEADER; + goto bail_header; + }else + allbos=1; + } + + /* otherwise, keep looking */ + } + } + + return 0; + } + + bail_header: + vorbis_info_clear(vi); +/* vorbis_comment_clear(vc); */ + vf->ready_state=OPENED; + + return ret; +} + +/* Starting from current cursor position, get initial PCM offset of + next page. Consumes the page in the process without decoding + audio, however this is only called during stream parsing upon + seekable open. */ +static ogg_int64_t _initial_pcmoffset(OggVorbis_File *vf, vorbis_info *vi){ + ogg_page og; + ogg_int64_t accumulated=0; + long lastblock=-1; + int result; + ogg_uint32_t serialno = vf->os.serialno; + + while(1){ + ogg_packet op; + if(_get_next_page(vf,&og,-1)<0) + break; /* should not be possible unless the file is truncated/mangled */ + + if(ogg_page_bos(&og)) break; + if(ogg_page_serialno(&og)!= serialno) continue; + + /* count blocksizes of all frames in the page */ + ogg_stream_pagein(&vf->os,&og,true); + while((result=ogg_stream_packetout(&vf->os,&op))){ + if(result>0){ /* ignore holes */ + long thisblock=vorbis_packet_blocksize(vi,&op); + if(lastblock!=-1) + accumulated+=(lastblock+thisblock)>>2; + lastblock=thisblock; + } + } + + if(ogg_page_granulepos(&og)!=-1){ + /* pcm offset of last packet on the first audio page */ + accumulated= ogg_page_granulepos(&og)-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; + + return accumulated; +} + +/* 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_int64_t endgran, + int endserial, + ogg_uint32_t *currentno_list, + int currentnos, + long m){ + ogg_int64_t pcmoffset; + ogg_int64_t dataoffset=searched; + ogg_int64_t endsearched=end; + ogg_int64_t next=end; + ogg_int64_t searchgran=-1; + ogg_page og; + ogg_int64_t ret,last; + int serialno = vf->os.serialno; + + /* invariants: + we have the headers and serialnos for the link beginning at 'begin' + we have the offset and granpos of the last page in the file (potentially + not a page we care about) + */ + + /* Is the last page in our list of current serialnumbers? */ + if(_lookup_serialno(endserial,currentno_list,currentnos)){ + + /* last page is in the starting serialno list, so we've bisected + down to (or just started with) a single link. Now we need to + find the last vorbis page belonging to the first vorbis stream + for this link. */ + + while(endserial != serialno){ + endserial = serialno; + vf->offset=_get_prev_page_serial(vf,currentno_list,currentnos,&endserial,&endgran); + } + + vf->links=m+1; + if(vf->offsets)_ogg_free(vf->offsets); + if(vf->serialnos)_ogg_free(vf->serialnos); + if(vf->dataoffsets)_ogg_free(vf->dataoffsets); + + vf->offsets=_ogg_malloc((vf->links+1)*sizeof(*vf->offsets)); + vf->vi=_ogg_realloc(vf->vi,vf->links*sizeof(*vf->vi)); +/* vf->vc=_ogg_realloc(vf->vc,vf->links*sizeof(*vf->vc));*/ + vf->serialnos=_ogg_malloc(vf->links*sizeof(*vf->serialnos)); + vf->dataoffsets=_ogg_malloc(vf->links*sizeof(*vf->dataoffsets)); + vf->pcmlengths=_ogg_malloc(vf->links*2*sizeof(*vf->pcmlengths)); + + vf->offsets[m+1]=end; + vf->offsets[m]=begin; + vf->pcmlengths[m*2+1]=endgran; + + }else{ + + ogg_uint32_t *next_serialno_list=NULL; + int next_serialnos=0; + vorbis_info vi; +/* vorbis_comment vc; */ + + /* the below guards against garbage seperating the last and + first pages of two links. */ + while(searchedoffset){ + ret=_seek_helper(vf,bisect); + if(ret)return(ret); + } + + last=_get_next_page(vf,&og,-1); + if(last==OV_EREAD)return(OV_EREAD); + if(last<0 || !_lookup_page_serialno(&og,currentno_list,currentnos)){ + endsearched=bisect; + if(last>=0)next=last; + }else{ + searched=vf->offset; + } + } + + /* Bisection point found */ + + /* for the time being, fetch end PCM offset the simple way */ + { + int testserial = serialno+1; + vf->offset = next; + while(testserial != serialno){ + testserial = serialno; + vf->offset=_get_prev_page_serial(vf,currentno_list,currentnos,&testserial,&searchgran); + } + } + + if(vf->offset!=next){ + ret=_seek_helper(vf,next); + if(ret)return(ret); + } + + ret=_fetch_headers(vf,&vi,&next_serialno_list,&next_serialnos,NULL); + if(ret)return(ret); + serialno = vf->os.serialno; + dataoffset = vf->offset; + + /* this will consume a page, however the next bistection always + starts with a raw seek */ + pcmoffset = _initial_pcmoffset(vf,&vi); + + ret=_bisect_forward_serialno(vf,next,vf->offset,end,endgran,endserial, + next_serialno_list,next_serialnos,m+1); + if(ret)return(ret); + + if(next_serialno_list)_ogg_free(next_serialno_list); + + vf->offsets[m+1]=next; + vf->serialnos[m+1]=serialno; + vf->dataoffsets[m+1]=dataoffset; + + vf->vi[m+1]=vi; +/* vf->vc[m+1]=vc; */ + + vf->pcmlengths[m*2+1]=searchgran; + vf->pcmlengths[m*2+2]=pcmoffset; + vf->pcmlengths[m*2+3]-=pcmoffset; + + } + return(0); +} + +static int _make_decode_ready(OggVorbis_File *vf){ + if(vf->ready_state>STREAMSET)return 0; + if(vf->ready_stateseekable){ + if(vorbis_synthesis_init(&vf->vd,vf->vi+vf->current_link)) + return OV_EBADLINK; + }else{ + if(vorbis_synthesis_init(&vf->vd,vf->vi)) + return OV_EBADLINK; + } + vorbis_block_init(&vf->vd,&vf->vb); + vf->ready_state=INITSET; + vf->bittrack=0; + vf->samptrack=0; + return 0; +} + +static int _open_seekable2(OggVorbis_File *vf){ + ogg_int64_t dataoffset=vf->dataoffsets[0],end,endgran=-1; + int endserial=vf->os.serialno; + int serialno=vf->os.serialno; + + /* we're partially open and have a first link header state in + storage in vf */ + + /* fetch initial PCM offset */ + ogg_int64_t pcmoffset = _initial_pcmoffset(vf,vf->vi); + + /* we can seek, so set out learning all about this file */ + if(vf->callbacks.seek_func && vf->callbacks.tell_func){ + (vf->callbacks.seek_func)(vf->datasource,0,SEEK_END); + vf->offset=vf->end=(vf->callbacks.tell_func)(vf->datasource); + }else{ + vf->offset=vf->end=-1; + } + + /* If seek_func is implemented, tell_func must also be implemented */ + if(vf->end==-1) return(OV_EINVAL); + + /* Get the offset of the last page of the physical bitstream, or, if + we're lucky the last vorbis page of this link as most OggVorbis + files will contain a single logical bitstream */ + end=_get_prev_page_serial(vf,vf->serialnos+2,vf->serialnos[1],&endserial,&endgran); + if(end<0)return(end); + + /* now determine bitstream structure recursively */ + if(_bisect_forward_serialno(vf,0,dataoffset,vf->offset,endgran,endserial, + vf->serialnos+2,vf->serialnos[1],0)<0)return(OV_EREAD); + + vf->offsets[0]=0; + vf->serialnos[0]=serialno; + vf->dataoffsets[0]=dataoffset; + vf->pcmlengths[0]=pcmoffset; + vf->pcmlengths[1]-=pcmoffset; + + return(ov_raw_seek(vf,dataoffset)); +} + +/* clear out the current logical bitstream decoder */ +static void _decode_clear(OggVorbis_File *vf){ + vorbis_dsp_clear(&vf->vd); + vorbis_block_clear(&vf->vb); + vf->ready_state=OPENED; +} + +/* 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, + ogg_packet *op_in, + int readp, + int spanp){ + ogg_page og; + + /* handle one packet. Try to fetch it from current stream state */ + /* extract packets from page */ + while(1){ + + if(vf->ready_state==STREAMSET){ + int ret=_make_decode_ready(vf); + if(ret<0)return ret; + } + + /* process a packet if we can. If the machine isn't loaded, + neither is a page */ + if(vf->ready_state==INITSET){ + while(1) { + ogg_packet op; + ogg_packet *op_ptr=(op_in?op_in:&op); + int result=ogg_stream_packetout(&vf->os,op_ptr); + ogg_int64_t granulepos; + + op_in=NULL; + if(result==-1)return(OV_HOLE); /* hole in the data. */ + if(result>0){ + /* got a packet. process it */ + granulepos=op_ptr->granulepos; + if(!vorbis_synthesis(&vf->vb,op_ptr)){ /* lazy check for lazy + header handling. The + header packets aren't + audio, so if/when we + submit them, + vorbis_synthesis will + reject them */ + + /* suck in the synthesis data and track bitrate */ + { + int oldsamples=vorbis_synthesis_pcmout(&vf->vd,NULL); + /* for proper use of libvorbis within libvorbisfile, + oldsamples will always be zero. */ + if(oldsamples)return(OV_EFAULT); + + vorbis_synthesis_blockin(&vf->vd,&vf->vb); + vf->samptrack+=vorbis_synthesis_pcmout(&vf->vd,NULL)-oldsamples; + vf->bittrack+=op_ptr->bytes*8; + } + + /* update the pcm offset. */ + if(granulepos!=-1 && !op_ptr->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_ptr->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_synthesis_pcmout(&vf->vd,NULL); + + granulepos-=samples; + for(i=0;ipcmlengths[i*2+1]; + vf->pcm_offset=granulepos; + } + return(1); + } + } + else + break; + } + } + + if(vf->ready_state>=OPENED){ + ogg_int64_t ret; + + while(1){ + /* the loop is not strictly necessary, but there's no sense in + doing the extra checks of the larger loop for the common + case in a multiplexed bistream where the page is simply + part of a different logical bitstream; keep reading until + we get one with the correct serialno */ + + if(!readp)return(0); + if((ret=_get_next_page(vf,&og,-1))<0){ + return(OV_EOF); /* eof. leave unitialized */ + } + + /* bitrate tracking; add the header's bytes here, the body bytes + are done by packet above */ + vf->bittrack+=og.header_len*8; + + if(vf->ready_state==INITSET){ + if(vf->current_serialno!=ogg_page_serialno(&og)){ + + /* two possibilities: + 1) our decoding just traversed a bitstream boundary + 2) another stream is multiplexed into this logical section */ + + if(ogg_page_bos(&og)){ + /* boundary case */ + if(!spanp) + return(OV_EOF); + + _decode_clear(vf); + + if(!vf->seekable){ + vorbis_info_clear(vf->vi); +/* vorbis_comment_clear(vf->vc); */ + } + break; + + }else + continue; /* possibility #2 */ + } + } + + break; + } + } + + /* 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; + + if(vf->ready_stateseekable){ + ogg_uint32_t 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;linklinks;link++) + if(vf->serialnos[link]==serialno)break; + + if(link==vf->links) continue; /* not the desired Vorbis + bitstream section; keep + trying */ + + vf->current_serialno=serialno; + vf->current_link=link; + + ogg_stream_reset_serialno(&vf->os,vf->current_serialno); + vf->ready_state=STREAMSET; + + }else{ + /* we're streaming */ + /* fetch the three header packets, build the info struct */ + + int ret=_fetch_headers(vf,vf->vi,NULL,NULL,&og); + if(ret)return(ret); + vf->current_serialno=vf->os.serialno; + vf->current_link++; + link=0; + } + } + } + + /* the buffered page is the data we want, and we're ready for it; + add it to the stream state */ + ogg_stream_pagein(&vf->os,&og,true); + + } +} + +static int _ov_open1(void *f,OggVorbis_File *vf,const char *initial, + long ibytes, ov_callbacks callbacks){ + int offsettest=((f && callbacks.seek_func)?callbacks.seek_func(f,0,SEEK_CUR):-1); + ogg_uint32_t *serialno_list=NULL; + int serialno_list_size=0; + int ret; + + memset(vf,0,sizeof(*vf)); + vf->datasource=f; + vf->callbacks = callbacks; + + /* init the framing state */ + ogg_sync_init(&vf->oy); + + /* perhaps some data was previously read into a buffer for testing + against other stream types. Allow initialization from this + previously read data (especially as we may be reading from a + non-seekable stream) */ + if(initial){ + char *buffer=ogg_sync_buffer(&vf->oy,ibytes); + memcpy(buffer,initial,ibytes); + ogg_sync_wrote(&vf->oy,ibytes); + } + + /* can we seek? Stevens suggests the seek test was portable */ + if(offsettest!=-1)vf->seekable=1; + + /* No seeking yet; Set up a 'single' (current) logical bitstream + entry for partial open */ + vf->links=1; + vf->vi=_ogg_calloc(vf->links,sizeof(*vf->vi)); +/* vf->vc=_ogg_calloc(vf->links,sizeof(*vf->vc)); */ + ogg_stream_init(&vf->os,-1); /* fill in the serialno later */ + + /* Fetch all BOS pages, store the vorbis header and all seen serial + numbers, load subsequent vorbis setup headers */ + if((ret=_fetch_headers(vf,vf->vi,&serialno_list,&serialno_list_size,NULL))<0){ + vf->datasource=NULL; + ov_clear(vf); + }else{ + /* serial number list for first link needs to be held somewhere + for second stage of seekable stream open; this saves having to + seek/reread first link's serialnumber data then. */ + vf->serialnos=_ogg_calloc(serialno_list_size+2,sizeof(*vf->serialnos)); + vf->serialnos[0]=vf->current_serialno=vf->os.serialno; + vf->serialnos[1]=serialno_list_size; + memcpy(vf->serialnos+2,serialno_list,serialno_list_size*sizeof(*vf->serialnos)); + + vf->offsets=_ogg_calloc(1,sizeof(*vf->offsets)); + vf->dataoffsets=_ogg_calloc(1,sizeof(*vf->dataoffsets)); + vf->offsets[0]=0; + vf->dataoffsets[0]=vf->offset; + + vf->ready_state=PARTOPEN; + } + if(serialno_list)_ogg_free(serialno_list); + return(ret); +} + +static int _ov_open2(OggVorbis_File *vf){ + if(vf->ready_state != PARTOPEN) return OV_EINVAL; + vf->ready_state=OPENED; + if(vf->seekable){ + int ret=_open_seekable2(vf); + if(ret){ + vf->datasource=NULL; + ov_clear(vf); + } + return(ret); + }else + vf->ready_state=STREAMSET; + + return 0; +} + + +/* clear out the OggVorbis_File struct */ +int ov_clear(OggVorbis_File *vf){ + if(vf){ + vorbis_block_clear(&vf->vb); + vorbis_dsp_clear(&vf->vd); + ogg_stream_clear(&vf->os); + + if(vf->vi && vf->links){ + int i; + for(i=0;ilinks;i++){ + vorbis_info_clear(vf->vi+i); +/* vorbis_comment_clear(vf->vc+i); */ + } + _ogg_free(vf->vi); +/* _ogg_free(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_clear(&vf->oy); + if(vf->datasource && vf->callbacks.close_func) + (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, + const char *initial,long ibytes,ov_callbacks callbacks){ + #if defined(CPU_COLDFIRE) + /* this seems to be the closest we get to an init function, let's init emac + here. rounding is disabled because of MULT31_SHIFT15, which will be + inaccurate with rounding in its current incarnation */ + coldfire_set_macsr(EMAC_FRACTIONAL | EMAC_SATURATE); + #endif + int ret=_ov_open1(f,vf,initial,ibytes,callbacks); + if(ret)return ret; + return _ov_open2(vf); +} + +/* 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_stateseekable || i>=vf->links)return(OV_EINVAL); + if(i<0){ + ogg_int64_t acc=0; + int i; + for(i=0;ilinks;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_stateseekable || i>=vf->links)return(OV_EINVAL); + if(i<0){ + ogg_int64_t acc=0; + int i; + for(i=0;ilinks;i++) + acc+=ov_time_total(vf,i); + return(acc); + }else{ + return(((ogg_int64_t)vf->pcmlengths[i*2+1])*1000/vf->vi[i].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; + int ret; + + if(vf->ready_stateseekable) + return(OV_ENOSEEK); /* don't dump machine if we can't seek */ + + if(pos<0 || pos>vf->end)return(OV_EINVAL); + + /* is the seek position outside our current link [if any]? */ + if(vf->ready_state>=STREAMSET){ + if(posoffsets[vf->current_link] || pos>=vf->offsets[vf->current_link+1]) + _decode_clear(vf); /* clear out stream state */ + } + + /* 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_synthesis_restart(&vf->vd); + + ret=_seek_helper(vf,pos); + if(ret)goto seek_error; + + /* 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. + */ + + { + ogg_page og; + ogg_packet op; + int lastblock=0; + int accblock=0; + int thisblock=0; + int lastflag=0; + int firstflag=0; + ogg_int64_t pagepos=-1; + + ogg_stream_init(&work_os,vf->current_serialno); /* get the memory ready */ + ogg_stream_reset(&work_os); /* eliminate the spurious OV_HOLE + return from not necessarily + starting from the beginning */ + + 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[vf->current_link].codec_setup){ + thisblock=vorbis_packet_blocksize(vf->vi+vf->current_link,&op); + if(thisblock<0){ + ogg_stream_packetout(&vf->os,NULL); + thisblock=0; + }else{ + + /* We can't get a guaranteed correct pcm position out of the + last page in a stream because it might have a 'short' + granpos, which can only be detected in the presence of a + preceding page. However, if the last page is also the first + page, the granpos rules of a first page take precedence. Not + only that, but for first==last, the EOS page must be treated + as if its a normal first page for the stream to open/play. */ + if(lastflag && !firstflag) + 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;ipcmlengths[i*2+1]; + vf->pcm_offset=granulepos-accblock; + if(vf->pcm_offset<0)vf->pcm_offset=0; + break; + } + lastblock=thisblock; + continue; + }else + ogg_stream_packetout(&vf->os,NULL); + } + } + + if(!lastblock){ + pagepos=_get_next_page(vf,&og,-1); + if(pagepos<0){ + vf->pcm_offset=ov_pcm_total(vf,-1); + break; + } + }else{ + /* huh? Bogus stream with packets but no granulepos */ + vf->pcm_offset=-1; + break; + } + + /* has our decoding just traversed a bitstream boundary? */ + if(vf->ready_state>=STREAMSET){ + if(vf->current_serialno!=ogg_page_serialno(&og)){ + + /* two possibilities: + 1) our decoding just traversed a bitstream boundary + 2) another stream is multiplexed into this logical section? */ + + if(ogg_page_bos(&og)){ + /* we traversed */ + _decode_clear(vf); /* clear out stream state */ + ogg_stream_clear(&work_os); + } /* else, do nothing; next loop will scoop another page */ + } + } + + if(vf->ready_statelinks;link++) + if(vf->serialnos[link]==serialno)break; + + if(link==vf->links) continue; /* not the desired Vorbis + bitstream section; keep + trying */ + vf->current_link=link; + vf->current_serialno=serialno; + ogg_stream_reset_serialno(&vf->os,serialno); + ogg_stream_reset_serialno(&work_os,serialno); + vf->ready_state=STREAMSET; + firstflag=(pagepos<=vf->dataoffsets[link]); + } + + ogg_stream_pagein(&vf->os,&og,true); + ogg_stream_pagein(&work_os,&og,true); + lastflag=ogg_page_eos(&og); + + } + } + + ogg_stream_clear(&work_os); + vf->bittrack=0; + vf->samptrack=0; + return(0); + + seek_error: + /* dump the machine so we're in a known state */ + vf->pcm_offset=-1; + ogg_stream_clear(&work_os); + _decode_clear(vf); + return OV_EBADLINK; +} + +/* rescales the number x from the range of [0,from] to [0,to] + x is in the range [0,from] + from, to are in the range [1, 1<<62-1] */ +ogg_int64_t rescale64(ogg_int64_t x, ogg_int64_t from, ogg_int64_t to){ + ogg_int64_t frac=0; + ogg_int64_t ret=0; + int i; + if(x >= from) return to; + if(x <= 0) return 0; + + for(i=0;i<64;i++){ + if(x>=from){ + frac|=1; + x-=from; + } + x<<=1; + frac<<=1; + } + + for(i=0;i<64;i++){ + if(frac & 1){ + ret+=to; + } + frac>>=1; + ret>>=1; + } + + return ret; +} + +/* 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 preceding 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); + + if(vf->ready_stateseekable)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; + } + + /* search within the logical bitstream for the page with the highest + pcm_pos preceding (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; + + ogg_page og; + while(beginoffset){ + result=_seek_helper(vf,bisect); + if(result) goto seek_error; + } + + while(beginoffset); + 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; + result=_seek_helper(vf,bisect); + if(result) goto seek_error; + } + }else{ + ogg_int64_t granulepos; + + if(ogg_page_serialno(&og)!=vf->serialnos[link]) + continue; + + granulepos=ogg_page_granulepos(&og); + if(granulepos==-1)continue; + + if(granuleposoffset; /* 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; + result=_seek_helper(vf,bisect); + if(result) goto seek_error; + }else{ + end=bisect; + endtime=granulepos; + break; + } + } + } + } + } + } + + /* found our page. seek to it, update pcm offset. Easier case than + raw_seek, don't keep packets preceding granulepos. */ + { + ogg_page og; + ogg_packet op; + + /* seek */ + result=_seek_helper(vf,best); + vf->pcm_offset=-1; + if(result) goto seek_error; + result=_get_next_page(vf,&og,-1); + if(result<0) goto seek_error; + + if(link!=vf->current_link){ + /* Different link; dump entire decode machine */ + _decode_clear(vf); + + vf->current_link=link; + vf->current_serialno=vf->serialnos[link]; + vf->ready_state=STREAMSET; + + }else{ + vorbis_synthesis_restart(&vf->vd); + } + + ogg_stream_reset_serialno(&vf->os,vf->current_serialno); + ogg_stream_pagein(&vf->os,&og,true); + + /* 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 + preceding 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. */ + + result=_seek_helper(vf,best); + if(result<0) goto seek_error; + + while(1){ + result=_get_prev_page(vf,&og); + if(result<0) goto seek_error; + if(ogg_page_serialno(&og)==vf->current_serialno && + (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; + return(0); + + seek_error: + /* 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){ + int thisblock,lastblock=0; + int ret=ov_pcm_seek_page(vf,pos); + if(ret<0)return(ret); + if((ret=_make_decode_ready(vf)))return ret; + + /* discard leading packets we don't need for the lapping of the + position we want; don't decode them */ + + while(1){ + ogg_packet op; + ogg_page og; + + int ret=ogg_stream_packetpeek(&vf->os,&op); + if(ret>0){ + thisblock=vorbis_packet_blocksize(vf->vi+vf->current_link,&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_synthesis_trackonly(&vf->vb,&op); /* set up a vb with + only tracking, no + pcm_decode */ + vorbis_synthesis_blockin(&vf->vd,&vf->vb); + + /* 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;icurrent_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(ogg_page_bos(&og))_decode_clear(vf); + + if(vf->ready_statelinks;link++) + if(vf->serialnos[link]==(ogg_uint32_t) serialno)break; + if(link==vf->links) continue; + vf->current_link=link; + + vf->ready_state=STREAMSET; + vf->current_serialno=ogg_page_serialno(&og); + ogg_stream_reset_serialno(&vf->os,serialno); + ret=_make_decode_ready(vf); + if(ret)return ret; + lastblock=0; + } + + ogg_stream_pagein(&vf->os,&og,true); + } + } + + 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_offsetpcm_offset; + long samples=vorbis_synthesis_pcmout(&vf->vd,NULL); + + if(samples>target)samples=target; + vorbis_synthesis_read(&vf->vd,samples); + vf->pcm_offset+=samples; + + if(samplespcm_offset=ov_pcm_total(vf,-1); /* eof */ + } + 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=0; + ogg_int64_t time_total=0; + + if(vf->ready_stateseekable)return(OV_ENOSEEK); + if(milliseconds<0)return(OV_EINVAL); + + /* which bitstream section does this time offset occur in? */ + for(link=0;linklinks;link++){ + ogg_int64_t addsec = ov_time_total(vf,link); + if(millisecondspcmlengths[link*2+1]; + } + + if(link==vf->links)return(OV_EINVAL); + + /* enough information to convert time offset to pcm offset */ + { + ogg_int64_t target=pcm_total+(milliseconds-time_total)*vf->vi[link].rate/1000; + return(ov_pcm_seek(vf,target)); + } +} + +/* 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_stateoffset); +} + +/* 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_stateseekable){ + 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[link].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<0) + if(vf->ready_state>=STREAMSET) + return vf->vi+vf->current_link; + else + return vf->vi; + else + if(link>=vf->links) + return NULL; + else + return vf->vi+link; + }else{ + return vf->vi; + } +} + +/* input values: pcm_channels) a float vector per channel of output + length) the sample length being read by the app + + return values: <0) error/hole in data (OV_HOLE), partial open (OV_EINVAL) + 0) EOF + n) number of samples 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_fixed(OggVorbis_File *vf,ogg_int32_t ***pcm_channels,int length, + int *bitstream){ + if(vf->ready_stateready_state==INITSET){ + ogg_int32_t **pcm; + long samples=vorbis_synthesis_pcmout(&vf->vd,&pcm); + if(samples){ + if(pcm_channels)*pcm_channels=pcm; + if(samples>length)samples=length; + vorbis_synthesis_read(&vf->vd,samples); + vf->pcm_offset+=samples; + if(bitstream)*bitstream=vf->current_link; + return samples; + + } + } + + /* suck in another packet */ + { + int ret=_fetch_and_process_packet(vf,NULL,1,1); + if(ret==OV_EOF) + return(0); + if(ret<=0) + return(ret); + } + } +} + -- cgit v1.2.3