int open_seekable() { VorbisFileInstance instance = makeInstance(); Info initial_i=new Info(); Comment initial_c=new Comment(); int serialno; long end; int ret; int dataoffset; Page og=new Page(); // is this even vorbis...? int[] foo=new int[1]; ret = fetch_headers(initial_i, initial_c, foo, null, instance); serialno=foo[0]; dataoffset=(int)offset; //!! instance.os.clear(); if(ret==-1)return(-1); // we can seek, so set out learning all about this file skable=true; //(callbacks.seek_func)(datasource, 0, SEEK_END); fseek(datasource, 0, SEEK_END); //offset=end=(callbacks.tell_func)(datasource); offset=ftell(datasource); end=offset; // 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(og, instance); // moer than one logical bitstream? if(og.serialno()!=serialno) { // Chained bitstream. Bisect-search each logical bitstream // section. Do so based on serial number only if(bisect_forward_serialno(0,0,end+1,serialno,0, instance)<0) { clear(); return OV_EREAD; } } else { // Only one logical bitstream if(bisect_forward_serialno(0,end,end+1,serialno,0, instance)<0) { clear(); return OV_EREAD; } } prefetch_all_headers(initial_i, initial_c, dataoffset, instance); //return(raw_seek(0)); return 0; }
/* This will flush remaining packets into a page (returning nonzero), even if there is not enough data to trigger a flush normally (undersized page). If there are no packets or partial packets to flush, ogg_stream_flush returns 0. Note that ogg_stream_flush will try to flush a normal sized page like ogg_stream_pageout; a call to ogg_stream_flush does not gurantee that all packets have flushed. Only a return value of 0 from ogg_stream_flush indicates all packet data is flushed into pages. ogg_stream_page will flush the last page in a stream even if it's undersized; you almost certainly want to use ogg_stream_pageout (and *not* ogg_stream_flush) unless you need to flush an undersized page in the middle of a stream for some reason. */ public int flush(Page og) { //System.out.println(this+" ---body_returned: "+body_returned); int i; int vals=0; int maxvals=(lacing_fill>255?255:lacing_fill); int bytes=0; int acc=0; long granule_pos=granule_vals[0]; if(maxvals==0)return(0); /* construct a page */ /* decide how many segments to include */ /* If this is the initial header case, the first page must only include the initial header packet */ if(b_o_s==0) { /* 'initial header page' case */ granule_pos=0; for(vals=0;vals<maxvals;vals++) { if((lacing_vals[vals]&0x0ff)<255) { vals++; break; } } } else { for(vals=0;vals<maxvals;vals++) { if(acc>4096)break; acc+=(lacing_vals[vals]&0x0ff); granule_pos=granule_vals[vals]; } } /* construct the header in temp storage */ String oggs_str = "OggS"; Encoding AE = Encoding.UTF8; byte[] oggs_byt = AE.GetBytes(oggs_str); Array.Copy(oggs_byt, 0, header, 0, oggs_byt.Length); /* stream structure version */ header[4]=0x00; /* continued packet flag? */ header[5]=0x00; if((lacing_vals[0]&0x100)==0)header[5]|=0x01; /* first page flag? */ if(b_o_s==0) header[5]|=0x02; /* last page flag? */ if(e_o_s!=0 && lacing_fill==vals) header[5]|=0x04; b_o_s=1; /* 64 bits of PCM position */ for(i=6;i<14;i++) { header[i]=(byte)granule_pos; granule_pos>>=8; } /* 32 bits of stream serial number */ { int _serialno=serialno; for(i=14;i<18;i++) { header[i]=(byte)_serialno; _serialno>>=8; } } /* 32 bits of page counter (we have both counter and page header because this val can roll over) */ if(pageno==-1)pageno=0; /* because someone called stream_reset; this would be a strange thing to do in an encode stream, but it has plausible uses */ { int _pageno=pageno++; for(i=18;i<22;i++) { header[i]=(byte)_pageno; _pageno>>=8; } } /* zero for computation; filled in later */ header[22]=0; header[23]=0; header[24]=0; header[25]=0; /* segment table */ header[26]=(byte)vals; for(i=0;i<vals;i++) { header[i+27]=(byte)lacing_vals[i]; bytes+=(header[i+27]&0xff); } /* set pointers in the ogg_page struct */ og.header_base=header; og.header=0; og.header_len=header_fill=vals+27; og.body_base=body_data; og.body=body_returned; og.body_len=bytes; /* advance the lacing data and set the body_returned pointer */ lacing_fill-=vals; Array.Copy(lacing_vals, vals, lacing_vals, 0, lacing_fill*4); Array.Copy(granule_vals, vals, granule_vals, 0, lacing_fill*8); body_returned+=bytes; /* calculate the checksum */ og.checksum(); /* done */ return(1); }
// uses the local ogg_stream storage in vf; this is important for // non-streaming input sources public int fetch_headers(Info vi, Comment vc, int[] serialno, Page og_ptr, VorbisFileInstance instance) { //System.err.println("fetch_headers"); Page og=new Page(); Packet op=new Packet(); int ret; if(og_ptr==null) { ret = get_next_page(og, CHUNKSIZE, instance); if(ret==OV_EREAD)return OV_EREAD; if(ret<0) return OV_ENOTVORBIS; og_ptr=og; } if(serialno!=null)serialno[0]=og_ptr.serialno(); instance.os.init(og_ptr.serialno()); // extract the initial header from the first page and verify that the // Ogg bitstream is in fact Vorbis data vi.init(); vc.init(); int i=0; while(i<3) { instance.os.pagein(og_ptr); while(i<3) { int result = instance.os.packetout(op); if(result==0)break; if(result==-1) { Console.Error.WriteLine("Corrupt header in logical bitstream."); //goto bail_header; vi.clear(); vc.clear(); instance.os.clear(); return -1; } if(vi.synthesis_headerin(vc, op)!=0) { Console.Error.WriteLine("Illegal header in logical bitstream."); //goto bail_header; vi.clear(); vc.clear(); instance.os.clear(); return -1; } i++; } if(i<3) if(get_next_page(og_ptr, 1, instance)<0) { Console.Error.WriteLine("Missing header in logical bitstream."); //goto bail_header; vi.clear(); vc.clear(); instance.os.clear(); return -1; } } return 0; }
// last step of the OggVorbis_File initialization; get all the // vorbis_info structs and PCM positions. Only called by the seekable // initialization (local stream storage is hacked slightly; pay // attention to how that's done) public void prefetch_all_headers(Info first_i,Comment first_c, int dataoffset, VorbisFileInstance instance) { Page og=new Page(); int ret; vi=new Info[links]; vc=new Comment[links]; dataoffsets=new long[links]; pcmlengths=new long[links]; serialnos=new int[links]; for(int i=0;i<links;i++) { if(first_i!=null && first_c!=null && i==0) { // we already grabbed the initial header earlier. This just // saves the waste of grabbing it again // !!!!!!!!!!!!! vi[i]=first_i; //memcpy(vf->vi+i,first_i,sizeof(vorbis_info)); vc[i]=first_c; //memcpy(vf->vc+i,first_c,sizeof(vorbis_comment)); dataoffsets[i]=dataoffset; } else { // seek to the location of the initial header seek_helper(offsets[i], instance); //!!! if (fetch_headers(vi[i], vc[i], null, null, instance) == -1) { Console.Error.WriteLine("Error opening logical bitstream #"+(i+1)+"\n"); dataoffsets[i]=-1; } else { dataoffsets[i]=offset; instance.os.clear(); } } // get the serial number and PCM length of this link. To do this, // get the last page of the stream long end=offsets[i+1]; //!!! seek_helper(end, instance); while(true) { ret=get_prev_page(og, instance); if(ret==-1) { // this should not be possible Console.Error.WriteLine("Could not find last page of logical "+ "bitstream #"+(i)+"\n"); vi[i].clear(); vc[i].clear(); break; } if(og.granulepos()!=-1) { serialnos[i]=og.serialno(); pcmlengths[i]=og.granulepos(); break; } } } }
private int get_prev_page(Page page, VorbisFileInstance instance) { long begin=offset; //!!! int ret; int offst=-1; while(offst==-1) { begin-=CHUNKSIZE; if(begin<0) begin=0; seek_helper(begin, instance); while(offset<begin+CHUNKSIZE) { ret=get_next_page(page, begin+CHUNKSIZE-offset, instance); if(ret==OV_EREAD){ return OV_EREAD; } if(ret<0){ break; } else{ offst=ret; } } } seek_helper(offst, instance); //!!! ret=get_next_page(page, CHUNKSIZE, instance); if(ret<0) { //System.err.println("Missed page fencepost at end of logical bitstream Exiting"); //System.exit(1); return OV_EFAULT; } return offst; }
public int bisect_forward_serialno(long begin, long searched, long end, int currentno, int m, VorbisFileInstance instance) { long endsearched=end; long next=end; Page page=new Page(); int ret; while(searched<endsearched) { long bisect; if(endsearched-searched<CHUNKSIZE) { bisect=searched; } else { bisect=(searched+endsearched)/2; } seek_helper(bisect, instance); ret = get_next_page(page, -1, instance); if(ret==OV_EREAD) return OV_EREAD; if(ret<0 || page.serialno()!=currentno) { endsearched=bisect; if(ret>=0)next=ret; } else { searched=ret+page.header_len+page.body_len; } } seek_helper(next, instance); ret = get_next_page(page, -1, instance); if(ret==OV_EREAD) return OV_EREAD; if(searched>=end || ret==-1) { links=m+1; offsets=new long[m+2]; offsets[m+1]=searched; } else { ret=bisect_forward_serialno(next, offset, end, page.serialno(), m+1, instance); if(ret==OV_EREAD)return OV_EREAD; } offsets[m]=begin; return 0; }
// seek to a sample offset relative to the decompressed pcm stream // returns zero on success, nonzero on failure public int pcm_seek(long pos) { int link=-1; long total=pcm_total(-1); if(!skable)return(-1); // don't dump machine if we can't seek if(pos<0 || pos>total) { //goto seek_error; pcm_offset=-1; decode_clear(); return -1; } // which bitstream section does this pcm offset occur in? for(link=links-1;link>=0;link--) { total-=pcmlengths[link]; if(pos>=total)break; } // 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) { long target=pos-total; long end=offsets[link+1]; long begin=offsets[link]; int best=(int)begin; Page og=new Page(); while(begin<end) { long bisect; int ret; if(end-begin<CHUNKSIZE) { bisect=begin; } else { bisect=(end+begin)/2; } seek_helper(bisect); ret=get_next_page(og,end-bisect); if(ret==-1) { end=bisect; } else { long granulepos=og.granulepos(); if(granulepos<target) { best=ret; // raw offset of packet with granulepos begin=offset; // raw offset of next packet } else { end=bisect; } } } // found our page. seek to it (call raw_seek). if(raw_seek(best)!=0) { //goto seek_error; pcm_offset=-1; decode_clear(); return -1; } } // verify result if(pcm_offset>=pos) { //goto seek_error; pcm_offset=-1; decode_clear(); return -1; } if(pos>pcm_total(-1)) { //goto seek_error; pcm_offset=-1; decode_clear(); return -1; } // discard samples until we reach the desired position. Crossing a // logical bitstream boundary with abandon is OK. while(pcm_offset<pos) { float[][] pcm; int target=(int)(pos-pcm_offset); float[][][] _pcm=new float[1][][]; int[] _index=new int[getInfo(-1).channels]; int samples=vd.synthesis_pcmout(_pcm, _index); pcm=_pcm[0]; if(samples>target)samples=target; vd.synthesis_read(samples); pcm_offset+=samples; if(samples<target) if(process_packet(1)==0) { pcm_offset=pcm_total(-1); // eof } } return 0; // seek_error: // dump machine so we're in a known state //pcm_offset=-1; //decode_clear(); //return -1; }
Stream DecodeStream( Stream input, bool skipWavHeader ) { int convsize = 4096 * 2; byte [] convbuffer = new byte [ convsize ]; Stream output = new MemoryStream (); if ( !skipWavHeader ) output.Seek ( HEADER_SIZE, SeekOrigin.Begin ); SyncState oy = new SyncState (); StreamState os = new StreamState (); Page og = new Page (); Packet op = new Packet (); Info vi = new Info (); Comment vc = new Comment (); DspState vd = new DspState (); Block vb = new Block ( vd ); byte [] buffer; int bytes = 0; oy.init (); while ( true ) { int eos = 0; int index = oy.buffer ( 4096 ); buffer = oy.data; bytes = input.Read ( buffer, index, 4096 ); oy.wrote ( bytes ); if ( oy.pageout ( og ) != 1 ) { if ( bytes < 4096 ) break; throw new Exception ( "Input does not appear to be an Ogg bitstream." ); } os.init ( og.serialno () ); vi.init (); vc.init (); if ( os.pagein ( og ) < 0 ) { throw new Exception ( "Error reading first page of Ogg bitstream data." ); } if ( os.packetout ( op ) != 1 ) { throw new Exception ( "Error reading initial header packet." ); } if ( vi.synthesis_headerin ( vc, op ) < 0 ) { throw new Exception ( "This Ogg bitstream does not contain Vorbis audio data." ); } int i = 0; while ( i < 2 ) { while ( i < 2 ) { int result = oy.pageout ( og ); if ( result == 0 ) break; if ( result == 1 ) { os.pagein ( og ); while ( i < 2 ) { result = os.packetout ( op ); if ( result == 0 ) break; if ( result == -1 ) { throw new Exception ( "Corrupt secondary header. Exiting." ); } vi.synthesis_headerin ( vc, op ); i++; } } } index = oy.buffer ( 4096 ); buffer = oy.data; bytes = input.Read ( buffer, index, 4096 ); if ( bytes == 0 && i < 2 ) { throw new Exception ( "End of file before finding all Vorbis headers!" ); } oy.wrote ( bytes ); } { byte [] [] ptr = vc.user_comments; for ( int j = 0; j < vc.user_comments.Length; j++ ) { if ( ptr [ j ] == null ) break; } } convsize = 4096 / vi.channels; vd.synthesis_init ( vi ); vb.init ( vd ); float [] [] [] _pcm = new float [ 1 ] [][]; int [] _index = new int [ vi.channels ]; while ( eos == 0 ) { while ( eos == 0 ) { int result = oy.pageout ( og ); if ( result == 0 ) break; if ( result == -1 ) throw new Exception ( "Corrupt or missing data in bitstream; continuing..." ); else { os.pagein ( og ); while ( true ) { result = os.packetout ( op ); if ( result == 0 ) break; if ( result == -1 ) { } else { int samples; if ( vb.synthesis ( op ) == 0 ) { vd.synthesis_blockin ( vb ); } while ( ( samples = vd.synthesis_pcmout ( _pcm, _index ) ) > 0 ) { float [] [] pcm = _pcm [ 0 ]; bool clipflag = false; int bout = ( samples < convsize ? samples : convsize ); for ( i = 0; i < vi.channels; i++ ) { int ptr = i * 2; int mono = _index [ i ]; for ( int j = 0; j < bout; j++ ) { int val = ( int ) ( pcm [ i ] [ mono + j ] * 32767.0 ); if ( val > 32767 ) { val = 32767; clipflag = true; } if ( val < -32768 ) { val = -32768; clipflag = true; } if ( val < 0 ) val = val | 0x8000; convbuffer [ ptr ] = ( byte ) ( val ); convbuffer [ ptr + 1 ] = ( byte ) ( ( uint ) val >> 8 ); ptr += 2 * ( vi.channels ); } } if ( clipflag ) { } output.Write ( convbuffer, 0, 2 * vi.channels * bout ); vd.synthesis_read ( bout ); } } } if ( og.eos () != 0 ) eos = 1; } } if ( eos == 0 ) { index = oy.buffer ( 4096 ); buffer = oy.data; bytes = input.Read ( buffer, index, 4096 ); oy.wrote ( bytes ); if ( bytes == 0 ) eos = 1; } } os.clear (); vb.clear (); vd.clear (); vi.clear (); } oy.clear (); output.Seek ( 0, SeekOrigin.Begin ); if ( !skipWavHeader ) { WriteHeader ( output, ( int ) ( output.Length - HEADER_SIZE ), vi.rate, ( ushort ) 16, ( ushort ) vi.channels ); output.Seek ( 0, SeekOrigin.Begin ); } return output; }
/// <summary> /// Decodes a stream of Ogg Vorbis data into wav file format. /// </summary> /// <returns> /// A MemoryStream with the entire decoded stream. /// </returns> /// <param name='input'> /// Ogg Vorbis data to be decoded /// </param> /// <param name='output'> /// <para>Stream to write wav data.</para> /// <para>If writeWavHeader is true then this stream must be seekable.</para> /// </param> /// <param name='writeWavHeader'> /// Write wav header in the beginning of the returned stream. /// </param> public static void DecodeStream(Stream input, Stream output, bool writeWavHeader) { int convsize = 4096 * 2; byte[] convbuffer = new byte[convsize]; // take 8k out of the data segment, not the stack long start = output.Position; DebugWriter s_err = new DebugWriter(); if (writeWavHeader && !output.CanSeek) throw new ArgumentException("To write wav header, the output stream must be seekable.", "output"); if (writeWavHeader) output.Seek(HEADER_SIZE, SeekOrigin.Current); // reserve place for WAV header SyncState oy = new SyncState(); // sync and verify incoming physical bitstream StreamState os = new StreamState(); // take physical pages, weld into a logical stream of packets Page og = new Page(); // one Ogg bitstream page. Vorbis packets are inside Packet op = new Packet(); // one raw packet of data for decode Info vi = new Info(); // struct that stores all the static vorbis bitstream settings Comment vc = new Comment(); // struct that stores all the bitstream user comments DspState vd = new DspState(); // central working state for the packet->PCM decoder Block vb = new Block(vd); // local working space for packet->PCM decode int bytes = 0; // Decode setup oy.init(); // Now we can read pages // we repeat if the bitstream is chained while (true) { int eos = 0; // grab some data at the head of the stream. We want the first page // (which is guaranteed to be small and only contain the Vorbis // stream initial header) We need the first page to get the stream // serialno. // submit a 4k block to libvorbis' Ogg layer int index = oy.buffer(4096); bytes = input.Read(oy.data, index, 4096); oy.wrote(bytes); // Get the first page. if (oy.pageout(og) != 1) { // have we simply run out of data? If so, we're done. if (bytes < 4096) break; // error case. Must not be Vorbis data s_err.WriteLine("Input does not appear to be an Ogg bitstream."); } // Get the serial number and set up the rest of decode. // serialno first; use it to set up a logical stream os.init(og.serialno()); // extract the initial header from the first page and verify that the // Ogg bitstream is in fact Vorbis data // I handle the initial header first instead of just having the code // read all three Vorbis headers at once because reading the initial // header is an easy way to identify a Vorbis bitstream and it's // useful to see that functionality seperated out. vi.init(); vc.init(); if (os.pagein(og) < 0) { // error; stream version mismatch perhaps s_err.WriteLine("Error reading first page of Ogg bitstream data."); } if (os.packetout(op) != 1) { // no page? must not be vorbis s_err.WriteLine("Error reading initial header packet."); } if (vi.synthesis_headerin(vc, op) < 0) { // error case; not a vorbis header s_err.WriteLine("This Ogg bitstream does not contain Vorbis audio data."); } // At this point, we're sure we're Vorbis. We've set up the logical // (Ogg) bitstream decoder. Get the comment and codebook headers and // set up the Vorbis decoder // The next two packets in order are the comment and codebook headers. // They're likely large and may span multiple pages. Thus we reead // and submit data until we get our two pacakets, watching that no // pages are missing. If a page is missing, error out; losing a // header page is the only place where missing data is fatal. */ int i = 0; while (i < 2) { while (i < 2) { int result = oy.pageout(og); if (result == 0) break; // Need more data // Don't complain about missing or corrupt data yet. We'll // catch it at the packet output phase if (result == 1) { os.pagein(og); // we can ignore any errors here // as they'll also become apparent // at packetout while (i < 2) { result = os.packetout(op); if (result == 0) break; if (result == -1) { // Uh oh; data at some point was corrupted or missing! // We can't tolerate that in a header. Die. s_err.WriteLine("Corrupt secondary header. Exiting."); } vi.synthesis_headerin(vc, op); i++; } } } // no harm in not checking before adding more index = oy.buffer(4096); bytes = input.Read(oy.data, index, 4096); if (bytes == 0 && i < 2) { s_err.WriteLine("End of file before finding all Vorbis headers!"); } oy.wrote(bytes); } // Throw the comments plus a few lines about the bitstream we're // decoding { byte[][] ptr = vc.user_comments; for (int j = 0; j < vc.user_comments.Length; j++) { if (ptr [j] == null) break; s_err.WriteLine(vc.getComment(j)); } s_err.WriteLine("\nBitstream is " + vi.channels + " channel, " + vi.rate + "Hz"); s_err.WriteLine("Encoded by: " + vc.getVendor() + "\n"); } convsize = 4096 / vi.channels; // OK, got and parsed all three headers. Initialize the Vorbis // packet->PCM decoder. vd.synthesis_init(vi); // central decode state vb.init(vd); // local state for most of the decode // so multiple block decodes can // proceed in parallel. We could init // multiple vorbis_block structures // for vd here float[][][] _pcm = new float[1][][]; int[] _index = new int[vi.channels]; // The rest is just a straight decode loop until end of stream while (eos == 0) { while (eos == 0) { int result = oy.pageout(og); if (result == 0) break; // need more data if (result == -1) { // missing or corrupt data at this page position s_err.WriteLine("Corrupt or missing data in bitstream; continuing..."); } else { os.pagein(og); // can safely ignore errors at // this point while (true) { result = os.packetout(op); if (result == 0) break; // need more data if (result == -1) { // missing or corrupt data at this page position // no reason to complain; already complained above } else { // we have a packet. Decode it int samples; if (vb.synthesis(op) == 0) { // test for success! vd.synthesis_blockin(vb); } // **pcm is a multichannel float vector. In stereo, for // example, pcm[0] is left, and pcm[1] is right. samples is // the size of each channel. Convert the float values // (-1.<=range<=1.) to whatever PCM format and write it out while ((samples = vd.synthesis_pcmout(_pcm, _index)) > 0) { float[][] pcm = _pcm [0]; bool clipflag = false; int bout = (samples < convsize ? samples : convsize); // convert floats to 16 bit signed ints (host order) and // interleave for (i = 0; i < vi.channels; i++) { int ptr = i * 2; //int ptr=i; int mono = _index [i]; for (int j = 0; j < bout; j++) { int val = (int)(pcm [i] [mono + j] * 32767.0); // short val=(short)(pcm[i][mono+j]*32767.); // int val=(int)Math.round(pcm[i][mono+j]*32767.); // might as well guard against clipping if (val > 32767) { val = 32767; clipflag = true; } if (val < -32768) { val = -32768; clipflag = true; } if (val < 0) val = val | 0x8000; convbuffer [ptr] = (byte)(val); convbuffer [ptr + 1] = (byte)((uint)val >> 8); ptr += 2 * (vi.channels); } } if (clipflag) { //s_err.WriteLine("Clipping in frame "+vd.sequence); } output.Write(convbuffer, 0, 2 * vi.channels * bout); vd.synthesis_read(bout); // tell libvorbis how // many samples we // actually consumed } } } if (og.eos() != 0) eos = 1; } } if (eos == 0) { index = oy.buffer(4096); bytes = input.Read(oy.data, index, 4096); oy.wrote(bytes); if (bytes == 0) eos = 1; } } // clean up this logical bitstream; before exit we see if we're // followed by another [chained] os.clear(); // ogg_page and ogg_packet structs always point to storage in // libvorbis. They're never freed or manipulated directly vb.clear(); vd.clear(); vi.clear(); // must be called last } // OK, clean up the framer oy.clear(); s_err.WriteLine("Done."); if (writeWavHeader) { long end = output.Position; int length = (int)(end - (start + HEADER_SIZE)); output.Seek(start, SeekOrigin.Begin); WriteHeader(output, length, vi.rate, (ushort)16, (ushort)vi.channels); output.Seek(end, SeekOrigin.Begin); } }
// fetch and process a packet. Handles the case where we're at a // bitstream boundary and dumps the decoding machine. If the decoding // machine is unloaded, it loads it. It also keeps pcm_offset up to // date (seek and read both use this. seek uses a special hack with // readp). // // return: -1) hole in the data (lost packet) // 0) need more date (only if readp==0)/eof // 1) got a packet int process_packet(int readp) { Page og=new Page(); // handle one packet. Try to fetch it from current stream state // extract packets from page while(true) { // process a packet if we can. If the machine isn't loaded, // neither is a page if(decode_ready) { Packet op=new Packet(); int result=os.packetout(op); long granulepos; // if(result==-1)return(-1); // hole in the data. For now, swallow // and go. We'll need to add a real // error code in a bit. if(result>0) { // got a packet. process it granulepos=op.granulepos; if(vb.synthesis(op)==0) { // 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=vd.synthesis_pcmout(null, null); vd.synthesis_blockin(vb); samptrack+=vd.synthesis_pcmout(null, null)-oldsamples; bittrack+=op.bytes*8; } // update the pcm offset. if(granulepos!=-1 && op.e_o_s==0) { int link=(skable?current_link:0); int 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 samples=vd.synthesis_pcmout(null, null); granulepos-=samples; for(int i=0;i<link;i++) { granulepos+=pcmlengths[i]; } pcm_offset=granulepos; } return(1); } } } if(readp==0)return(0); if(get_next_page(og,-1)<0)return(0); // eof. leave unitialized // bitrate tracking; add the header's bytes here, the body bytes // are done by packet above bittrack+=og.header_len*8; // has our decoding just traversed a bitstream boundary? if(decode_ready) { if(current_serialno!=og.serialno()) { decode_clear(); } } // 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(!decode_ready) { int i; if(skable) { current_serialno=og.serialno(); // match the serialno to bitstream section. We use this rather than // offset positions to avoid problems near logical bitstream // boundaries for(i=0;i<links;i++) { if(serialnos[i]==current_serialno)break; } if(i==links)return(-1); // sign of a bogus stream. error out, // leave machine uninitialized current_link=i; os.init(current_serialno); os.reset(); } else { // we're streaming // fetch the three header packets, build the info struct int[] foo = new int[1]; int ret=fetch_headers(vi[0], vc[0], foo, og); current_serialno=foo[0]; if(ret!=0)return ret; current_link++; i=0; } make_decode_ready(); } os.pagein(og); } }
public AudioSample OggToWav(Stream ogg, float volume, float pitch) { AudioSample sample = new AudioSample(); TextWriter s_err = new StringWriter(); Stream input = null; MemoryStream output = null; input = ogg; output = new MemoryStream(); SyncState oy = new SyncState(); StreamState os = new StreamState(); Page og = new Page(); Packet op = new Packet(); Info vi = new Info(); Comment vc = new Comment(); DspState vd = new DspState(); Block vb = new Block(vd); byte[] buffer; int bytes = 0; oy.init(); while (true) { int eos = 0; int index = oy.buffer(4096); buffer = oy.data; try { bytes = input.Read(buffer, index, 4096); } catch (Exception e) { s_err.WriteLine(e); } oy.wrote(bytes); if (oy.pageout(og) != 1) { if (bytes < 4096) break; s_err.WriteLine("Input does not appear to be an Ogg bitstream."); } os.init(og.serialno()); vi.init(); vc.init(); if (os.pagein(og) < 0) { s_err.WriteLine("Error reading first page of Ogg bitstream data."); } if (os.packetout(op) != 1) { s_err.WriteLine("Error reading initial header packet."); } if (vi.synthesis_headerin(vc, op) < 0) { s_err.WriteLine("This Ogg bitstream does not contain Vorbis audio data."); } int i = 0; while (i < 2) { while (i < 2) { int result = oy.pageout(og); if (result == 0) break; if (result == 1) { os.pagein(og); while (i < 2) { result = os.packetout(op); if (result == 0) break; vi.synthesis_headerin(vc, op); i++; } } } index = oy.buffer(4096); buffer = oy.data; try { bytes = input.Read(buffer, index, 4096); } catch (Exception e) { s_err.WriteLine(e); } oy.wrote(bytes); } sample.Channels = vi.channels; sample.Rate = (int)((float)vi.rate * pitch); convsize = 4096 / vi.channels; vd.synthesis_init(vi); vb.init(vd); float[][][] _pcm = new float[1][][]; int[] _index = new int[vi.channels]; while (eos == 0) { while (eos == 0) { int result = oy.pageout(og); if (result == 0) break; if (result != -1) { os.pagein(og); while (true) { result = os.packetout(op); if (result == 0) break; if (result != -1) { int samples; if (vb.synthesis(op) == 0) { vd.synthesis_blockin(vb); } while ((samples = vd.synthesis_pcmout(_pcm, _index)) > 0) { float[][] pcm = _pcm[0]; int bout = (samples < convsize ? samples : convsize); for (i = 0; i < vi.channels; i++) { int ptr = i * 2; int mono = _index[i]; for (int j = 0; j < bout; j++) { int val = (int)(pcm[i][mono + j] * 32767.0); if (val > 32767) { val = 32767; } if (val < -32768) { val = -32768; } val = (int)((float)val * volume); if (val < 0) val = val | 0x8000; convbuffer[ptr] = (byte)(val); convbuffer[ptr + 1] = (byte)((uint)val >> 8); ptr += 2 * (vi.channels); } } output.Write(convbuffer, 0, 2 * vi.channels * bout); vd.synthesis_read(bout); } } } if (og.eos() != 0) eos = 1; } } if (eos == 0) { index = oy.buffer(4096); buffer = oy.data; try { bytes = input.Read(buffer, index, 4096); } catch (Exception e) { s_err.WriteLine(e); } oy.wrote(bytes); if (bytes == 0) eos = 1; } } os.clear(); vb.clear(); vd.clear(); vi.clear(); break; } oy.clear(); input.Close(); sample.Pcm = output.ToArray(); return sample; }
public int pageseek(Page og) { int page=returned; int next; int bytes=fill-returned; if(headerbytes==0) { int _headerbytes,i; if(bytes<27)return(0); // not enough for a header /* verify capture pattern */ //!!!!!!!!!!! if(data[page]!='O' || data[page+1]!='g' || data[page+2]!='g' || data[page+3]!='S') { headerbytes=0; bodybytes=0; // search for possible capture next=0; for(int ii=0; ii<bytes-1; ii++) { if(data[page+1+ii]=='O'){next=page+1+ii; break;} } //next=memchr(page+1,'O',bytes-1); if(next==0) next=fill; returned=next; return(-(next-page)); } _headerbytes=(data[page+26]&0xff)+27; if(bytes<_headerbytes)return(0); // not enough for header + seg table // count up body length in the segment table for(i=0;i<(data[page+26]&0xff);i++) { bodybytes+=(data[page+27+i]&0xff); } headerbytes=_headerbytes; } if(bodybytes+headerbytes>bytes)return(0); // The whole test page is buffered. Verify the checksum //lock(chksum) { // Grab the checksum bytes, set the header field to zero Array.Copy(data, page+22, chksum, 0, 4); data[page+22]=0; data[page+23]=0; data[page+24]=0; data[page+25]=0; // set up a temp page struct and recompute the checksum Page log=pageseek_p; log.header_base=data; log.header=page; log.header_len=headerbytes; log.body_base=data; log.body=page+headerbytes; log.body_len=bodybytes; log.checksum(); // Compare if(chksum[0]!=data[page+22] || chksum[1]!=data[page+23] || chksum[2]!=data[page+24] || chksum[3]!=data[page+25]) { // D'oh. Mismatch! Corrupt page (or miscapture and not a page at all) // replace the computed checksum with the one actually read in Array.Copy(chksum, 0, data, page+22, 4); // Bad checksum. Lose sync */ headerbytes=0; bodybytes=0; // search for possible capture next=0; for(int ii=0; ii<bytes-1; ii++) { if(data[page+1+ii]=='O'){next=page+1+ii; break;} } //next=memchr(page+1,'O',bytes-1); if(next==0) next=fill; returned=next; return(-(next-page)); } } // yes, have a whole page all ready to go { page=returned; if(og!=null) { og.header_base=data; og.header=page; og.header_len=headerbytes; og.body_base=data; og.body=page+headerbytes; og.body_len=bodybytes; } unsynced=0; returned+=(bytes=headerbytes+bodybytes); headerbytes=0; bodybytes=0; return(bytes); } // headerbytes=0; // bodybytes=0; // next=0; // for(int ii=0; ii<bytes-1; ii++){ // if(data[page+1+ii]=='O'){next=page+1+ii;} // } // //next=memchr(page+1,'O',bytes-1); // if(next==0) next=fill; // returned=next; // return(-(next-page)); }
// sync the stream and get a page. Keep trying until we find a page. // Supress 'sync errors' after reporting the first. // // return values: // -1) recapture (hole in data) // 0) need more data // 1) page returned // // Returns pointers into buffered data; invalidated by next call to // _stream, _clear, _init, or _buffer public int pageout(Page og) { // all we need to do is verify a page at the head of the stream // buffer. If it doesn't verify, we look for the next potential // frame while(true) { int ret=pageseek(og); if(ret>0) { // have a page return(1); } if(ret==0) { // need more data return(0); } // head did not start a synced page... skipped some bytes if(unsynced==0) { unsynced=1; return(-1); } // loop. keep looking } }
// add the incoming page to the stream state; we decompose the page // into packet segments here as well. public int pagein(Page og) { byte[] header_base=og.header_base; int header=og.header; byte[] body_base=og.body_base; int body=og.body; int bodysize=og.body_len; int segptr=0; int version=og.version(); int continued=og.continued(); int bos=og.bos(); int eos=og.eos(); long granulepos=og.granulepos(); int _serialno=og.serialno(); int _pageno=og.pageno(); int segments=header_base[header+26]&0xff; // clean up 'returned data' { int lr=lacing_returned; int br=body_returned; // body data //System.out.println("br="+br+", body_fill="+body_fill); if(br!=0) { body_fill-=br; if(body_fill!=0) { Array.Copy(body_data, br, body_data, 0, body_fill); } body_returned=0; } //System.out.println("?? br="+br+", body_fill="+body_fill+" body_returned="+body_returned); if(lr!=0) { // segment table if((lacing_fill-lr)!=0) { Array.Copy(lacing_vals, lr, lacing_vals, 0, lacing_fill-lr); Array.Copy(granule_vals, lr, granule_vals, 0, lacing_fill-lr); } lacing_fill-=lr; lacing_packet-=lr; lacing_returned=0; } } // check the serial number if(_serialno!=serialno)return(-1); if(version>0)return(-1); lacing_expand(segments+1); // are we in sequence? if(_pageno!=pageno) { int i; // unroll previous partial packet (if any) for(i=lacing_packet;i<lacing_fill;i++) { body_fill-=lacing_vals[i]&0xff; //System.out.println("??"); } lacing_fill=lacing_packet; // make a note of dropped data in segment table if(pageno!=-1) { lacing_vals[lacing_fill++]=0x400; lacing_packet++; } // are we a 'continued packet' page? If so, we'll need to skip // some segments if(continued!=0) { bos=0; for(;segptr<segments;segptr++) { int val=(header_base[header+27+segptr]&0xff); body+=val; bodysize-=val; if(val<255) { segptr++; break; } } } } //System.out.println("bodysize="+bodysize); if(bodysize!=0) { body_expand(bodysize); Array.Copy(body_base, body, body_data, body_fill, bodysize); body_fill+=bodysize; } //System.out.println("bodyfill="+body_fill); { int saved=-1; while(segptr<segments) { int val=(header_base[header+27+segptr]&0xff); lacing_vals[lacing_fill]=val; granule_vals[lacing_fill]=-1; if(bos!=0) { lacing_vals[lacing_fill]|=0x100; bos=0; } if(val<255)saved=lacing_fill; lacing_fill++; segptr++; if(val<255)lacing_packet=lacing_fill; } /* set the granulepos on the last pcmval of the last full packet */ if(saved!=-1) { granule_vals[saved]=granulepos; } } if(eos!=0) { e_o_s=1; if(lacing_fill>0) lacing_vals[lacing_fill-1]|=0x200; } pageno=_pageno+1; return(0); }
public int get_next_page(Page page, long boundary, VorbisFileInstance instance) { if(boundary>0) boundary+=offset; while(true) { int more; if(boundary>0 && offset>=boundary)return OV_FALSE; more = instance.oy.pageseek(page); if(more<0){offset-=more;} else { if(more==0) { if(boundary==0)return OV_FALSE; // if(get_data()<=0)return -1; int ret=get_data(instance); if(ret==0) return OV_EOF; if(ret<0) return OV_EREAD; } else { int ret=(int)offset; //!!! offset+=more; return ret; } } } }
/* This constructs pages from buffered packet segments. The pointers returned are to static buffers; do not free. The returned buffers are good only until the next call (using the same ogg_stream_state) */ public int pageout(Page og) { if((e_o_s!=0&&lacing_fill!=0) || /* 'were done, now flush' case */ body_fill-body_returned> 4096 || /* 'page nominal size' case */ lacing_fill>=255 || /* 'segment table full' case */ (lacing_fill!=0&&b_o_s==0)) { /* 'initial header page' case */ return flush(og); } return 0; }
public int pageseek(Page og) { int page=returned; int next; int bytes=fill-returned; if(headerbytes==0) { int _headerbytes,i; if(bytes<27)return(0); // not enough for a header /* verify capture pattern */ //!!!!!!!!!!! if(data[page]!='O' || data[page+1]!='g' || data[page+2]!='g' || data[page+3]!='S') { headerbytes=0; bodybytes=0; // search for possible capture next=0; for(int ii=0; ii<bytes-1; ii++) { if(data[page+1+ii]=='O'){next=page+1+ii; break;} } //next=memchr(page+1,'O',bytes-1); if(next==0) next=fill; returned=next; return(-(next-page)); } _headerbytes=(data[page+26]&0xff)+27; if(bytes<_headerbytes)return(0); // not enough for header + seg table // count up body length in the segment table for(i=0;i<(data[page+26]&0xff);i++) { bodybytes+=(data[page+27+i]&0xff); } headerbytes=_headerbytes; } if(bodybytes+headerbytes>bytes)return(0); // The whole test page is buffered. Verify the checksum lock(chksum) { // Grab the checksum bytes, set the header field to zero Array.Copy(data, page+22, chksum, 0, 4); data[page+22]=0; data[page+23]=0; data[page+24]=0; data[page+25]=0; // set up a temp page struct and recompute the checksum Page log=pageseek_p; log.header_base=data; log.header=page; log.header_len=headerbytes; log.body_base=data; log.body=page+headerbytes; log.body_len=bodybytes; log.checksum(); // Compare if(chksum[0]!=data[page+22] || chksum[1]!=data[page+23] || chksum[2]!=data[page+24] || chksum[3]!=data[page+25]) { // D'oh. Mismatch! Corrupt page (or miscapture and not a page at all) // replace the computed checksum with the one actually read in Array.Copy(chksum, 0, data, page+22, 4); // Bad checksum. Lose sync */ headerbytes=0; bodybytes=0; // search for possible capture next=0; for(int ii=0; ii<bytes-1; ii++) { if(data[page+1+ii]=='O'){next=page+1+ii; break;} } //next=memchr(page+1,'O',bytes-1); if(next==0) next=fill; returned=next; return(-(next-page)); } } // yes, have a whole page all ready to go { page=returned; if(og!=null) { og.header_base=data; og.header=page; og.header_len=headerbytes; og.body_base=data; og.body=page+headerbytes; og.body_len=bodybytes; } unsynced=0; returned+=(bytes=headerbytes+bodybytes); headerbytes=0; bodybytes=0; return(bytes); } // headerbytes=0; // bodybytes=0; // next=0; // for(int ii=0; ii<bytes-1; ii++){ // if(data[page+1+ii]=='O'){next=page+1+ii;} // } // //next=memchr(page+1,'O',bytes-1); // if(next==0) next=fill; // returned=next; // return(-(next-page)); }