// clear out the current logical bitstream decoder void decode_clear() { os.clear(); vd.clear(); vb.clear(); decode_ready = false; bittrack = 0.0f; samptrack = 0.0f; }
Stream DecodeStream(Stream input, bool skipWavHeader) { int convsize = 4096 * 2; byte[] convbuffer = new byte[convsize]; // take 8k out of the data segment, not the stack TextWriter s_err = new DebugWriter(); Stream output = new MemoryStream(); if (!skipWavHeader) { output.Seek(HEADER_SIZE, SeekOrigin.Begin); // 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 byte[] buffer; int bytes = 0; // Decode setup oy.init(); // Now we can read pages while (true) { // we repeat if the bitstream is chained 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); buffer = oy.data; try { bytes = input.Read(buffer, index, 4096); } catch (Exception e) { s_err.WriteLine(e); } 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); buffer = oy.data; try { bytes = input.Read(buffer, index, 4096); } catch (Exception e) { s_err.WriteLine(e); } 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); 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; } } } // 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."); 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); }
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); }
// uses the local ogg_stream storage in vf; this is important for // non-streaming input sources int fetch_headers(Info vi, Comment vc, int[] serialno, Page og_ptr) { //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); if(ret==OV_EREAD)return OV_EREAD; if(ret<0) return OV_ENOTVORBIS; og_ptr=og; } if(serialno!=null)serialno[0]=og_ptr.serialno(); 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) { os.pagein(og_ptr); while(i<3) { int result=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(); 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(); os.clear(); return -1; } i++; } if(i<3) if(get_next_page(og_ptr, 1)<0) { Console.Error.WriteLine("Missing header in logical bitstream."); //goto bail_header; vi.clear(); vc.clear(); os.clear(); return -1; } } return 0; }
public IEnumerable <AudioChunk> StreamData(Stream source) { input = source; int convsize = 4096 * 2; byte[] convbuffer = new byte[convsize]; // take 8k out of the data segment, not the stack convsize = 4096 / vi.channels; oy.init(); // Now we can read pages int eos = 0; // so multiple block decodes can // proceed in parallel. We could init // multiple vorbis_block structures for vd here float[][] pcm = null; 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 } 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) { continue; } // missing or corrupt data at this page position // no reason to complain; already complained above // 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(ref pcm, _index)) > 0) { int bout = (samples < convsize ? samples : convsize); // convert floats to 16 bit signed ints (host order) and interleave for (int ch = 0; ch < vi.channels; ch++) { int ptr = ch * 2; int offset = _index[ch]; float[] chPcm = pcm[ch]; for (int j = 0; j < bout; j++) { int val = (int)(chPcm[offset + j] * 32767); if (val > 32767) { val = 32767; } if (val < -32768) { val = -32768; } if (val < 0) { val = val | 0x8000; } convbuffer[ptr] = (byte)(val); convbuffer[ptr + 1] = (byte)((uint)val >> 8); ptr += 2 * (vi.channels); } } chunk.Data = convbuffer; chunk.Length = 2 * vi.channels * bout; vd.synthesis_read(bout); yield return(chunk); } } if (og.eos() != 0) { eos = 1; } } if (eos == 0) { int index = oy.buffer(4096); buffer = oy.data; bytes = input.Read(buffer, 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 vi.clear(); // must be called last // OK, clean up the framer oy.clear(); yield break; }