Exemplo n.º 1
0
        private IEnumerable <ArraySegment <byte> > DecodeTo(Stream OggBaseStream, InfoHolderClass InfoHolder)
        {
            byte[] buffer;
            int    bytes       = 0;
            int    convsize    = 4096 * 2;
            var    convbuffer  = new byte[convsize]; // take 8k out of the data segment, not the stack
            var    SyncState   = new SyncState();    // sync and verify incoming physical bitstream
            var    StreamState = new StreamState();  // take physical pages, weld into a logical stream of packets
            var    Page        = new Page();         // one Ogg bitstream page.  Vorbis packets are inside
            var    Packet      = new Packet();       // one raw packet of data for decode

            var Info     = new Info();               // struct that stores all the static vorbis bitstream settings
            var Comment  = new Comment();            // struct that stores all the bitstream user comments
            var DspState = new DspState();           // central working state for the packet->PCM decoder
            var Block    = new Block(DspState);      // local working space for packet->PCM decode

            // Decode setup

            SyncState.Init();             // Now we can read pages

            // we repeat if the bitstream is chained
            while (true)
            {
                bool eos = false;

                // 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 = SyncState.Buffer(4096);
                buffer = SyncState.Data;
                bytes  = OggBaseStream.Read(buffer, index, 4096);
                SyncState.Wrote(bytes);

                // Get the first page.
                int _result = SyncState.PageOut(Page);
                if (_result != 1)
                {
                    // have we simply run out of data?  If so, we're done.
                    if (bytes < 4096)
                    {
                        break;
                    }

                    Debug.WriteLine(bytes + "; " + _result);
                    //File.WriteAllBytes();
                    // error case.  Must not be Vorbis data
                    //Debug.WriteLine("Input does not appear to be an Ogg bitstream.");
                    throw (new Exception("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
                StreamState.Init(Page.BitStreamSerialNumber);

                // 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.

                Info.Init();
                Comment.init();
                // error; stream version mismatch perhaps
                if (StreamState.PageIn(Page) < 0)
                {
                    throw (new Exception("Error reading first page of Ogg bitstream data."));
                }
                // no page? must not be vorbis
                if (StreamState.PacketOut(Packet) != 1)
                {
                    throw (new Exception("Error reading initial header packet."));
                }
                // error case; not a vorbis header
                if (Info.SynthesisHeaderIn(Comment, Packet) < 0)
                {
                    throw (new Exception("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 = SyncState.PageOut(Page);
                        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)
                        {
                            StreamState.PageIn(Page);                             // we can ignore any errors here
                            // as they'll also become apparent
                            // at packetout
                            while (i < 2)
                            {
                                result = StreamState.PacketOut(Packet);
                                if (result == 0)
                                {
                                    break;
                                }

                                // Uh oh; data at some point was corrupted or missing!
                                // We can't tolerate that in a header.  Die.
                                if (result == -1)
                                {
                                    throw (new Exception("Corrupt secondary header.  Exiting."));
                                }
                                Info.SynthesisHeaderIn(Comment, Packet);
                                i++;
                            }
                        }
                    }
                    // no harm in not checking before adding more
                    index  = SyncState.Buffer(4096);
                    buffer = SyncState.Data;
                    bytes  = OggBaseStream.Read(buffer, index, 4096);
                    if (bytes == 0 && i < 2)
                    {
                        throw (new Exception("End of file before finding all Vorbis headers!"));
                    }
                    SyncState.Wrote(bytes);
                }

                // Throw the comments plus a few lines about the bitstream we're
                // decoding
#if false
                {
                    byte[][] ptr = Comment.user_comments;
                    for (int j = 0; j < ptr.Length; j++)
                    {
                        if (ptr[j] == null)
                        {
                            break;
                        }
                        Debug.WriteLine(Util.InternalEncoding.GetString(ptr[j], 0, ptr[j].Length - 1));
                    }
                    Debug.WriteLine("\nBitstream is {0} channel, {1}Hz", Info.channels, Info.rate);
                    Debug.WriteLine("Encoded by: {0}\n", Util.InternalEncoding.GetString(Comment.vendor, 0, Comment.vendor.Length - 1));
                }
#endif
                convsize = 4096 / Info.Channels;
                //convsize = 4096 / Info.channels * 2;

                InfoHolder.Info = Info;
                yield return(new ArraySegment <byte>());


                // OK, got and parsed all three headers. Initialize the Vorbis
                //  packet->PCM decoder.
                DspState.synthesis_init(Info);        // central decode state
                Block.init(DspState);                 // 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[Info.Channels];
                // The rest is just a straight decode loop until end of stream
                while (!eos)
                {
                    while (!eos)
                    {
                        int result = SyncState.PageOut(Page);
                        if (result == 0)
                        {
                            break;                                      // need more data
                        }
                        if (result == -1)
                        {
                            // missing or corrupt data at this page position
                            Debug.WriteLine("Corrupt or missing data in bitstream; continuing...");
                        }
                        else
                        {
                            StreamState.PageIn(Page);                             // can safely ignore errors at
                            // this point
                            while (true)
                            {
                                result = StreamState.PacketOut(Packet);

                                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 (Block.synthesis(Packet) == 0)
                                    {                                     // test for success!
                                        DspState.synthesis_blockin(Block);
                                    }

                                    // **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 = DspState.synthesis_pcmout(_pcm, _index)) > 0)
                                    {
                                        float[][] pcm  = _pcm[0];
                                        int       bout = (samples < convsize ? samples : convsize);

                                        // convert floats to 16 bit signed ints (host order) and
                                        // interleave
                                        for (i = 0; i < Info.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;
                                                }
                                                if (val < -32768)
                                                {
                                                    val = -32768;
                                                }
                                                if (val < 0)
                                                {
                                                    val = val | 0x8000;
                                                }
                                                convbuffer[ptr]     = (byte)(val);
                                                convbuffer[ptr + 1] = (byte)(((uint)val) >> 8);
                                                ptr += 2 * (Info.Channels);
                                            }
                                        }

                                        //                  System.out.write(convbuffer, 0, 2*vi.channels*bout);
                                        //throw(new NotImplementedException("ccccccccc"));
                                        //OutputBuffer.Write(convbuffer, 0, 2 * Info.channels * bout);
                                        InfoHolder.BufferLength = 2 * Info.Channels * convsize;
                                        yield return(new ArraySegment <byte>(convbuffer, 0, 2 * Info.Channels * bout));

                                        // tell libvorbis how
                                        // many samples we
                                        // actually consumed
                                        DspState.synthesis_read(bout);
                                    }
                                }
                            }
                            if (Page.EndOfStream)
                            {
                                eos = true;
                            }
                        }
                    }

                    if (!eos)
                    {
                        index  = SyncState.Buffer(4096);
                        buffer = SyncState.Data;
                        bytes  = OggBaseStream.Read(buffer, index, 4096);
                        SyncState.Wrote(bytes);
                        if (bytes == 0)
                        {
                            eos = true;
                        }
                    }
                }

                // clean up this logical bitstream; before exit we see if we're
                // followed by another [chained]

                StreamState.Clear();

                // ogg_page and ogg_packet structs always point to storage in
                // libvorbis.  They're never freed or manipulated directly

                Block.clear();
                DspState.clear();
                Info.Clear();                 // must be called last

                yield return(new ArraySegment <byte>());
            }

            // OK, clean up the framer
            SyncState.Clear();
        }
Exemplo n.º 2
0
        public OggSound(Stream OggStream)
        {
            IsReady       = false;
            DecoderThread = new Thread(() =>
            {
                Debug.WriteLine("SOUND DECODER STARTED!");

                InfoHolder = new InfoHolderClass();

                if (OggStream.CanSeek)
                {
                    var Data       = new BinaryReader(OggStream).ReadBytes((int)OggStream.Length);
                    int StartIndex = 0;
                    while (true)
                    {
                        int Pos = Array.IndexOf(Data, (byte)'O', StartIndex);
                        if (Pos < 0)
                        {
                            break;
                        }
                        if (
                            (Data[Pos + 0] == 'O') &&
                            (Data[Pos + 1] == 'g') &&
                            (Data[Pos + 2] == 'g') &&
                            (Data[Pos + 3] == 'S') &&
                            (Data[Pos + 4] == '\0') &&
                            ((Data[Pos + 5] & 0x04) != 0)
                            )
                        {
                            InfoHolder.LastGranulePos = Page._ReadGranulePosition(Data, Pos + 6);
                            break;
                        }
                        StartIndex = Pos + 1;
                    }
                    if (InfoHolder.LastGranulePos == 0)
                    {
                        throw (new Exception("Can't find the decoded length of the Ogg Stream (LastGranulePos)"));
                    }
                    OggStream.Position = 0;
                }

                //var Stopwatch = new Stopwatch();
                //Stopwatch.Start();
                OggReader = DecodeTo(OggStream, InfoHolder).GetEnumerator();
                OggReader.MoveNext();
                if (OggReader.Current.Array != null)
                {
                    throw (new Exception("Invalid"));
                }

                //WaitAtLeastBuffer(4);

                DynamicSoundEffect = new DynamicSoundEffectInstance(InfoHolder.Info.Rate, (InfoHolder.Info.Channels == 2) ? AudioChannels.Stereo : AudioChannels.Mono);
                //Debug.WriteLine("FORMAT: channels:{0}, rate:{1}", InfoHolder.Info.channels, InfoHolder.Info.rate);
                //DynamicSoundEffect = new DynamicSoundEffectInstance(22050, AudioChannels.Mono);
                DynamicSoundEffect.BufferNeeded += new EventHandler <EventArgs>(DynamicSoundEffect_BufferNeeded);
                //Debug.WriteLine("START TIME: {0}", Stopwatch.ElapsedMilliseconds);
                //FillBuffer();
                //WaitAtLeastBuffer(4);
                EnqueueBuffer();
                EnqueueBuffer();

                Debug.WriteLine("SOUND DECODER ISREADY!");

                IsReady = true;

                while (true)
                {
                    if (Ended)
                    {
                        return;
                    }
                    if (Stopped)
                    {
                        return;
                    }

                    if (!EnqueueBuffer())
                    {
                        return;
                    }
                    Thread.Sleep(1);
                }
            });
            DecoderThread.Start();
        }