private unsafe void ReadSubFrames() { List <FlacSubFrameBase> subFrames = new List <FlacSubFrameBase>(); //alocateOutput var data = AllocOuputMemory(); _subFrameData = data; byte[] buffer = new byte[0x20000]; if ((_streamInfo.MaxFrameSize * Header.Channels * Header.BitsPerSample * 2 >> 3) > buffer.Length) { buffer = new byte[(_streamInfo.MaxFrameSize * Header.Channels * Header.BitsPerSample * 2 >> 3) - FlacConstant.FrameHeaderSize]; } int read = _stream.Read(buffer, 0, (int)Math.Min(buffer.Length, _stream.Length - _stream.Position)); fixed(byte *ptrBuffer = buffer) { FlacBitReader reader = new FlacBitReader(ptrBuffer, 0); for (int c = 0; c < Header.Channels; c++) { int bitsPerSample = Header.BitsPerSample; if (Header.ChannelAssignment == ChannelAssignment.MidSide || Header.ChannelAssignment == ChannelAssignment.LeftSide) { bitsPerSample += c; } else if (Header.ChannelAssignment == ChannelAssignment.RightSide) { bitsPerSample += 1 - c; } var subframe = FlacSubFrameBase.GetSubFrame(reader, data[c], Header, bitsPerSample); subFrames.Add(subframe); } reader.Flush(); //Zero-padding to byte alignment. //footer Crc16 = (short)reader.ReadBits(16); _stream.Position -= read - reader.Position; MapToChannels(_subFrameData); } #if FLAC_DEBUG _subFrames = subFrames.AsReadOnly(); #endif }
public unsafe FlacSubFrameFixed(FlacBitReader reader, FlacFrameHeader header, FlacSubFrameData data, int bitsPerSample, int order) : base(header) { for (int i = 0; i < order; i++) //order = predictor order { data.ResidualBuffer[i] = data.DestinationBuffer[i] = reader.ReadBitsSigned(bitsPerSample); } var residual = new FlacResidual(reader, header, data, order); //necessary for decoding RestoreSignal(data, header.BlockSize - order, order); #if FLAC_DEBUG Residual = residual; #endif }
/// <summary> /// Initializes the properties of the <see cref="FlacMetadata"/> by reading them from the <paramref name="stream"/>. /// </summary> /// <param name="stream">The stream which contains the metadata.</param> protected override unsafe void InitializeByStream(Stream stream) { //http://flac.sourceforge.net/format.html#metadata_block_streaminfo var reader = new BinaryReader(stream, Encoding.ASCII); try { MinBlockSize = reader.ReadInt16(); MaxBlockSize = reader.ReadInt16(); } catch (IOException e) { throw new FlacException(e, FlacLayer.Metadata); } const int bytesToRead = (240 / 8) - 16; byte[] buffer = reader.ReadBytes(bytesToRead); if (buffer.Length != bytesToRead) { throw new FlacException(new EndOfStreamException("Could not read StreamInfo-content"), FlacLayer.Metadata); } fixed(byte *b = buffer) { var bitreader = new FlacBitReader(b, 0); MinFrameSize = (int)bitreader.ReadBits(24); MaxFrameSize = (int)bitreader.ReadBits(24); SampleRate = (int)bitreader.ReadBits(20); Channels = 1 + (int)bitreader.ReadBits(3); BitsPerSample = 1 + (int)bitreader.ReadBits(5); TotalSamples = (long)bitreader.ReadBits64(36); Md5 = new String(reader.ReadChars(16)); } }
private unsafe bool ParseHeader(ref byte *headerBuffer, FlacMetadataStreamInfo streamInfo) { const string loggerLocation = "FlacFrameHeader.ParseHeader(byte*, FlacMetadataStreamInfo)"; int val; if (headerBuffer[0] == 0xFF && headerBuffer[1] >> 1 == 0x7C) //sync bits { if ((headerBuffer[1] & 0x02) != 0) { Error("Invalid FlacFrame. Reservedbit_0 is 1", loggerLocation); return(false); } byte * __headerbufferPtr = headerBuffer; FlacBitReader reader = new FlacBitReader(__headerbufferPtr, 0); #region blocksize //blocksize val = headerBuffer[2] >> 4; int blocksize = -1; if (val == 0) { Error("Invalid Blocksize value: 0", loggerLocation); return(false); } if (val == 1) { blocksize = 192; } else if (val >= 2 && val <= 5) { blocksize = 576 << (val - 2); } else if (val == 6 || val == 7) { _blocksizeHint = val; } else if (val >= 8 && val <= 15) { blocksize = 256 << (val - 8); } else { Error("Invalid Blocksize value: " + val, loggerLocation); return(false); } BlockSize = blocksize; #endregion blocksize #region samplerate //samplerate val = headerBuffer[2] & 0x0F; int sampleRate = -1; if (val == 0) { if (streamInfo != null) { sampleRate = streamInfo.SampleRate; } else { Error("Missing Samplerate. Samplerate Index = 0 && streamInfoMetaData == null.", loggerLocation); return(false); } } else if (val >= 1 && val <= 11) { sampleRate = FlacConstant.SampleRateTable[val]; } else if (val >= 12 && val <= 14) { _sampleRateHint = val; } else { Error("Invalid SampleRate value: " + val, loggerLocation); return(false); } SampleRate = sampleRate; #endregion samplerate #region channels val = headerBuffer[3] >> 4; //cc: unsigned int channels; if ((val & 8) != 0) { channels = 2; if ((val & 7) > 2 || (val & 7) < 0) { Error("Invalid ChannelAssignment", loggerLocation); return(false); } ChannelAssignment = (ChannelAssignment)((val & 7) + 1); } else { channels = val + 1; ChannelAssignment = ChannelAssignment.Independent; } Channels = channels; #endregion channels #region bitspersample val = (headerBuffer[3] & 0x0E) >> 1; int bitsPerSample; if (val == 0) { if (streamInfo != null) { bitsPerSample = streamInfo.BitsPerSample; } else { Error("Missing BitsPerSample. Index = 0 && streamInfoMetaData == null.", loggerLocation); return(false); } } else if (val == 3 || val >= 7 || val < 0) { Error("Invalid BitsPerSampleIndex", loggerLocation); return(false); } else { bitsPerSample = FlacConstant.BitPerSampleTable[val]; } BitsPerSample = bitsPerSample; #endregion bitspersample if ((headerBuffer[3] & 0x01) != 0) // reserved bit -> 0 { Error("Invalid FlacFrame. Reservedbit_1 is 1", loggerLocation); return(false); } reader.ReadBits(32); //skip the first 4 bytes since they got already processed //BYTE 4 #region utf8 //variable blocksize if ((headerBuffer[1] & 0x01) != 0 || (streamInfo != null && streamInfo.MinBlockSize != streamInfo.MaxBlockSize)) { ulong samplenumber; if (reader.ReadUTF8_64(out samplenumber) && samplenumber != ulong.MaxValue) { BlockingStrategy = BlockingStrategy.VariableBlockSize; SampleNumber = (long)samplenumber; } else { Error("Invalid UTF8 Samplenumber coding.", loggerLocation); return(false); } } else //fixed blocksize { uint framenumber; if (reader.ReadUTF8_32(out framenumber) && framenumber != uint.MaxValue) { BlockingStrategy = BlockingStrategy.FixedBlockSize; FrameNumber = (int)framenumber; } else { Error("Invalid UTF8 Framenumber coding.", loggerLocation); return(false); } } #endregion utf8 #region read hints //blocksize am ende des frameheaders if (_blocksizeHint != 0) { val = (int)reader.ReadBits(8); if (_blocksizeHint == 7) { val = (val << 8) | (int)reader.ReadBits(8); } BlockSize = val + 1; } //samplerate if (_sampleRateHint != 0) { val = (int)reader.ReadBits(8); if (_sampleRateHint != 12) { val = (val << 8) | (int)reader.ReadBits(8); } if (_sampleRateHint == 12) { SampleRate = val * 1000; } else if (_sampleRateHint == 13) { SampleRate = val; } else { SampleRate = val * 10; } } #endregion read hints if (DoCrc) { var crc8 = Utils.CRC8.Instance.CalcCheckSum(reader.Buffer, 0, reader.Position); Crc8 = (byte)reader.ReadBits(8); if (Crc8 != crc8) { Error("CRC8 missmatch", loggerLocation); return(false); } } else { Crc8 = (byte)reader.ReadBits(8); } headerBuffer += reader.Position; return(true); } Error("Invalid Syncbits", loggerLocation); return(false); }
public unsafe static FlacSubFrameBase GetSubFrame(FlacBitReader reader, FlacSubFrameData data, FlacFrameHeader header, int bitsPerSample) { int wastedBits = 0, order; uint firstByte = reader.ReadBits(8); if ((firstByte & 0x80) != 0) //Zero bit padding, to prevent sync-fooling string of 1s { Debug.WriteLine("Flacdecoder subframe-header got no zero-bit padding."); return(null); } bool hasWastedBits = (firstByte & 1) != 0; //Wasted bits-per-sample' flag if (hasWastedBits) { int k = (int)reader.ReadUnary(); wastedBits = k + 1; //"k-1" follows -> add 1 bitsPerSample -= wastedBits; } FlacSubFrameBase subFrame; var subframeType = (firstByte & 0x7E) >> 1; //0111 1110 if (subframeType == 0) //000000 { subFrame = new FlacSubFrameConstant(reader, header, data, bitsPerSample); } else if (subframeType == 1) //000001 { subFrame = new FlacSubFrameVerbatim(reader, header, data, bitsPerSample); } else if ((subframeType & 0x20) != 0) //100000 = 0x20 { order = (int)(subframeType & 0x1F) + 1; subFrame = new FlacSubFrameLPC(reader, header, data, bitsPerSample, order); } else if ((subframeType & 0x08) != 0) //001000 = 0x08 { order = (int)(subframeType & 0x07); if (order > 4) { return(null); } subFrame = new FlacSubFrameFixed(reader, header, data, bitsPerSample, order); } else { Debug.WriteLine(String.Format("Invalid Flac-SubframeType. SubframeType: 0x{0:x}.", subframeType)); return(null); } if (hasWastedBits) { int *destination = data.DestinationBuffer; for (int i = 0; i < header.BlockSize; i++) { *(destination++) <<= wastedBits; } } #if FLAC_DEBUG subFrame.WastedBits = wastedBits; #endif return(subFrame); }
public unsafe FlacSubFrameLPC(FlacBitReader reader, FlacFrameHeader header, FlacSubFrameData data, int bitsPerSample, int order) : base(header) { var warmup = new int[order]; for (int i = 0; i < order; i++) { warmup[i] = data.ResidualBuffer[i] = reader.ReadBitsSigned(bitsPerSample); } int coefPrecision = (int)reader.ReadBits(4); if (coefPrecision == 0x0F) { throw new FlacException("Invalid \"quantized linear predictor coefficients' precision in bits\" was invalid. Must not be 0x0F.", FlacLayer.SubFrame); } coefPrecision += 1; int shiftNeeded = reader.ReadBitsSigned(5); if (shiftNeeded < 0) { throw new FlacException("'\"Quantized linear predictor coefficient shift needed in bits\" was negative.", FlacLayer.SubFrame); } var q = new int[order]; for (int i = 0; i < order; i++) { q[i] = reader.ReadBitsSigned(coefPrecision); } //decode the residual var residual = new FlacResidual(reader, header, data, order); for (int i = 0; i < order; i++) { data.DestinationBuffer[i] = data.ResidualBuffer[i]; } int *residualBuffer0 = data.ResidualBuffer + order; int *destinationBuffer0 = data.DestinationBuffer + order; int blockSizeToProcess = header.BlockSize - order; if (bitsPerSample + coefPrecision + Log2(order) <= 32) { RestoreLPCSignal32(residualBuffer0, destinationBuffer0, blockSizeToProcess, order, q, shiftNeeded); } else { RestoreLPCSignal64(residualBuffer0, destinationBuffer0, blockSizeToProcess, order, q, shiftNeeded); } #if FLAC_DEBUG QLPCoeffPrecision = coefPrecision; LPCShiftNeeded = shiftNeeded; Warmup = warmup; Residual = residual; QLPCoeffs = q; #endif }