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 }
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 }