public FlacSubFrameConstant(FlacBitReader reader, FlacFrameHeader header, FlacSubFrameData data, int bitsPerSample)
: base(header)
{
unchecked
{
var value = (int)reader.ReadBits(bitsPerSample);
data.DestinationBuffer.Span.Fill(value);
}
}
public unsafe FlacSubFrameLPC(FlacBitReader reader, FlacFrameHeader header, FlacSubFrameData data, int bps, int order)
: base(header)
{
//warmup
_warmup = new int[FlacConstant.MAX_LPC_ORDER];
for (int i = 0; i < order; i++)
{
_warmup[i] = data.residualBuffer[i] = reader.ReadBitsSigned(bps);
}
//header
int u32 = (int)reader.ReadBits(FlacConstant.SUBFRAME_LPC_QLP_COEFF_PRECISION_LEN);
if (u32 == (1 << FlacConstant.SUBFRAME_LPC_QLP_COEFF_PRECISION_LEN) - 1)
{
Debug.WriteLine("Invalid FlacLPC qlp coeff precision.");
return; //return false;
}
_qlpCoeffPrecision = u32 + 1;
int level = reader.ReadBitsSigned(FlacConstant.SUBFRAME_LPC_QLP_SHIFT_LEN);
if (level < 0)
throw new Exception("negative shift");
_lpcShiftNeeded = level;
_qlpCoeffs = new int[FlacConstant.MAX_LPC_ORDER];
//qlp coeffs
for (int i = 0; i < order; i++)
{
_qlpCoeffs[i] = reader.ReadBitsSigned(_qlpCoeffPrecision);
}
//QLPCoeffs = coeffs;
Residual = new FlacResidual(reader, header, data, order);
for (int i = 0; i < order; i++)
{
data.destBuffer[i] = data.residualBuffer[i];
}
if (bps + _qlpCoeffPrecision + CSMath.ILog(order) <= 32)
{
if (bps <= 16 && _qlpCoeffPrecision <= 16)
RestoreLPCSignal(data.residualBuffer + order, data.destBuffer + order, header.BlockSize - order, order); //Restore(data.residualBuffer + order, data.destBuffer, Header.BlockSize - order, order, order);
else
RestoreLPCSignal(data.residualBuffer + order, data.destBuffer + order, header.BlockSize - order, order);
}
else
{
RestoreLPCSignalWide(data.residualBuffer + order, data.destBuffer + order, header.BlockSize - order, order);//RestoreWide(data.residualBuffer + order, data.destBuffer, Header.BlockSize - order, order, order);
}
//Warmup = warmup;
}
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) + 1;
if (coefPrecision == 0x0F)
{
Debug.WriteLine("Invalid linear predictor coefficients' precision. Must not be 0x0F.");
return;
}
int shiftNeeded = reader.ReadBitsSigned(5);
if (shiftNeeded < 0)
throw new FlacException("\"Quantized linear predictor coefficient shift needed.\" 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
}
public unsafe FlacSubFrameFixed(FlacBitReader reader, FlacFrameHeader header, FlacSubFrameData data, int bps, int order)
: base(header)
{
for (int i = 0; i < order; i++)
{
data.residualBuffer[i] = data.destBuffer[i] = reader.ReadBitsSigned(bps);
}
Residual = new FlacResidual(reader, header, data, order);
RestoreSignal(data, header.BlockSize - order, order);
}
public unsafe FlacSubFrameFixed(FlacBitReader reader, FlacFrameHeader header, FlacSubFrameData data, int bps, int order)
: base(header)
{
for (int i = 0; i < order; i++)
{
data.residualBuffer[i] = data.destBuffer[i] = reader.ReadBitsSigned(bps);
}
Residual = new FlacResidual(reader, header, data, order);
RestoreSignal(data, header.BlockSize - order, order);
}
public FlacSubFrameLPC(FlacBitReader reader, FlacFrameHeader header, FlacSubFrameData data, int bitsPerSample,
int order)
: base(header)
{
unchecked
{
var resi = data.ResidualBuffer.Span;
var dest = data.DestinationBuffer.Span;
for (var i = 0; i < order; i++)
{
resi[i] = reader.ReadBitsSigned(bitsPerSample);
}
var 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;
var 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 (var i = 0; i < order; i++)
{
q[i] = reader.ReadBitsSigned(coefPrecision);
}
//decode the residual
new FlacResidual(reader, header, data, order);
resi.Slice(0, order).CopyTo(dest);
var blockSizeToProcess = header.BlockSize - order;
if (bitsPerSample + coefPrecision + Log2(order) <= 32)
{
RestoreLPCSignal32(resi, dest, blockSizeToProcess, order, q, shiftNeeded);
}
else
{
RestoreLPCSignal64(resi, dest, blockSizeToProcess, order, q, shiftNeeded);
}
}
}
private void Decode(Stream stream, FlacMetadataStreamInfo streamInfo)
{
Header = new FlacFrameHeader(stream, streamInfo);
_stream = stream;
_streamInfo = streamInfo;
HasError = Header.HasError;
if (!HasError)
{
ReadSubFrames();
FreeBuffers();
}
}
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 FlacResidual(FlacBitReader reader, FlacFrameHeader header, FlacSubFrameData data, int order)
{
var codingMethod = (FlacResidualCodingMethod)reader.ReadBits(2); // 2 Bit
if (codingMethod == FlacResidualCodingMethod.PartitionedRice || codingMethod == FlacResidualCodingMethod.PartitionedRice2)
{
var partitionOrder = (int)reader.ReadBits(4); //"Partition order." see https://xiph.org/flac/format.html#partitioned_rice and https://xiph.org/flac/format.html#partitioned_rice2
FlacPartitionedRice.ProcessResidual(reader, header, data, order, partitionOrder, codingMethod);
}
else
{
throw new FlacException("Not supported RICE-Coding-Method. Stream unparseable!", FlacLayer.SubFrame);
}
}
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 FlacSubFrameVerbatim(FlacBitReader reader, FlacFrameHeader header, FlacSubFrameData data,
int bitsPerSample)
: base(header)
{
unchecked
{
var dest = data.DestinationBuffer.Span;
var resi = data.ResidualBuffer.Span;
for (var i = 0; i < header.BlockSize; i++)
{
var x = (int)reader.ReadBits(bitsPerSample);
dest[i] = resi[i] = x;
}
}
}
public FlacSubFrameFixed(FlacBitReader reader, FlacFrameHeader header, FlacSubFrameData data, int bitsPerSample,
int order)
: base(header)
{
unchecked
{
var resi = data.ResidualBuffer.Span;
var dest = data.DestinationBuffer.Span;
for (var i = 0; i < order; i++) //order = predictor order
{
resi[i] = dest[i] = reader.ReadBitsSigned(bitsPerSample);
}
new FlacResidual(reader, header, data, order); //necessary for decoding
RestoreSignal(data, header.BlockSize - order, order);
}
}
public unsafe bool ProcessResidual(FlacBitReader reader, FlacFrameHeader header, FlacSubFrameData data, int order)
{
data.Content.UpdateSize(PartitionOrder);
int porder = PartitionOrder;
FlacEntropyCoding codingMethod = CodingMethod;
int psize = header.BlockSize >> porder;
int res_cnt = psize - order;
int ricelength = 4 + (int)codingMethod; //4bit = RICE I | 5bit = RICE II
//residual
int j = order;
int *r = data.residualBuffer + j;
int partitioncount = 1 << porder;
for (int p = 0; p < partitioncount; p++)
{
if (p == 1)
{
res_cnt = psize;
}
int n = Math.Min(res_cnt, header.BlockSize - j);
int k = Content.parameters[p] = (int)reader.ReadBits(ricelength);
if (k == (1 << ricelength) - 1)
{
k = (int)reader.ReadBits(5);
for (int i = n; i > 0; i--)
{
*(r) = reader.ReadBitsSigned((int)k);
}
}
else
{
ReadFlacRiceBlock(reader, n, (int)k, r);
r += n;
}
j += n;
}
return(true);
}
public unsafe bool ProcessResidual(FlacBitReader reader, FlacFrameHeader header, FlacSubFrameData data, int order)
{
data.Content.UpdateSize(PartitionOrder);
int porder = PartitionOrder;
FlacEntropyCoding codingMethod = CodingMethod;
int psize = header.BlockSize >> porder;
int res_cnt = psize - order;
int ricelength = 4 + (int)codingMethod; //4bit = RICE I | 5bit = RICE II
//residual
int j = order;
int* r = data.residualBuffer + j;
int partitioncount = 1 << porder;
for (int p = 0; p < partitioncount; p++)
{
if (p == 1) res_cnt = psize;
int n = Math.Min(res_cnt, header.BlockSize - j);
int k = Content.parameters[p] = (int)reader.ReadBits(ricelength);
if (k == (1 << ricelength) - 1)
{
k = (int)reader.ReadBits(5);
for (int i = n; i > 0; i--)
{
*(r) = reader.ReadBitsSigned((int)k);
}
}
else
{
ReadFlacRiceBlock(reader, n, (int)k, r);
r += n;
}
j += n;
}
return true;
}
private unsafe void Decode(Stream stream, FlacMetadataStreamInfo streamInfo)
{
Header = new FlacFrameHeader(stream, streamInfo);
_stream = stream;
_streamInfo = streamInfo;
HasError = Header.HasError;
if (!HasError)
{
if (_destBuffer == null || _destBuffer.Length < (Header.Channels * Header.BlockSize))
{
_destBuffer = new int[Header.Channels * Header.BlockSize];
}
if (_residualBuffer == null || _residualBuffer.Length < (Header.Channels * Header.BlockSize))
_residualBuffer = new int[Header.Channels * Header.BlockSize];
fixed(int *ptrDestBuffer = _destBuffer, ptrResidualBuffer = _residualBuffer)
{
ReadSubFrames(ptrDestBuffer, ptrResidualBuffer);
}
//FreeBuffers();
}
}
public static unsafe 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 & 0x08) != 0) //001000 = 0x08
{
order = (int) (subframeType & 0x07);
subFrame = new FlacSubFrameFixed(reader, header, data, bitsPerSample, order);
}
else if ((subframeType & 0x20) != 0) //100000 = 0x20
{
order = (int) (subframeType & 0x1F) + 1;
subFrame = new FlacSubFrameLPC(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;
}
protected FlacSubFrameBase(FlacFrameHeader header)
{
#if FLAC_DEBUG
Header = header;
#endif
}
protected FlacSubFrameBase(FlacFrameHeader header)
{
Header = header;
}
private unsafe bool IsFrame(ref byte* buffer, FlacMetadataStreamInfo streamInfo, FlacFrameHeader baseHeader, out FlacFrameHeader header)
{
header = new FlacFrameHeader(ref buffer, streamInfo, true, false);
return !header.HasError;
}
/// <summary>
/// Indicates whether the format of the current <see cref="FlacFrameHeader"/> is equal to the format of another <see cref="FlacFrameHeader"/>.
/// </summary>
/// <param name="other">A <see cref="FlacFrameHeader"/> which provides the format to compare with the format of the current <see cref="FlacFrameHeader"/>.</param>
/// <returns><c>true</c> if the format of the current <see cref="FlacFrameHeader"/> is equal to the format of the <paramref name="other"/> <see cref="FlacFrameHeader"/>.</returns>
public bool IsFormatEqualTo(FlacFrameHeader other)
{
return(BitsPerSample == other.BitsPerSample &&
Channels == other.Channels &&
SampleRate == other.SampleRate);
}
public bool CompareTo(FlacFrameHeader header)
{
return (BitsPerSample == header.BitsPerSample &&
Channels == header.Channels &&
SampleRate == header.SampleRate);
}
public bool CompareTo(FlacFrameHeader header)
{
return(BitsPerSample == header.BitsPerSample &&
Channels == header.Channels &&
SampleRate == header.SampleRate);
}
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 & 0x08) != 0) //001000 = 0x08
{
order = (int)(subframeType & 0x07);
subFrame = new FlacSubFrameFixed(reader, header, data, bitsPerSample, order);
}
else if ((subframeType & 0x20) != 0) //100000 = 0x20
{
order = (int)(subframeType & 0x1F) + 1;
subFrame = new FlacSubFrameLPC(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);
}
private unsafe bool IsFrame(ref byte* buffer, FlacMetadataStreamInfo streamInfo, out FlacFrameHeader header)
{
header = new FlacFrameHeader(ref buffer, streamInfo, true, false);
return !header.HasError;
}
protected FlacSubFrameBase(FlacFrameHeader header)
{
}
private void Decode(Stream stream, FlacMetadataStreamInfo streamInfo)
{
Header = new FlacFrameHeader(stream, streamInfo);
_stream = stream;
_streamInfo = streamInfo;
HasError = Header.HasError;
if (!HasError)
{
ReadSubFrames();
FreeBuffers();
}
}
public unsafe FlacSubFrameLPC(FlacBitReader reader, FlacFrameHeader header, FlacSubFrameData data, int bps, int order)
: base(header)
{
//warmup
_warmup = new int[FlacConstant.MAX_LPC_ORDER];
for (int i = 0; i < order; i++)
{
_warmup[i] = data.residualBuffer[i] = reader.ReadBitsSigned(bps);
}
//header
int u32 = (int)reader.ReadBits(FlacConstant.SUBFRAME_LPC_QLP_COEFF_PRECISION_LEN);
if (u32 == (1 << FlacConstant.SUBFRAME_LPC_QLP_COEFF_PRECISION_LEN) - 1)
{
Debug.WriteLine("Invalid FlacLPC qlp coeff precision.");
return; //return false;
}
_qlpCoeffPrecision = u32 + 1;
int level = reader.ReadBitsSigned(FlacConstant.SUBFRAME_LPC_QLP_SHIFT_LEN);
if (level < 0)
{
throw new Exception("negative shift");
}
_lpcShiftNeeded = level;
_qlpCoeffs = new int[FlacConstant.MAX_LPC_ORDER];
//qlp coeffs
for (int i = 0; i < order; i++)
{
_qlpCoeffs[i] = reader.ReadBitsSigned(_qlpCoeffPrecision);
}
//QLPCoeffs = coeffs;
Residual = new FlacResidual(reader, header, data, order);
for (int i = 0; i < order; i++)
{
data.destBuffer[i] = data.residualBuffer[i];
}
if (bps + _qlpCoeffPrecision + CSMath.ILog(order) <= 32)
{
if (bps <= 16 && _qlpCoeffPrecision <= 16)
{
RestoreLPCSignal(data.residualBuffer + order, data.destBuffer + order, header.BlockSize - order, order); //Restore(data.residualBuffer + order, data.destBuffer, Header.BlockSize - order, order, order);
}
else
{
RestoreLPCSignal(data.residualBuffer + order, data.destBuffer + order, header.BlockSize - order, order);
}
}
else
{
RestoreLPCSignalWide(data.residualBuffer + order, data.destBuffer + order, header.BlockSize - order, order);//RestoreWide(data.residualBuffer + order, data.destBuffer, Header.BlockSize - order, order, order);
}
//Warmup = warmup;
}
/// <summary>
/// Indicates whether the format of the current <see cref="FlacFrameHeader"/> is equal to the format of another <see cref="FlacFrameHeader"/>.
/// </summary>
/// <param name="other">A <see cref="FlacFrameHeader"/> which provides the format to compare with the format of the current <see cref="FlacFrameHeader"/>.</param>
/// <returns><c>true</c> if the format of the current <see cref="FlacFrameHeader"/> is equal to the format of the <paramref name="other"/> <see cref="FlacFrameHeader"/>.</returns>
public bool IsFormatEqualTo(FlacFrameHeader other)
{
return (BitsPerSample == other.BitsPerSample &&
Channels == other.Channels &&
SampleRate == other.SampleRate);
}
public unsafe static FlacSubFrameBase GetSubFrame(FlacBitReader reader, FlacSubFrameData data, FlacFrameHeader header, int bps)
{
uint x;
int wastedBits = 0, totalBits = 0, order = 0;
x = reader.ReadBits(8);
bool haswastedBits = (x & 1) != 0;
x &= 0xFE; //1111 1110
if (haswastedBits)
{
int u = (int)reader.ReadUnary();
wastedBits = u + 1;
bps -= wastedBits;
totalBits = bps;
}
if ((x & 0x80) != 0)
{
Debug.WriteLine("Flacdecoder lost sync while reading FlacSubFrameHeader. [x & 0x80].");
return(null);
}
FlacSubFrameBase subFrame = null;
if ((x > 2 && x < 16) ||
(x > 24 && x < 64))
{
Debug.WriteLine("Invalid FlacSubFrameHeader. [" + x.ToString("x") + "]");
return(null);
}
else if (x == 0)
{
subFrame = new FlacSubFrameConstant(reader, header, data, bps);
}
else if (x == 2)
{
//verbatim
subFrame = new FlacSubFrameVerbatim(reader, header, data, bps);
}
else if (x >= 16 && x <= 24)
{
//fixed
order = (int)((x >> 1) & 7);
subFrame = new FlacSubFrameFixed(reader, header, data, bps, order);
}
else if (x >= 64)
{
//lpc
order = (int)(((x >> 1) & 31) + 1);
subFrame = new FlacSubFrameLPC(reader, header, data, bps, order);
}
else
{
Debug.WriteLine("Invalid Flac-SubframeType: x = " + x + ".");
return(null);
}
if (haswastedBits)
{
int *ptrDest = data.destBuffer;
for (int i = 0; i < header.BlockSize; i++)
{
*(ptrDest++) <<= wastedBits;
}
}
//System.Diagnostics.Debug.WriteLine(subFrame.GetType().Name);
if (subFrame != null)
{
subFrame.WastedBits = wastedBits;
}
else
{
Debug.WriteLine("Unknown error while reading FlacSubFrameHeader");
}
return(subFrame);
}
protected FlacSubFrameBase(FlacFrameHeader header)
{
#if FLAC_DEBUG
Header = header;
#endif
}
public static FlacSubFrameBase GetSubFrame(FlacBitReader reader, FlacSubFrameData data, FlacFrameHeader header,
int bitsPerSample)
{
unchecked
{
int wastedBits = 0, order;
var 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);
}
var hasWastedBits = (firstByte & 1) != 0; //Wasted bits-per-sample' flag
if (hasWastedBits)
{
var 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($"Invalid Flac-SubframeType. SubframeType: 0x{subframeType:x}.");
return(null);
}
if (hasWastedBits)
{
var destination = data.DestinationBuffer.Span;
for (var i = 0; i < header.BlockSize; i++)
{
destination[i] <<= wastedBits;
}
}
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
}
private unsafe List<FlacFrameInformation> ScanThisShit(FlacMetadataStreamInfo streamInfo)
{
Stream stream = _stream;
//if (!(stream is BufferedStream))
// stream = new BufferedStream(stream);
byte[] buffer = new byte[BufferSize];
stream.Position = 4; //fLaC
//skip the metadata
FlacMetadata.SkipMetadata(stream);
List<FlacFrameInformation> frames = new List<FlacFrameInformation>();
FlacFrameInformation frameInfo = new FlacFrameInformation();
frameInfo.IsFirstFrame = true;
FlacFrameHeader baseHeader = null;
while (true)
{
int read = stream.Read(buffer, 0, buffer.Length);
if (read <= FlacConstant.FrameHeaderSize)
break;
fixed (byte* bufferPtr = buffer)
{
byte* ptr = bufferPtr;
//for (int i = 0; i < read - FlacConstant.FrameHeaderSize; i++)
while ((bufferPtr + read - FlacConstant.FrameHeaderSize) > ptr)
{
if (*ptr++ == 0xFF && (*ptr & 0xF8) == 0xF8) //check sync
{
byte* ptrSafe = ptr;
ptr--;
FlacFrameHeader tmp;
if (IsFrame(ref ptr, streamInfo, out tmp))
{
FlacFrameHeader header = tmp;
if (frameInfo.IsFirstFrame)
{
baseHeader = header;
frameInfo.IsFirstFrame = false;
}
if (baseHeader != null && baseHeader.IsFormatEqualTo(header))
{
frameInfo.StreamOffset = stream.Position - read + ((ptrSafe - 1) - bufferPtr);
frameInfo.Header = header;
frames.Add(frameInfo);
frameInfo.SampleOffset += header.BlockSize;
}
else
{
ptr = ptrSafe;
}
}
else
{
ptr = ptrSafe;
}
}
}
}
stream.Position -= FlacConstant.FrameHeaderSize;
}
return frames;
}
public static unsafe FlacSubFrameBase GetSubFrame(FlacBitReader reader, FlacSubFrameData data, FlacFrameHeader header, int bps)
{
uint x;
int wastedBits = 0, totalBits = 0, order = 0;
x = reader.ReadBits(8);
bool haswastedBits = (x & 1) != 0;
x &= 0xFE; //1111 1110
if (haswastedBits)
{
int u = (int)reader.ReadUnary();
wastedBits = u + 1;
bps -= wastedBits;
totalBits = bps;
}
if ((x & 0x80) != 0)
{
Debug.WriteLine("Flacdecoder lost sync while reading FlacSubFrameHeader. [x & 0x80].");
return null;
}
FlacSubFrameBase subFrame = null;
if ((x > 2 && x < 16) ||
(x > 24 && x < 64))
{
Debug.WriteLine("Invalid FlacSubFrameHeader. [" + x.ToString("x") + "]");
return null;
}
else if (x == 0)
{
subFrame = new FlacSubFrameConstant(reader, header, data, bps);
}
else if (x == 2)
{
//verbatim
subFrame = new FlacSubFrameVerbatim(reader, header, data, bps);
}
else if (x >= 16 && x <= 24)
{
//fixed
order = (int)((x >> 1) & 7);
subFrame = new FlacSubFrameFixed(reader, header, data, bps, order);
}
else if (x >= 64)
{
//lpc
order = (int)(((x >> 1) & 31) + 1);
subFrame = new FlacSubFrameLPC(reader, header, data, bps, order);
}
else
{
Debug.WriteLine("Invalid Flac-SubframeType: x = " + x + ".");
return null;
}
if (haswastedBits)
{
int* ptrDest = data.destBuffer;
for (int i = 0; i < header.BlockSize; i++)
{
*(ptrDest++) <<= wastedBits;
}
}
//System.Diagnostics.Debug.WriteLine(subFrame.GetType().Name);
if (subFrame != null)
subFrame.WastedBits = wastedBits;
else
Debug.WriteLine("Unknown error while reading FlacSubFrameHeader");
return subFrame;
}
