1308 lines
52 KiB
C#

// *****************************************************************************
// E R I S A - L i b r a r y
// -----------------------------------------------------------------------------
// Copyright (C) 2002-2007 Leshade Entis, Entis-soft. All rights reserved.
// *****************************************************************************
//
// C# port by morkt
//
using System;
using System.Diagnostics;
using GameRes.Utility;
namespace GameRes.Formats.Entis
{
internal class MioInfoHeader
{
public int Version;
public CvType Transformation;
public EriCode Architecture;
public int ChannelCount;
public uint SamplesPerSec;
public uint BlocksetCount;
public int SubbandDegree;
public uint AllSampleCount;
public uint LappedDegree;
public uint BitsPerSample;
}
internal class MioDataHeader
{
public byte Version;
public byte Flags;
public uint SampleCount;
}
internal struct EriSinCos
{
public float rSin;
public float rCos;
}
internal class MioDecoder
{
MioInfoHeader m_mioih;
uint m_nBufLength = 0;
int[] m_ptrBuffer1;
int[] m_ptrBuffer2;
sbyte[] m_ptrBuffer3;
byte[] m_ptrBuffer4;
byte[] m_ptrDivisionTable;
byte[] m_ptrRevolveCode;
int[] m_ptrWeightCode;
int[] m_ptrCoefficient;
float[] m_ptrMatrixBuf;
float[] m_ptrInternalBuf;
float[] m_ptrWorkBuf;
float[] m_ptrWeightTable;
float[] m_ptrLastDCT;
int m_ptrNextDivision;
int m_ptrNextRevCode;
int m_ptrNextWeight;
int m_ptrNextCoefficient;
int m_ptrNextSource;
int m_ptrLastDCTBuf;
int m_nSubbandDegree;
int m_nDegreeNum;
EriSinCos[] m_pRevolveParam;
readonly int[] m_nFrequencyPoint = new int[7];
const int MIN_DCT_DEGREE = 2;
const int MAX_DCT_DEGREE = 12;
static MioDecoder ()
{
eriInitializeMatrix();
}
public MioDecoder (MioInfoHeader info)
{
m_nBufLength = 0;
m_mioih = info;
if (!Initialize())
throw new InvalidFormatException();
}
bool Initialize ()
{
if ((m_mioih.ChannelCount != 1) && (m_mioih.ChannelCount != 2))
{
return false;
}
if (m_mioih.Transformation == CvType.Lossless_ERI)
{
if (m_mioih.Architecture != EriCode.RunlengthHuffman)
{
return false;
}
if ((m_mioih.BitsPerSample != 8) && (m_mioih.BitsPerSample != 16))
{
return false;
}
}
else if ((m_mioih.Transformation == CvType.LOT_ERI)
|| (m_mioih.Transformation == CvType.LOT_ERI_MSS))
{
if ((m_mioih.Architecture != EriCode.RunlengthGamma)
&& (m_mioih.Architecture != EriCode.RunlengthHuffman)
&& (m_mioih.Architecture != EriCode.Nemesis))
{
return false;
}
if (m_mioih.BitsPerSample != 16)
{
return false;
}
if ((m_mioih.SubbandDegree < 8) || (m_mioih.SubbandDegree > MAX_DCT_DEGREE))
{
return false;
}
if (m_mioih.LappedDegree != 1)
{
return false;
}
int subband = (sizeof(float) << m_mioih.SubbandDegree) / sizeof(float);
int block_size = m_mioih.ChannelCount * subband;
m_ptrBuffer1 = new int[block_size];
m_ptrMatrixBuf = new float[block_size];
m_ptrInternalBuf = new float[block_size];
m_ptrWorkBuf = new float[subband];
m_ptrWeightTable = new float[subband];
uint nBlocksetSamples = (uint)(m_mioih.ChannelCount << m_mioih.SubbandDegree);
uint nLappedSamples = nBlocksetSamples * m_mioih.LappedDegree;
if (nLappedSamples > 0)
{
m_ptrLastDCT = new float[nLappedSamples];
}
InitializeWithDegree (m_mioih.SubbandDegree);
}
else
{
return false;
}
return true;
}
public bool DecodeSound (ERISADecodeContext context, MioDataHeader datahdr, byte[] ptrWaveBuf, int wave_pos)
{
context.FlushBuffer();
if (m_mioih.Transformation == CvType.Lossless_ERI)
{
if (m_mioih.BitsPerSample == 8)
{
return DecodeSoundPCM8 (context, datahdr, ptrWaveBuf, wave_pos);
}
else if (m_mioih.BitsPerSample == 16)
{
return DecodeSoundPCM16 (context, datahdr, ptrWaveBuf, wave_pos);
}
}
else if ((m_mioih.Transformation == CvType.LOT_ERI)
|| (m_mioih.Transformation == CvType.LOT_ERI_MSS))
{
if ((m_mioih.ChannelCount != 2) || (m_mioih.Transformation == CvType.LOT_ERI))
{
return DecodeSoundDCT (context, datahdr, ptrWaveBuf, wave_pos);
}
else
{
return DecodeSoundDCT_MSS (context, datahdr, ptrWaveBuf, wave_pos);
}
}
return false;
}
bool DecodeSoundPCM8 (ERISADecodeContext context, MioDataHeader datahdr, byte[] ptrWaveBuf, int wave_pos)
{
uint nSampleCount = datahdr.SampleCount;
if (nSampleCount > m_nBufLength)
{
m_ptrBuffer3 = new sbyte [nSampleCount * m_mioih.ChannelCount];
m_nBufLength = nSampleCount;
}
if (0 != (datahdr.Flags & MIO_LEAD_BLOCK))
{
(context as HuffmanDecodeContext).PrepareToDecodeERINACode();
}
uint nBytes = nSampleCount * (uint)m_mioih.ChannelCount;
if (context.DecodeBytes (m_ptrBuffer3, nBytes) < nBytes)
{
return false;
}
int ptrSrcBuf = 0; // (PBYTE) m_ptrBuffer3;
int nStep = m_mioih.ChannelCount;
for (int i = 0; i < m_mioih.ChannelCount; i ++ )
{
int ptrDstBuf = wave_pos + i;
sbyte bytValue = 0;
for (uint j = 0; j < nSampleCount; j++)
{
bytValue += m_ptrBuffer3[ptrSrcBuf++];
ptrWaveBuf[ptrDstBuf] = (byte)bytValue;
ptrDstBuf += nStep;
}
}
return true;
}
bool DecodeSoundPCM16 (ERISADecodeContext context, MioDataHeader datahdr, byte[] ptrWaveBuf, int wave_pos)
{
uint nSampleCount = datahdr.SampleCount;
uint nChannelCount = (uint)m_mioih.ChannelCount;
uint nAllSampleCount = nSampleCount * nChannelCount;
if (nSampleCount > m_nBufLength)
{
m_ptrBuffer3 = new sbyte[nAllSampleCount * sizeof(short)];
m_ptrBuffer4 = new byte[nAllSampleCount * sizeof(short)];
m_nBufLength = nSampleCount;
}
if (0 != (datahdr.Flags & MIO_LEAD_BLOCK))
{
(context as HuffmanDecodeContext).PrepareToDecodeERINACode();
}
uint nBytes = nAllSampleCount * sizeof(short);
if (context.DecodeBytes (m_ptrBuffer3, nBytes) < nBytes)
{
return false;
}
int pbytSrcBuf1, pbytSrcBuf2, pbytDstBuf;
for (int i = 0; i < m_mioih.ChannelCount; i++)
{
int nOffset = i * (int)nSampleCount * sizeof(short);
pbytSrcBuf1 = nOffset; // ((PBYTE) m_ptrBuffer3) + nOffset;
pbytSrcBuf2 = pbytSrcBuf1 + (int)nSampleCount; // pbytSrcBuf1 + nSampleCount;
pbytDstBuf = nOffset; // ((PBYTE) m_ptrBuffer4) + nOffset;
for (uint j = 0; j < nSampleCount; j ++)
{
sbyte bytLow = m_ptrBuffer3[pbytSrcBuf2 + j];
sbyte bytHigh = m_ptrBuffer3[pbytSrcBuf1 + j];
m_ptrBuffer4[pbytDstBuf + j * sizeof(short) + 0] = (byte)bytLow;
m_ptrBuffer4[pbytDstBuf + j * sizeof(short) + 1] = (byte)(bytHigh ^ (bytLow >> 7));
}
}
int ptrSrcBuf = 0; // (SWORD*) m_ptrBuffer4;
int nStep = m_mioih.ChannelCount;
for (int i = 0; i < m_mioih.ChannelCount; i++)
{
int ptrDstBuf = wave_pos + i*sizeof(short); // (SWORD*) ptrWaveBuf;
short wValue = 0;
short wDelta = 0;
for (uint j = 0; j < nSampleCount; j++)
{
wDelta += LittleEndian.ToInt16 (m_ptrBuffer4, ptrSrcBuf);
wValue += wDelta;
LittleEndian.Pack (wValue, ptrWaveBuf, ptrDstBuf); // *ptrDstBuf = wValue;
ptrSrcBuf += sizeof(short);
ptrDstBuf += nStep;
}
}
return true;
}
static readonly int[] FreqWidth = new int[7] { -6, -6, -5, -4, -3, -2, -1 };
void InitializeWithDegree (int nSubbandDegree)
{
m_pRevolveParam = eriCreateRevolveParameter (nSubbandDegree);
for (int i = 0, j = 0; i < 7; i ++)
{
int nFrequencyWidth = 1 << (nSubbandDegree + FreqWidth[i]);
m_nFrequencyPoint[i] = j + (nFrequencyWidth / 2);
j += nFrequencyWidth;
}
m_nSubbandDegree = nSubbandDegree;
m_nDegreeNum = 1 << nSubbandDegree;
}
const uint MIO_LEAD_BLOCK = 0x01;
bool DecodeSoundDCT (ERISADecodeContext context, MioDataHeader datahdr, byte[] ptrWaveBuf, int wave_pos)
{
uint i, j, k;
uint nDegreeWidth = 1u << m_mioih.SubbandDegree;
uint nSampleCount = (datahdr.SampleCount + nDegreeWidth - 1) & ~(nDegreeWidth - 1);
uint nSubbandCount = (nSampleCount >> m_mioih.SubbandDegree);
uint nChannelCount = (uint)m_mioih.ChannelCount;
uint nAllSampleCount = nSampleCount * nChannelCount;
uint nAllSubbandCount = nSubbandCount * nChannelCount;
if (nSampleCount > m_nBufLength)
{
m_ptrBuffer2 = new int[nAllSampleCount];
m_ptrBuffer3 = new sbyte[nAllSampleCount * sizeof(short)];
m_ptrDivisionTable = new byte[nAllSubbandCount];
m_ptrWeightCode = new int[nAllSubbandCount * 5];
m_ptrCoefficient = new int[nAllSubbandCount * 5];
m_nBufLength = nSampleCount;
}
if (context.GetABit() != 0)
{
return false;
}
int[] pLastDivision = new int [nChannelCount];
m_ptrNextDivision = 0; // within m_ptrDivisionTable;
m_ptrNextWeight = 0; // within m_ptrWeightCode;
m_ptrNextCoefficient = 0; // within m_ptrCoefficient;
for (i = 0; i < nChannelCount; i++)
{
pLastDivision[i] = -1;
}
for (i = 0; i < nSubbandCount; i++)
{
for (j = 0; j < nChannelCount; j++)
{
int nDivisionCode = (int)context.GetNBits(2);
m_ptrDivisionTable[m_ptrNextDivision++] = (byte)nDivisionCode;
if (nDivisionCode != pLastDivision[j])
{
if (i != 0)
{
m_ptrWeightCode[m_ptrNextWeight++] = (int)context.GetNBits (32);
m_ptrCoefficient[m_ptrNextCoefficient++] = (int)context.GetNBits (16);
}
pLastDivision[j] = nDivisionCode;
}
uint nDivisionCount = 1u << nDivisionCode;
for (k = 0; k < nDivisionCount; k ++)
{
m_ptrWeightCode[m_ptrNextWeight++] = (int)context.GetNBits (32);
m_ptrCoefficient[m_ptrNextCoefficient++] = (int)context.GetNBits (16);
}
}
}
if (nSubbandCount > 0)
{
for (i = 0; i < nChannelCount; i++)
{
m_ptrWeightCode[m_ptrNextWeight++] = (int)context.GetNBits (32);
m_ptrCoefficient[m_ptrNextCoefficient++] = (int)context.GetNBits (16);
}
}
if (context.GetABit() != 0)
{
return false;
}
if (0 != (datahdr.Flags & MIO_LEAD_BLOCK))
{
if (m_mioih.Architecture != EriCode.Nemesis)
{
(context as HuffmanDecodeContext).PrepareToDecodeERINACode();
}
else
{
throw new NotImplementedException ("Nemesis encoding not implemented");
// context.PrepareToDecodeERISACode();
}
}
else if (m_mioih.Architecture == EriCode.Nemesis)
{
throw new NotImplementedException ("Nemesis encoding not implemented");
// context.InitializeERISACode();
}
if (m_mioih.Architecture != EriCode.Nemesis)
{
if (context.DecodeBytes (m_ptrBuffer3, nAllSampleCount * 2 ) < nAllSampleCount * 2)
{
return false;
}
int ptrHBuf = 0; // within m_ptrBuffer3;
int ptrLBuf = (int)nAllSampleCount; // within m_ptrBuffer3
for (i = 0; i < nDegreeWidth; i++)
{
int ptrQuantumized = (int)i; // within (PINT) m_ptrBuffer2
for (j = 0; j < nAllSubbandCount; j++)
{
int nLow = m_ptrBuffer3[ptrLBuf++];
int nHigh = m_ptrBuffer3[ptrHBuf++] ^ (nLow >> 8);
m_ptrBuffer2[ptrQuantumized] = (nLow & 0xFF) | (nHigh << 8);
ptrQuantumized += (int)nDegreeWidth;
}
}
}
else
{
throw new NotImplementedException ("Nemesis encoding not implemented");
/*
if (context.DecodeERISACodeWords (m_ptrBuffer3, nAllSampleCount) < nAllSampleCount)
{
return false;
}
for (i = 0; i < nAllSampleCount; i++)
{
((PINT)m_ptrBuffer2)[i] = ((SWORD*)m_ptrBuffer3)[i];
}
*/
}
uint nSamples;
uint[] pRestSamples = new uint [nChannelCount];
int[] ptrDstBuf = new int [nChannelCount]; // indices within ptrWaveBuf
m_ptrNextDivision = 0; // within m_ptrDivisionTable;
m_ptrNextWeight = 0; // within m_ptrWeightCode;
m_ptrNextCoefficient = 0; // within m_ptrCoefficient;
m_ptrNextSource = 0; // within (PINT) m_ptrBuffer2;
for (i = 0; i < nChannelCount; i++)
{
pLastDivision[i] = -1;
pRestSamples[i] = datahdr.SampleCount;
ptrDstBuf[i] = wave_pos + (int)i*sizeof(short);
}
int nCurrentDivision = -1;
for (i = 0; i < nSubbandCount; i++)
{
for (j = 0; j < nChannelCount; j++)
{
int nDivisionCode = m_ptrDivisionTable[m_ptrNextDivision++];
int nDivisionCount = 1 << nDivisionCode;
int nChannelStep = (int)(nDegreeWidth * m_mioih.LappedDegree * j);
m_ptrLastDCTBuf = nChannelStep; // within m_ptrLastDCT
bool fLeadBlock = false;
if (pLastDivision[j] != nDivisionCode)
{
if (i != 0)
{
if (nCurrentDivision != pLastDivision[j])
{
InitializeWithDegree (m_mioih.SubbandDegree - pLastDivision[j]);
nCurrentDivision = pLastDivision[j];
}
nSamples = pRestSamples[j];
if (nSamples > m_nDegreeNum)
{
nSamples = (uint)m_nDegreeNum;
}
DecodePostBlock (ptrWaveBuf, ptrDstBuf[j], nSamples);
pRestSamples[j] -= nSamples;
ptrDstBuf[j] += (int)(nSamples * nChannelCount * sizeof(short));
}
pLastDivision[j] = (int)nDivisionCode;
fLeadBlock = true;
}
if (nCurrentDivision != nDivisionCode)
{
InitializeWithDegree (m_mioih.SubbandDegree - nDivisionCode);
nCurrentDivision = nDivisionCode;
}
for (k = 0; k < nDivisionCount; k++)
{
if (fLeadBlock)
{
DecodeLeadBlock();
fLeadBlock = false;
}
else
{
nSamples = pRestSamples[j];
if (nSamples > m_nDegreeNum)
{
nSamples = (uint)m_nDegreeNum;
}
DecodeInternalBlock (ptrWaveBuf, ptrDstBuf[j], nSamples);
pRestSamples[j] -= nSamples;
ptrDstBuf[j] += (int)(nSamples * nChannelCount * sizeof(short));
}
}
}
}
if (nSubbandCount > 0)
{
for (i = 0; i < nChannelCount; i ++)
{
int nChannelStep = (int)(nDegreeWidth * m_mioih.LappedDegree * i);
m_ptrLastDCTBuf = nChannelStep; // within m_ptrLastDCT
if (nCurrentDivision != pLastDivision[i])
{
InitializeWithDegree (m_mioih.SubbandDegree - pLastDivision[i]);
nCurrentDivision = pLastDivision[i];
}
nSamples = pRestSamples[i];
if (nSamples > m_nDegreeNum)
{
nSamples = (uint)m_nDegreeNum;
}
DecodePostBlock (ptrWaveBuf, ptrDstBuf[i], nSamples);
pRestSamples[i] -= nSamples;
ptrDstBuf[i] += (int)(nSamples * nChannelCount * sizeof(short));
}
}
return true;
}
void DecodeInternalBlock (byte[] ptrDst, int iDst, uint nSamples)
{
int nWeightCode = m_ptrWeightCode[m_ptrNextWeight++];
int nCoefficient = m_ptrCoefficient[m_ptrNextCoefficient++];
IQuantumize (m_ptrMatrixBuf, 0, m_ptrBuffer2, m_ptrNextSource, m_nDegreeNum, nWeightCode, nCoefficient);
m_ptrNextSource += (int)m_nDegreeNum;
eriOddGivensInverseMatrix (m_ptrMatrixBuf, 0, m_pRevolveParam, m_nSubbandDegree);
eriFastIPLOT (m_ptrMatrixBuf, 0, m_nSubbandDegree);
eriFastILOT (m_ptrWorkBuf, m_ptrLastDCT, m_ptrLastDCTBuf, m_ptrMatrixBuf, 0, m_nSubbandDegree);
Array.Copy (m_ptrMatrixBuf, 0, m_ptrLastDCT, m_ptrLastDCTBuf, m_nDegreeNum);
Array.Copy (m_ptrWorkBuf, 0, m_ptrMatrixBuf, 0, m_nDegreeNum);
eriFastIDCT (m_ptrInternalBuf, m_ptrMatrixBuf, 0, 1, m_ptrWorkBuf, m_nSubbandDegree);
if (nSamples != 0)
{
eriRoundR32ToWordArray (ptrDst, iDst, m_mioih.ChannelCount, m_ptrInternalBuf, (int)nSamples);
}
}
void DecodeLeadBlock ()
{
int nWeightCode = m_ptrWeightCode[m_ptrNextWeight++];
int nCoefficient = m_ptrCoefficient[m_ptrNextCoefficient++];
uint i;
uint nHalfDegree = (uint)m_nDegreeNum / 2;
for (i = 0; i < nHalfDegree; i++)
{
m_ptrBuffer1[i * 2] = 0;
m_ptrBuffer1[i * 2 + 1] = m_ptrBuffer2[m_ptrNextSource++];
}
IQuantumize (m_ptrLastDCT, m_ptrLastDCTBuf, m_ptrBuffer1, 0, m_nDegreeNum, nWeightCode, nCoefficient);
eriOddGivensInverseMatrix (m_ptrLastDCT, m_ptrLastDCTBuf, m_pRevolveParam, m_nSubbandDegree);
for (i = 0; i < m_nDegreeNum; i += 2)
{
m_ptrLastDCT[m_ptrLastDCTBuf + i] = m_ptrLastDCT[m_ptrLastDCTBuf + i + 1];
}
eriFastIPLOT (m_ptrLastDCT, m_ptrLastDCTBuf, m_nSubbandDegree);
}
void DecodePostBlock (byte[] ptrDst, int iDst, uint nSamples)
{
int nWeightCode = m_ptrWeightCode[m_ptrNextWeight++];
int nCoefficient = m_ptrCoefficient[m_ptrNextCoefficient++];
uint i;
uint nHalfDegree = (uint)m_nDegreeNum / 2;
for (i = 0; i < nHalfDegree; i++)
{
m_ptrBuffer1[i * 2] = 0;
m_ptrBuffer1[i * 2 + 1] = m_ptrBuffer2[m_ptrNextSource++];
}
IQuantumize (m_ptrMatrixBuf, 0, m_ptrBuffer1, 0, m_nDegreeNum, nWeightCode, nCoefficient);
eriOddGivensInverseMatrix (m_ptrMatrixBuf, 0, m_pRevolveParam, m_nSubbandDegree);
for (i = 0; i < m_nDegreeNum; i += 2)
{
m_ptrMatrixBuf[i] = - m_ptrMatrixBuf[i + 1];
}
eriFastIPLOT (m_ptrMatrixBuf, 0, m_nSubbandDegree);
eriFastILOT (m_ptrWorkBuf, m_ptrLastDCT, m_ptrLastDCTBuf, m_ptrMatrixBuf, 0, m_nSubbandDegree);
Array.Copy (m_ptrWorkBuf, 0, m_ptrMatrixBuf, 0, m_nDegreeNum);
eriFastIDCT (m_ptrInternalBuf, m_ptrMatrixBuf, 0, 1, m_ptrWorkBuf, m_nSubbandDegree);
if (nSamples != 0)
{
eriRoundR32ToWordArray (ptrDst, iDst, m_mioih.ChannelCount, m_ptrInternalBuf, (int)nSamples);
}
}
bool DecodeSoundDCT_MSS (ERISADecodeContext context, MioDataHeader datahdr, byte[] ptrWaveBuf, int wave_pos)
{
uint nDegreeWidth = 1u << m_mioih.SubbandDegree;
uint nSampleCount = (datahdr.SampleCount + nDegreeWidth - 1) & ~(nDegreeWidth - 1);
uint nSubbandCount = (nSampleCount >> m_mioih.SubbandDegree);
uint nChannelCount = (uint)m_mioih.ChannelCount;
uint nAllSampleCount = nSampleCount * nChannelCount;
uint nAllSubbandCount = nSubbandCount;
if (nSampleCount > m_nBufLength)
{
m_ptrBuffer2 = new int[nAllSampleCount];
m_ptrBuffer3 = new sbyte[nAllSampleCount * sizeof(short)];
m_ptrDivisionTable = new byte[nAllSubbandCount];
m_ptrRevolveCode = new byte[nAllSubbandCount * 10];
m_ptrWeightCode = new int[nAllSubbandCount * 10];
m_ptrCoefficient = new int[nAllSubbandCount * 10];
m_nBufLength = nSampleCount;
}
if (context.GetABit() != 0)
{
return false;
}
int nLastDivision = -1;
m_ptrNextDivision = 0; // within m_ptrDivisionTable;
m_ptrNextRevCode = 0; // within m_ptrRevolveCode;
m_ptrNextWeight = 0; // within m_ptrWeightCode;
m_ptrNextCoefficient = 0; // within m_ptrCoefficient;
uint i, j, k;
for (i = 0; i < nSubbandCount; i ++)
{
int nDivisionCode = (int)context.GetNBits (2);
m_ptrDivisionTable[m_ptrNextDivision++] = (byte)nDivisionCode;
bool fLeadBlock = false;
if (nDivisionCode != nLastDivision)
{
if (i != 0)
{
m_ptrRevolveCode[m_ptrNextRevCode++] = (byte)context.GetNBits (2);
m_ptrWeightCode[m_ptrNextWeight++] = (int)context.GetNBits (32);
m_ptrCoefficient[m_ptrNextCoefficient++] = (int)context.GetNBits (16);
}
fLeadBlock = true;
nLastDivision = nDivisionCode;
}
uint nDivisionCount = 1u << nDivisionCode;
for (k = 0; k < nDivisionCount; k++)
{
if (fLeadBlock)
{
m_ptrRevolveCode[m_ptrNextRevCode++] = (byte)context.GetNBits (2);
fLeadBlock = false;
}
else
{
m_ptrRevolveCode[m_ptrNextRevCode++] = (byte)context.GetNBits (4);
}
m_ptrWeightCode[m_ptrNextWeight++] = (int)context.GetNBits (32);
m_ptrCoefficient[m_ptrNextCoefficient++] = (int)context.GetNBits (16);
}
}
if (nSubbandCount > 0)
{
m_ptrRevolveCode[m_ptrNextRevCode++] = (byte)context.GetNBits (2);
m_ptrWeightCode[m_ptrNextWeight++] = (int)context.GetNBits (32);
m_ptrCoefficient[m_ptrNextCoefficient++] = (int)context.GetNBits (16);
}
if (context.GetABit() != 0)
{
return false;
}
if (0 != (datahdr.Flags & MIO_LEAD_BLOCK))
{
if (m_mioih.Architecture != EriCode.Nemesis)
{
(context as HuffmanDecodeContext).PrepareToDecodeERINACode();
}
else
{
throw new NotImplementedException ("Nemesis encoding not implemented");
// context.PrepareToDecodeERISACode( );
}
}
else if (m_mioih.Architecture == EriCode.Nemesis)
{
throw new NotImplementedException ("Nemesis encoding not implemented");
// context.InitializeERISACode( );
}
if (m_mioih.Architecture != EriCode.Nemesis)
{
if (context.DecodeBytes (m_ptrBuffer3, nAllSampleCount * 2) < nAllSampleCount * 2)
{
return false;
}
int ptrHBuf = 0; // within m_ptrBuffer3;
int ptrLBuf = (int)nAllSampleCount; // within m_ptrBuffer3
for (i = 0; i < nDegreeWidth * 2; i++)
{
int ptrQuantumized = (int)i; // within (PINT) m_ptrBuffer2
for (j = 0; j < nAllSubbandCount; j++)
{
int nLow = m_ptrBuffer3[ptrLBuf++];
int nHigh = m_ptrBuffer3[ptrHBuf++] ^ (nLow >> 8);
m_ptrBuffer2[ptrQuantumized] = (nLow & 0xFF) | (nHigh << 8);
ptrQuantumized += (int)nDegreeWidth * 2;
}
}
}
else
{
throw new NotImplementedException ("Nemesis encoding not implemented");
/*
if ( context.DecodeERISACodeWords
( (SWORD*) m_ptrBuffer3, nAllSampleCount ) < nAllSampleCount )
{
return false;
}
for ( i = 0; i < nAllSampleCount; i ++ )
{
((PINT)m_ptrBuffer2)[i] = ((SWORD*)m_ptrBuffer3)[i];
}
*/
}
uint nSamples;
uint nRestSamples = datahdr.SampleCount;
// int ptrDstBuf = wave_pos; // within (SWORD*) ptrWaveBuf;
nLastDivision = -1;
m_ptrNextDivision = 0; // m_ptrDivisionTable;
m_ptrNextRevCode = 0; // m_ptrRevolveCode;
m_ptrNextWeight = 0; // m_ptrWeightCode;
m_ptrNextCoefficient = 0; // m_ptrCoefficient;
m_ptrNextSource = 0; // (PINT) m_ptrBuffer2;
for (i = 0; i < nSubbandCount; i++)
{
int nDivisionCode = m_ptrDivisionTable[m_ptrNextDivision++];
uint nDivisionCount = 1u << nDivisionCode;
bool fLeadBlock = false;
if (nLastDivision != nDivisionCode)
{
if (i != 0)
{
nSamples = Math.Min (nRestSamples, (uint)m_nDegreeNum);
DecodePostBlock_MSS (ptrWaveBuf, wave_pos, nSamples);
nRestSamples -= nSamples;
wave_pos += (int)(nSamples * nChannelCount * sizeof(short));
}
InitializeWithDegree (m_mioih.SubbandDegree - nDivisionCode);
nLastDivision = nDivisionCode;
fLeadBlock = true;
}
for (k = 0; k < nDivisionCount; k++)
{
if (fLeadBlock)
{
DecodeLeadBlock_MSS();
fLeadBlock = false;
}
else
{
nSamples = nRestSamples;
if (nSamples > m_nDegreeNum)
{
nSamples = (uint)m_nDegreeNum;
}
DecodeInternalBlock_MSS (ptrWaveBuf, wave_pos, nSamples);
nRestSamples -= nSamples;
wave_pos += (int)(nSamples * nChannelCount * sizeof(short));
}
}
}
if (nSubbandCount > 0)
{
nSamples = nRestSamples;
if (nSamples > m_nDegreeNum)
{
nSamples = (uint)m_nDegreeNum;
}
DecodePostBlock_MSS (ptrWaveBuf, wave_pos, nSamples);
nRestSamples -= nSamples;
wave_pos += (int)(nSamples * nChannelCount) * sizeof(short);
}
return true;
}
void DecodeLeadBlock_MSS ()
{
uint i, j;
uint nHalfDegree = (uint)m_nDegreeNum / 2;
int nWeightCode = m_ptrWeightCode[m_ptrNextWeight++];
int nCoefficient = m_ptrCoefficient[m_ptrNextCoefficient++];
int ptrLapBuf = 0; // within m_ptrLastDCT;
for (i = 0; i < 2; i++)
{
int ptrSrcBuf = 0; // within (PINT) m_ptrBuffer1;
for (j = 0; j < nHalfDegree; j++)
{
m_ptrBuffer1[ptrSrcBuf + j * 2] = 0;
m_ptrBuffer1[ptrSrcBuf + j * 2 + 1] = m_ptrBuffer2[m_ptrNextSource++];
}
IQuantumize (m_ptrLastDCT, ptrLapBuf, m_ptrBuffer1, ptrSrcBuf, m_nDegreeNum, nWeightCode, nCoefficient);
ptrLapBuf += (int)m_nDegreeNum;
}
int nRevCode = m_ptrRevolveCode[m_ptrNextRevCode++];
int ptrLapBuf1 = 0; // m_ptrLastDCT;
int ptrLapBuf2 = (int)m_nDegreeNum; // m_ptrLastDCT
float rSin = (float)Math.Sin (nRevCode * Math.PI / 8);
float rCos = (float)Math.Cos (nRevCode * Math.PI / 8);
eriRevolve2x2 (m_ptrLastDCT, ptrLapBuf1, m_ptrLastDCT, ptrLapBuf2, rSin, rCos, 1, m_nDegreeNum);
ptrLapBuf = 0; //m_ptrLastDCT;
for (i = 0; i < 2; i++)
{
eriOddGivensInverseMatrix (m_ptrLastDCT, ptrLapBuf, m_pRevolveParam, m_nSubbandDegree);
for (j = 0; j < m_nDegreeNum; j += 2)
{
m_ptrLastDCT[ptrLapBuf + j] = m_ptrLastDCT[ptrLapBuf + j + 1];
}
eriFastIPLOT (m_ptrLastDCT, ptrLapBuf, m_nSubbandDegree);
ptrLapBuf += (int)m_nDegreeNum;
}
}
void DecodeInternalBlock_MSS (byte[] ptrDst, int iDst, uint nSamples)
{
int ptrSrcBuf = 0; // m_ptrMatrixBuf;
int ptrLapBuf = 0; // m_ptrLastDCT;
int nWeightCode = m_ptrWeightCode[m_ptrNextWeight++];
int nCoefficient = m_ptrCoefficient[m_ptrNextCoefficient++];
for (int i = 0; i < 2; i++)
{
IQuantumize (m_ptrMatrixBuf, ptrSrcBuf, m_ptrBuffer2, m_ptrNextSource, m_nDegreeNum, nWeightCode, nCoefficient);
m_ptrNextSource += m_nDegreeNum;
ptrSrcBuf += m_nDegreeNum;
}
int nRevCode = m_ptrRevolveCode[m_ptrNextRevCode++];
int nRevCode1 = (nRevCode >> 2) & 0x03;
int nRevCode2 = (nRevCode & 0x03);
int ptrSrcBuf1 = 0; // m_ptrMatrixBuf;
int ptrSrcBuf2 = m_nDegreeNum; // m_ptrMatrixBuf + m_nDegreeNum;
float rSin = (float) Math.Sin (nRevCode1 * Math.PI / 8);
float rCos = (float) Math.Cos (nRevCode1 * Math.PI / 8);
eriRevolve2x2 (m_ptrMatrixBuf, ptrSrcBuf1, m_ptrMatrixBuf, ptrSrcBuf2, rSin, rCos, 2, m_nDegreeNum / 2);
rSin = (float) Math.Sin (nRevCode2 * Math.PI / 8);
rCos = (float) Math.Cos (nRevCode2 * Math.PI / 8);
eriRevolve2x2 (m_ptrMatrixBuf, ptrSrcBuf1 + 1, m_ptrMatrixBuf, ptrSrcBuf2 + 1, rSin, rCos, 2, m_nDegreeNum / 2);
ptrSrcBuf = 0; // m_ptrMatrixBuf;
for (int i = 0; i < 2; i++)
{
eriOddGivensInverseMatrix (m_ptrMatrixBuf, ptrSrcBuf, m_pRevolveParam, m_nSubbandDegree);
eriFastIPLOT (m_ptrMatrixBuf, ptrSrcBuf, m_nSubbandDegree);
eriFastILOT (m_ptrWorkBuf, m_ptrLastDCT, ptrLapBuf, m_ptrMatrixBuf, ptrSrcBuf, m_nSubbandDegree);
Array.Copy (m_ptrMatrixBuf, ptrSrcBuf, m_ptrLastDCT, ptrLapBuf, m_nDegreeNum);
Array.Copy (m_ptrWorkBuf, 0, m_ptrMatrixBuf, ptrSrcBuf, m_nDegreeNum);
eriFastIDCT (m_ptrInternalBuf, m_ptrMatrixBuf, ptrSrcBuf, 1, m_ptrWorkBuf, m_nSubbandDegree);
if (nSamples != 0)
{
eriRoundR32ToWordArray (ptrDst, iDst + (int)i*2, 2, m_ptrInternalBuf, (int)nSamples);
}
ptrSrcBuf += m_nDegreeNum;
ptrLapBuf += m_nDegreeNum;
}
}
void DecodePostBlock_MSS (byte[] ptrDst, int iDst, uint nSamples)
{
int ptrLapBuf = 0; // m_ptrLastDCT;
int ptrSrcBuf = 0; // m_ptrMatrixBuf;
int i, j;
uint nHalfDegree = (uint)m_nDegreeNum / 2u;
int nWeightCode = m_ptrWeightCode[m_ptrNextWeight++];
int nCoefficient = m_ptrCoefficient[m_ptrNextCoefficient++];
for (i = 0; i < 2; i++)
{
for (j = 0; j < nHalfDegree; j++)
{
m_ptrBuffer1[j * 2] = 0;
m_ptrBuffer1[j * 2 + 1] = m_ptrBuffer2[m_ptrNextSource++];
}
IQuantumize (m_ptrMatrixBuf, ptrSrcBuf, m_ptrBuffer1, 0, m_nDegreeNum, nWeightCode, nCoefficient);
ptrSrcBuf += m_nDegreeNum;
}
float rSin, rCos;
int nRevCode = m_ptrRevolveCode[m_ptrNextRevCode++];
int ptrSrcBuf1 = 0; // m_ptrMatrixBuf;
int ptrSrcBuf2 = m_nDegreeNum; // m_ptrMatrixBuf + m_nDegreeNum;
rSin = (float) Math.Sin (nRevCode * Math.PI / 8);
rCos = (float) Math.Cos (nRevCode * Math.PI / 8);
eriRevolve2x2 (m_ptrMatrixBuf, ptrSrcBuf1, m_ptrMatrixBuf, ptrSrcBuf2, rSin, rCos, 1, m_nDegreeNum);
ptrSrcBuf = 0; // m_ptrMatrixBuf;
for (i = 0; i < 2; i ++)
{
eriOddGivensInverseMatrix (m_ptrMatrixBuf, ptrSrcBuf, m_pRevolveParam, m_nSubbandDegree);
for (j = 0; j < m_nDegreeNum; j += 2)
{
m_ptrMatrixBuf[ptrSrcBuf + j] = -m_ptrMatrixBuf[ptrSrcBuf + j + 1];
}
eriFastIPLOT (m_ptrMatrixBuf, ptrSrcBuf, m_nSubbandDegree);
eriFastILOT (m_ptrWorkBuf, m_ptrLastDCT, ptrLapBuf, m_ptrMatrixBuf, ptrSrcBuf, m_nSubbandDegree);
Array.Copy (m_ptrWorkBuf, 0, m_ptrMatrixBuf, ptrSrcBuf, m_nDegreeNum);
eriFastIDCT (m_ptrInternalBuf, m_ptrMatrixBuf, ptrSrcBuf, 1, m_ptrWorkBuf, m_nSubbandDegree);
if (nSamples != 0)
{
eriRoundR32ToWordArray (ptrDst, iDst + (int)i*2, 2, m_ptrInternalBuf, (int)nSamples);
}
ptrLapBuf += m_nDegreeNum;
ptrSrcBuf += m_nDegreeNum;
}
}
void IQuantumize (float[] ptrDestination, int dst, int[] ptrQuantumized, int qsrc, int nDegreeNum, int nWeightCode, int nCoefficient)
{
int i, j;
double rMatrixScale = Math.Sqrt (2.0 / nDegreeNum);
double rCoefficient = rMatrixScale * nCoefficient;
double[] rAvgRatio = new double[7];
for (i = 0; i < 6; i++)
{
rAvgRatio[i] = 1.0 / Math.Pow (2.0, (((nWeightCode >> (i * 5)) & 0x1F) - 15) * 0.5);
}
rAvgRatio[6] = 1.0;
for (i = 0; i < m_nFrequencyPoint[0]; i++)
{
m_ptrWeightTable[i] = (float) rAvgRatio[0];
}
for (j = 1; j < 7; j++)
{
double a = rAvgRatio[j - 1];
double k = (rAvgRatio[j] - a) / (m_nFrequencyPoint[j] - m_nFrequencyPoint[j - 1]);
while (i < m_nFrequencyPoint[j])
{
m_ptrWeightTable[i] = (float)(k * (i - m_nFrequencyPoint[j - 1]) + a);
i++;
}
}
while (i < nDegreeNum)
{
m_ptrWeightTable[i++] = (float)rAvgRatio[6];
}
float rOddWeight = (float)((((nWeightCode >> 30) & 0x03) + 0x02) / 2.0);
for (i = 15; i < nDegreeNum; i += 16)
{
m_ptrWeightTable[i] *= rOddWeight;
}
m_ptrWeightTable[nDegreeNum-1] = (float) nCoefficient;
for (i = 0; i < nDegreeNum; i++)
{
m_ptrWeightTable[i] = 1.0F / m_ptrWeightTable[i];
}
for (i = 0; i < nDegreeNum; i ++)
{
ptrDestination[dst + i] = (float) (rCoefficient * m_ptrWeightTable[i] * ptrQuantumized[qsrc+i]);
}
}
static readonly float ERI_rCosPI4 = (float)Math.Cos (Math.PI / 4);
static readonly float ERI_r2CosPI4 = 2 * ERI_rCosPI4;
static readonly float[] ERI_DCTofK2 = new float[2]; // = cos( (2*i+1) / 8 )
static readonly float[] ERI_DCTofK4 = new float[4]; // = cos( (2*i+1) / 16 )
static readonly float[] ERI_DCTofK8 = new float[8]; // = cos( (2*i+1) / 32 )
static readonly float[] ERI_DCTofK16 = new float[16]; // = cos( (2*i+1) / 64 )
static readonly float[] ERI_DCTofK32 = new float[32]; // = cos( (2*i+1) / 128 )
static readonly float[] ERI_DCTofK64 = new float[64]; // = cos( (2*i+1) / 256 )
static readonly float[] ERI_DCTofK128 = new float[128]; // = cos( (2*i+1) / 512 )
static readonly float[] ERI_DCTofK256 = new float[256]; // = cos( (2*i+1) / 1024 )
static readonly float[] ERI_DCTofK512 = new float[512]; // = cos( (2*i+1) / 2048 )
static readonly float[] ERI_DCTofK1024 = new float[1024]; // = cos( (2*i+1) / 4096 )
static readonly float[] ERI_DCTofK2048 = new float[2048]; // = cos( (2*i+1) / 8192 )
static readonly float[][] ERI_pMatrixDCTofK = new float[MAX_DCT_DEGREE][]
{
null,
ERI_DCTofK2,
ERI_DCTofK4,
ERI_DCTofK8,
ERI_DCTofK16,
ERI_DCTofK32,
ERI_DCTofK64,
ERI_DCTofK128,
ERI_DCTofK256,
ERI_DCTofK512,
ERI_DCTofK1024,
ERI_DCTofK2048
};
static void eriInitializeMatrix ()
{
for (int i = 1; i < MAX_DCT_DEGREE; i++)
{
int n = (1 << i);
float[] pDCTofK = ERI_pMatrixDCTofK[i];
double nr = Math.PI / (4.0 * n);
double dr = nr + nr;
double ir = nr;
for (int j = 0; j < n; j++)
{
pDCTofK[j] = (float)Math.Cos (ir);
ir += dr;
}
}
}
static void eriRoundR32ToWordArray (byte[] ptrDst, int dst, int nStep, float[] ptrSrc, int nCount)
{
nStep *= 2;
for (int i = 0; i < nCount; i++)
{
int nValue = eriRoundR32ToInt (ptrSrc[i]);
if (nValue <= -0x8000)
{
LittleEndian.Pack ((short)-0x8000, ptrDst, dst);
}
else if (nValue >= 0x7FFF)
{
LittleEndian.Pack ((short)0x7FFF, ptrDst, dst);
}
else
{
LittleEndian.Pack ((short)nValue, ptrDst, dst);
}
dst += nStep;
}
}
static int eriRoundR32ToInt (float r)
{
if (r >= 0.0)
return (int)Math.Floor (r + 0.5);
else
return (int)Math.Ceiling (r - 0.5);
}
static EriSinCos[] eriCreateRevolveParameter (int nDegreeDCT)
{
int nDegreeNum = 1 << nDegreeDCT;
int lc = 1;
for (int n = nDegreeNum / 2; n >= 8; n /= 8)
{
++lc;
}
EriSinCos[] ptrRevolve = new EriSinCos[lc*8];
double k = Math.PI / (nDegreeNum * 2);
int ptrNextRev = 0;
int nStep = 2;
do
{
for (int i = 0; i < 7; i++)
{
double ws = 1.0;
double a = 0.0;
for (int j = 0; j < i; j++)
{
a += nStep;
ws = ws * ptrRevolve[ptrNextRev+j].rSin + ptrRevolve[ptrNextRev+j].rCos * Math.Cos (a * k);
}
double r = Math.Atan2 (ws, Math.Cos ((a + nStep) * k));
ptrRevolve[ptrNextRev+i].rSin = (float)Math.Sin (r);
ptrRevolve[ptrNextRev+i].rCos = (float)Math.Cos (r);
}
ptrNextRev += 7;
nStep *= 8;
}
while (nStep < nDegreeNum);
return ptrRevolve;
}
static void eriOddGivensInverseMatrix (float[] ptrSrc, int src, EriSinCos[] ptrRevolve, int nDegreeDCT)
{
int nDegreeNum = 1 << nDegreeDCT;
int index = 1;
int nStep = 2;
int lc = (nDegreeNum / 2) / 8;
int resolve_idx = 0;
for (;;)
{
resolve_idx += 7;
index += nStep * 7;
nStep *= 8;
if (lc <= 8)
break;
lc /= 8;
}
int k = index + nStep * (lc - 2);
int j;
float r1, r2;
for (j = lc - 2; j >= 0; j--)
{
r1 = ptrSrc[src + k];
r2 = ptrSrc[src + k + nStep];
ptrSrc[src + k] = r1 * ptrRevolve[resolve_idx+j].rCos + r2 * ptrRevolve[resolve_idx+j].rSin;
ptrSrc[src + k + nStep] = r2 * ptrRevolve[resolve_idx+j].rCos - r1 * ptrRevolve[resolve_idx+j].rSin;
k -= nStep;
}
for (; lc <= (nDegreeNum / 2) / 8; lc *= 8)
{
resolve_idx -= 7;
nStep /= 8;
index -= nStep * 7;
for (int i = 0; i < lc; i++)
{
k = i * (nStep * 8) + index + nStep * 6;
for ( j = 6; j >= 0; j -- )
{
r1 = ptrSrc[src + k];
r2 = ptrSrc[src + k + nStep];
ptrSrc[src + k] =
r1 * ptrRevolve[resolve_idx+j].rCos + r2 * ptrRevolve[resolve_idx+j].rSin;
ptrSrc[src + k + nStep] =
r2 * ptrRevolve[resolve_idx+j].rCos - r1 * ptrRevolve[resolve_idx+j].rSin;
k -= nStep;
}
}
}
}
static void eriFastIPLOT (float[] ptrSrc, int src, int nDegreeDCT)
{
int nDegreeNum = 1 << nDegreeDCT;
for (int i = 0; i < nDegreeNum; i += 2)
{
float r1 = ptrSrc[src + i];
float r2 = ptrSrc[src + i + 1];
ptrSrc[src + i] = 0.5f * (r1 + r2);
ptrSrc[src + i + 1] = 0.5f * (r1 - r2);
}
}
static void eriFastILOT (float[] ptrDst, float[] ptrSrc1, int src1, float[] ptrSrc2, int src2, int nDegreeDCT)
{
int nDegreeNum = 1 << nDegreeDCT;
for (int i = 0; i < nDegreeNum; i += 2)
{
float r1 = ptrSrc1[src1 + i];
float r2 = ptrSrc2[src2 + i + 1];
ptrDst[i] = r1 + r2;
ptrDst[i + 1] = r1 - r2;
}
}
static void eriFastDCT (float[] ptrDst, int dst, int nDstInterval, float[] ptrSrc, int src, float[] ptrWorkBuf, int work, int nDegreeDCT)
{
Debug.Assert ((nDegreeDCT >= MIN_DCT_DEGREE) && (nDegreeDCT <= MAX_DCT_DEGREE));
if (nDegreeDCT == MIN_DCT_DEGREE)
{
float[] r32Buf = new float[4];
r32Buf[0] = ptrSrc[src] + ptrSrc[src+3];
r32Buf[2] = ptrSrc[src] - ptrSrc[src+3];
r32Buf[1] = ptrSrc[src+1] + ptrSrc[src+2];
r32Buf[3] = ptrSrc[src+1] - ptrSrc[src+2];
ptrDst[dst] = 0.5f * (r32Buf[0] + r32Buf[1]);
ptrDst[dst+nDstInterval * 2] = ERI_rCosPI4 * (r32Buf[0] - r32Buf[1]);
r32Buf[2] = ERI_DCTofK2[0] * r32Buf[2];
r32Buf[3] = ERI_DCTofK2[1] * r32Buf[3];
r32Buf[0] = r32Buf[2] + r32Buf[3];
r32Buf[1] = ERI_r2CosPI4 * (r32Buf[2] - r32Buf[3]);
r32Buf[1] -= r32Buf[0];
ptrDst[dst+nDstInterval] = r32Buf[0];
ptrDst[dst+nDstInterval * 3] = r32Buf[1];
}
else
{
uint i;
uint nDegreeNum = 1u << nDegreeDCT;
uint nHalfDegree = nDegreeNum >> 1;
for (i = 0; i < nHalfDegree; i++)
{
ptrWorkBuf[work+i] = ptrSrc[src+i] + ptrSrc[src + nDegreeNum - i - 1];
ptrWorkBuf[work+i + nHalfDegree] = ptrSrc[src+i] - ptrSrc[src + nDegreeNum - i - 1];
}
int nDstStep = nDstInterval << 1;
eriFastDCT (ptrDst, dst, nDstStep, ptrWorkBuf, work, ptrSrc, src, nDegreeDCT - 1);
float[] pDCTofK = ERI_pMatrixDCTofK[nDegreeDCT - 1];
src = (int)(work+nHalfDegree); // ptrSrc = ptrWorkBuf + nHalfDegree;
dst += nDstInterval; // ptrDst += nDstInterval;
for (i = 0; i < nHalfDegree; i++)
{
ptrWorkBuf[src + i] *= pDCTofK[i];
}
eriFastDCT (ptrDst, dst, nDstStep, ptrWorkBuf, src, ptrWorkBuf, work, nDegreeDCT - 1);
// eriFastDCT (ptrDst, nDstStep, ptrSrc, ptrWorkBuf, nDegreeDCT - 1);
int ptrNext = dst; // within ptrDst;
for (i = 0; i < nHalfDegree; i++)
{
ptrDst[ptrNext] += ptrDst[ptrNext]; // *ptrNext += *ptrNext;
ptrNext += nDstStep;
}
ptrNext = dst;
for (i = 1; i < nHalfDegree; i ++)
{
ptrDst[ptrNext + nDstStep] -= ptrDst[ptrNext];
ptrNext += nDstStep;
}
}
}
static void eriFastIDCT (float[] ptrDst, float[] srcBuf, int ptrSrc, int nSrcInterval, float[] ptrWorkBuf, int nDegreeDCT)
{
Debug.Assert ((nDegreeDCT >= MIN_DCT_DEGREE) && (nDegreeDCT <= MAX_DCT_DEGREE));
if (nDegreeDCT == MIN_DCT_DEGREE)
{
float[] r32Buf1 = new float[2];
float[] r32Buf2 = new float[4];
r32Buf1[0] = srcBuf[ptrSrc];
r32Buf1[1] = ERI_rCosPI4 * srcBuf[ptrSrc + nSrcInterval * 2];
r32Buf2[0] = r32Buf1[0] + r32Buf1[1];
r32Buf2[1] = r32Buf1[0] - r32Buf1[1];
r32Buf1[0] = ERI_DCTofK2[0] * srcBuf[ptrSrc + nSrcInterval];
r32Buf1[1] = ERI_DCTofK2[1] * srcBuf[ptrSrc + nSrcInterval * 3];
r32Buf2[2] = r32Buf1[0] + r32Buf1[1];
r32Buf2[3] = ERI_r2CosPI4 * (r32Buf1[0] - r32Buf1[1]);
r32Buf2[3] -= r32Buf2[2];
ptrDst[0] = r32Buf2[0] + r32Buf2[2];
ptrDst[3] = r32Buf2[0] - r32Buf2[2];
ptrDst[1] = r32Buf2[1] + r32Buf2[3];
ptrDst[2] = r32Buf2[1] - r32Buf2[3];
}
else
{
uint nDegreeNum = 1u << nDegreeDCT;
uint nHalfDegree = nDegreeNum >> 1;
int nSrcStep = nSrcInterval << 1;
eriFastIDCT (ptrDst, srcBuf, ptrSrc, nSrcStep, ptrWorkBuf, nDegreeDCT - 1);
float[] pDCTofK = ERI_pMatrixDCTofK[nDegreeDCT - 1];
int pOddDst = (int)nHalfDegree; // within ptrDst
int ptrNext = ptrSrc + nSrcInterval; // within srcBuf
uint i;
for (i = 0; i < nHalfDegree; i++)
{
ptrWorkBuf[i] = srcBuf[ptrNext] * pDCTofK[i];
ptrNext += nSrcStep;
}
eriFastDCT (ptrDst, pOddDst, 1, ptrWorkBuf, 0, ptrWorkBuf, (int)nHalfDegree, nDegreeDCT - 1);
// eriFastDCT(pOddDst, 1, ptrWorkBuf, (ptrWorkBuf + nHalfDegree), nDegreeDCT - 1);
for (i = 0; i < nHalfDegree; i ++)
{
ptrDst[pOddDst + i] += ptrDst[pOddDst + i];
}
for (i = 1; i < nHalfDegree; i++)
{
ptrDst[pOddDst + i] -= ptrDst[pOddDst + i - 1];
}
float[] r32Buf = new float[4];
uint nQuadDegree = nHalfDegree >> 1;
for (i = 0; i < nQuadDegree; i++)
{
r32Buf[0] = ptrDst[i] + ptrDst[nHalfDegree + i];
r32Buf[3] = ptrDst[i] - ptrDst[nHalfDegree + i];
r32Buf[1] = ptrDst[nHalfDegree - 1 - i] + ptrDst[nDegreeNum - 1 - i];
r32Buf[2] = ptrDst[nHalfDegree - 1 - i] - ptrDst[nDegreeNum - 1 - i];
ptrDst[i] = r32Buf[0];
ptrDst[nHalfDegree - 1 - i] = r32Buf[1];
ptrDst[nHalfDegree + i] = r32Buf[2];
ptrDst[nDegreeNum - 1 - i] = r32Buf[3];
}
}
}
void eriRevolve2x2 (float[] buf1, int ptrBuf1, float[] buf2, int ptrBuf2, float rSin, float rCos, int nStep, int nCount)
{
for (int i = 0; i < nCount; i++)
{
float r1 = buf1[ptrBuf1];
float r2 = buf2[ptrBuf2];
buf1[ptrBuf1] = r1 * rCos - r2 * rSin;
buf2[ptrBuf2] = r1 * rSin + r2 * rCos;
ptrBuf1 += nStep;
ptrBuf2 += nStep;
}
}
}
}