QuantRDOQ.cpp

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/** \file     QuantRDOQ.cpp
    \brief    transform and quantization class
*/

#include "QuantRDOQ.h"

#include "UnitTools.h"
#include "ContextModelling.h"
#include "CodingStructure.h"
#include "CrossCompPrediction.h"

#include "dtrace_next.h"
#include "dtrace_buffer.h"

#include <stdlib.h>
#include <limits>
#include <memory.h>


struct coeffGroupRDStats
{
  int    iNNZbeforePos0;
  double d64CodedLevelandDist; // distortion and level cost only
  double d64UncodedDist;    // all zero coded block distortion
  double d64SigCost;
  double d64SigCost_0;
};


//! \ingroup CommonLib
//! \{

// ====================================================================================================================
// Constants
// ====================================================================================================================


// ====================================================================================================================
// Static functions
// ====================================================================================================================

// ====================================================================================================================
// QuantRDOQ class member functions
// ====================================================================================================================


QuantRDOQ::QuantRDOQ( const Quant* other ) : Quant( other )
{

  const QuantRDOQ *rdoq = dynamic_cast<const QuantRDOQ*>( other );
  CHECK( other && !rdoq, "The RDOQ cast must be successfull!" );
#if HEVC_USE_SCALING_LISTS
  xInitScalingList( rdoq );
#endif
}

QuantRDOQ::~QuantRDOQ()
{
#if HEVC_USE_SCALING_LISTS
  xDestroyScalingList();
#endif
}




/** Get the best level in RD sense
 *
 * \returns best quantized transform level for given scan position
 *
 * This method calculates the best quantized transform level for a given scan position.
 */
inline uint32_t QuantRDOQ::xGetCodedLevel( double&            rd64CodedCost,
                                       double&            rd64CodedCost0,
                                       double&            rd64CodedCostSig,
                                       Intermediate_Int   lLevelDouble,
                                       uint32_t               uiMaxAbsLevel,
                                       const BinFracBits* fracBitsSig,
                                       const BinFracBits& fracBitsPar,
                                       const BinFracBits& fracBitsGt1,
                                       const BinFracBits& fracBitsGt2,
                                       const int          remGt2Bins,
                                       const int          remRegBins,
                                       unsigned           goRiceZero,
                                       uint16_t             ui16AbsGoRice,
                                       int                iQBits,
                                       double             errorScale,
                                       bool               bLast,
                                       bool               useLimitedPrefixLength,
                                       const int          maxLog2TrDynamicRange
                                     ) const
{
  double dCurrCostSig   = 0;
  uint32_t   uiBestAbsLevel = 0;

  if( !bLast && uiMaxAbsLevel < 3 )
  {
    rd64CodedCostSig    = xGetRateSigCoef( *fracBitsSig, 0 );
    rd64CodedCost       = rd64CodedCost0 + rd64CodedCostSig;
    if( uiMaxAbsLevel == 0 )
    {
      return uiBestAbsLevel;
    }
  }
  else
  {
    rd64CodedCost       = MAX_DOUBLE;
  }

  if( !bLast )
  {
    dCurrCostSig        = xGetRateSigCoef( *fracBitsSig, 1 );
  }

  uint32_t uiMinAbsLevel    = ( uiMaxAbsLevel > 1 ? uiMaxAbsLevel - 1 : 1 );
  for( int uiAbsLevel  = uiMaxAbsLevel; uiAbsLevel >= uiMinAbsLevel ; uiAbsLevel-- )
  {
    double dErr         = double( lLevelDouble  - ( Intermediate_Int(uiAbsLevel) << iQBits ) );

    double dCurrCost    = dErr * dErr * errorScale + xGetICost( xGetICRate( uiAbsLevel, fracBitsPar, fracBitsGt1, fracBitsGt2, remGt2Bins, remRegBins, goRiceZero, ui16AbsGoRice, true, maxLog2TrDynamicRange ) );
    dCurrCost          += dCurrCostSig;

    if( dCurrCost < rd64CodedCost )
    {
      uiBestAbsLevel    = uiAbsLevel;
      rd64CodedCost     = dCurrCost;
      rd64CodedCostSig  = dCurrCostSig;
    }
  }

  return uiBestAbsLevel;
}

/** Calculates the cost for specific absolute transform level
 * \param uiAbsLevel scaled quantized level
 * \param ui16CtxNumOne current ctxInc for coeff_abs_level_greater1 (1st bin of coeff_abs_level_minus1 in AVC)
 * \param ui16CtxNumAbs current ctxInc for coeff_abs_level_greater2 (remaining bins of coeff_abs_level_minus1 in AVC)
 * \param ui16AbsGoRice Rice parameter for coeff_abs_level_minus3
 * \param c1Idx
 * \param c2Idx
 * \param useLimitedPrefixLength
 * \param maxLog2TrDynamicRange
 * \returns cost of given absolute transform level
 */
inline int QuantRDOQ::xGetICRate( const uint32_t         uiAbsLevel,
                                  const BinFracBits& fracBitsPar,
                                  const BinFracBits& fracBitsGt1,
                                  const BinFracBits& fracBitsGt2,
                                  const int          remGt2Bins,
                                  const int          remRegBins,
                                  unsigned           goRiceZero,
                                  const uint16_t       ui16AbsGoRice,
                                  const bool         useLimitedPrefixLength,
                                  const int          maxLog2TrDynamicRange  ) const
{
  if( remRegBins < 4 )
  {
    int       iRate   = int( xGetIEPRate() ); // cost of sign bit
    uint32_t  symbol  = ( uiAbsLevel == 0 ? goRiceZero : uiAbsLevel <= goRiceZero ? uiAbsLevel-1 : uiAbsLevel );
    uint32_t  length;
    const int threshold = COEF_REMAIN_BIN_REDUCTION;
    if( symbol < ( threshold << ui16AbsGoRice ) )
    {
      length = symbol >> ui16AbsGoRice;
      iRate += ( length + 1 + ui16AbsGoRice ) << SCALE_BITS;
    }
    else if( useLimitedPrefixLength )
    {
      const uint32_t maximumPrefixLength = ( 32 - ( COEF_REMAIN_BIN_REDUCTION + maxLog2TrDynamicRange ) );

      uint32_t prefixLength = 0;
      uint32_t suffix = ( symbol >> ui16AbsGoRice ) - COEF_REMAIN_BIN_REDUCTION;

      while( ( prefixLength < maximumPrefixLength ) && ( suffix > ( ( 2 << prefixLength ) - 2 ) ) )
      {
        prefixLength++;
      }

      const uint32_t suffixLength = ( prefixLength == maximumPrefixLength ) ? ( maxLog2TrDynamicRange - ui16AbsGoRice ) : ( prefixLength + 1/*separator*/ );

      iRate += ( COEF_REMAIN_BIN_REDUCTION + prefixLength + suffixLength + ui16AbsGoRice ) << SCALE_BITS;
    }
    else
    {
      length = ui16AbsGoRice;
      symbol = symbol - ( threshold << ui16AbsGoRice );
      while( symbol >= ( 1 << length ) )
      {
        symbol -= ( 1 << ( length++ ) );
      }
      iRate += ( threshold + length + 1 - ui16AbsGoRice + length ) << SCALE_BITS;
    }
    return iRate;
  }

  int iRate = int( xGetIEPRate() ); // cost of sign bit
  const uint32_t cthres = 4;
  if( uiAbsLevel >= cthres )
  {
    uint32_t symbol = ( uiAbsLevel - cthres ) >> 1;
    uint32_t length;
    const int threshold = COEF_REMAIN_BIN_REDUCTION;
    if( symbol < ( threshold << ui16AbsGoRice ) )
    {
      length = symbol >> ui16AbsGoRice;
      iRate += ( length + 1 + ui16AbsGoRice ) << SCALE_BITS;
    }
    else if( useLimitedPrefixLength )
    {
      const uint32_t maximumPrefixLength = ( 32 - ( COEF_REMAIN_BIN_REDUCTION + maxLog2TrDynamicRange ) );

      uint32_t prefixLength = 0;
      uint32_t suffix = ( symbol >> ui16AbsGoRice ) - COEF_REMAIN_BIN_REDUCTION;

      while( ( prefixLength < maximumPrefixLength ) && ( suffix > ( ( 2 << prefixLength ) - 2 ) ) )
      {
        prefixLength++;
      }

      const uint32_t suffixLength = ( prefixLength == maximumPrefixLength ) ? ( maxLog2TrDynamicRange - ui16AbsGoRice ) : ( prefixLength + 1/*separator*/ );

      iRate += ( COEF_REMAIN_BIN_REDUCTION + prefixLength + suffixLength + ui16AbsGoRice ) << SCALE_BITS;
    }
    else
    {
      length = ui16AbsGoRice;
      symbol = symbol - ( threshold << ui16AbsGoRice );
      while( symbol >= ( 1 << length ) )
      {
        symbol -= ( 1 << ( length++ ) );
      }
      iRate += ( threshold + length + 1 - ui16AbsGoRice + length ) << SCALE_BITS;
    }

    iRate += fracBitsGt1.intBits[1];
    iRate += fracBitsPar.intBits[( uiAbsLevel - 2 ) & 1];
    iRate += fracBitsGt2.intBits[1];
  }
  else if( uiAbsLevel == 1 )
  {
    iRate += fracBitsGt1.intBits[0];
  }
  else if( uiAbsLevel == 2 )
  {
    iRate += fracBitsGt1.intBits[1];
    iRate += fracBitsPar.intBits[0];
    iRate += fracBitsGt2.intBits[0];
  }
  else if( uiAbsLevel == 3 )
  {
    iRate += fracBitsGt1.intBits[1];
    iRate += fracBitsPar.intBits[1];
    iRate += fracBitsGt2.intBits[0];
  }
  else
  {
    iRate = 0;
  }
  return  iRate;
}

inline double QuantRDOQ::xGetRateSigCoeffGroup( const BinFracBits& fracBitsSigCG, unsigned uiSignificanceCoeffGroup ) const
{
  return xGetICost( fracBitsSigCG.intBits[uiSignificanceCoeffGroup] );
}

/** Calculates the cost of signaling the last significant coefficient in the block
 * \param uiPosX X coordinate of the last significant coefficient
 * \param uiPosY Y coordinate of the last significant coefficient
 * \param component colour component ID
 * \returns cost of last significant coefficient
 */
/*
 * \param uiWidth width of the transform unit (TU)
*/
inline double QuantRDOQ::xGetRateLast( const int* lastBitsX, const int* lastBitsY, unsigned PosX, unsigned PosY ) const
{
  uint32_t    CtxX  = g_uiGroupIdx[PosX];
  uint32_t    CtxY  = g_uiGroupIdx[PosY];
  double  Cost  = lastBitsX[ CtxX ] + lastBitsY[ CtxY ];
  if( CtxX > 3 )
  {
    Cost += xGetIEPRate() * ((CtxX-2)>>1);
  }
  if( CtxY > 3 )
  {
    Cost += xGetIEPRate() * ((CtxY-2)>>1);
  }
  return xGetICost( Cost );
}


inline double QuantRDOQ::xGetRateSigCoef( const BinFracBits& fracBitsSig, unsigned uiSignificance ) const
{
  return xGetICost( fracBitsSig.intBits[uiSignificance] );
}

/** Get the cost for a specific rate
 * \param dRate rate of a bit
 * \returns cost at the specific rate
 */
inline double QuantRDOQ::xGetICost        ( double                          dRate         ) const
{
  return m_dLambda * dRate;
}

/** Get the cost of an equal probable bit
 * \returns cost of equal probable bit
 */
inline double QuantRDOQ::xGetIEPRate      (                                               ) const
{
  return 32768;
}



#if HEVC_USE_SCALING_LISTS
/** set quantized matrix coefficient for encode
 * \param scalingList            quantized matrix address
 * \param format                 chroma format
 * \param maxLog2TrDynamicRange
 * \param bitDepths              reference to bit depth array for all channels
 */
void QuantRDOQ::setScalingList(ScalingList *scalingList, const int maxLog2TrDynamicRange[MAX_NUM_CHANNEL_TYPE], const BitDepths &bitDepths)
{
  Quant::setScalingList( scalingList, maxLog2TrDynamicRange, bitDepths );

  const int minimumQp = 0;
  const int maximumQp = SCALING_LIST_REM_NUM;

  for(uint32_t size = 0; size < SCALING_LIST_SIZE_NUM; size++)
  {
    for(uint32_t list = 0; list < SCALING_LIST_NUM; list++)
    {
      for(int qp = minimumQp; qp < maximumQp; qp++)
      {
//         xSetScalingListEnc(scalingList,list,size,qp);
//         xSetScalingListDec(*scalingList,list,size,qp);
        xSetErrScaleCoeff(list,size, size,qp,maxLog2TrDynamicRange, bitDepths);
      }
    }
  }
}



#if HM_QTBT_AS_IN_JEM_QUANT
#endif
#else

#if JVET_N0246_MODIFIED_QUANTSCALES
double QuantRDOQ::xGetErrScaleCoeff( const bool needsSqrt2, SizeType width, SizeType height, int qp, const int maxLog2TrDynamicRange, const int channelBitDepth )
{
  const int iTransformShift = getTransformShift(channelBitDepth, Size(width, height), maxLog2TrDynamicRange);
  double    dErrScale       = (double)( 1 << SCALE_BITS );                                // Compensate for scaling of bitcount in Lagrange cost function
  double    dTransShift     = (double)iTransformShift + ( needsSqrt2 ? -0.5 : 0.0 );
  dErrScale                 = dErrScale*pow( 2.0, ( -2.0*dTransShift ) );                     // Compensate for scaling through forward transform
  const int  QStep          = g_quantScales[needsSqrt2?1:0][qp];
  double    finalErrScale = dErrScale / QStep / QStep / (1 << (DISTORTION_PRECISION_ADJUSTMENT(channelBitDepth) << 1));
  return    finalErrScale;
}
#else
double QuantRDOQ::xGetErrScaleCoeff( const bool needsSqrt2, SizeType width, SizeType height, int qp, const int maxLog2TrDynamicRange, const int channelBitDepth )
{
  const int iTransformShift = getTransformShift(channelBitDepth, Size(width, height), maxLog2TrDynamicRange);
#if HM_QTBT_AS_IN_JEM_QUANT
  double    dErrScale       = (double)( 1 << SCALE_BITS );                                // Compensate for scaling of bitcount in Lagrange cost function
  double    dTransShift     = (double)iTransformShift + ( needsSqrt2 ? -0.5 : 0.0 );
  dErrScale                 = dErrScale*pow( 2.0, ( -2.0*dTransShift ) );                     // Compensate for scaling through forward transform
  int       QStep           = ( needsSqrt2 ? ( ( g_quantScales[qp] * 181 ) >> 7 ) : g_quantScales[qp] );
  double    finalErrScale = dErrScale / QStep / QStep / (1 << (DISTORTION_PRECISION_ADJUSTMENT(channelBitDepth) << 1));
#else
  int errShift = SCALE_BITS - ((iTransformShift + DISTORTION_PRECISION_ADJUSTMENT(channelBitDepth)) << 1);
  double    dErrScale       = exp2( double( errShift ) );
  double    finalErrScale   = dErrScale / double( g_quantScales[qp] * g_quantScales[qp] );
#endif
  return    finalErrScale;
}
#endif
#endif



#if HEVC_USE_SCALING_LISTS
/** set error scale coefficients
 * \param list                   list ID
 * \param size
 * \param qp                     quantization parameter
 * \param maxLog2TrDynamicRange
 * \param bitDepths              reference to bit depth array for all channels
 */
void QuantRDOQ::xSetErrScaleCoeff( uint32_t list, uint32_t sizeX, uint32_t sizeY, int qp, const int maxLog2TrDynamicRange[MAX_NUM_CHANNEL_TYPE], const BitDepths &bitDepths )
{
  const int width = g_scalingListSizeX[sizeX];
  const int height = g_scalingListSizeX[sizeY];
  const ChannelType channelType = ( ( list == 0 ) || ( list == MAX_NUM_COMPONENT ) ) ? CHANNEL_TYPE_LUMA : CHANNEL_TYPE_CHROMA;
  const int channelBitDepth = bitDepths.recon[channelType];
  const int iTransformShift = getTransformShift( channelBitDepth, Size( g_scalingListSizeX[sizeX], g_scalingListSizeX[sizeY] ), maxLog2TrDynamicRange[channelType] );  // Represents scaling through forward transform

  uint32_t i, uiMaxNumCoeff = width * height;
  int *piQuantcoeff;
  double *pdErrScale;
  piQuantcoeff = getQuantCoeff( list, qp, sizeX, sizeY );
  pdErrScale   = xGetErrScaleCoeff( list, sizeX, sizeY, qp );

#if HM_QTBT_AS_IN_JEM_QUANT
  double dErrScale = (double)( 1 << SCALE_BITS );                                // Compensate for scaling of bitcount in Lagrange cost function

#if JVET_N0246_MODIFIED_QUANTSCALES
  const bool needsSqrt2 = ((g_aucLog2[width] + g_aucLog2[height]) & 1) == 1;
#else // !JVET_N0246_MODIFIED_QUANTSCALES
  bool   needsSqrt2 = TU::needsBlockSizeTrafoScale( Size( g_scalingListSizeX[sizeX], g_scalingListSizeX[sizeY] ) );// ( ( (sizeX+sizeY) & 1 ) !=0 );
#endif // JVET_N0246_MODIFIED_QUANTSCALES
  double dTransShift = (double)iTransformShift + ( needsSqrt2 ? -0.5 : 0.0 );
  dErrScale = dErrScale*pow( 2.0, ( -2.0*dTransShift ) );                     // Compensate for scaling through forward transform

  for( i = 0; i < uiMaxNumCoeff; i++ )
  {
    pdErrScale[i] = dErrScale / piQuantcoeff[i] / piQuantcoeff[i]
                    / (1 << (DISTORTION_PRECISION_ADJUSTMENT(bitDepths.recon[channelType]) << 1));
  }

#if JVET_N0246_MODIFIED_QUANTSCALES
  int QStep = g_quantScales[needsSqrt2][qp];
#else
  int QStep = ( needsSqrt2 ? ( ( g_quantScales[qp] * 181 ) >> 7 ) : g_quantScales[qp] );
#endif

  xGetErrScaleCoeffNoScalingList(list, sizeX, sizeY, qp) =
    dErrScale / QStep / QStep / (1 << (DISTORTION_PRECISION_ADJUSTMENT(bitDepths.recon[channelType]) << 1));
#else
  int errShift = SCALE_BITS - ((iTransformShift + DISTORTION_PRECISION_ADJUSTMENT(bitDepths.recon[channelType])) << 1);
  double dErrScale = exp2( double( errShift ) );
  for( i = 0; i < uiMaxNumCoeff; i++ )
  {
    pdErrScale[i] = dErrScale / double( piQuantcoeff[i] * piQuantcoeff[i] );
  }
  xGetErrScaleCoeffNoScalingList( list, sizeX, sizeY, qp ) = dErrScale / double( g_quantScales[qp] * g_quantScales[qp] );
#endif
}

/** set flat matrix value to quantized coefficient
 */
void QuantRDOQ::setFlatScalingList(const int maxLog2TrDynamicRange[MAX_NUM_CHANNEL_TYPE], const BitDepths &bitDepths)
{
  Quant::setFlatScalingList( maxLog2TrDynamicRange, bitDepths );

  const int minimumQp = 0;
  const int maximumQp = SCALING_LIST_REM_NUM;

  for(uint32_t sizeX = 0; sizeX < SCALING_LIST_SIZE_NUM; sizeX++)
  {
    for(uint32_t sizeY = 0; sizeY < SCALING_LIST_SIZE_NUM; sizeY++)
    {
      for(uint32_t list = 0; list < SCALING_LIST_NUM; list++)
      {
        for(int qp = minimumQp; qp < maximumQp; qp++)
        {
          xSetErrScaleCoeff( list, sizeX, sizeY, qp, maxLog2TrDynamicRange, bitDepths );
        }
      }
    }
  }
}

/** initialization process of scaling list array
 */
void QuantRDOQ::xInitScalingList( const QuantRDOQ* other )
{
  m_isErrScaleListOwner = other == nullptr;

  for(uint32_t sizeIdX = 0; sizeIdX < SCALING_LIST_SIZE_NUM; sizeIdX++)
  {
    for(uint32_t sizeIdY = 0; sizeIdY < SCALING_LIST_SIZE_NUM; sizeIdY++)
    {
      for(uint32_t qp = 0; qp < SCALING_LIST_REM_NUM; qp++)
      {
        for(uint32_t listId = 0; listId < SCALING_LIST_NUM; listId++)
        {
          if( m_isErrScaleListOwner )
          {
            m_errScale[sizeIdX][sizeIdY][listId][qp] = new double[g_scalingListSizeX[sizeIdX] * g_scalingListSizeX[sizeIdY]];
          }
          else
          {
            m_errScale[sizeIdX][sizeIdY][listId][qp] = other->m_errScale[sizeIdX][sizeIdY][listId][qp];
          }
        } // listID loop
      }
    }
  }
}

/** destroy quantization matrix array
 */
void QuantRDOQ::xDestroyScalingList()
{
  if( !m_isErrScaleListOwner ) return;

  for(uint32_t sizeIdX = 0; sizeIdX < SCALING_LIST_SIZE_NUM; sizeIdX++)
  {
    for(uint32_t sizeIdY = 0; sizeIdY < SCALING_LIST_SIZE_NUM; sizeIdY++)
    {
      for(uint32_t listId = 0; listId < SCALING_LIST_NUM; listId++)
      {
        for(uint32_t qp = 0; qp < SCALING_LIST_REM_NUM; qp++)
        {
          if(m_errScale[sizeIdX][sizeIdY][listId][qp])
          {
            delete [] m_errScale[sizeIdX][sizeIdY][listId][qp];
          }
        }
      }
    }
  }
//   Quant::destroyScalingList();
}
#endif


void QuantRDOQ::quant(TransformUnit &tu, const ComponentID &compID, const CCoeffBuf &pSrc, TCoeff &uiAbsSum, const QpParam &cQP, const Ctx& ctx)
{
  const CompArea &rect      = tu.blocks[compID];
  const uint32_t uiWidth        = rect.width;
  const uint32_t uiHeight       = rect.height;

  const CCoeffBuf &piCoef   = pSrc;
        CoeffBuf   piQCoef  = tu.getCoeffs(compID);

  const bool useTransformSkip      = tu.mtsIdx==MTS_SKIP;

  bool useRDOQ = useTransformSkip ? m_useRDOQTS : m_useRDOQ;

  if( !tu.cu->ispMode || !isLuma(compID) )
  {
    useRDOQ &= uiWidth > 2;
    useRDOQ &= uiHeight > 2;
  }

  if (useRDOQ && (isLuma(compID) || RDOQ_CHROMA))
  {
#if T0196_SELECTIVE_RDOQ
    if (!m_useSelectiveRDOQ || xNeedRDOQ(tu, compID, piCoef, cQP))
    {
#endif
#if JVET_N0280_RESIDUAL_CODING_TS
      if( isLuma( compID ) && useTransformSkip )
      {
#if JVET_N0413_RDPCM
        if( tu.cu->bdpcmMode && isLuma(compID) )
        {
          forwardRDPCM( tu, compID, pSrc, uiAbsSum, cQP, ctx );
        }
        else
        {
          xRateDistOptQuantTS( tu, compID, pSrc, uiAbsSum, cQP, ctx );
        }
#else
        xRateDistOptQuantTS( tu, compID, pSrc, uiAbsSum, cQP, ctx );
#endif
      }
      else
      {
        xRateDistOptQuant( tu, compID, pSrc, uiAbsSum, cQP, ctx );
      }
#else
      xRateDistOptQuant( tu, compID, pSrc, uiAbsSum, cQP, ctx );
#endif
#if T0196_SELECTIVE_RDOQ
    }
    else
    {
      piQCoef.fill(0);
      uiAbsSum = 0;
    }
#endif
  }
  else
  {
    Quant::quant( tu, compID, pSrc, uiAbsSum, cQP, ctx );
  }
}



void QuantRDOQ::xRateDistOptQuant(TransformUnit &tu, const ComponentID &compID, const CCoeffBuf &pSrc, TCoeff &uiAbsSum, const QpParam &cQP, const Ctx &ctx)
{
  const FracBitsAccess& fracBits = ctx.getFracBitsAcess();

  const SPS &sps            = *tu.cs->sps;
  const CompArea &rect      = tu.blocks[compID];
  const uint32_t uiWidth        = rect.width;
  const uint32_t uiHeight       = rect.height;
  const ChannelType chType  = toChannelType(compID);
  const int channelBitDepth = sps.getBitDepth( chType );

  const bool extendedPrecision     = sps.getSpsRangeExtension().getExtendedPrecisionProcessingFlag();
  const int  maxLog2TrDynamicRange = sps.getMaxLog2TrDynamicRange(chType);

  const bool useIntraSubPartitions = tu.cu->ispMode && isLuma(compID);
  /* for 422 chroma blocks, the effective scaling applied during transformation is not a power of 2, hence it cannot be
  * implemented as a bit-shift (the quantised result will be sqrt(2) * larger than required). Alternatively, adjust the
  * uiLog2TrSize applied in iTransformShift, such that the result is 1/sqrt(2) the required result (i.e. smaller)
  * Then a QP+3 (sqrt(2)) or QP-3 (1/sqrt(2)) method could be used to get the required result
  */

  // Represents scaling through forward transform
  int iTransformShift = getTransformShift(channelBitDepth, rect.size(), maxLog2TrDynamicRange);

  if (tu.mtsIdx==MTS_SKIP && extendedPrecision)
  {
    iTransformShift = std::max<int>(0, iTransformShift);
  }

  double     d64BlockUncodedCost               = 0;
  const uint32_t uiLog2BlockWidth                  = g_aucLog2[uiWidth];
#if HEVC_USE_SCALING_LISTS
  const uint32_t uiLog2BlockHeight                 = g_aucLog2[uiHeight];
#endif
  const uint32_t uiMaxNumCoeff                     = rect.area();

  CHECK(compID >= MAX_NUM_TBLOCKS, "Invalid component ID");

#if HEVC_USE_SCALING_LISTS
  int scalingListType = getScalingListType(tu.cu->predMode, compID);

  CHECK(scalingListType >= SCALING_LIST_NUM, "Invalid scaling list");
#endif

  const TCoeff *plSrcCoeff = pSrc.buf;
        TCoeff *piDstCoeff = tu.getCoeffs(compID).buf;

  double *pdCostCoeff  = m_pdCostCoeff;
  double *pdCostSig    = m_pdCostSig;
  double *pdCostCoeff0 = m_pdCostCoeff0;
#if HEVC_USE_SIGN_HIDING
  int    *rateIncUp    = m_rateIncUp;
  int    *rateIncDown  = m_rateIncDown;
  int    *sigRateDelta = m_sigRateDelta;
  TCoeff *deltaU       = m_deltaU;
#endif

  memset(piDstCoeff, 0, sizeof(*piDstCoeff) * uiMaxNumCoeff);
  memset( m_pdCostCoeff,  0, sizeof( double ) *  uiMaxNumCoeff );
  memset( m_pdCostSig,    0, sizeof( double ) *  uiMaxNumCoeff );
#if HEVC_USE_SIGN_HIDING
  memset( m_rateIncUp,    0, sizeof( int    ) *  uiMaxNumCoeff );
  memset( m_rateIncDown,  0, sizeof( int    ) *  uiMaxNumCoeff );
  memset( m_sigRateDelta, 0, sizeof( int    ) *  uiMaxNumCoeff );
  memset( m_deltaU,       0, sizeof( TCoeff ) *  uiMaxNumCoeff );
#endif


#if JVET_N0246_MODIFIED_QUANTSCALES
  const bool needSqrtAdjustment= TU::needsBlockSizeTrafoScale( tu, compID );
#if HEVC_USE_SCALING_LISTS
  const double *const pdErrScale = xGetErrScaleCoeff(scalingListType, (uiLog2BlockWidth-1), (uiLog2BlockHeight-1), cQP.rem);
  const int    *const piQCoef    = getQuantCoeff(scalingListType, cQP.rem, (uiLog2BlockWidth-1), (uiLog2BlockHeight-1));
  const bool   isTransformSkip = tu.mtsIdx==MTS_SKIP && isLuma(compID);
  const bool   enableScalingLists             = getUseScalingList(uiWidth, uiHeight, isTransformSkip);
  const int    defaultQuantisationCoefficient = g_quantScales[ needSqrtAdjustment ?1:0][cQP.rem];
  const double defaultErrorScale              = xGetErrScaleCoeffNoScalingList(scalingListType, (uiLog2BlockWidth-1), (uiLog2BlockHeight-1), cQP.rem);
  const int iQBits = QUANT_SHIFT + cQP.per + iTransformShift + (needSqrtAdjustment?-1:0);                   // Right shift of non-RDOQ quantizer;  level = (coeff*uiQ + offset)>>q_bits
#else
  const int quantisationCoefficient    = g_quantScales[needSqrtAdjustment?1:0][cQP.rem];
  const double errorScale = xGetErrScaleCoeff( TU::needsSqrt2Scale( tu, compID ), uiWidth, uiHeight, cQP.rem, maxLog2TrDynamicRange, channelBitDepth );
  const int iQBits = QUANT_SHIFT + cQP.per + iTransformShift + (needSqrtAdjustment?-1:0);                   // Right shift of non-RDOQ quantizer;  level = (coeff*uiQ + offset)>>q_bits
#endif // HEVC_USE_SCALING_LISTS
#else // JVET_N0246_MODIFIED_QUANTSCALES
  const int iQBits = QUANT_SHIFT + cQP.per + iTransformShift;                   // Right shift of non-RDOQ quantizer;  level = (coeff*uiQ + offset)>>q_bits

#if HEVC_USE_SCALING_LISTS
  const double *const pdErrScale = xGetErrScaleCoeff(scalingListType, (uiLog2BlockWidth-1), (uiLog2BlockHeight-1), cQP.rem);
  const int    *const piQCoef    = getQuantCoeff(scalingListType, cQP.rem, (uiLog2BlockWidth-1), (uiLog2BlockHeight-1));

  const bool   enableScalingLists             = getUseScalingList(uiWidth, uiHeight, tu.transformSkip[compID]);
#if HM_QTBT_AS_IN_JEM_QUANT
  const int    defaultQuantisationCoefficient = ( TU::needsSqrt2Scale( rect, tu.transformSkip[compID] ) ? ( g_quantScales[cQP.rem] * 181 ) >> 7 : g_quantScales[cQP.rem] );
  const double defaultErrorScale              = xGetErrScaleCoeffNoScalingList(scalingListType, (uiLog2BlockWidth-1), (uiLog2BlockHeight-1), cQP.rem);
#else
  const double blkErrScale                    = ( TU::needsQP3Offset( tu, compID ) ? 2.0 : 1.0 );
  const int    defaultQuantisationCoefficient = g_quantScales[cQP.rem];
  const double defaultErrorScale              = blkErrScale * xGetErrScaleCoeffNoScalingList( scalingListType, ( uiLog2BlockWidth - 1 ), ( uiLog2BlockHeight - 1 ), cQP.rem );
#endif
#else //HEVC_USE_SCALING_LISTS
#if HM_QTBT_AS_IN_JEM_QUANT
  const int    quantisationCoefficient = ( TU::needsSqrt2Scale( tu, compID ) ? ( g_quantScales[cQP.rem] * 181 ) >> 7 : g_quantScales[cQP.rem] );
  const double errorScale              = xGetErrScaleCoeff( TU::needsSqrt2Scale( tu, compID ), uiWidth, uiHeight, cQP.rem, maxLog2TrDynamicRange, channelBitDepth );
#else
  const double blkErrScale             = ( TU::needsQP3Offset( tu, compID ) ? 2.0 : 1.0 );
  const int    quantisationCoefficient = g_quantScales[cQP.rem];
  const double errorScale              = blkErrScale * xGetErrScaleCoeff( uiWidth, uiHeight, cQP.rem, maxLog2TrDynamicRange, channelBitDepth );
#endif
#endif//HEVC_USE_SCALING_LISTS
#endif // JVET_N0246_MODIFIED_QUANTSCALES


#if HEVC_USE_SIGN_HIDING
  const TCoeff entropyCodingMinimum = -(1 << maxLog2TrDynamicRange);
#endif
  const TCoeff entropyCodingMaximum =  (1 << maxLog2TrDynamicRange) - 1;

#if HEVC_USE_SIGN_HIDING
  CoeffCodingContext cctx(tu, compID, tu.cs->slice->getSignDataHidingEnabledFlag());
#else
  CoeffCodingContext cctx(tu, compID);
#endif
  const int    iCGSizeM1      = (1 << cctx.log2CGSize()) - 1;

  int     iCGLastScanPos      = -1;
  double  d64BaseCost         = 0;
  int     iLastScanPos        = -1;

  bool      is2x2subblock = ( iCGSizeM1 == 3 );
  int       remGt2Bins    = ( is2x2subblock ? MAX_NUM_GT2_BINS_2x2SUBBLOCK : MAX_NUM_GT2_BINS_4x4SUBBLOCK );
  int       remRegBins    = ( is2x2subblock ? MAX_NUM_REG_BINS_2x2SUBBLOCK : MAX_NUM_REG_BINS_4x4SUBBLOCK );
  uint32_t  goRiceParam   = 0;

  double *pdCostCoeffGroupSig = m_pdCostCoeffGroupSig;
  memset( pdCostCoeffGroupSig, 0, ( uiMaxNumCoeff >> cctx.log2CGSize() ) * sizeof( double ) );
  const int iCGNum = std::min<int>(JVET_C0024_ZERO_OUT_TH, uiWidth) * std::min<int>(JVET_C0024_ZERO_OUT_TH, uiHeight) >> cctx.log2CGSize();
  int iScanPos;
  coeffGroupRDStats rdStats;

#if ENABLE_TRACING
  DTRACE( g_trace_ctx, D_RDOQ, "%d: %3d, %3d, %dx%d, comp=%d\n", DTRACE_GET_COUNTER( g_trace_ctx, D_RDOQ ), rect.x, rect.y, rect.width, rect.height, compID );
#endif

#if JVET_N0193_LFNST
  const uint32_t lfnstIdx = tu.cu->lfnstIdx;
#endif


  for (int subSetId = iCGNum - 1; subSetId >= 0; subSetId--)
  {
    cctx.initSubblock( subSetId );

#if JVET_N0193_LFNST
    uint32_t maxNonZeroPosInCG = iCGSizeM1;
    if( lfnstIdx > 0 && ( ( uiWidth == 4 && uiHeight == 4 ) || ( uiWidth == 8 && uiHeight == 8 && cctx.cgPosX() == 0 && cctx.cgPosY() == 0 ) ) )
    {
      maxNonZeroPosInCG = 7;
    }
#endif

    memset( &rdStats, 0, sizeof (coeffGroupRDStats));

#if JVET_N0193_LFNST
    for( int iScanPosinCG = iCGSizeM1; iScanPosinCG > maxNonZeroPosInCG; iScanPosinCG-- )
    {
      iScanPos = cctx.minSubPos() + iScanPosinCG;
      uint32_t    blkPos = cctx.blockPos( iScanPos );
      piDstCoeff[ blkPos ] = 0;
    }
    for( int iScanPosinCG = maxNonZeroPosInCG; iScanPosinCG >= 0; iScanPosinCG-- )
#else
    for (int iScanPosinCG = iCGSizeM1; iScanPosinCG >= 0; iScanPosinCG--)
#endif
    {
      iScanPos = cctx.minSubPos() + iScanPosinCG;
      //===== quantization =====
      uint32_t    uiBlkPos          = cctx.blockPos(iScanPos);

      // set coeff
#if HEVC_USE_SCALING_LISTS
      const int    quantisationCoefficient = (enableScalingLists) ? piQCoef   [uiBlkPos]               : defaultQuantisationCoefficient;
#if HM_QTBT_AS_IN_JEM_QUANT
      const double errorScale              = (enableScalingLists) ? pdErrScale[uiBlkPos]               : defaultErrorScale;
#else
      const double errorScale              = (enableScalingLists) ? pdErrScale[uiBlkPos] * blkErrScale : defaultErrorScale;
#endif
#endif
      const int64_t  tmpLevel                = int64_t(abs(plSrcCoeff[ uiBlkPos ])) * quantisationCoefficient;

      const Intermediate_Int lLevelDouble  = (Intermediate_Int)std::min<int64_t>(tmpLevel, std::numeric_limits<Intermediate_Int>::max() - (Intermediate_Int(1) << (iQBits - 1)));

      uint32_t uiMaxAbsLevel        = std::min<uint32_t>(uint32_t(entropyCodingMaximum), uint32_t((lLevelDouble + (Intermediate_Int(1) << (iQBits - 1))) >> iQBits));

      const double dErr         = double( lLevelDouble );
      pdCostCoeff0[ iScanPos ]  = dErr * dErr * errorScale;
      d64BlockUncodedCost      += pdCostCoeff0[ iScanPos ];
      piDstCoeff[ uiBlkPos ]    = uiMaxAbsLevel;

      if ( uiMaxAbsLevel > 0 && iLastScanPos < 0 )
      {
        iLastScanPos            = iScanPos;
        iCGLastScanPos          = cctx.subSetId();
      }

      if ( iLastScanPos >= 0 )
      {

#if ENABLE_TRACING
        uint32_t uiCGPosY = cctx.cgPosX();
        uint32_t uiCGPosX = cctx.cgPosY();
        uint32_t uiPosY = cctx.posY( iScanPos );
        uint32_t uiPosX = cctx.posX( iScanPos );
        DTRACE( g_trace_ctx, D_RDOQ, "%d [%d][%d][%2d:%2d][%2d:%2d]", DTRACE_GET_COUNTER( g_trace_ctx, D_RDOQ ), iScanPos, uiBlkPos, uiCGPosX, uiCGPosY, uiPosX, uiPosY );
#endif
        //===== coefficient level estimation =====
        unsigned ctxIdSig = 0;
        if( iScanPos != iLastScanPos )
        {
          ctxIdSig = cctx.sigCtxIdAbs( iScanPos, piDstCoeff, 0 );
        }
        uint32_t    uiLevel;
        uint8_t ctxOffset     = cctx.ctxOffsetAbs     ();
        uint32_t    uiParCtx      = cctx.parityCtxIdAbs   ( ctxOffset );
        uint32_t    uiGt1Ctx      = cctx.greater1CtxIdAbs ( ctxOffset );
        uint32_t    uiGt2Ctx      = cctx.greater2CtxIdAbs ( ctxOffset );
        uint32_t    goRiceZero    = 0;
        if( remRegBins < 4 )
        {
#if JVET_N0188_UNIFY_RICEPARA
          unsigned  sumAbs = cctx.templateAbsSum( iScanPos, piDstCoeff, 0 );
#else
          unsigned  sumAbs        = cctx.templateAbsSum( iScanPos, piDstCoeff );
#endif
          goRiceParam             = g_auiGoRiceParsCoeff   [ sumAbs ];
          goRiceZero              = g_auiGoRicePosCoeff0[0][ sumAbs ];
        }

        const BinFracBits fracBitsPar = fracBits.getFracBitsArray( uiParCtx );
        const BinFracBits fracBitsGt1 = fracBits.getFracBitsArray( uiGt1Ctx );
        const BinFracBits fracBitsGt2 = fracBits.getFracBitsArray( uiGt2Ctx );

        if( iScanPos == iLastScanPos )
        {
          uiLevel = xGetCodedLevel( pdCostCoeff[ iScanPos ], pdCostCoeff0[ iScanPos ], pdCostSig[ iScanPos ],
                                    lLevelDouble, uiMaxAbsLevel, nullptr, fracBitsPar, fracBitsGt1, fracBitsGt2, remGt2Bins, remRegBins, goRiceZero, goRiceParam, iQBits, errorScale, 1, extendedPrecision, maxLog2TrDynamicRange );
        }
        else
        {
          DTRACE_COND( ( uiMaxAbsLevel != 0 ), g_trace_ctx, D_RDOQ_MORE, " uiCtxSig=%d", ctxIdSig );

          const BinFracBits fracBitsSig = fracBits.getFracBitsArray( ctxIdSig );
          uiLevel = xGetCodedLevel( pdCostCoeff[ iScanPos ], pdCostCoeff0[ iScanPos ], pdCostSig[ iScanPos ],
                                    lLevelDouble, uiMaxAbsLevel, &fracBitsSig, fracBitsPar, fracBitsGt1, fracBitsGt2, remGt2Bins, remRegBins, goRiceZero, goRiceParam, iQBits, errorScale, 0, extendedPrecision, maxLog2TrDynamicRange );
#if HEVC_USE_SIGN_HIDING
          sigRateDelta[ uiBlkPos ] = ( remRegBins < 4 ? 0 : fracBitsSig.intBits[1] - fracBitsSig.intBits[0] );
#endif
        }

        DTRACE( g_trace_ctx, D_RDOQ, " Lev=%d \n", uiLevel );
        DTRACE_COND( ( uiMaxAbsLevel != 0 ), g_trace_ctx, D_RDOQ, " CostC0=%d\n", (int64_t)( pdCostCoeff0[iScanPos] ) );
        DTRACE_COND( ( uiMaxAbsLevel != 0 ), g_trace_ctx, D_RDOQ, " CostC =%d\n", (int64_t)( pdCostCoeff[iScanPos] ) );

#if HEVC_USE_SIGN_HIDING
        deltaU[ uiBlkPos ]        = TCoeff((lLevelDouble - (Intermediate_Int(uiLevel) << iQBits)) >> (iQBits-8));

        if( uiLevel > 0 )
        {
          int rateNow              = xGetICRate( uiLevel,   fracBitsPar, fracBitsGt1, fracBitsGt2, remGt2Bins, remRegBins, goRiceZero, goRiceParam, extendedPrecision, maxLog2TrDynamicRange );
          rateIncUp   [ uiBlkPos ] = xGetICRate( uiLevel+1, fracBitsPar, fracBitsGt1, fracBitsGt2, remGt2Bins, remRegBins, goRiceZero, goRiceParam, extendedPrecision, maxLog2TrDynamicRange ) - rateNow;
          rateIncDown [ uiBlkPos ] = xGetICRate( uiLevel-1, fracBitsPar, fracBitsGt1, fracBitsGt2, remGt2Bins, remRegBins, goRiceZero, goRiceParam, extendedPrecision, maxLog2TrDynamicRange ) - rateNow;
        }
        else // uiLevel == 0
        {
          if( remRegBins < 4 )
          {
            int rateNow            = xGetICRate( uiLevel,   fracBitsPar, fracBitsGt1, fracBitsGt2, remGt2Bins, remRegBins, goRiceZero, goRiceParam, extendedPrecision, maxLog2TrDynamicRange );
            rateIncUp [ uiBlkPos ] = xGetICRate( uiLevel+1, fracBitsPar, fracBitsGt1, fracBitsGt2, remGt2Bins, remRegBins, goRiceZero, goRiceParam, extendedPrecision, maxLog2TrDynamicRange ) - rateNow;
          }
          else
          {
            rateIncUp [ uiBlkPos ] = fracBitsGt1.intBits[ 0 ];
          }
        }
#endif
        piDstCoeff[ uiBlkPos ] = uiLevel;
        d64BaseCost           += pdCostCoeff [ iScanPos ];

        if( ( (iScanPos & iCGSizeM1) == 0 ) && ( iScanPos > 0 ) )
        {
          remGt2Bins    = ( is2x2subblock ? MAX_NUM_GT2_BINS_2x2SUBBLOCK : MAX_NUM_GT2_BINS_4x4SUBBLOCK );
          remRegBins    = ( is2x2subblock ? MAX_NUM_REG_BINS_2x2SUBBLOCK : MAX_NUM_REG_BINS_4x4SUBBLOCK ) - remGt2Bins;
          goRiceParam   = 0;
        }
        else if( remRegBins >= 4 )
        {
#if JVET_N0188_UNIFY_RICEPARA
          int  sumAll = cctx.templateAbsSum(iScanPos, piDstCoeff, 4);
          goRiceParam = g_auiGoRiceParsCoeff[sumAll];
#else
          const uint32_t baseLevel = 4;
          if( goRiceParam < 3 && ((uiLevel-baseLevel)>>1) > (3<<goRiceParam)-1 )
          {
            goRiceParam++;
          }
#endif
          remRegBins -= (uiLevel < 2 ? uiLevel : 3) + (iScanPos != iLastScanPos);
        }
      }
      else
      {
        d64BaseCost    += pdCostCoeff0[ iScanPos ];
      }
      rdStats.d64SigCost += pdCostSig[ iScanPos ];
      if (iScanPosinCG == 0 )
      {
        rdStats.d64SigCost_0 = pdCostSig[ iScanPos ];
      }
      if (piDstCoeff[ uiBlkPos ] )
      {
        cctx.setSigGroup();
        rdStats.d64CodedLevelandDist += pdCostCoeff[ iScanPos ] - pdCostSig[ iScanPos ];
        rdStats.d64UncodedDist += pdCostCoeff0[ iScanPos ];
        if ( iScanPosinCG != 0 )
        {
          rdStats.iNNZbeforePos0++;
        }
      }
    } //end for (iScanPosinCG)

    if (iCGLastScanPos >= 0)
    {
      if( cctx.subSetId() )
      {
        if( !cctx.isSigGroup() )
        {
          const BinFracBits fracBitsSigGroup = fracBits.getFracBitsArray( cctx.sigGroupCtxId() );
          d64BaseCost += xGetRateSigCoeffGroup(fracBitsSigGroup, 0) - rdStats.d64SigCost;
          pdCostCoeffGroupSig[ cctx.subSetId() ] = xGetRateSigCoeffGroup(fracBitsSigGroup, 0);
        }
        else
        {
          if (cctx.subSetId() < iCGLastScanPos) //skip the last coefficient group, which will be handled together with last position below.
          {
            if ( rdStats.iNNZbeforePos0 == 0 )
            {
              d64BaseCost -= rdStats.d64SigCost_0;
              rdStats.d64SigCost -= rdStats.d64SigCost_0;
            }
            // rd-cost if SigCoeffGroupFlag = 0, initialization
            double d64CostZeroCG = d64BaseCost;

            const BinFracBits fracBitsSigGroup = fracBits.getFracBitsArray( cctx.sigGroupCtxId() );

            if (cctx.subSetId() < iCGLastScanPos)
            {
              d64BaseCost  += xGetRateSigCoeffGroup(fracBitsSigGroup,1);
              d64CostZeroCG += xGetRateSigCoeffGroup(fracBitsSigGroup,0);
              pdCostCoeffGroupSig[ cctx.subSetId() ] = xGetRateSigCoeffGroup(fracBitsSigGroup,1);
            }

            // try to convert the current coeff group from non-zero to all-zero
            d64CostZeroCG += rdStats.d64UncodedDist;  // distortion for resetting non-zero levels to zero levels
            d64CostZeroCG -= rdStats.d64CodedLevelandDist;   // distortion and level cost for keeping all non-zero levels
            d64CostZeroCG -= rdStats.d64SigCost;     // sig cost for all coeffs, including zero levels and non-zerl levels

                                                     // if we can save cost, change this block to all-zero block
            if ( d64CostZeroCG < d64BaseCost )
            {
              cctx.resetSigGroup();
              d64BaseCost = d64CostZeroCG;
              if (cctx.subSetId() < iCGLastScanPos)
              {
                pdCostCoeffGroupSig[ cctx.subSetId() ] = xGetRateSigCoeffGroup(fracBitsSigGroup,0);
              }
              // reset coeffs to 0 in this block
#if JVET_N0193_LFNST
              for( int iScanPosinCG = maxNonZeroPosInCG; iScanPosinCG >= 0; iScanPosinCG-- )
#else
              for (int iScanPosinCG = iCGSizeM1; iScanPosinCG >= 0; iScanPosinCG--)
#endif
              {
                iScanPos      = cctx.minSubPos() + iScanPosinCG;