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/** \file     SampleAdaptiveOffset.cpp

    \brief    sample adaptive offset class

*/

#include "SampleAdaptiveOffset.h"

#include "UnitTools.h"

#include "UnitPartitioner.h"

#include "CodingStructure.h"

#include "dtrace_codingstruct.h"

#include "dtrace_buffer.h"

#include <string.h>

#include <stdlib.h>

#include <math.h>

//! \ingroup CommonLib

//! \{

namespace vvenc {

void offsetBlock_core(const int channelBitDepth, const ClpRng& clpRng, int typeIdx, int* offset, int startIdx, 

                      const Pel* srcBlk, Pel* resBlk, ptrdiff_t srcStride, ptrdiff_t resStride, int width, int height, 

                      uint8_t availMask, std::vector<int8_t> &signLineBuf1, std::vector<int8_t> &signLineBuf2)

{

  int x, y, startX, startY, endX, endY, edgeType;

  int firstLineStartX, firstLineEndX, lastLineStartX, lastLineEndX;

  int8_t signLeft, signRight, signDown;

  const Pel* srcLine = srcBlk;

  Pel* resLine = resBlk;

  switch (typeIdx)

  {

  case SAO_TYPE_EO_0:

  {

    offset += 2;

    startX = availMask&LeftAvail ? 0 : 1;

    endX = availMask&RightAvail ? width : (width - 1);

    for (y = 0; y < height; y++)

    {

      signLeft = (int8_t)sgn(srcLine[startX] - srcLine[startX - 1]);

      for (x = startX; x < endX; x++)

      {

        signRight = (int8_t)sgn(srcLine[x] - srcLine[x + 1]);

        edgeType = signRight + signLeft;

        signLeft = -signRight;

        resLine[x] = ClipPel<int>(srcLine[x] + offset[edgeType], clpRng);

      }

      srcLine += srcStride;

      resLine += resStride;

    }

  }

  break;

  case SAO_TYPE_EO_90:

  {

    offset += 2;

    int8_t *signUpLine = &signLineBuf1[0];

    startY = availMask&AboveAvail ? 0 : 1;

    endY = availMask&BelowAvail ? height : height - 1;

    if (!(availMask&AboveAvail))

    {

      srcLine += srcStride;

      resLine += resStride;

    }

    const Pel* srcLineAbove = srcLine - srcStride;

    for (x = 0; x < width; x++)

    {

      signUpLine[x] = (int8_t)sgn(srcLine[x] - srcLineAbove[x]);

    }

    const Pel* srcLineBelow;

    for (y = startY; y < endY; y++)

    {

      srcLineBelow = srcLine + srcStride;

      for (x = 0; x < width; x++)

      {

        signDown = (int8_t)sgn(srcLine[x] - srcLineBelow[x]);

        edgeType = signDown + signUpLine[x];

        signUpLine[x] = -signDown;

        resLine[x] = ClipPel<int>(srcLine[x] + offset[edgeType], clpRng);

      }

      srcLine += srcStride;

      resLine += resStride;

    }

  }

  break;

  case SAO_TYPE_EO_135:

  {

    offset += 2;

    int8_t *signUpLine, *signDownLine, *signTmpLine;

    signUpLine = &signLineBuf1[0];

    signDownLine = &signLineBuf2[0];

    startX = availMask&LeftAvail ? 0 : 1;

    endX = availMask&RightAvail ? width : (width - 1);

    //prepare 2nd line's upper sign

    const Pel* srcLineBelow = srcLine + srcStride;

    for (x = startX; x < endX + 1; x++)

    {

      signUpLine[x] = (int8_t)sgn(srcLineBelow[x] - srcLine[x - 1]);

    }

    //1st line

    const Pel* srcLineAbove = srcLine - srcStride;

    firstLineStartX = availMask&AboveLeftAvail ? 0 : 1;

    firstLineEndX = availMask&AboveAvail ? endX : 1;

    for (x = firstLineStartX; x < firstLineEndX; x++)

    {

      edgeType = sgn(srcLine[x] - srcLineAbove[x - 1]) - signUpLine[x + 1];

      resLine[x] = ClipPel<int>(srcLine[x] + offset[edgeType], clpRng);

    }

    srcLine += srcStride;

    resLine += resStride;

    //middle lines

    for (y = 1; y < height - 1; y++)

    {

      srcLineBelow = srcLine + srcStride;

      for (x = startX; x < endX; x++)

      {

        signDown = (int8_t)sgn(srcLine[x] - srcLineBelow[x + 1]);

        edgeType = signDown + signUpLine[x];

        resLine[x] = ClipPel<int>(srcLine[x] + offset[edgeType], clpRng);

        signDownLine[x + 1] = -signDown;

      }

      signDownLine[startX] = (int8_t)sgn(srcLineBelow[startX] - srcLine[startX - 1]);

      signTmpLine = signUpLine;

      signUpLine = signDownLine;

      signDownLine = signTmpLine;

      srcLine += srcStride;

      resLine += resStride;

    }

    //last line

    srcLineBelow = srcLine + srcStride;

    lastLineStartX = availMask&BelowAvail ? startX : (width - 1);

    lastLineEndX = availMask&BelowRightAvail ? width : (width - 1);

    for (x = lastLineStartX; x < lastLineEndX; x++)

    {

      edgeType = sgn(srcLine[x] - srcLineBelow[x + 1]) + signUpLine[x];

      resLine[x] = ClipPel<int>(srcLine[x] + offset[edgeType], clpRng);

    }

  }

  break;

  case SAO_TYPE_EO_45:

  {

    offset += 2;

    int8_t *signUpLine = &signLineBuf1[1];

    startX = availMask&LeftAvail ? 0 : 1;

    endX = availMask&RightAvail ? width : (width - 1);

    //prepare 2nd line upper sign

    const Pel* srcLineBelow = srcLine + srcStride;

    for (x = startX - 1; x < endX; x++)

    {

      signUpLine[x] = (int8_t)sgn(srcLineBelow[x] - srcLine[x + 1]);

    }

    //first line

    const Pel* srcLineAbove = srcLine - srcStride;

    firstLineStartX = availMask&AboveAvail ? startX : (width - 1);

    firstLineEndX = availMask&AboveRightAvail ? width : (width - 1);

    for (x = firstLineStartX; x < firstLineEndX; x++)

    {

      edgeType = sgn(srcLine[x] - srcLineAbove[x + 1]) - signUpLine[x - 1];

      resLine[x] = ClipPel<int>(srcLine[x] + offset[edgeType], clpRng);

    }

    srcLine += srcStride;

    resLine += resStride;

    //middle lines

    for (y = 1; y < height - 1; y++)

    {

      srcLineBelow = srcLine + srcStride;

      for (x = startX; x < endX; x++)

      {

        signDown = (int8_t)sgn(srcLine[x] - srcLineBelow[x - 1]);

        edgeType = signDown + signUpLine[x];

        resLine[x] = ClipPel<int>(srcLine[x] + offset[edgeType], clpRng);

        signUpLine[x - 1] = -signDown;

      }

      signUpLine[endX - 1] = (int8_t)sgn(srcLineBelow[endX - 1] - srcLine[endX]);

      srcLine += srcStride;

      resLine += resStride;

    }

    //last line

    srcLineBelow = srcLine + srcStride;

    lastLineStartX = availMask&BelowLeftAvail ? 0 : 1;

    lastLineEndX = availMask&BelowAvail ? endX : 1;

    for (x = lastLineStartX; x < lastLineEndX; x++)

    {

      edgeType = sgn(srcLine[x] - srcLineBelow[x - 1]) + signUpLine[x];

      resLine[x] = ClipPel<int>(srcLine[x] + offset[edgeType], clpRng);

    }

  }

  break;

  case SAO_TYPE_BO:

  {

    const int shiftBits = channelBitDepth - NUM_SAO_BO_CLASSES_LOG2;

    for (y = 0; y < height; y++)

    {

      for (x = 0; x < width; x++)

      {

        resLine[x] = ClipPel<int>(srcLine[x] + offset[srcLine[x] >> shiftBits], clpRng);

      }

      srcLine += srcStride;

      resLine += resStride;

    }

  }

  break;

  default:

  {

    THROW("Not a supported SAO types\n");

  }

  }

}

void calcSaoStatisticsEo0_Core(int width,int startX,int endX,int endY,Pel*  srcLine,Pel*  orgLine,int srcStride,int orgStride,int64_t  *count, int64_t *diff)

{

  int iNaRight=width-endX;

  srcLine      = srcLine + startX;

  orgLine      =orgLine + startX;

  int iNaWidth = startX + iNaRight;

  int i,j;

  diff +=2;

  count+=2;

  for ( i = 0; i < endY; i++ )

  {

    int iSignLeft = sgn( *srcLine - *(srcLine - 1) );

    for ( j = 0; j < width - iNaWidth; j++, srcLine++, orgLine++ )

    {

      int iSignRight       = sgn( *srcLine - *(srcLine + 1) );

      int iType            = iSignLeft + iSignRight;

      iSignLeft            = -1 * iSignRight;

      diff[iType]  += (*orgLine - *srcLine);

      count[iType] += 1;

    }

    srcLine += srcStride - ( width - iNaWidth );

    orgLine += orgStride - ( width - iNaWidth );

  }

}

void calcSaoStatisticsEo90_Core(int width,int endX,int startY,int endY,Pel*  srcLine,Pel*  orgLine,int srcStride,int orgStride,int64_t  *count, int64_t *diff,int8_t *signUpLine)

{

  diff +=2;

  count+=2;

  int x,y,edgeType;

  Pel* srcLineAbove = srcLine - srcStride;

  int8_t signDown;

  for (x=0; x<endX; x++)

  {

    signUpLine[x] = (int8_t)sgn(srcLine[x] - srcLineAbove[x]);

  }

  Pel* srcLineBelow;

  for (y=startY; y<endY; y++)

  {

    srcLineBelow = srcLine + srcStride;

    for (x=0; x<endX; x++)

    {

      signDown  = (int8_t)sgn(srcLine[x] - srcLineBelow[x]);

      edgeType  = signDown + signUpLine[x];

      signUpLine[x]= -signDown;

      diff [edgeType] += (orgLine[x] - srcLine[x]);

      count[edgeType] ++;

    }

    srcLine += srcStride;

    orgLine += orgStride;

  }

}

void calcSaoStatisticsEo135_Core(int width,int startX,int endX,int endY,Pel*  srcLine,Pel*  orgLine,int srcStride,int orgStride,int64_t  *count, int64_t *diff,int8_t *signUpLine,int8_t *signDownLine)

{

  int x,y,edgeType;

  int8_t signDown;

  int8_t *signTmpLine;

  Pel* srcLineBelow = srcLine + srcStride;

  //middle lines

   for (y=1; y<endY; y++)

   {

     srcLineBelow = srcLine + srcStride;

     for (x=startX; x<endX; x++)

     {

       signDown = (int8_t)sgn(srcLine[x] - srcLineBelow[x+1]);

       edgeType = signDown + signUpLine[x];

       diff [edgeType] += (orgLine[x] - srcLine[x]);

       count[edgeType] ++;

       signDownLine[x+1] = -signDown;

     }

     signDownLine[startX] = (int8_t)sgn(srcLineBelow[startX] - srcLine[startX-1]);

     signTmpLine  = signUpLine;

     signUpLine   = signDownLine;

     signDownLine = signTmpLine;

     srcLine += srcStride;

     orgLine += orgStride;

   }

}

void calcSaoStatisticsEo45_Core(int width,int startX,int endX,int endY,Pel*  srcLine,Pel*  orgLine,int srcStride,int orgStride,int64_t  *count, int64_t *diff,int8_t *signUpLine)

{

  int x,y,edgeType;

  int8_t signDown;

  Pel* srcLineBelow = srcLine + srcStride;

  //middle lines

  for (y=1; y<endY; y++)

  {

    srcLineBelow = srcLine + srcStride;

    for(x=startX; x<endX; x++)

    {

      signDown = (int8_t)sgn(srcLine[x] - srcLineBelow[x-1]);

      edgeType = signDown + signUpLine[x];

      diff [edgeType] += (orgLine[x] - srcLine[x]);

      count[edgeType] ++;

      signUpLine[x-1] = -signDown;

    }

    signUpLine[endX-1] = (int8_t)sgn(srcLineBelow[endX-1] - srcLine[endX]);

    srcLine  += srcStride;

    orgLine  += orgStride;

  }

}

void calcSaoStatisticsBo_Core(int width,int endX,int endY,Pel*  srcLine,Pel*  orgLine,int srcStride,int orgStride,int channelBitDepth, int64_t *count,int64_t  *diff)

{

  int x,y;

  int startX=0;

  int shiftBits = channelBitDepth - NUM_SAO_BO_CLASSES_LOG2;

  for (y=0; y< endY; y++)

  {

    for (x=startX; x< endX; x++)

    {

      int bandIdx= srcLine[x] >> shiftBits;

      diff [bandIdx] += (orgLine[x] - srcLine[x]);

      count[bandIdx] ++;

    }

    srcLine += srcStride;

    orgLine += orgStride;

  }

}

void SAOOffset::reset()

{

  modeIdc = SAO_MODE_OFF;

  typeIdc = -1;

  typeAuxInfo = -1;

  ::memset(offset, 0, sizeof(int)* MAX_NUM_SAO_CLASSES);

}

void SAOBlkParam::reset()

{

  for(int compIdx = 0; compIdx < MAX_NUM_COMP; compIdx++)

  {

    SAOOffsets[compIdx].reset();

  }

}

SampleAdaptiveOffset::SampleAdaptiveOffset( bool enableOpt )

{

  offsetBlock = offsetBlock_core;

  calcSaoStatisticsEo90 = calcSaoStatisticsEo90_Core;

  calcSaoStatisticsEo135 = calcSaoStatisticsEo135_Core;

  calcSaoStatisticsEo45 = calcSaoStatisticsEo45_Core;

  calcSaoStatisticsEo0 = calcSaoStatisticsEo0_Core;

  calcSaoStatisticsBo = calcSaoStatisticsBo_Core;

  if( enableOpt )

  {

#if ENABLE_SIMD_OPT_SAO && defined( TARGET_SIMD_X86 )

    initSampleAdaptiveOffsetX86();

#endif

#if ENABLE_SIMD_OPT_SAO && defined( TARGET_SIMD_ARM )

    initSampleAdaptiveOffsetARM();

#endif

  }

}

SampleAdaptiveOffset::~SampleAdaptiveOffset()

{

  m_signLineBuf1.clear();

  m_signLineBuf2.clear();

}

void SampleAdaptiveOffset::init( ChromaFormat format, uint32_t maxCUWidth, uint32_t maxCUHeight, uint32_t lumaBitShift, uint32_t chromaBitShift )

{

  //bit-depth related

  for(int compIdx = 0; compIdx < MAX_NUM_COMP; compIdx++)

  {

    m_offsetStepLog2  [compIdx] = isLuma(ComponentID(compIdx))? lumaBitShift : chromaBitShift;

  }

  m_numberOfComponents = getNumberValidComponents(format);

  size_t lineBufferSize = std::max( maxCUWidth, maxCUHeight ) + 1;

  if( m_signLineBuf1.size() < lineBufferSize )

  {

    m_signLineBuf1.resize( lineBufferSize );

    m_signLineBuf2.resize( lineBufferSize );

  }

}

void SampleAdaptiveOffset::invertQuantOffsets(ComponentID compIdx, int typeIdc, int typeAuxInfo, int* dstOffsets, int* srcOffsets)

{

  int codedOffset[MAX_NUM_SAO_CLASSES];

  ::memcpy(codedOffset, srcOffsets, sizeof(int)*MAX_NUM_SAO_CLASSES);

  ::memset(dstOffsets, 0, sizeof(int)*MAX_NUM_SAO_CLASSES);

  if(typeIdc == SAO_TYPE_START_BO)

  {

    for(int i=0; i< 4; i++)

    {

      dstOffsets[(typeAuxInfo+ i)%NUM_SAO_BO_CLASSES] = codedOffset[(typeAuxInfo+ i)%NUM_SAO_BO_CLASSES]*(1<<m_offsetStepLog2[compIdx]);

    }

  }

  else //EO

  {

    for(int i=0; i< NUM_SAO_EO_CLASSES; i++)

    {

      dstOffsets[i] = codedOffset[i] *(1<<m_offsetStepLog2[compIdx]);

    }

    CHECK(dstOffsets[SAO_CLASS_EO_PLAIN] != 0, "EO offset is not '0'"); //keep EO plain offset as zero

  }

}

int SampleAdaptiveOffset::getMergeList(CodingStructure& cs, int ctuRsAddr, SAOBlkParam* blkParams, SAOBlkParam* mergeList[NUM_SAO_MERGE_TYPES])

{

  const PreCalcValues& pcv = *cs.pcv;

  int ctuX = ctuRsAddr % pcv.widthInCtus;

  int ctuY = ctuRsAddr / pcv.widthInCtus;

  const CodingUnit& cu = *cs.getCU(Position(ctuX*pcv.maxCUSize, ctuY*pcv.maxCUSize), CH_L, TREE_D);

  int mergedCTUPos;

  int numValidMergeCandidates = 0;

  for(int mergeType=0; mergeType< NUM_SAO_MERGE_TYPES; mergeType++)

  {

    SAOBlkParam* mergeCandidate = NULL;

    switch(mergeType)

    {

    case SAO_MERGE_ABOVE:

      {

        if(ctuY > 0)

        {

          mergedCTUPos = ctuRsAddr- pcv.widthInCtus;

          if(cs.getCURestricted(Position(ctuX*pcv.maxCUSize, (ctuY-1)*pcv.maxCUSize), cu, cu.chType))

          {

            mergeCandidate = &(blkParams[mergedCTUPos]);

          }

        }

      }

      break;

    case SAO_MERGE_LEFT:

      {

        if(ctuX > 0)

        {

          mergedCTUPos = ctuRsAddr- 1;

          if(cs.getCURestricted(Position((ctuX-1)*pcv.maxCUSize, ctuY*pcv.maxCUSize), cu, cu.chType))

          {

            mergeCandidate = &(blkParams[mergedCTUPos]);

          }

        }

      }

      break;

    default:

      {

        THROW("not a supported merge type");

      }

    }

    mergeList[mergeType]=mergeCandidate;

    if (mergeCandidate != NULL)

    {

      numValidMergeCandidates++;

    }

  }

  return numValidMergeCandidates;

}

void SampleAdaptiveOffset::reconstructBlkSAOParam(SAOBlkParam& recParam, SAOBlkParam* mergeList[NUM_SAO_MERGE_TYPES])

{

  const int numberOfComponents = m_numberOfComponents;

  for(int compIdx = 0; compIdx < numberOfComponents; compIdx++)

  {

    const ComponentID component = ComponentID(compIdx);

    SAOOffset& offsetParam = recParam[component];

    if(offsetParam.modeIdc == SAO_MODE_OFF)

    {

      continue;

    }

    switch(offsetParam.modeIdc)

    {

    case SAO_MODE_NEW:

      {

        invertQuantOffsets(component, offsetParam.typeIdc, offsetParam.typeAuxInfo, offsetParam.offset, offsetParam.offset);

      }

      break;

    case SAO_MODE_MERGE:

      {

        SAOBlkParam* mergeTarget = mergeList[offsetParam.typeIdc];

        CHECK(mergeTarget == NULL, "Merge target does not exist");

        offsetParam = (*mergeTarget)[component];

      }

      break;

    default:

      {

        THROW("Not a supported mode");

      }

    }

  }

}

void SampleAdaptiveOffset::xReconstructBlkSAOParams(CodingStructure& cs, SAOBlkParam* saoBlkParams)

{

  for(uint32_t compIdx = 0; compIdx < MAX_NUM_COMP; compIdx++)

  {

    m_picSAOEnabled[compIdx] = false;

  }

  const uint32_t numberOfComponents = getNumberValidComponents(cs.pcv->chrFormat);

  for(int ctuRsAddr=0; ctuRsAddr< cs.pcv->sizeInCtus; ctuRsAddr++)

  {

    SAOBlkParam* mergeList[NUM_SAO_MERGE_TYPES] = { NULL };

    getMergeList(cs, ctuRsAddr, saoBlkParams, mergeList);

    reconstructBlkSAOParam(saoBlkParams[ctuRsAddr], mergeList);

    for(uint32_t compIdx = 0; compIdx < numberOfComponents; compIdx++)

    {

      if(saoBlkParams[ctuRsAddr][compIdx].modeIdc != SAO_MODE_OFF)

      {

        m_picSAOEnabled[compIdx] = true;

      }

    }

  }

}

void SampleAdaptiveOffset::offsetCTU( const UnitArea& area, const CPelUnitBuf& src, PelUnitBuf& res, SAOBlkParam& saoblkParam, CodingStructure& cs)

{

  const uint32_t numberOfComponents = getNumberValidComponents( area.chromaFormat );

  bool bAllOff=true;

  for( uint32_t compIdx = 0; compIdx < numberOfComponents; compIdx++)

  {

    if (saoblkParam[compIdx].modeIdc != SAO_MODE_OFF)

    {

      bAllOff=false;

    }

  }

  if (bAllOff)

  {

    return;

  }

  uint8_t availMask;

  //block boundary availability

  deriveLoopFilterBoundaryAvailibility(cs, area.Y(), availMask);

  const size_t lineBufferSize = area.Y().width + 1;

  if (m_signLineBuf1.size() < lineBufferSize)

  {

    m_signLineBuf1.resize(lineBufferSize);

    m_signLineBuf2.resize(lineBufferSize);

  }

  for(int compIdx = 0; compIdx < numberOfComponents; compIdx++)

  {

    const ComponentID compID = ComponentID(compIdx);

    const CompArea& compArea = area.block(compID);

    SAOOffset& ctbOffset     = saoblkParam[compIdx];

    if(ctbOffset.modeIdc != SAO_MODE_OFF)

    {

      int  srcStride    = src.get(compID).stride;

      const Pel* srcBlk = src.get(compID).bufAt(compArea);

      int  resStride    = res.get(compID).stride;

      Pel* resBlk       = res.get(compID).bufAt(compArea);

      offsetBlock( cs.sps->bitDepths[toChannelType(compID)],

                   cs.slice->clpRngs[compID],

                   ctbOffset.typeIdc, ctbOffset.offset, ctbOffset.typeAuxInfo

                  , srcBlk, resBlk, srcStride, resStride, compArea.width, compArea.height, availMask

                  , m_signLineBuf1, m_signLineBuf2 );

    }

  } //compIdx

}

void SampleAdaptiveOffset::deriveLoopFilterBoundaryAvailibility(CodingStructure& cs, const Position& pos, uint8_t& availMask ) const

{

  const int cuSize = cs.pcv->maxCUSize;

  CodingUnit *cuLeft, *cuRight, *cuAbove, *cuBelow, *cuAboveLeft, *cuAboveRight, *cuBelowLeft, *cuBelowRight;

  const CodingUnit *cuCurr = cs.getCU( pos, CH_L, TREE_D );

  if (!cs.pps->getSubPicFromCU(*cuCurr).loopFilterAcrossSubPicEnabled)

  {

    THROW("no support");

  }

  if( !cs.pps->loopFilterAcrossSlicesEnabled || !cs.pps->loopFilterAcrossTilesEnabled )

  {

    const int ctuX = pos.x >> cs.pcv->maxCUSizeLog2;

    const int ctuY = pos.y >> cs.pcv->maxCUSizeLog2;

    const PPS* pps = cs.slice->pps;

    const int Xmax = pps->pcv->widthInCtus  - 1;

    const int Ymax = pps->pcv->heightInCtus - 1;

    cuLeft       = ctuX > 0                   && pps->canFilterCtuBdry( ctuX, ctuY, -1, 0 ) ? cs.getCU( pos.offset( -cuSize, 0       ), CH_L, TREE_D ): nullptr;

    cuRight      = ctuX < Xmax                && pps->canFilterCtuBdry( ctuX, ctuY,  1, 0 ) ? cs.getCU( pos.offset( cuSize , 0       ), CH_L, TREE_D ): nullptr;

    cuAbove      =                ctuY > 0    && pps->canFilterCtuBdry( ctuX, ctuY,  0,-1 ) ? cs.getCU( pos.offset( 0      , -cuSize ), CH_L, TREE_D ): nullptr;

    cuBelow      =                ctuY < Ymax && pps->canFilterCtuBdry( ctuX, ctuY,  0, 1 ) ? cs.getCU( pos.offset( 0      , cuSize  ), CH_L, TREE_D ): nullptr;

    cuAboveLeft  = ctuX > 0    && ctuY > 0    && pps->canFilterCtuBdry( ctuX, ctuY, -1,-1 ) ? cs.getCU( pos.offset( -cuSize, -cuSize ), CH_L, TREE_D ): nullptr;

    cuAboveRight = ctuX < Xmax && ctuY > 0    && pps->canFilterCtuBdry( ctuX, ctuY,  1,-1 ) ? cs.getCU( pos.offset( cuSize , -cuSize ), CH_L, TREE_D ): nullptr;

    cuBelowLeft  = ctuX > 0    && ctuY < Ymax && pps->canFilterCtuBdry( ctuX, ctuY, -1, 1 ) ? cs.getCU( pos.offset( -cuSize, cuSize  ), CH_L, TREE_D ): nullptr;

    cuBelowRight = ctuX < Xmax && ctuY < Ymax && pps->canFilterCtuBdry( ctuX, ctuY,  1, 1 ) ? cs.getCU( pos.offset( cuSize , cuSize  ), CH_L, TREE_D ): nullptr;

  }

  else

  {

    cuLeft       = cs.getCU( pos.offset( -cuSize,       0 ), CH_L, TREE_D );

    cuRight      = cs.getCU( pos.offset(  cuSize,       0 ), CH_L, TREE_D );

    cuAbove      = cs.getCU( pos.offset(       0, -cuSize ), CH_L, TREE_D );

    cuBelow      = cs.getCU( pos.offset(       0,  cuSize ), CH_L, TREE_D );

    cuAboveLeft  = cs.getCU( pos.offset( -cuSize, -cuSize ), CH_L, TREE_D );

    cuAboveRight = cs.getCU( pos.offset(  cuSize, -cuSize ), CH_L, TREE_D );

    cuBelowLeft  = cs.getCU( pos.offset( -cuSize,  cuSize ), CH_L, TREE_D );

    cuBelowRight = cs.getCU( pos.offset(  cuSize,  cuSize ), CH_L, TREE_D );

  }

  availMask = 0;

  // check cross slice flags

  if( cs.pps->loopFilterAcrossSlicesEnabled )

  {

    availMask |= (cuLeft       != NULL) ? LeftAvail : 0;

    availMask |= (cuAbove      != NULL) ? AboveAvail : 0;

    availMask |= (cuRight      != NULL) ? RightAvail : 0;

    availMask |= (cuBelow      != NULL) ? BelowAvail : 0;

    availMask |= (cuAboveLeft  != NULL) ? AboveLeftAvail : 0;

    availMask |= (cuBelowRight != NULL) ? BelowRightAvail : 0;

    availMask |= (cuAboveRight != NULL) ? AboveRightAvail : 0;

    availMask |= (cuBelowLeft  != NULL) ? BelowLeftAvail : 0;

  }

  else

  {

    availMask |= ((cuLeft       != NULL) && CU::isSameSlice(*cuCurr, *cuLeft) ) ? LeftAvail : 0;

    availMask |= ((cuAbove      != NULL) && CU::isSameSlice(*cuCurr, *cuAbove) ) ? AboveAvail : 0;

    availMask |= ((cuRight      != NULL) && CU::isSameSlice(*cuCurr, *cuRight)) ? RightAvail : 0;

    availMask |= ((cuBelow      != NULL) && CU::isSameSlice(*cuCurr, *cuBelow) ) ? BelowAvail : 0;

    availMask |= ((cuAboveLeft  != NULL) && CU::isSameSlice(*cuCurr, *cuAboveLeft)) ?  AboveLeftAvail : 0;

    availMask |= ((cuBelowRight != NULL) && CU::isSameSlice(*cuCurr, *cuBelowRight) ) ? BelowRightAvail : 0;

    availMask |= ((cuAboveRight != NULL) && CU::isSameSlice(*cuCurr, *cuAboveRight) ) ? AboveRightAvail : 0;

    availMask |= ( (cuBelowLeft != NULL) && CU::isSameSlice(*cuCurr, *cuBelowLeft) ) ? BelowLeftAvail : 0;

  }

  // check cross tile flags

  if (!cs.pps->loopFilterAcrossTilesEnabled)

  {

    uint8_t availMaskTile = 0;

    availMaskTile |= (availMask&LeftAvail       && CU::isSameTile(*cuCurr, *cuLeft)) ? LeftAvail : 0;

    availMaskTile |= (availMask&AboveAvail      && CU::isSameTile(*cuCurr, *cuAbove)) ? AboveAvail : 0;

    availMaskTile |= (availMask&RightAvail      && CU::isSameTile(*cuCurr, *cuRight)) ? RightAvail : 0;

    availMaskTile |= (availMask&BelowAvail      && CU::isSameTile(*cuCurr, *cuBelow)) ? BelowAvail : 0;

    availMaskTile |= (availMask&AboveLeftAvail  && CU::isSameTile(*cuCurr, *cuAboveLeft)) ? AboveLeftAvail : 0;

    availMaskTile |= (availMask&AboveRightAvail &&CU::isSameTile(*cuCurr, *cuAboveRight)) ? AboveRightAvail : 0;

    availMaskTile |= (availMask&BelowLeftAvail  && CU::isSameTile(*cuCurr, *cuBelowLeft)) ? BelowLeftAvail : 0;

    availMaskTile |= (availMask&BelowRightAvail && CU::isSameTile(*cuCurr, *cuBelowRight)) ? BelowRightAvail : 0;

    availMask = availMaskTile;

  }

}

} // namespace vvenc

//! \}