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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 "CommonLib/dtrace_codingstruct.h"

#include "CommonLib/dtrace_buffer.h"

#include "CommonLib/TimeProfiler.h"

#include <string.h>

#include <stdlib.h>

#include <stdio.h>

#include <math.h>

namespace vvdec

{

void SampleAdaptiveOffset::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,

                                             bool                 isLeftAvail,

                                             bool                 isRightAvail,

                                             bool                 isAboveAvail,

                                             bool                 isBelowAvail,

                                             bool                 isAboveLeftAvail,

                                             bool                 isAboveRightAvail,

                                             bool                 isBelowLeftAvail,

                                             bool                 isBelowRightAvail,

                                             std::vector<int8_t>* m_signLineBuf1,

                                             std::vector<int8_t>* m_signLineBuf2,

                                             bool                 isCtuCrossedByVirtualBoundaries,

                                             int                  horVirBndryPos[],

                                             int                  verVirBndryPos[],

                                             int                  numHorVirBndry,

                                             int                  numVerVirBndry )

{

  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 = isLeftAvail ? 0 : 1;

    endX   = isRightAvail ? 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]);

        if( isCtuCrossedByVirtualBoundaries && isProcessDisabled( x, y, numVerVirBndry, 0, verVirBndryPos, horVirBndryPos ) )

        {

          signLeft = -signRight;

          continue;

        }

        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 = &m_signLineBuf1->front();

    startY = isAboveAvail ? 0 : 1;

    endY   = isBelowAvail ? height : height-1;

    if (!isAboveAvail)

    {

      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]);

        if( isCtuCrossedByVirtualBoundaries && isProcessDisabled( x, y, 0, numHorVirBndry, verVirBndryPos, horVirBndryPos ) )

        {

          signUpLine[x] = -signDown;

          continue;

        }

        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  = &m_signLineBuf1->front();

    signDownLine= &m_signLineBuf2->front();

    startX = isLeftAvail ? 0 : 1 ;

    endX   = isRightAvail ? 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 = isAboveLeftAvail ? 0 : 1;

    firstLineEndX   = isAboveAvail? endX: 1;

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

    {

      if( isCtuCrossedByVirtualBoundaries && isProcessDisabled( x, 0, numVerVirBndry, numHorVirBndry, verVirBndryPos, horVirBndryPos ) )

      {

        continue;

      }

      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]);

        if (isCtuCrossedByVirtualBoundaries && isProcessDisabled(x, y, numVerVirBndry, numHorVirBndry, verVirBndryPos, horVirBndryPos))

        {

          signDownLine[x + 1] = -signDown;

          continue;

        }

        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 = isBelowAvail ? startX : (width -1);

    lastLineEndX   = isBelowRightAvail ? width : (width -1);

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

    {

      if (isCtuCrossedByVirtualBoundaries && isProcessDisabled(x, height - 1, numVerVirBndry, numHorVirBndry, verVirBndryPos, horVirBndryPos))

      {

        continue;

      }

      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 = &m_signLineBuf1->at(1);

    startX = isLeftAvail ? 0 : 1;

    endX   = isRightAvail ? 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 = isAboveAvail ? startX : (width -1 );

    firstLineEndX   = isAboveRightAvail ? width : (width-1);

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

    {

      if (isCtuCrossedByVirtualBoundaries && isProcessDisabled(x, 0, numVerVirBndry, numHorVirBndry, verVirBndryPos, horVirBndryPos))

      {

        continue;

      }

      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]);

        if( isCtuCrossedByVirtualBoundaries && isProcessDisabled( x, y, numVerVirBndry, numHorVirBndry, verVirBndryPos, horVirBndryPos ) )

        {

          signUpLine[x - 1] = -signDown;

          continue;

        }

        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 = isBelowLeftAvail ? 0 : 1;

    lastLineEndX   = isBelowAvail ? endX : 1;

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

    {

      if( isCtuCrossedByVirtualBoundaries && isProcessDisabled( x, height - 1, numVerVirBndry, numHorVirBndry, verVirBndryPos, horVirBndryPos ) )

      {

        continue;

      }

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

  }

  }

}

SampleAdaptiveOffset::~SampleAdaptiveOffset()

{

  destroy();

}

void SampleAdaptiveOffset::create( int picWidth, int picHeight, ChromaFormat format, uint32_t maxCUWidth, uint32_t maxCUHeight, uint32_t maxCUDepth, uint32_t bitShift, PelUnitBuf& unitBuf )

{

  offsetBlock = offsetBlock_core;

#if ENABLE_SIMD_OPT_SAO && defined( TARGET_SIMD_X86 )

  initSampleAdaptiveOffsetX86();

#endif

  m_tempBuf = unitBuf;

  //bit-depth related

  m_offsetStepLog2 = bitShift;

  m_numberOfComponents = getNumberValidComponents(format);

}

void SampleAdaptiveOffset::destroy()

{

}

#if 0

void SampleAdaptiveOffset::SAOProcess( CodingStructure& cs )

{

  const PreCalcValues& pcv = *cs.pcv;

  for( uint32_t yPos = 0; yPos < pcv.lumaHeight; yPos += pcv.maxCUHeight )

  {

    for( uint32_t xPos = 0; xPos < pcv.lumaWidth; xPos += pcv.maxCUWidth )

    {

      const uint32_t width  = (xPos + pcv.maxCUWidth  > pcv.lumaWidth)  ? (pcv.lumaWidth - xPos)  : pcv.maxCUWidth;

      const uint32_t height = (yPos + pcv.maxCUHeight > pcv.lumaHeight) ? (pcv.lumaHeight - yPos) : pcv.maxCUHeight;

      SAOProcessCTU( cs, UnitArea(cs.area.chromaFormat, Area(xPos , yPos, width, height)) );

    }

  }

  DTRACE_UPDATE(g_trace_ctx, (std::make_pair("poc", cs.slice->getPOC())));

  DTRACE_PIC_COMP(D_REC_CB_LUMA_SAO, cs, cs.getRecoBuf(), COMPONENT_Y);

  DTRACE_PIC_COMP(D_REC_CB_CHROMA_SAO, cs, cs.getRecoBuf(), COMPONENT_Cb);

  DTRACE_PIC_COMP(D_REC_CB_CHROMA_SAO, cs, cs.getRecoBuf(), COMPONENT_Cr);

  DTRACE    ( g_trace_ctx, D_CRC, "SAO" );

  DTRACE_CRC( g_trace_ctx, D_CRC, cs, cs.getRecoBuf() );

}

#endif

void SampleAdaptiveOffset::SAOPrepareCTULine( CodingStructure &cs, const UnitArea &lineArea )

{

  PROFILER_SCOPE_AND_STAGE( 1, g_timeProfiler, P_SAO );

  const PreCalcValues& pcv = *cs.pcv;

  PelUnitBuf           rec = cs.getRecoBuf();

  const int height = lineArea.lumaSize().height;

  const int y      = lineArea.lumaPos().y;

  const int cpyY       = y == 0 ? 0 : y + 2;

        int cpyHeight  = height;

            cpyHeight -= y == 0 ? 0 : 2;

            cpyHeight -= cpyY + cpyHeight >= pcv.lumaHeight ? 0 : 2;

            cpyHeight  = std::min<int>( cpyHeight, pcv.lumaHeight - cpyY );

  for( int x = 0; x < pcv.lumaWidth; x += pcv.maxCUWidth )

  {

    const int ctuRsAddr = getCtuAddr( Position( x, y ), *cs.pcv );

    SAOBlkParam* mergeList[NUM_SAO_MERGE_TYPES] = { nullptr, nullptr };

    getMergeList( cs, ctuRsAddr, mergeList );

    reconstructBlkSAOParam( cs.m_ctuData[ctuRsAddr].saoParam, mergeList );

  }

  const int numComp = getNumberValidComponents( pcv.chrFormat );

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

  {

    const ComponentID compID = ComponentID( i );

    const int currCpyY =   cpyY            >> getComponentScaleY( compID, pcv.chrFormat );

    const int currCpyH =   cpyHeight       >> getComponentScaleY( compID, pcv.chrFormat );

    const int currCtuW =   pcv.maxCUWidth  >> getComponentScaleX( compID, pcv.chrFormat );

    const int currPicW =   pcv.lumaWidth   >> getComponentScaleX( compID, pcv.chrFormat );

    const ptrdiff_t src_stride =       rec.bufs[ compID ].stride;

    const ptrdiff_t dst_stride = m_tempBuf.bufs[ compID ].stride;

    const Pel* src =       rec.bufs[ compID ].bufAt( 0, currCpyY );

          Pel* dst = m_tempBuf.bufs[ compID ].bufAt( 0, currCpyY );

    for( int j = currCpyY; j < ( currCpyY + currCpyH ); j++, src += src_stride, dst += dst_stride )

    {

      int numCpy   = 0;

      int cpyStart = 0;

      int ctuRsAddr = getCtuAddr( Position( 0, y ), *cs.pcv );

      for( int x = 0, currCpyX = 0; x <= pcv.widthInCtus; x++, currCpyX += currCtuW, ctuRsAddr++ )

      {

        if( x < pcv.widthInCtus && cs.m_ctuData[ctuRsAddr].saoParam[i].modeIdc != SAO_MODE_OFF )

        {

          if( !numCpy ) cpyStart = currCpyX - !!x;

          numCpy++;

        }

        else if( numCpy )

        {

          // copy

          int cpyLen = numCpy * currCtuW + !!cpyStart + 1;

          if( cpyStart + cpyLen > currPicW ) cpyLen = currPicW - cpyStart;

          memcpy( dst + cpyStart, src + cpyStart, cpyLen * sizeof( Pel ) );

          numCpy = 0;

        }

      }

    }

  }

  const int cpyY2      = cpyY + cpyHeight;

  const int cpyHeight2 = 4;

  if( cpyY2 < pcv.lumaHeight )

  {

    const UnitArea cpyLine2( pcv.chrFormat, Area( 0, cpyY2, pcv.lumaWidth, cpyHeight2 ) );

    m_tempBuf.subBuf( cpyLine2 ).copyFrom( rec.subBuf( cpyLine2 ) );

  }

}

void SampleAdaptiveOffset::SAOProcessCTULine( CodingStructure &cs, const UnitArea &lineArea )

{

  PROFILER_SCOPE_AND_STAGE( 1, g_timeProfiler, P_SAO );

  const PreCalcValues& pcv = *cs.pcv;

  PelUnitBuf           rec = cs.getRecoBuf();

  const int height         = lineArea.lumaSize().height;

  const int y              = lineArea.lumaPos().y;

  bool anySaoBlk = false;

  for( int x = 0; x < pcv.lumaWidth; x += pcv.maxCUWidth )

  {

    const int ctuRsAddr = getCtuAddr( Position( x, y ), *cs.pcv );

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

    {

      if( cs.m_ctuData[ctuRsAddr].saoParam[i].modeIdc != SAO_MODE_OFF )

      {

        anySaoBlk = true;

      }

    }

  }

  if( !anySaoBlk ) return;

  std::vector<int8_t> signLineBuf1;

  std::vector<int8_t> signLineBuf2;

  for( int x = 0; x < pcv.lumaWidth; x += pcv.maxCUWidth )

  {

    const int width = ( x + pcv.maxCUWidth > pcv.lumaWidth ) ? ( pcv.lumaWidth - x ) : pcv.maxCUWidth;

    const UnitArea ctuArea( pcv.chrFormat, Area( x, y, width, height ) );

    const int ctuRsAddr = getCtuAddr( ctuArea.lumaPos(), *cs.pcv );

    offsetCTU( ctuArea, m_tempBuf, rec, cs.m_ctuData[ctuRsAddr].saoParam, cs, signLineBuf1, signLineBuf2 );

  }

}

void SampleAdaptiveOffset::SAOProcessCTU( CodingStructure &cs, const UnitArea &ctuArea )

{

  PROFILER_SCOPE_AND_STAGE( 1, g_timeProfiler, P_SAO );

  PelUnitBuf           rec = cs.getRecoBuf();

  const int ctuRsAddr = getCtuAddr( ctuArea.lumaPos(), *cs.pcv );

  bool anySaoBlk = false;

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

  {

    if( cs.m_ctuData[ctuRsAddr].saoParam[i].modeIdc != SAO_MODE_OFF )

    {

      anySaoBlk = true;

    }

  }

  if( !anySaoBlk ) return;

  std::vector<int8_t> signLineBuf1;

  std::vector<int8_t> signLineBuf2;

  offsetCTU( ctuArea, m_tempBuf, rec, cs.m_ctuData[ctuRsAddr].saoParam, cs, signLineBuf1, signLineBuf2 );

}

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

{

  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);

    }

  }

  else //EO

  {

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

    {

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

    }

    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* mergeList[NUM_SAO_MERGE_TYPES])

{

  const PreCalcValues& pcv = *cs.pcv;

  const int ctuX       = ctuRsAddr % pcv.widthInCtus;

  const int ctuY       = ctuRsAddr / pcv.widthInCtus;

  const CodingUnit& cu = *cs.getCtuData( ctuRsAddr ).cuPtr[CH_L][0];

  int mergedCTUPos;

  int numValidMergeCandidates = 0;

  for( auto mergeType: { SAO_MERGE_LEFT, SAO_MERGE_ABOVE } )

  {

    SAOBlkParam* mergeCandidate = NULL;

    switch(mergeType)

    {

    case SAO_MERGE_ABOVE:

      if( ctuY > 0 )

      {

        mergedCTUPos = ctuRsAddr - pcv.widthInCtus;

        if( cu.above )

        {

          mergeCandidate = &( cs.m_ctuData[mergedCTUPos].saoParam );

        }

      }

      break;

    case SAO_MERGE_LEFT:

      if( ctuX > 0 )

      {

        mergedCTUPos = ctuRsAddr - 1;

        if( cu.left )

        {

          mergeCandidate = &( cs.m_ctuData[mergedCTUPos].saoParam );

        }

      }

      break;

    default:

      THROW_FATAL( "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

{

  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:

      {

        const SAOBlkParam* mergeTarget = mergeList[offsetParam.typeIdc];

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

        offsetParam = (*mergeTarget)[component];

      }

      break;

    default:

      {

        THROW_RECOVERABLE( "Not a supported mode" );

      }

    }

  }

}

void SampleAdaptiveOffset::offsetCTU( const UnitArea& area, const CPelUnitBuf& src, PelUnitBuf& res, SAOBlkParam& saoblkParam, CodingStructure& cs, std::vector<int8_t> &signLineBuf1, std::vector<int8_t> &signLineBuf2 )

{

  const uint32_t numberOfComponents = getNumberValidComponents( area.chromaFormat );

  if( std::all_of( &saoblkParam[0],

                   &saoblkParam[numberOfComponents],

                   [](const SAOOffset & p){ return p.modeIdc == SAO_MODE_OFF; } ) )

  {

    return;

  }

  bool isLeftAvail, isRightAvail, isAboveAvail, isBelowAvail, isAboveLeftAvail, isAboveRightAvail, isBelowLeftAvail, isBelowRightAvail;

  // block boundary availability

  deriveLoopFilterBoundaryAvailibility( cs, area.Y(), isLeftAvail, isRightAvail, isAboveAvail, isBelowAvail, isAboveLeftAvail, isAboveRightAvail, isBelowLeftAvail, isBelowRightAvail );

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

  if (signLineBuf1.size() < lineBufferSize)

  {

    signLineBuf1.resize(lineBufferSize);

    signLineBuf2.resize(lineBufferSize);

  }

  int  numHorVirBndry       = 0;

  int  numVerVirBndry       = 0;

  int  horVirBndryPos[]     = { -1, -1, -1 };

  int  verVirBndryPos[]     = { -1, -1, -1 };

  int  horVirBndryPosComp[] = { -1, -1, -1 };

  int  verVirBndryPosComp[] = { -1, -1, -1 };

  bool isCtuCrossedByVirtualBoundaries = isCrossedByVirtualBoundaries( cs.picHeader.get(),

                                                                       area.Y(),

                                                                       numHorVirBndry, numVerVirBndry,

                                                                       horVirBndryPos, verVirBndryPos );

  if( isCtuCrossedByVirtualBoundaries )

  {

    CHECK( numHorVirBndry >= (int)( sizeof(horVirBndryPos) / sizeof(horVirBndryPos[0]) ), "Too many virtual boundaries" );

    CHECK( numHorVirBndry >= (int)( sizeof(verVirBndryPos) / sizeof(verVirBndryPos[0]) ), "Too many virtual boundaries" );

  }

  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)

    {

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

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

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

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

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

      {

        horVirBndryPosComp[i] = (horVirBndryPos[i] >> getComponentScaleY(compID, area.chromaFormat)) - compArea.y;

      }

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

      {

        verVirBndryPosComp[i] = (verVirBndryPos[i] >> getComponentScaleX(compID, area.chromaFormat)) - compArea.x;

      }

      offsetBlock( cs.sps->getBitDepth(),

                   cs.getCtuData(cs.ctuRsAddr(area.Y().pos(), CH_L)).cuPtr[0][0]->slice->clpRng(compID),

                   ctbOffset.typeIdc, ctbOffset.offset,ctbOffset.typeAuxInfo

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

                  , isLeftAvail, isRightAvail

                  , isAboveAvail, isBelowAvail

                  , isAboveLeftAvail, isAboveRightAvail

                  , isBelowLeftAvail, isBelowRightAvail

                  , &signLineBuf1

                  , &signLineBuf2

                  , isCtuCrossedByVirtualBoundaries

                  , horVirBndryPosComp

                  , verVirBndryPosComp

                  , numHorVirBndry

                  , numVerVirBndry

                  );

    }

  } //compIdx

}

void SampleAdaptiveOffset::deriveLoopFilterBoundaryAvailibility( CodingStructure& cs,

                                                                 const Position&  pos,

                                                                 bool&            isLeftAvail,

                                                                 bool&            isRightAvail,

                                                                 bool&            isAboveAvail,

                                                                 bool&            isBelowAvail,

                                                                 bool&            isAboveLeftAvail,

                                                                 bool&            isAboveRightAvail,

                                                                 bool&            isBelowLeftAvail,

                                                                 bool&            isBelowRightAvail ) const

{

  const int ctusz  = cs.pcv->maxCUWidth;

  const int ctuX   = pos.x / ctusz;

  const int ctuY   = pos.y / ctusz;

  const int width  = cs.pcv->widthInCtus;

  const int height = cs.pcv->heightInCtus;

  const CodingUnit* cuCurr        =                       cs.getCtuData( ctuX,     ctuY     ).cuPtr[0][0];

  const CodingUnit* cuLeft        = ctuX     > 0        ? cs.getCtuData( ctuX - 1, ctuY     ).cuPtr[0][0] : nullptr;

  const CodingUnit* cuRight       = ctuX + 1 < width    ? cs.getCtuData( ctuX + 1, ctuY     ).cuPtr[0][0] : nullptr;

  const CodingUnit* cuAbove       = ctuY     > 0        ? cs.getCtuData( ctuX,     ctuY - 1 ).cuPtr[0][0] : nullptr;

  const CodingUnit* cuBelow       = ctuY + 1 < height   ? cs.getCtuData( ctuX,     ctuY + 1 ).cuPtr[0][0] : nullptr;

  const CodingUnit* cuAboveLeft   = cuLeft  && cuAbove  ? cs.getCtuData( ctuX - 1, ctuY - 1 ).cuPtr[0][0] : nullptr;

  const CodingUnit* cuAboveRight  = cuRight && cuAbove  ? cs.getCtuData( ctuX + 1, ctuY - 1 ).cuPtr[0][0] : nullptr;

  const CodingUnit* cuBelowLeft   = cuLeft  && cuBelow  ? cs.getCtuData( ctuX - 1, ctuY + 1 ).cuPtr[0][0] : nullptr;

  const CodingUnit* cuBelowRight  = cuRight && cuBelow  ? cs.getCtuData( ctuX + 1, ctuY + 1 ).cuPtr[0][0] : nullptr;

  isLeftAvail       = (cuLeft       != NULL);

  isAboveAvail      = (cuAbove      != NULL);

  isRightAvail      = (cuRight      != NULL);

  isBelowAvail      = (cuBelow      != NULL);

  isAboveLeftAvail  = (cuAboveLeft  != NULL);

  isAboveRightAvail = (cuAboveRight != NULL);

  isBelowLeftAvail  = (cuBelowLeft  != NULL);

  isBelowRightAvail = (cuBelowRight != NULL);

  // check cross slice flags

  const bool isLoopFilterAcrossSlicePPS = cs.pps->getLoopFilterAcrossSlicesEnabledFlag();

  if (!isLoopFilterAcrossSlicePPS)

  {

    isLeftAvail       = isLeftAvail       && CU::isSameSlice(*cuCurr, *cuLeft);

    isAboveAvail      = isAboveAvail      && CU::isSameSlice(*cuCurr, *cuAbove);

    isRightAvail      = isRightAvail      && CU::isSameSlice(*cuCurr, *cuRight);

    isBelowAvail      = isBelowAvail      && CU::isSameSlice(*cuCurr, *cuBelow);

    isAboveLeftAvail  = isAboveLeftAvail  && CU::isSameSlice(*cuCurr, *cuAboveLeft);

    isAboveRightAvail = isAboveRightAvail && CU::isSameSlice(*cuCurr, *cuAboveRight);

    isBelowLeftAvail  = isBelowLeftAvail  && CU::isSameSlice(*cuCurr, *cuBelowLeft);

    isBelowRightAvail = isBelowRightAvail && CU::isSameSlice(*cuCurr, *cuBelowRight);

  }

  // check cross tile flags

  const bool isLoopFilterAcrossTilePPS = cs.pps->getLoopFilterAcrossTilesEnabledFlag();

  if (!isLoopFilterAcrossTilePPS)

  {

    isLeftAvail       = isLeftAvail       && CU::isSameTile(*cuCurr, *cuLeft);

    isAboveAvail      = isAboveAvail      && CU::isSameTile(*cuCurr, *cuAbove);

    isRightAvail      = isRightAvail      && CU::isSameTile(*cuCurr, *cuRight);

    isBelowAvail      = isBelowAvail      && CU::isSameTile(*cuCurr, *cuBelow);

    isAboveLeftAvail  = isAboveLeftAvail  && CU::isSameTile(*cuCurr, *cuAboveLeft);

    isAboveRightAvail = isAboveRightAvail && CU::isSameTile(*cuCurr, *cuAboveRight);

    isBelowLeftAvail  = isBelowLeftAvail  && CU::isSameTile(*cuCurr, *cuBelowLeft);

    isBelowRightAvail = isBelowRightAvail && CU::isSameTile(*cuCurr, *cuBelowRight);

  }

  // check cross subpic flags

  if( cs.sps->getSubPicInfoPresentFlag() )

  {

    const SubPic& curSubPic = cs.pps->getSubPicFromCU(*cuCurr);

    if( !curSubPic.getloopFilterAcrossSubPicEnabledFlag() )

    {

      isLeftAvail       = isLeftAvail       && CU::isSameSubPic(*cuCurr, *cuLeft);

      isAboveAvail      = isAboveAvail      && CU::isSameSubPic(*cuCurr, *cuAbove);

      isRightAvail      = isRightAvail      && CU::isSameSubPic(*cuCurr, *cuRight);

      isBelowAvail      = isBelowAvail      && CU::isSameSubPic(*cuCurr, *cuBelow);

      isAboveLeftAvail  = isAboveLeftAvail  && CU::isSameSubPic(*cuCurr, *cuAboveLeft);

      isAboveRightAvail = isAboveRightAvail && CU::isSameSubPic(*cuCurr, *cuAboveRight);

      isBelowLeftAvail  = isBelowLeftAvail  && CU::isSameSubPic(*cuCurr, *cuBelowLeft);

      isBelowRightAvail = isBelowRightAvail && CU::isSameSubPic(*cuCurr, *cuBelowRight);

    }

  }

}

bool SampleAdaptiveOffset::isProcessDisabled( int xPos, int yPos, int numVerVirBndry, int numHorVirBndry, int verVirBndryPos[], int horVirBndryPos[] )

{

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

  {

    if ((xPos == verVirBndryPos[i]) || (xPos == verVirBndryPos[i] - 1))

    {

      return true;

    }

  }

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

  {

    if ((yPos == horVirBndryPos[i]) || (yPos == horVirBndryPos[i] - 1))

    {

      return true;

    }

  }

  return false;

}

}