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/**

 \file     EncSampleAdaptiveOffset.cpp

 \brief       estimation part of sample adaptive offset class

 */

#include "EncSampleAdaptiveOffset.h"

#include "CommonLib/UnitTools.h"

#include "CommonLib/dtrace_codingstruct.h"

#include "CommonLib/dtrace_buffer.h"

#include "CommonLib/CodingStructure.h"

#include <string.h>

#include <stdlib.h>

#include <math.h>

#include "vvenc/vvencCfg.h"

//! \ingroup EncoderLib

//! \{

namespace vvenc {

#define SAOCtx(c) SubCtx( Ctx::Sao, c )

//! rounding with IBDI

inline double xRoundIbdi2(int bitDepth, double x)

{

  return ((x) >= 0 ? ((int)((x) + 0.5)) : ((int)((x) -0.5)));

}

inline double xRoundIbdi(int bitDepth, double x)

{

  return (bitDepth > 8 ? xRoundIbdi2(bitDepth, (x)) : ((x)>=0 ? ((int)((x)+0.5)) : ((int)((x)-0.5)))) ;

}

EncSampleAdaptiveOffset::EncSampleAdaptiveOffset()

  : m_CABACEstimator( nullptr )

  , m_CtxCache      ( nullptr )

{

}

EncSampleAdaptiveOffset::~EncSampleAdaptiveOffset()

{

}

void EncSampleAdaptiveOffset::init( const VVEncCfg& encCfg )

{

  m_EncCfg = &encCfg;

  if ( encCfg.m_bUseSAO )

  {

    SampleAdaptiveOffset::init( encCfg.m_internChromaFormat, encCfg.m_CTUSize, encCfg.m_CTUSize, encCfg.m_log2SaoOffsetScale[CH_L], encCfg.m_log2SaoOffsetScale[CH_C] );

  }

}

void EncSampleAdaptiveOffset::initSlice( const Slice* slice )

{

  memcpy( m_lambda, slice->getLambdas(), sizeof( m_lambda ) );

}

void EncSampleAdaptiveOffset::setCtuEncRsrc( CABACWriter* cabacEstimator, CtxCache* ctxCache )

{

  m_CABACEstimator = cabacEstimator;

  m_CtxCache       = ctxCache;

}

void EncSampleAdaptiveOffset::disabledRate( CodingStructure& cs, double saoDisabledRate[ MAX_NUM_COMP ][ VVENC_MAX_TLAYER ], SAOBlkParam* reconParams, const double saoEncodingRate, const double saoEncodingRateChroma, const ChromaFormat& chromaFormat )

{

  if ( saoEncodingRate > 0.0 )

  {

    const PreCalcValues& pcv     = *cs.pcv;

    const int numberOfComponents = getNumberValidComponents( chromaFormat );

    const int picTempLayer       = cs.slice->TLayer;

    int numCtusForSAOOff[MAX_NUM_COMP];

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

    {

      numCtusForSAOOff[compIdx] = 0;

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

      {

        if( reconParams[ctuRsAddr][compIdx].modeIdc == SAO_MODE_OFF)

        {

          numCtusForSAOOff[compIdx]++;

        }

      }

    }

    if (saoEncodingRateChroma > 0.0)

    {

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

      {

        saoDisabledRate[compIdx][picTempLayer] = (double)numCtusForSAOOff[compIdx]/(double)pcv.sizeInCtus;

      }

    }

    else if (picTempLayer == 0)

    {

      saoDisabledRate[COMP_Y][0] = (double)(numCtusForSAOOff[COMP_Y]+numCtusForSAOOff[COMP_Cb]+numCtusForSAOOff[COMP_Cr])/(double)(pcv.sizeInCtus *3);

    }

  }

}

void EncSampleAdaptiveOffset::decidePicParams( const CodingStructure& cs, double saoDisabledRate[ MAX_NUM_COMP ][ VVENC_MAX_TLAYER ], bool saoEnabled[ MAX_NUM_COMP ], const double saoEncodingRate, const double saoEncodingRateChroma, const ChromaFormat& chromaFormat )

{

  const Slice& slice           = *cs.slice;

  const int numberOfComponents = getNumberValidComponents( chromaFormat );

  // reset

  if( slice.pendingRasInit )

  {

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

    {

      for( int tempLayer = 1; tempLayer < VVENC_MAX_TLAYER; tempLayer++ )

      {

        saoDisabledRate[ compIdx ][ tempLayer ] = 0.0;

      }

    }

  }

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

  {

    saoEnabled[ compIdx ] = false;

  }

  const int picTempLayer = slice.TLayer;

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

  {

    // enable per default

    saoEnabled[ compIdx ] = true;

    if( saoEncodingRate > 0.0 )

    {

      if( saoEncodingRateChroma > 0.0 )

      {

        // decide slice-level on/off based on previous results

        if( ( picTempLayer > 0 )

          && ( saoDisabledRate[ compIdx ][ picTempLayer - 1 ] > ( ( compIdx == COMP_Y ) ? saoEncodingRate : saoEncodingRateChroma ) ) )

        {

          saoEnabled[ compIdx ] = false;

        }

      }

      else

      {

        // decide slice-level on/off based on previous results

        if( ( picTempLayer > 0 )

          && ( saoDisabledRate[ COMP_Y ][ 0 ] > saoEncodingRate ) )

        {

          saoEnabled[ compIdx ] = false;

        }

      }

    }

  }

}

void EncSampleAdaptiveOffset::storeCtuReco( CodingStructure& cs, const UnitArea& ctuArea, const int ctuX, const int ctuY )

{

  const int STORE_CTU_INCREASE = 8;

  Position lPos( ctuArea.lx() + STORE_CTU_INCREASE, ctuArea.ly() + STORE_CTU_INCREASE );

  Size    lSize( ctuArea.lwidth(), ctuArea.lheight() );

  const bool tileBdryClip = cs.pps->getNumTiles() > 1 && !cs.pps->loopFilterAcrossTilesEnabled;

  int startX = 0;

  int startY = 0;

  if( tileBdryClip )  

  {

    startX = cs.pps->tileColBd[cs.pps->ctuToTileCol[ctuX]] << cs.pcv->maxCUSizeLog2;

    startY = cs.pps->tileRowBd[cs.pps->ctuToTileRow[ctuY]] << cs.pcv->maxCUSizeLog2;

  }

  if ( ctuArea.lx() == startX )

  {

    lPos.x       = ctuArea.lx();

    lSize.width += STORE_CTU_INCREASE;

  }

  if ( ctuArea.ly() == startY )

  {

    lPos.y        = ctuArea.ly();

    lSize.height += STORE_CTU_INCREASE;

  }

  int clipX = cs.pcv->lumaWidth  - lPos.x;

  int clipY = cs.pcv->lumaHeight - lPos.y;

  if( tileBdryClip )  

  {

    clipX  = cs.pps->tileColBdRgt[cs.pps->ctuToTileCol[ctuX]] - lPos.x;

    clipY  = cs.pps->tileRowBdBot[cs.pps->ctuToTileRow[ctuY]] - lPos.y;

  }

  lSize.clipSize( clipX, clipY );

  const UnitArea relocArea( ctuArea.chromaFormat, Area( lPos, lSize ) );

  Picture& pic       = *cs.picture;

  PelUnitBuf recoYuv = pic.getRecoBuf().subBuf( relocArea );

  PelUnitBuf tempYuv = pic.getSaoBuf().subBuf( relocArea );

  tempYuv.copyFrom( recoYuv );

}

void EncSampleAdaptiveOffset::getCtuStatistics( CodingStructure& cs, std::vector<SAOStatData**>& saoStatistics, const UnitArea& ctuArea, const int ctuRsAddr )

{

  const PreCalcValues& pcv     = *cs.pcv;

  const int numberOfComponents = getNumberValidComponents( pcv.chrFormat );

  bool isLeftAvail             = false;

  bool isRightAvail            = false;

  bool isAboveAvail            = false;

  bool isBelowAvail            = false;

  bool isAboveLeftAvail        = false;

  bool isAboveRightAvail       = false;

  deriveLoopFilterBoundaryAvailibility( cs, ctuArea.Y(), isLeftAvail, isAboveAvail, isAboveLeftAvail );

  // NOTE: The number of skipped lines during gathering CTU statistics depends on the slice boundary availabilities.

  // For simplicity, here only picture boundaries are considered.

  isRightAvail      = ( ctuArea.Y().x + pcv.maxCUSize < pcv.lumaWidth  );

  isBelowAvail      = ( ctuArea.Y().y + pcv.maxCUSize < pcv.lumaHeight );

  isAboveRightAvail = ( ( ctuArea.Y().y > 0 ) && ( isRightAvail ) );

  CHECK( !cs.pps->loopFilterAcrossSlicesEnabled, "Not implemented" );

  if( cs.pps->getNumTiles() > 1 && !cs.pps->loopFilterAcrossTilesEnabled )

  {

    const int ctuX    = ctuArea.lx() >> cs.pcv->maxCUSizeLog2;

    const int ctuY    = ctuArea.ly() >> cs.pcv->maxCUSizeLog2;

    isRightAvail      = isRightAvail      && cs.pps->canFilterCtuBdry( ctuX, ctuY,  1, 0 );

    isBelowAvail      = isBelowAvail      && cs.pps->canFilterCtuBdry( ctuX, ctuY,  0, 1 );

    isAboveRightAvail = isAboveRightAvail && cs.pps->canFilterCtuBdry( ctuX, ctuY,  1,-1 );

  }

  //VirtualBoundaries vb;

  //bool isCtuCrossedByVirtualBoundaries = vb.isCrossedByVirtualBoundaries(xPos, yPos, width, height, cs.slice->pps);

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

  {

    const ComponentID compID = ComponentID( compIdx );

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

    PelBuf srcBuf = cs.picture->getSaoBuf().get( compID );

    PelBuf orgBuf = cs.picture->getOrigBuf().get( compID );

    getBlkStats( compID,

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

                 saoStatistics[ ctuRsAddr ][ compID ],

                 srcBuf.bufAt( compArea ),

                 orgBuf.bufAt( compArea ),

                 srcBuf.stride,

                 orgBuf.stride,

                 compArea.width,

                 compArea.height,

                 isLeftAvail, isRightAvail, isAboveAvail, isBelowAvail, isAboveLeftAvail, isAboveRightAvail

               );

  }

}

void EncSampleAdaptiveOffset::getStatistics(std::vector<SAOStatData**>& blkStats, PelUnitBuf& orgYuv, PelUnitBuf& srcYuv, CodingStructure& cs )

{

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

  const PreCalcValues& pcv = *cs.pcv;

  const int numberOfComponents = getNumberValidComponents(pcv.chrFormat);

  size_t lineBufferSize = pcv.maxCUSize + 1;

  if (m_signLineBuf1.size() != lineBufferSize)

  {

    m_signLineBuf1.resize(lineBufferSize);

    m_signLineBuf2.resize(lineBufferSize);

  }

  int ctuRsAddr = 0;

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

  {

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

    {

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

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

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

      deriveLoopFilterBoundaryAvailibility(cs, area.Y(), isLeftAvail, isAboveAvail, isAboveLeftAvail );

      //NOTE: The number of skipped lines during gathering CTU statistics depends on the slice boundary availabilities.

      //For simplicity, here only picture boundaries are considered.

      isRightAvail      = (xPos + pcv.maxCUSize  < pcv.lumaWidth );

      isBelowAvail      = (yPos + pcv.maxCUSize < pcv.lumaHeight);

      isAboveRightAvail = ((yPos > 0) && (isRightAvail));

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

      {

        const ComponentID compID = ComponentID(compIdx);

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

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

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

        int  orgStride  = orgYuv.get(compID).stride;

        Pel* orgBlk     = orgYuv.get(compID).bufAt( compArea );

        getBlkStats(compID, cs.sps->bitDepths[toChannelType(compID)], blkStats[ctuRsAddr][compID]

                  , srcBlk, orgBlk, srcStride, orgStride, compArea.width, compArea.height

                  , isLeftAvail,  isRightAvail, isAboveAvail, isBelowAvail, isAboveLeftAvail, isAboveRightAvail );

      }

      ctuRsAddr++;

    }

  }

}

void EncSampleAdaptiveOffset::decideCtuParams( CodingStructure& cs, const std::vector<SAOStatData**>& saoStatistics, const bool saoEnabled[ MAX_NUM_COMP ], const bool allBlksDisabled, const UnitArea& ctuArea, const int ctuRsAddr, SAOBlkParam* reconParams, SAOBlkParam* codedParams )

{

  const PreCalcValues& pcv = *cs.pcv;

  const Slice& slice       = *cs.slice;

  const int  ctuPosX       = ctuRsAddr % pcv.widthInCtus;

  const int  ctuPosY       = ctuRsAddr / pcv.widthInCtus;

  // reset CABAC estimator

  if( m_EncCfg->m_ensureWppBitEqual

      && m_EncCfg->m_numThreads < 1

      && ctuPosX == 0

      && ctuPosY > 0 )

  {

    m_CABACEstimator->initCtxModels( slice );

  }

  // check disabled

  if( allBlksDisabled )

  {

    codedParams[ ctuRsAddr ].reset();

    return;

  }

  // get merge list

  SAOBlkParam* mergeList[ NUM_SAO_MERGE_TYPES ] = { NULL };

  getMergeList( cs, ctuRsAddr, reconParams, mergeList );

  const TempCtx ctxStart( m_CtxCache, SAOCtx( m_CABACEstimator->getCtx() ) );

  TempCtx       ctxBest ( m_CtxCache );

  SAOBlkParam modeParam;

  double minCost  = MAX_DOUBLE;

  double modeCost = MAX_DOUBLE;

  for( int mode = 1; mode < NUM_SAO_MODES; mode++ )

  {

    if( mode > 1 )

    {

      m_CABACEstimator->getCtx() = SAOCtx( ctxStart );

    }

    switch( mode )

    {

    case SAO_MODE_NEW:

      {

        deriveModeNewRDO( cs.sps->bitDepths, ctuRsAddr, mergeList, saoEnabled, saoStatistics, modeParam, modeCost );

      }

      break;

    case SAO_MODE_MERGE:

      {

        deriveModeMergeRDO( cs.sps->bitDepths, ctuRsAddr, mergeList, saoEnabled, saoStatistics, modeParam, modeCost );

      }

      break;

    default:

      {

        THROW( "Not a supported SAO mode." );

      }

    }

    if( modeCost < minCost )

    {

      minCost                  = modeCost;

      codedParams[ ctuRsAddr ] = modeParam;

      ctxBest                  = SAOCtx( m_CABACEstimator->getCtx() );

    }

  }

  // apply reconstructed offsets

  m_CABACEstimator->getCtx() = SAOCtx( ctxBest );

  reconParams[ ctuRsAddr ] = codedParams[ ctuRsAddr ];

  reconstructBlkSAOParam( reconParams[ ctuRsAddr ], mergeList );

  Picture& pic = *cs.picture;

  offsetCTU( ctuArea, pic.getSaoBuf(), cs.getRecoBuf(), reconParams[ ctuRsAddr ], cs );

}

int64_t EncSampleAdaptiveOffset::getDistortion(const int channelBitDepth, int typeIdc, int typeAuxInfo, int* invQuantOffset, SAOStatData& statData)

{

  int64_t dist        = 0;

  int shift = 2 * DISTORTION_PRECISION_ADJUSTMENT(channelBitDepth);

  switch(typeIdc)

  {

  case SAO_TYPE_EO_0:

  case SAO_TYPE_EO_90:

  case SAO_TYPE_EO_135:

  case SAO_TYPE_EO_45:

    {

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

      {

        dist += estSaoDist( statData.count[offsetIdx], invQuantOffset[offsetIdx], statData.diff[offsetIdx], shift);

      }

    }

    break;

  case SAO_TYPE_BO:

    {

      for (int offsetIdx=typeAuxInfo; offsetIdx<typeAuxInfo+4; offsetIdx++)

      {

        int bandIdx = offsetIdx % NUM_SAO_BO_CLASSES ;

        dist += estSaoDist( statData.count[bandIdx], invQuantOffset[bandIdx], statData.diff[bandIdx], shift);

      }

    }

    break;

  default:

    {

      THROW("Not a supported type");

    }

  }

  return dist;

}

inline int64_t EncSampleAdaptiveOffset::estSaoDist(int64_t count, int64_t offset, int64_t diffSum, int shift)

{

  return (( count*offset*offset-diffSum*offset*2 ) >> shift);

}

inline int EncSampleAdaptiveOffset::estIterOffset(int typeIdx, double lambda, int offsetInput, int64_t count, int64_t diffSum, int shift, int bitIncrease, int64_t& bestDist, double& bestCost, int offsetTh )

{

  int iterOffset, tempOffset;

  int64_t tempDist, tempRate;

  double tempCost, tempMinCost;

  int offsetOutput = 0;

  iterOffset = offsetInput;

  // Assuming sending quantized value 0 results in zero offset and sending the value zero needs 1 bit. entropy coder can be used to measure the exact rate here.

  tempMinCost = lambda;

  while (iterOffset != 0)

  {

    // Calculate the bits required for signaling the offset

    tempRate = (typeIdx == SAO_TYPE_BO) ? (abs((int)iterOffset)+2) : (abs((int)iterOffset)+1);

    if (abs((int)iterOffset)==offsetTh) //inclusive

    {

      tempRate --;

    }

    // Do the dequantization before distortion calculation

    tempOffset  = iterOffset * (1<< bitIncrease);

    tempDist    = estSaoDist( count, tempOffset, diffSum, shift);

    tempCost    = ((double)tempDist + lambda * (double) tempRate);

    if(tempCost < tempMinCost)

    {

      tempMinCost = tempCost;

      offsetOutput = iterOffset;

      bestDist = tempDist;

      bestCost = tempCost;

    }

    iterOffset = (iterOffset > 0) ? (iterOffset-1):(iterOffset+1);

  }

  return offsetOutput;

}

void EncSampleAdaptiveOffset::deriveOffsets(ComponentID compIdx, const int channelBitDepth, int typeIdc, SAOStatData& statData, int* quantOffsets, int& typeAuxInfo)

{

  int bitDepth = channelBitDepth;

  int shift = 2 * DISTORTION_PRECISION_ADJUSTMENT(bitDepth);

  int offsetTh = SampleAdaptiveOffset::getMaxOffsetQVal(channelBitDepth);  //inclusive

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

  //derive initial offsets

  int numClasses = (typeIdc == SAO_TYPE_BO)?((int)NUM_SAO_BO_CLASSES):((int)NUM_SAO_EO_CLASSES);

  for(int classIdx=0; classIdx< numClasses; classIdx++)

  {

    if( (typeIdc != SAO_TYPE_BO) && (classIdx==SAO_CLASS_EO_PLAIN)  )

    {

      continue; //offset will be zero

    }

    if(statData.count[classIdx] == 0)

    {

      continue; //offset will be zero

    }

#if (  DISTORTION_PRECISION_ADJUSTMENT(x)  == 0 )

    quantOffsets[classIdx] =

       (int) xRoundIbdi(bitDepth, (double)(statData.diff[classIdx] ) / (double)(statData.count[classIdx] << m_offsetStepLog2[compIdx]));

     quantOffsets[classIdx] = Clip3(-offsetTh, offsetTh, quantOffsets[classIdx]);

#else

      quantOffsets[classIdx] =

        (int) xRoundIbdi(bitDepth, (double)(statData.diff[classIdx] << DISTORTION_PRECISION_ADJUSTMENT(bitDepth))

                                     / (double)(statData.count[classIdx] << m_offsetStepLog2[compIdx]));

      quantOffsets[classIdx] = Clip3(-offsetTh, offsetTh, quantOffsets[classIdx]);

#endif

  }

  // adjust offsets

  switch(typeIdc)

  {

  case SAO_TYPE_EO_0:

  case SAO_TYPE_EO_90:

  case SAO_TYPE_EO_135:

  case SAO_TYPE_EO_45:

    {

      int64_t classDist;

      double classCost;

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

      {

        if(classIdx==SAO_CLASS_EO_FULL_VALLEY && quantOffsets[classIdx] < 0)

        {

          quantOffsets[classIdx] =0;

        }

        if(classIdx==SAO_CLASS_EO_HALF_VALLEY && quantOffsets[classIdx] < 0)

        {

          quantOffsets[classIdx] =0;

        }

        if(classIdx==SAO_CLASS_EO_HALF_PEAK   && quantOffsets[classIdx] > 0)

        {

          quantOffsets[classIdx] =0;

        }

        if(classIdx==SAO_CLASS_EO_FULL_PEAK   && quantOffsets[classIdx] > 0)

        {

          quantOffsets[classIdx] =0;

        }

        if( quantOffsets[classIdx] != 0 ) //iterative adjustment only when derived offset is not zero

        {

          quantOffsets[classIdx] = estIterOffset( typeIdc, m_lambda[compIdx], quantOffsets[classIdx], statData.count[classIdx], statData.diff[classIdx], shift, m_offsetStepLog2[compIdx], classDist , classCost , offsetTh );

        }

      }

      typeAuxInfo =0;

    }

    break;

  case SAO_TYPE_BO:

    {

      int64_t  distBOClasses[NUM_SAO_BO_CLASSES];

      double costBOClasses[NUM_SAO_BO_CLASSES];

      ::memset(distBOClasses, 0, sizeof(int64_t)*NUM_SAO_BO_CLASSES);

      for(int classIdx=0; classIdx< NUM_SAO_BO_CLASSES; classIdx++)

      {

        costBOClasses[classIdx]= m_lambda[compIdx];

        if( quantOffsets[classIdx] != 0 ) //iterative adjustment only when derived offset is not zero

        {

          quantOffsets[classIdx] = estIterOffset( typeIdc, m_lambda[compIdx], quantOffsets[classIdx], statData.count[classIdx], statData.diff[classIdx], shift, m_offsetStepLog2[compIdx], distBOClasses[classIdx], costBOClasses[classIdx], offsetTh );

        }

      }

      //decide the starting band index

      double minCost = MAX_DOUBLE, cost;

      for(int band=0; band< NUM_SAO_BO_CLASSES; band++)

      {

        cost  = costBOClasses[(band  )%NUM_SAO_BO_CLASSES];

        cost += costBOClasses[(band+1)%NUM_SAO_BO_CLASSES];

        cost += costBOClasses[(band+2)%NUM_SAO_BO_CLASSES];

        cost += costBOClasses[(band+3)%NUM_SAO_BO_CLASSES];

        if(cost < minCost)

        {

          minCost = cost;

          typeAuxInfo = band;

        }

      }

      //clear those unused classes

      int clearQuantOffset[NUM_SAO_BO_CLASSES];

      ::memset(clearQuantOffset, 0, sizeof(int)*NUM_SAO_BO_CLASSES);

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

      {

        int band = (typeAuxInfo+i)%NUM_SAO_BO_CLASSES;

        clearQuantOffset[band] = quantOffsets[band];

      }

      ::memcpy(quantOffsets, clearQuantOffset, sizeof(int)*NUM_SAO_BO_CLASSES);

    }

    break;

  default:

    {

      THROW("Not a supported type");

    }

  }

}

void EncSampleAdaptiveOffset::deriveModeNewRDO(const BitDepths &bitDepths, int ctuRsAddr, SAOBlkParam* mergeList[NUM_SAO_MERGE_TYPES], const bool* sliceEnabled, const std::vector<SAOStatData**>& blkStats, SAOBlkParam& modeParam, double& modeNormCost )

{

  double minCost, cost;

  uint64_t previousFracBits;

  const int numberOfComponents = m_numberOfComponents;

  int64_t dist[MAX_NUM_COMP], modeDist[MAX_NUM_COMP];

  SAOOffset testOffset[MAX_NUM_COMP];

  int invQuantOffset[MAX_NUM_SAO_CLASSES];

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

  {

    modeDist[comp] = 0;

  }

  //pre-encode merge flags

  modeParam[COMP_Y].modeIdc = SAO_MODE_OFF;

  const TempCtx ctxStartBlk   ( m_CtxCache, SAOCtx( m_CABACEstimator->getCtx() ) );

  m_CABACEstimator->sao_block_pars( modeParam, bitDepths, sliceEnabled, (mergeList[SAO_MERGE_LEFT]!= NULL), (mergeList[SAO_MERGE_ABOVE]!= NULL), true );

  const TempCtx ctxStartLuma  ( m_CtxCache, SAOCtx( m_CABACEstimator->getCtx() ) );

  TempCtx       ctxBestLuma   ( m_CtxCache );

    //------ luma --------//

  {

    const ComponentID compIdx = COMP_Y;

    //"off" case as initial cost

    modeParam[compIdx].modeIdc = SAO_MODE_OFF;

    m_CABACEstimator->resetBits();

    m_CABACEstimator->sao_offset_pars( modeParam[compIdx], compIdx, sliceEnabled[compIdx], bitDepths[CH_L] );

    modeDist[compIdx] = 0;

    minCost           = m_lambda[compIdx] * (FRAC_BITS_SCALE * m_CABACEstimator->getEstFracBits());

    ctxBestLuma = SAOCtx( m_CABACEstimator->getCtx() );

    if(sliceEnabled[compIdx])

    {

      for(int typeIdc=0; typeIdc< NUM_SAO_NEW_TYPES; typeIdc++)

      {

        testOffset[compIdx].modeIdc = SAO_MODE_NEW;

        testOffset[compIdx].typeIdc = typeIdc;

        //derive coded offset

        deriveOffsets(compIdx, bitDepths[CH_L], typeIdc, blkStats[ctuRsAddr][compIdx][typeIdc], testOffset[compIdx].offset, testOffset[compIdx].typeAuxInfo);

        //inversed quantized offsets

        invertQuantOffsets(compIdx, typeIdc, testOffset[compIdx].typeAuxInfo, invQuantOffset, testOffset[compIdx].offset);

        //get distortion

        dist[compIdx] = getDistortion(bitDepths[CH_L], testOffset[compIdx].typeIdc, testOffset[compIdx].typeAuxInfo, invQuantOffset, blkStats[ctuRsAddr][compIdx][typeIdc]);

        //get rate

        m_CABACEstimator->getCtx() = SAOCtx( ctxStartLuma );

        m_CABACEstimator->resetBits();

        m_CABACEstimator->sao_offset_pars( testOffset[compIdx], compIdx, sliceEnabled[compIdx], bitDepths[CH_L] );

        double rate = FRAC_BITS_SCALE * m_CABACEstimator->getEstFracBits();

        cost = (double)dist[compIdx] + m_lambda[compIdx]*rate;

        if(cost < minCost)

        {

          minCost = cost;

          modeDist[compIdx] = dist[compIdx];

          modeParam[compIdx]= testOffset[compIdx];

          ctxBestLuma = SAOCtx( m_CABACEstimator->getCtx() );

        }

      }

    }

    m_CABACEstimator->getCtx() = SAOCtx( ctxBestLuma );

  }

  //------ chroma --------//

//"off" case as initial cost

  cost = 0;

  previousFracBits = 0;

  m_CABACEstimator->resetBits();

  for(uint32_t componentIndex = COMP_Cb; componentIndex < numberOfComponents; componentIndex++)

  {

    const ComponentID component = ComponentID(componentIndex);

    modeParam[component].modeIdc = SAO_MODE_OFF;

    modeDist [component]         = 0;

    m_CABACEstimator->sao_offset_pars( modeParam[component], component, sliceEnabled[component], bitDepths[CH_C] );

    const uint64_t currentFracBits = m_CABACEstimator->getEstFracBits();

    cost += m_lambda[component] * FRAC_BITS_SCALE * (currentFracBits - previousFracBits);

    previousFracBits = currentFracBits;

  }

  minCost = cost;

  //doesn't need to store cabac status here since the whole CTU parameters will be re-encoded at the end of this function

  for(int typeIdc=0; typeIdc< NUM_SAO_NEW_TYPES; typeIdc++)

  {

    m_CABACEstimator->getCtx() = SAOCtx( ctxBestLuma );

    m_CABACEstimator->resetBits();

    previousFracBits = 0;

    cost = 0;

    for(uint32_t componentIndex = COMP_Cb; componentIndex < numberOfComponents; componentIndex++)

    {

      const ComponentID component = ComponentID(componentIndex);

      if(!sliceEnabled[component])

      {

        testOffset[component].modeIdc = SAO_MODE_OFF;

        dist[component]= 0;

        continue;

      }

      testOffset[component].modeIdc = SAO_MODE_NEW;

      testOffset[component].typeIdc = typeIdc;

      //derive offset & get distortion

      deriveOffsets(component, bitDepths[CH_C], typeIdc, blkStats[ctuRsAddr][component][typeIdc], testOffset[component].offset, testOffset[component].typeAuxInfo);

      invertQuantOffsets(component, typeIdc, testOffset[component].typeAuxInfo, invQuantOffset, testOffset[component].offset);

      dist[component] = getDistortion(bitDepths[CH_C], typeIdc, testOffset[component].typeAuxInfo, invQuantOffset, blkStats[ctuRsAddr][component][typeIdc]);

      m_CABACEstimator->sao_offset_pars( testOffset[component], component, sliceEnabled[component], bitDepths[CH_C] );

      const uint64_t currentFracBits = m_CABACEstimator->getEstFracBits();

      cost += dist[component] + (m_lambda[component] * FRAC_BITS_SCALE * (currentFracBits - previousFracBits));

      previousFracBits = currentFracBits;

    }

    if(cost < minCost)

    {

      minCost = cost;

      for(uint32_t componentIndex = COMP_Cb; componentIndex < numberOfComponents; componentIndex++)

      {

        modeDist[componentIndex]  = dist[componentIndex];

        modeParam[componentIndex] = testOffset[componentIndex];

      }

    }

  } // SAO_TYPE loop

  //----- re-gen rate & normalized cost----//

  modeNormCost = 0;

  for(uint32_t componentIndex = COMP_Y; componentIndex < numberOfComponents; componentIndex++)

  {

    modeNormCost += (double)modeDist[componentIndex] / m_lambda[componentIndex];

  }

  m_CABACEstimator->getCtx() = SAOCtx( ctxStartBlk );

  m_CABACEstimator->resetBits();

  m_CABACEstimator->sao_block_pars( modeParam, bitDepths, sliceEnabled, (mergeList[SAO_MERGE_LEFT]!= NULL), (mergeList[SAO_MERGE_ABOVE]!= NULL), false );

  modeNormCost += FRAC_BITS_SCALE * m_CABACEstimator->getEstFracBits();

}

void EncSampleAdaptiveOffset::deriveModeMergeRDO(const BitDepths &bitDepths, int ctuRsAddr, SAOBlkParam* mergeList[NUM_SAO_MERGE_TYPES], const bool* sliceEnabled, const std::vector<SAOStatData**>& blkStats, SAOBlkParam& modeParam, double& modeNormCost )

{

  modeNormCost = MAX_DOUBLE;

  double cost;

  SAOBlkParam testBlkParam;

  const int numberOfComponents = m_numberOfComponents;

  const TempCtx ctxStart  ( m_CtxCache, SAOCtx( m_CABACEstimator->getCtx() ) );

  TempCtx       ctxBest   ( m_CtxCache );

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

  {

    if(mergeList[mergeType] == NULL)

    {

      continue;

    }

    testBlkParam = *(mergeList[mergeType]);

    //normalized distortion

    double normDist=0;

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

    {

      testBlkParam[compIdx].modeIdc = SAO_MODE_MERGE;

      testBlkParam[compIdx].typeIdc = mergeType;

      SAOOffset& mergedOffsetParam = (*(mergeList[mergeType]))[compIdx];

      if( mergedOffsetParam.modeIdc != SAO_MODE_OFF)

      {

        //offsets have been reconstructed. Don't call inversed quantization function.

        normDist += (((double)getDistortion(bitDepths[toChannelType(ComponentID(compIdx))], mergedOffsetParam.typeIdc, mergedOffsetParam.typeAuxInfo, mergedOffsetParam.offset, blkStats[ctuRsAddr][compIdx][mergedOffsetParam.typeIdc]))

                       /m_lambda[compIdx] );

      }

    }

    //rate

    m_CABACEstimator->getCtx() = SAOCtx( ctxStart );

    m_CABACEstimator->resetBits();

    m_CABACEstimator->sao_block_pars( testBlkParam, bitDepths, sliceEnabled, (mergeList[SAO_MERGE_LEFT]!= NULL), (mergeList[SAO_MERGE_ABOVE]!= NULL), false );

    double rate = FRAC_BITS_SCALE * m_CABACEstimator->getEstFracBits();

    cost = normDist+rate;

    if(cost < modeNormCost)

    {

      modeNormCost = cost;

      modeParam    = testBlkParam;

      ctxBest      = SAOCtx( m_CABACEstimator->getCtx() );

    }

  }

  if( modeNormCost < MAX_DOUBLE )

  {

    m_CABACEstimator->getCtx() = SAOCtx( ctxBest );

  }

}

void EncSampleAdaptiveOffset::getBlkStats(const ComponentID compIdx, const int channelBitDepth, SAOStatData* statsDataTypes

                        , Pel* srcBlk, Pel* orgBlk, int srcStride, int orgStride, int width, int height

                        , bool isLeftAvail,  bool isRightAvail, bool isAboveAvail, bool isBelowAvail, bool isAboveLeftAvail, bool isAboveRightAvail )

{

  int x, startX, startY, endX, endY, edgeType, firstLineStartX, firstLineEndX;

  int64_t *diff, *count;

  Pel* srcLine, *orgLine;

  const int skipLinesR = compIdx == COMP_Y ? 5 : 3;

  const int skipLinesB = compIdx == COMP_Y ? 4 : 2;

  for(int typeIdx=0; typeIdx< NUM_SAO_NEW_TYPES; typeIdx++)

  {

    SAOStatData& statsData= statsDataTypes[typeIdx];

    statsData.reset();

    srcLine = srcBlk;

    orgLine = orgBlk;

    diff    = statsData.diff;

    count   = statsData.count;

    switch(typeIdx)

    {

    case SAO_TYPE_EO_0:

      {

        endY   =  isBelowAvail ? (height - skipLinesB) : height;

        startX = (isLeftAvail  ? 0 : 1);

        endX   = (isRightAvail ? (width - skipLinesR) : (width - 1));

        calcSaoStatisticsEo0(width,startX,endX,endY,srcLine,orgLine,srcStride,orgStride,count,diff);

      }

      break;

    case SAO_TYPE_EO_90:

      {

        int8_t *signUpLine = &m_signLineBuf1[0];

        startX = 0;

        startY = isAboveAvail ? 0 : 1;

        endX   = (isRightAvail ? (width - skipLinesR) : width);

        endY   = isBelowAvail ? (height - skipLinesB) : (height - 1);

        if (!isAboveAvail)

        {

          srcLine += srcStride;

          orgLine += orgStride;

        }

        calcSaoStatisticsEo90(width,endX,startY,endY,srcLine,orgLine,srcStride,orgStride,count,diff,signUpLine);

      }

      break;

    case SAO_TYPE_EO_135:

      {

        diff +=2;

        count+=2;

        int8_t *signUpLine, *signDownLine;

        signUpLine  = &m_signLineBuf1[0];

        signDownLine= &m_signLineBuf2[0];

        startX = isLeftAvail  ? 0 : 1;

        endX   = isRightAvail ? (width - skipLinesR): (width - 1);

        endY   = isBelowAvail ? (height - skipLinesB) : (height - 1);

        //prepare 2nd line's upper sign

        Pel* srcLineBelow = srcLine + srcStride;

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

        {

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

        }

        //1st line

        Pel* srcLineAbove = srcLine - srcStride;

        firstLineStartX = isAboveLeftAvail ? 0    : 1;

        firstLineEndX   = isAboveAvail     ? endX : 1;

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

        {

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

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

          count[edgeType] ++;

        }

        srcLine  += srcStride;

        orgLine  += orgStride;

        calcSaoStatisticsEo135(width,startX,endX,endY,srcLine,orgLine,srcStride,orgStride,count,diff,signUpLine,signDownLine);

      }

      break;

    case SAO_TYPE_EO_45:

      {

        diff +=2;

        count+=2;

        int8_t *signUpLine = &m_signLineBuf1[1];

        startX = isLeftAvail  ? 0 : 1;

        endX   = isRightAvail ? (width - skipLinesR) : (width - 1);

        endY   = isBelowAvail ? (height - skipLinesB) : (height - 1);

        //prepare 2nd line upper sign

        Pel* srcLineBelow = srcLine + srcStride;

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

        {

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

        }

        //first line

        Pel* srcLineAbove = srcLine - srcStride;

        firstLineStartX = isAboveAvail ? startX : endX;

        firstLineEndX   = (!isRightAvail && isAboveRightAvail) ? width : endX;

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

        {

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

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

          count[edgeType] ++;

        }

        srcLine += srcStride;

        orgLine += orgStride;

        calcSaoStatisticsEo45(width,startX,endX,endY,srcLine,orgLine,srcStride,orgStride,count,diff,signUpLine);

      }

      break;

    case SAO_TYPE_BO:

      {

        startX = 0;

        endX   = isRightAvail ? (width - skipLinesR) : width;

        endY   = isBelowAvail ? (height- skipLinesB) : height;

        calcSaoStatisticsBo(width,endX,endY,srcLine,orgLine,srcStride,orgStride,channelBitDepth,count,diff);

      }

      break;

    default:

      {

        THROW("Not a supported SAO type");

      }

    }

  }

}

void EncSampleAdaptiveOffset::deriveLoopFilterBoundaryAvailibility(CodingStructure& cs, const Position& pos, bool& isLeftAvail, bool& isAboveAvail, bool& isAboveLeftAvail) const

{

  const bool isLoopFiltAcrossSlicePPS = cs.pps->loopFilterAcrossSlicesEnabled;

  const bool isLoopFiltAcrossTilePPS = cs.pps->loopFilterAcrossTilesEnabled;

  const int width = cs.pcv->maxCUSize;

  const int height = cs.pcv->maxCUSize;

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

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

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

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

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

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

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

  if (!isLoopFiltAcrossSlicePPS)

  {

    isLeftAvail      = (cuLeft == NULL)      ? false : CU::isSameSlice(*cuCurr, *cuLeft);

    isAboveAvail     = (cuAbove == NULL)     ? false : CU::isSameSlice(*cuCurr, *cuAbove);

    isAboveLeftAvail = (cuAboveLeft == NULL) ? false : CU::isSameSlice(*cuCurr, *cuAboveLeft);

  }

  else

  {

    isLeftAvail      = (cuLeft != NULL);

    isAboveAvail     = (cuAbove != NULL);

    isAboveLeftAvail = (cuAboveLeft != NULL);

  }

  if (!isLoopFiltAcrossTilePPS)

  {

    isLeftAvail      = (!isLeftAvail)      ? false : CU::isSameTile(*cuCurr, *cuLeft);

    isAboveAvail     = (!isAboveAvail)     ? false : CU::isSameTile(*cuCurr, *cuAbove);

    isAboveLeftAvail = (!isAboveLeftAvail) ? false : CU::isSameTile(*cuCurr, *cuAboveLeft);

  }

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

  if (!curSubPic.loopFilterAcrossSubPicEnabled )

  {

    isLeftAvail      = (!isLeftAvail)      ? false : CU::isSameSubPic(*cuCurr, *cuLeft);

    isAboveAvail     = (!isAboveAvail)     ? false : CU::isSameSubPic(*cuCurr, *cuAbove);

    isAboveLeftAvail = (!isAboveLeftAvail) ? false : CU::isSameSubPic(*cuCurr, *cuAboveLeft);

  }

}

} // namespace vvenc

//! \}