InterPrediction.cpp

    }
    pcYUVTemp = pcYuvSrc1;
    pcPadTemp = pcPad1;
  }
}

uint64_t InterPrediction::xDMVRCost(int bitDepth, Pel* pOrg, uint32_t refStride, const Pel* pRef, uint32_t orgStride, int width, int height)
{
  DistParam cDistParam;
  cDistParam.applyWeight = false;
  cDistParam.useMR = false;
  m_pcRdCost->setDistParam(cDistParam, pOrg, pRef, orgStride, refStride, bitDepth, COMPONENT_Y, width, height, 1);
  uint64_t uiCost = cDistParam.distFunc(cDistParam);
  return uiCost>>1;
}

void xDMVRSubPixelErrorSurface(bool notZeroCost, int16_t *totalDeltaMV, int16_t *deltaMV, uint64_t *pSADsArray)
{

  int sadStride = (((2 * DMVR_NUM_ITERATION) + 1));
  uint64_t sadbuffer[5];
  if (notZeroCost && (abs(totalDeltaMV[0]) != (2 << MV_FRACTIONAL_BITS_INTERNAL))
    && (abs(totalDeltaMV[1]) != (2 << MV_FRACTIONAL_BITS_INTERNAL)))
  {
    int32_t tempDeltaMv[2] = { 0,0 };
    sadbuffer[0] = pSADsArray[0];
    sadbuffer[1] = pSADsArray[-1];
    sadbuffer[2] = pSADsArray[-sadStride];
    sadbuffer[3] = pSADsArray[1];
    sadbuffer[4] = pSADsArray[sadStride];
    xSubPelErrorSrfc(sadbuffer, tempDeltaMv);
    totalDeltaMV[0] += tempDeltaMv[0];
    totalDeltaMV[1] += tempDeltaMv[1];
  }
}

void InterPrediction::xinitMC(PredictionUnit& pu, const ClpRngs &clpRngs)
{
  const int refIdx0 = pu.refIdx[0];
  const int refIdx1 = pu.refIdx[1];
  /*use merge MV as starting MV*/
  Mv mergeMVL0(pu.mv[REF_PIC_LIST_0]);
  Mv mergeMVL1(pu.mv[REF_PIC_LIST_1]);

  /*Clip the starting MVs*/
  clipMv( mergeMVL0, pu.lumaPos(), pu.lumaSize(), *pu.cs->sps, *pu.cs->pps );
  clipMv( mergeMVL1, pu.lumaPos(), pu.lumaSize(), *pu.cs->sps, *pu.cs->pps );

  /*L0 MC for refinement*/
  {
    int offset;
    int leftPixelExtra = (NTAPS_LUMA >> 1) - 1;
    offset = (DMVR_NUM_ITERATION + leftPixelExtra) * (m_cYuvRefBuffDMVRL0.bufs[COMPONENT_Y].stride + 1);
    offset += (-(int)DMVR_NUM_ITERATION)* (int)m_cYuvRefBuffDMVRL0.bufs[COMPONENT_Y].stride;
    offset += (-(int)DMVR_NUM_ITERATION);
    PelBuf srcBuf = m_cYuvRefBuffDMVRL0.bufs[COMPONENT_Y];
    PelUnitBuf yuvPredTempL0 = PelUnitBuf(pu.chromaFormat, PelBuf(m_cYuvPredTempDMVRL0,
      m_biLinearBufStride
      , pu.lwidth() + (2 * DMVR_NUM_ITERATION), pu.lheight() + (2 * DMVR_NUM_ITERATION)));

    xPredInterBlk( COMPONENT_Y, pu, pu.cu->slice->getRefPic( REF_PIC_LIST_0, refIdx0 )->unscaledPic, mergeMVL0, yuvPredTempL0, true, clpRngs.comp[COMPONENT_Y],
      false, false, pu.cu->slice->getScalingRatio( REF_PIC_LIST_0, refIdx0 ), pu.lwidth() + ( 2 * DMVR_NUM_ITERATION ), pu.lheight() + ( 2 * DMVR_NUM_ITERATION ), true, ( (Pel *)srcBuf.buf ) + offset, srcBuf.stride );
  }

  /*L1 MC for refinement*/
  {
    int offset;
    int leftPixelExtra = (NTAPS_LUMA >> 1) - 1;
    offset = (DMVR_NUM_ITERATION + leftPixelExtra) * (m_cYuvRefBuffDMVRL1.bufs[COMPONENT_Y].stride + 1);
    offset += (-(int)DMVR_NUM_ITERATION)* (int)m_cYuvRefBuffDMVRL1.bufs[COMPONENT_Y].stride;
    offset += (-(int)DMVR_NUM_ITERATION);
    PelBuf srcBuf = m_cYuvRefBuffDMVRL1.bufs[COMPONENT_Y];
    PelUnitBuf yuvPredTempL1 = PelUnitBuf(pu.chromaFormat, PelBuf(m_cYuvPredTempDMVRL1,
      m_biLinearBufStride
      , pu.lwidth() + (2 * DMVR_NUM_ITERATION), pu.lheight() + (2 * DMVR_NUM_ITERATION)));

    xPredInterBlk( COMPONENT_Y, pu, pu.cu->slice->getRefPic( REF_PIC_LIST_1, refIdx1 )->unscaledPic, mergeMVL1, yuvPredTempL1, true, clpRngs.comp[COMPONENT_Y],
      false, false, pu.cu->slice->getScalingRatio( REF_PIC_LIST_1, refIdx1 ), pu.lwidth() + ( 2 * DMVR_NUM_ITERATION ), pu.lheight() + ( 2 * DMVR_NUM_ITERATION ), true, ( (Pel *)srcBuf.buf ) + offset, srcBuf.stride );
  }
}

void InterPrediction::xProcessDMVR(PredictionUnit& pu, PelUnitBuf &pcYuvDst, const ClpRngs &clpRngs, const bool bioApplied)
{
  int iterationCount = 1;
  /*Always High Precision*/
  int mvShift = MV_FRACTIONAL_BITS_INTERNAL;

  /*use merge MV as starting MV*/
  Mv mergeMv[] = { pu.mv[REF_PIC_LIST_0] , pu.mv[REF_PIC_LIST_1] };

  m_biLinearBufStride = (MAX_CU_SIZE + (2 * DMVR_NUM_ITERATION));

  int dy = std::min<int>(pu.lumaSize().height, DMVR_SUBCU_HEIGHT);
  int dx = std::min<int>(pu.lumaSize().width,  DMVR_SUBCU_WIDTH);
  Position puPos = pu.lumaPos();

  int bd = pu.cs->slice->getClpRngs().comp[COMPONENT_Y].bd;

  int            bioEnabledThres = 2 * dy * dx;
  bool           bioAppliedType[MAX_NUM_SUBCU_DMVR];
  {
    int num = 0;

    int scaleX = getComponentScaleX(COMPONENT_Cb, pu.chromaFormat);
    int scaleY = getComponentScaleY(COMPONENT_Cb, pu.chromaFormat);
    m_biLinearBufStride = (dx + (2 * DMVR_NUM_ITERATION));
    // point mc buffer to cetre point to avoid multiplication to reach each iteration to the begining
    Pel *biLinearPredL0 = m_cYuvPredTempDMVRL0 + (DMVR_NUM_ITERATION * m_biLinearBufStride) + DMVR_NUM_ITERATION;
    Pel *biLinearPredL1 = m_cYuvPredTempDMVRL1 + (DMVR_NUM_ITERATION * m_biLinearBufStride) + DMVR_NUM_ITERATION;

    PredictionUnit subPu = pu;
    subPu.UnitArea::operator=(UnitArea(pu.chromaFormat, Area(puPos.x, puPos.y, dx, dy)));
    m_cYuvRefBuffDMVRL0 = (pu.chromaFormat == CHROMA_400 ?
      PelUnitBuf(pu.chromaFormat, PelBuf(m_cRefSamplesDMVRL0[0], pcYuvDst.Y())) :
      PelUnitBuf(pu.chromaFormat, PelBuf(m_cRefSamplesDMVRL0[0], pcYuvDst.Y()),
        PelBuf(m_cRefSamplesDMVRL0[1], pcYuvDst.Cb()), PelBuf(m_cRefSamplesDMVRL0[2], pcYuvDst.Cr())));
    m_cYuvRefBuffDMVRL0 = m_cYuvRefBuffDMVRL0.subBuf(UnitAreaRelative(pu, subPu));

    m_cYuvRefBuffDMVRL1 = (pu.chromaFormat == CHROMA_400 ?
      PelUnitBuf(pu.chromaFormat, PelBuf(m_cRefSamplesDMVRL1[0], pcYuvDst.Y())) :
      PelUnitBuf(pu.chromaFormat, PelBuf(m_cRefSamplesDMVRL1[0], pcYuvDst.Y()), PelBuf(m_cRefSamplesDMVRL1[1], pcYuvDst.Cb()),
        PelBuf(m_cRefSamplesDMVRL1[2], pcYuvDst.Cr())));
    m_cYuvRefBuffDMVRL1 = m_cYuvRefBuffDMVRL1.subBuf(UnitAreaRelative(pu, subPu));

    PelUnitBuf srcPred0 = (pu.chromaFormat == CHROMA_400 ?
      PelUnitBuf(pu.chromaFormat, PelBuf(m_acYuvPred[0][0], pcYuvDst.Y())) :
      PelUnitBuf(pu.chromaFormat, PelBuf(m_acYuvPred[0][0], pcYuvDst.Y()), PelBuf(m_acYuvPred[0][1], pcYuvDst.Cb()), PelBuf(m_acYuvPred[0][2], pcYuvDst.Cr())));
    PelUnitBuf srcPred1 = (pu.chromaFormat == CHROMA_400 ?
      PelUnitBuf(pu.chromaFormat, PelBuf(m_acYuvPred[1][0], pcYuvDst.Y())) :
      PelUnitBuf(pu.chromaFormat, PelBuf(m_acYuvPred[1][0], pcYuvDst.Y()), PelBuf(m_acYuvPred[1][1], pcYuvDst.Cb()), PelBuf(m_acYuvPred[1][2], pcYuvDst.Cr())));

    srcPred0 = srcPred0.subBuf(UnitAreaRelative(pu, subPu));
    srcPred1 = srcPred1.subBuf(UnitAreaRelative(pu, subPu));

    int yStart = 0;
    for (int y = puPos.y; y < (puPos.y + pu.lumaSize().height); y = y + dy, yStart = yStart + dy)
    {
      for (int x = puPos.x, xStart = 0; x < (puPos.x + pu.lumaSize().width); x = x + dx, xStart = xStart + dx)
      {
        PredictionUnit subPu = pu;
        subPu.UnitArea::operator=(UnitArea(pu.chromaFormat, Area(x, y, dx, dy)));
        xPrefetch(subPu, m_cYuvRefBuffDMVRL0, REF_PIC_LIST_0, 1);
        xPrefetch(subPu, m_cYuvRefBuffDMVRL1, REF_PIC_LIST_1, 1);

        xinitMC(subPu, clpRngs);

        uint64_t minCost = MAX_UINT64;
        bool notZeroCost = true;
        int16_t totalDeltaMV[2] = { 0,0 };
        int16_t deltaMV[2] = { 0, 0 };
        uint64_t  *pSADsArray;
        for (int i = 0; i < (((2 * DMVR_NUM_ITERATION) + 1) * ((2 * DMVR_NUM_ITERATION) + 1)); i++)
        {
          m_SADsArray[i] = MAX_UINT64;
        }
        pSADsArray = &m_SADsArray[(((2 * DMVR_NUM_ITERATION) + 1) * ((2 * DMVR_NUM_ITERATION) + 1)) >> 1];
        for (int i = 0; i < iterationCount; i++)
        {
          deltaMV[0] = 0;
          deltaMV[1] = 0;
          Pel *addrL0 = biLinearPredL0 + totalDeltaMV[0] + (totalDeltaMV[1] * m_biLinearBufStride);
          Pel *addrL1 = biLinearPredL1 - totalDeltaMV[0] - (totalDeltaMV[1] * m_biLinearBufStride);
          if (i == 0)
          {
            minCost = xDMVRCost(clpRngs.comp[COMPONENT_Y].bd, addrL0, m_biLinearBufStride, addrL1, m_biLinearBufStride, dx, dy);
            minCost -= (minCost >>2);
            if (minCost < (dx * dy))
            {
              notZeroCost = false;
              break;
            }
            pSADsArray[0] = minCost;
          }
          if (!minCost)
          {
            notZeroCost = false;
            break;
          }

          xBIPMVRefine(bd, addrL0, addrL1, minCost, deltaMV, pSADsArray, dx, dy);

          if (deltaMV[0] == 0 && deltaMV[1] == 0)
          {
            break;
          }
          totalDeltaMV[0] += deltaMV[0];
          totalDeltaMV[1] += deltaMV[1];
          pSADsArray += ((deltaMV[1] * (((2 * DMVR_NUM_ITERATION) + 1))) + deltaMV[0]);
        }

        bioAppliedType[num] = (minCost < bioEnabledThres) ? false : bioApplied;
        totalDeltaMV[0] = (totalDeltaMV[0] << mvShift);
        totalDeltaMV[1] = (totalDeltaMV[1] << mvShift);
        xDMVRSubPixelErrorSurface(notZeroCost, totalDeltaMV, deltaMV, pSADsArray);

        pu.mvdL0SubPu[num] = Mv(totalDeltaMV[0], totalDeltaMV[1]);
        PelUnitBuf subPredBuf = pcYuvDst.subBuf(UnitAreaRelative(pu, subPu));

        bool blockMoved = false;
        if (pu.mvdL0SubPu[num] != Mv(0, 0))
        {
          blockMoved = true;
          xPrefetch(subPu, m_cYuvRefBuffDMVRL0, REF_PIC_LIST_0, 0);
          xPrefetch(subPu, m_cYuvRefBuffDMVRL1, REF_PIC_LIST_1, 0);
          xPad(subPu, m_cYuvRefBuffDMVRL0, REF_PIC_LIST_0);
          xPad(subPu, m_cYuvRefBuffDMVRL1, REF_PIC_LIST_1);
        }

        int dstStride[MAX_NUM_COMPONENT] = { pcYuvDst.bufs[COMPONENT_Y].stride, pcYuvDst.bufs[COMPONENT_Cb].stride, pcYuvDst.bufs[COMPONENT_Cr].stride };
        subPu.mv[0] = mergeMv[REF_PIC_LIST_0] + pu.mvdL0SubPu[num];
        subPu.mv[1] = mergeMv[REF_PIC_LIST_1] - pu.mvdL0SubPu[num];

        subPu.mv[0].clipToStorageBitDepth();
        subPu.mv[1].clipToStorageBitDepth();

        xFinalPaddedMCForDMVR(subPu, srcPred0, srcPred1, m_cYuvRefBuffDMVRL0, m_cYuvRefBuffDMVRL1, bioAppliedType[num], mergeMv
          , blockMoved
        );

        subPredBuf.bufs[COMPONENT_Y].buf = pcYuvDst.bufs[COMPONENT_Y].buf + xStart + yStart * dstStride[COMPONENT_Y];

        subPredBuf.bufs[COMPONENT_Cb].buf = pcYuvDst.bufs[COMPONENT_Cb].buf + (xStart >> scaleX) + ((yStart >> scaleY) * dstStride[COMPONENT_Cb]);

        subPredBuf.bufs[COMPONENT_Cr].buf = pcYuvDst.bufs[COMPONENT_Cr].buf + (xStart >> scaleX) + ((yStart >> scaleY) * dstStride[COMPONENT_Cr]);

        xWeightedAverage(subPu, srcPred0, srcPred1, subPredBuf, subPu.cu->slice->getSPS()->getBitDepths(), subPu.cu->slice->clpRngs(), bioAppliedType[num]);
        num++;
      }
    }
  }
  JVET_J0090_SET_CACHE_ENABLE(true);
}
#if JVET_J0090_MEMORY_BANDWITH_MEASURE
void InterPrediction::cacheAssign( CacheModel *cache )
{
  m_cacheModel = cache;
  m_if.cacheAssign( cache );
  m_if.initInterpolationFilter( !cache->isCacheEnable() );
}
#endif

void InterPrediction::xFillIBCBuffer(CodingUnit &cu)
{
  for (auto &currPU : CU::traverseTUs(cu))
  {
    for (const CompArea &area : currPU.blocks)
    {
      if (!area.valid())
        continue;

      const unsigned int lcuWidth = cu.cs->slice->getSPS()->getMaxCUWidth();
      const int shiftSampleHor = ::getComponentScaleX(area.compID, cu.chromaFormat);
      const int shiftSampleVer = ::getComponentScaleY(area.compID, cu.chromaFormat);
      const int ctuSizeLog2Ver = floorLog2(lcuWidth) - shiftSampleVer;
      const int pux = area.x & ((m_IBCBufferWidth >> shiftSampleHor) - 1);
      const int puy = area.y & (( 1 << ctuSizeLog2Ver ) - 1);
      const CompArea dstArea = CompArea(area.compID, cu.chromaFormat, Position(pux, puy), Size(area.width, area.height));
      CPelBuf srcBuf = cu.cs->getRecoBuf(area);
      PelBuf dstBuf = m_IBCBuffer.getBuf(dstArea);

      dstBuf.copyFrom(srcBuf);
    }
  }
}

void InterPrediction::xIntraBlockCopy(PredictionUnit &pu, PelUnitBuf &predBuf, const ComponentID compID)
{
  const unsigned int lcuWidth = pu.cs->slice->getSPS()->getMaxCUWidth();
  const int shiftSampleHor = ::getComponentScaleX(compID, pu.chromaFormat);
  const int shiftSampleVer = ::getComponentScaleY(compID, pu.chromaFormat);
  const int ctuSizeLog2Ver = floorLog2(lcuWidth) - shiftSampleVer;
  pu.bv = pu.mv[REF_PIC_LIST_0];
  pu.bv.changePrecision(MV_PRECISION_INTERNAL, MV_PRECISION_INT);
  int refx, refy;
  if (compID == COMPONENT_Y)
  {
    refx = pu.Y().x + pu.bv.hor;
    refy = pu.Y().y + pu.bv.ver;
  }
  else
  {//Cb or Cr
    refx = pu.Cb().x + (pu.bv.hor >> shiftSampleHor);
    refy = pu.Cb().y + (pu.bv.ver >> shiftSampleVer);
  }
  refx &= ((m_IBCBufferWidth >> shiftSampleHor) - 1);
  refy &= ((1 << ctuSizeLog2Ver) - 1);

  if (refx + predBuf.bufs[compID].width <= (m_IBCBufferWidth >> shiftSampleHor))
  {
    const CompArea srcArea = CompArea(compID, pu.chromaFormat, Position(refx, refy), Size(predBuf.bufs[compID].width, predBuf.bufs[compID].height));
    const CPelBuf refBuf = m_IBCBuffer.getBuf(srcArea);
    predBuf.bufs[compID].copyFrom(refBuf);
  }
  else
  {//wrap around
    int width = (m_IBCBufferWidth >> shiftSampleHor) - refx;
    CompArea srcArea = CompArea(compID, pu.chromaFormat, Position(refx, refy), Size(width, predBuf.bufs[compID].height));
    CPelBuf srcBuf = m_IBCBuffer.getBuf(srcArea);
    PelBuf dstBuf = PelBuf(predBuf.bufs[compID].bufAt(Position(0, 0)), predBuf.bufs[compID].stride, Size(width, predBuf.bufs[compID].height));
    dstBuf.copyFrom(srcBuf);

    width = refx + predBuf.bufs[compID].width - (m_IBCBufferWidth >> shiftSampleHor);
    srcArea = CompArea(compID, pu.chromaFormat, Position(0, refy), Size(width, predBuf.bufs[compID].height));
    srcBuf = m_IBCBuffer.getBuf(srcArea);
    dstBuf = PelBuf(predBuf.bufs[compID].bufAt(Position((m_IBCBufferWidth >> shiftSampleHor) - refx, 0)), predBuf.bufs[compID].stride, Size(width, predBuf.bufs[compID].height));
    dstBuf.copyFrom(srcBuf);
  }
}

void InterPrediction::resetIBCBuffer(const ChromaFormat chromaFormatIDC, const int ctuSize)
{
  const UnitArea area = UnitArea(chromaFormatIDC, Area(0, 0, m_IBCBufferWidth, ctuSize));
  m_IBCBuffer.getBuf(area).fill(-1);
}

void InterPrediction::resetVPDUforIBC(const ChromaFormat chromaFormatIDC, const int ctuSize, const int vSize, const int xPos, const int yPos)
{
  const UnitArea area = UnitArea(chromaFormatIDC, Area(xPos & (m_IBCBufferWidth - 1), yPos & (ctuSize - 1), vSize, vSize));
  m_IBCBuffer.getBuf(area).fill(-1);
}

bool InterPrediction::isLumaBvValid(const int ctuSize, const int xCb, const int yCb, const int width, const int height, const int xBv, const int yBv)
{
  if(((yCb + yBv) & (ctuSize - 1)) + height > ctuSize)
  {
    return false;
  }
  int refTLx = xCb + xBv;
  int refTLy = (yCb + yBv) & (ctuSize - 1);
  PelBuf buf = m_IBCBuffer.Y();
  for(int x = 0; x < width; x += 4)
  {
    for(int y = 0; y < height; y += 4)
    {
      if(buf.at((x + refTLx) & (m_IBCBufferWidth - 1), y + refTLy) == -1) return false;
      if(buf.at((x + 3 + refTLx) & (m_IBCBufferWidth - 1), y + refTLy) == -1) return false;
      if(buf.at((x + refTLx) & (m_IBCBufferWidth - 1), y + 3 + refTLy) == -1) return false;
      if(buf.at((x + 3 + refTLx) & (m_IBCBufferWidth - 1), y + 3 + refTLy) == -1) return false;
    }
  }
  return true;
}

bool InterPrediction::xPredInterBlkRPR( const std::pair<int, int>& scalingRatio, const PPS& pps, const CompArea &blk, const Picture* refPic, const Mv& mv, Pel* dst, const int dstStride, const bool bi, const bool wrapRef, const ClpRng& clpRng, const int filterIndex, const bool useAltHpelIf )
{
  const ChromaFormat  chFmt = blk.chromaFormat;
  const ComponentID compID = blk.compID;
  const bool          rndRes = !bi;

  int shiftHor = MV_FRACTIONAL_BITS_INTERNAL + ::getComponentScaleX( compID, chFmt );
  int shiftVer = MV_FRACTIONAL_BITS_INTERNAL + ::getComponentScaleY( compID, chFmt );

  int width = blk.width;
  int height = blk.height;
  CPelBuf refBuf;

  const bool scaled = scalingRatio != SCALE_1X;

  if( scaled )
  {
    int row, col;
    int refPicWidth = refPic->getPicWidthInLumaSamples();
    int refPicHeight = refPic->getPicHeightInLumaSamples();

#if JVET_P0088_P0353_RPR_FILTERS
    int xFilter = filterIndex;
    int yFilter = filterIndex;
    const int rprThreshold1 = ( 1 << SCALE_RATIO_BITS ) * 5 / 4; 
    const int rprThreshold2 = ( 1 << SCALE_RATIO_BITS ) * 7 / 4;
    if( filterIndex == 0 )
    {
      if( scalingRatio.first > rprThreshold2 )
      {
        xFilter = 4;
      }
      else if( scalingRatio.first > rprThreshold1 )
      {
        xFilter = 3;
      }

      if( scalingRatio.second > rprThreshold2 )
      {
        yFilter = 4;
      }
      else if( scalingRatio.second > rprThreshold1 )
      {
        yFilter = 3;
      }
    }
#endif

    const int posShift = SCALE_RATIO_BITS - 4;
    int stepX = ( scalingRatio.first + 8 ) >> 4;
    int stepY = ( scalingRatio.second + 8 ) >> 4;
    int64_t x0Int;
    int64_t y0Int;
    int offX = 1 << ( posShift - shiftHor - 1 );
    int offY = 1 << ( posShift - shiftVer - 1 );

    x0Int = ( ( blk.pos().x << ( 4 + ::getComponentScaleX( compID, chFmt ) ) ) + mv.getHor() )* (int64_t)scalingRatio.first;
    x0Int = SIGN( x0Int ) * ( ( llabs( x0Int ) + ( (long long)1 << ( 7 + ::getComponentScaleX( compID, chFmt ) ) ) ) >> ( 8 + ::getComponentScaleX( compID, chFmt ) ) );

    y0Int = ( ( blk.pos().y << ( 4 + ::getComponentScaleY( compID, chFmt ) ) ) + mv.getVer() )* (int64_t)scalingRatio.second;
    y0Int = SIGN( y0Int ) * ( ( llabs( y0Int ) + ( (long long)1 << ( 7 + ::getComponentScaleY( compID, chFmt ) ) ) ) >> ( 8 + ::getComponentScaleY( compID, chFmt ) ) );

    const int extSize = isLuma( compID ) ? 1 : 2;

    int vFilterSize = isLuma( compID ) ? NTAPS_LUMA : NTAPS_CHROMA;

    int yInt0 = ( (int32_t)y0Int + offY ) >> posShift;
    yInt0 = std::min( std::max( -4, yInt0 ), ( refPicHeight >> ::getComponentScaleY( compID, chFmt ) ) + 4 );

    int xInt0 = ( (int32_t)x0Int + offX ) >> posShift;
    xInt0 = std::min( std::max( -4, xInt0 ), ( refPicWidth >> ::getComponentScaleX( compID, chFmt ) ) + 4 );
        
    int refHeight = ((((int32_t)y0Int + (height-1) * stepY) + offY ) >> posShift) - ((((int32_t)y0Int + 0 * stepY) + offY ) >> posShift) + 1;

    refHeight = std::max<int>( 1, refHeight );

    CHECK( MAX_CU_SIZE * MAX_SCALING_RATIO < refHeight + vFilterSize - 1 + extSize, "Buffer size is not enough, increase MAX_SCALING_RATIO" );

    Pel buffer[( MAX_CU_SIZE + 16 ) * ( MAX_CU_SIZE * MAX_SCALING_RATIO + 16 )];

    int tmpStride = width;

    int xInt = 0, yInt = 0;

    for( col = 0; col < width; col++ )
    {
      int posX = (int32_t)x0Int + col * stepX;
      xInt = ( posX + offX ) >> posShift;
      xInt = std::min( std::max( -4, xInt ), ( refPicWidth >> ::getComponentScaleX( compID, chFmt ) ) + 4 );
      int xFrac = ( ( posX + offX ) >> ( posShift - shiftHor ) ) & ( ( 1 << shiftHor ) - 1 );

      CHECK( xInt0 > xInt, "Wrong horizontal starting point" );

      Position offset = Position( xInt, yInt0 );
      refBuf = refPic->getRecoBuf( CompArea( compID, chFmt, offset, Size( 1, refHeight ) ), wrapRef );
      Pel* tempBuf = buffer + col;

#if JVET_P0088_P0353_RPR_FILTERS
      m_if.filterHor( compID, (Pel*)refBuf.buf - ( ( vFilterSize >> 1 ) - 1 ) * refBuf.stride, refBuf.stride, tempBuf, tmpStride, 1, refHeight + vFilterSize - 1 + extSize, xFrac, false, chFmt, clpRng, xFilter, false, useAltHpelIf );
#else
      m_if.filterHor( compID, (Pel*)refBuf.buf - ( ( vFilterSize >> 1 ) - 1 ) * refBuf.stride, refBuf.stride, tempBuf, tmpStride, 1, refHeight + vFilterSize - 1 + extSize, xFrac, false, chFmt, clpRng, filterIndex, false, useAltHpelIf );
#endif
    }

    for( row = 0; row < height; row++ )
    {
      int posY = (int32_t)y0Int + row * stepY;
      yInt = ( posY + offY ) >> posShift;
      yInt = std::min( std::max( -4, yInt ), ( refPicHeight >> ::getComponentScaleY( compID, chFmt ) ) + 4 );
      int yFrac = ( ( posY + offY ) >> ( posShift - shiftVer ) ) & ( ( 1 << shiftVer ) - 1 );

      CHECK( yInt0 > yInt, "Wrong vertical starting point" );

      Pel* tempBuf = buffer + ( yInt - yInt0 ) * tmpStride;

      JVET_J0090_SET_CACHE_ENABLE( false );
#if JVET_P0088_P0353_RPR_FILTERS
      m_if.filterVer( compID, tempBuf + ( ( vFilterSize >> 1 ) - 1 ) * tmpStride, tmpStride, dst + row * dstStride, dstStride, width, 1, yFrac, false, rndRes, chFmt, clpRng, yFilter, false, useAltHpelIf );
#else
      m_if.filterVer( compID, tempBuf + ( ( vFilterSize >> 1 ) - 1 ) * tmpStride, tmpStride, dst + row * dstStride, dstStride, width, 1, yFrac, false, rndRes, chFmt, clpRng, filterIndex, false, useAltHpelIf );
#endif
      JVET_J0090_SET_CACHE_ENABLE( true );
    }

    Position offset = Position( xInt, yInt );
    refBuf = refPic->getRecoBuf( CompArea( compID, chFmt, offset, Size( 1, 1 ) ), wrapRef );
  }

  return scaled;
}