UnitTools.cpp

    break;
  case MD_ABOVE:
    neibPos = pos.offset(  0, -1 );
    break;
  case MD_ABOVE_RIGHT:
    neibPos = pos.offset(  1, -1 );
    break;
  case MD_BELOW_LEFT:
    neibPos = pos.offset( -1,  1 );
    break;
  case MD_ABOVE_LEFT:
    neibPos = pos.offset( -1, -1 );
    break;
  default:
    break;
  }

  neibPU = cs.getPURestricted( neibPos, pu, pu.chType );

  if( neibPU == NULL || !CU::isInter( *neibPU->cu ) )
  {
    return false;
  }

  const MotionInfo& neibMi        = neibPU->getMotionInfo( neibPos );

  const int        currRefPOC     = cs.slice->getRefPic( eRefPicList, iRefIdx )->getPOC();
  const RefPicList eRefPicList2nd = ( eRefPicList == REF_PIC_LIST_0 ) ? REF_PIC_LIST_1 : REF_PIC_LIST_0;

  for( int predictorSource = 0; predictorSource < 2; predictorSource++ ) // examine the indicated reference picture list, then if not available, examine the other list.
  {
    const RefPicList eRefPicListIndex = ( predictorSource == 0 ) ? eRefPicList : eRefPicList2nd;
    const int        neibRefIdx       = neibMi.refIdx[eRefPicListIndex];

    if( neibRefIdx >= 0 && currRefPOC == cs.slice->getRefPOC( eRefPicListIndex, neibRefIdx ) )
    {
      if( affine )
      {
        int i = 0;
        for( i = 0; i < info.numCand; i++ )
        {
          if( info.mvCand[i] == neibMi.mv[eRefPicListIndex] )
          {
            break;
          }
        }
        if( i == info.numCand )
        {
          info.mvCand[info.numCand++] = neibMi.mv[eRefPicListIndex];
#if !REMOVE_MV_ADAPT_PREC
          Mv cMvHigh = neibMi.mv[eRefPicListIndex];
          cMvHigh.setHighPrec();
#endif
//          CHECK( !neibMi.mv[eRefPicListIndex].highPrec, "Unexpected low precision mv.");
          return true;
        }
      }
      else
      {
        info.mvCand[info.numCand++] = neibMi.mv[eRefPicListIndex];
        return true;
      }
    }
  }


  return false;
}

/**
* \param pInfo
* \param eRefPicList
* \param iRefIdx
* \param uiPartUnitIdx
* \param eDir
* \returns bool
*/
bool PU::addMVPCandWithScaling( const PredictionUnit &pu, const RefPicList &eRefPicList, const int &iRefIdx, const Position &pos, const MvpDir &eDir, AMVPInfo &info, bool affine )
{
        CodingStructure &cs    = *pu.cs;
  const Slice &slice           = *cs.slice;
  const PredictionUnit *neibPU = NULL;
        Position neibPos;

  switch( eDir )
  {
  case MD_LEFT:
    neibPos = pos.offset( -1,  0 );
    break;
  case MD_ABOVE:
    neibPos = pos.offset(  0, -1 );
    break;
  case MD_ABOVE_RIGHT:
    neibPos = pos.offset(  1, -1 );
    break;
  case MD_BELOW_LEFT:
    neibPos = pos.offset( -1,  1 );
    break;
  case MD_ABOVE_LEFT:
    neibPos = pos.offset( -1, -1 );
    break;
  default:
    break;
  }

  neibPU = cs.getPURestricted( neibPos, pu, pu.chType );

  if( neibPU == NULL || !CU::isInter( *neibPU->cu ) )
  {
    return false;
  }

  const MotionInfo& neibMi        = neibPU->getMotionInfo( neibPos );

  const RefPicList eRefPicList2nd = ( eRefPicList == REF_PIC_LIST_0 ) ? REF_PIC_LIST_1 : REF_PIC_LIST_0;

  const int  currPOC            = slice.getPOC();
  const int  currRefPOC         = slice.getRefPic( eRefPicList, iRefIdx )->poc;
  const bool bIsCurrRefLongTerm = slice.getRefPic( eRefPicList, iRefIdx )->longTerm;
  const int  neibPOC            = currPOC;

  for( int predictorSource = 0; predictorSource < 2; predictorSource++ ) // examine the indicated reference picture list, then if not available, examine the other list.
  {
    const RefPicList eRefPicListIndex = (predictorSource == 0) ? eRefPicList : eRefPicList2nd;
    const int        neibRefIdx       = neibMi.refIdx[eRefPicListIndex];
    if( neibRefIdx >= 0 )
    {
      const bool bIsNeibRefLongTerm = slice.getRefPic(eRefPicListIndex, neibRefIdx)->longTerm;

      if (bIsCurrRefLongTerm == bIsNeibRefLongTerm)
      {
        Mv cMv = neibMi.mv[eRefPicListIndex];

        if( !( bIsCurrRefLongTerm /* || bIsNeibRefLongTerm*/) )
        {
          const int neibRefPOC = slice.getRefPOC( eRefPicListIndex, neibRefIdx );
          const int scale      = xGetDistScaleFactor( currPOC, currRefPOC, neibPOC, neibRefPOC );

          if( scale != 4096 )
          {
#if !REMOVE_MV_ADAPT_PREC
            if( slice.getSPS()->getSpsNext().getUseHighPrecMv() )
            {
              cMv.setHighPrec();
            }
#endif
            cMv = cMv.scaleMv( scale );
          }
        }

        if( affine )
        {
          int i;
          for( i = 0; i < info.numCand; i++ )
          {
            if( info.mvCand[i] == cMv )
            {
              break;
            }
          }
          if( i == info.numCand )
          {
            info.mvCand[info.numCand++] = cMv;
//            CHECK( !cMv.highPrec, "Unexpected low precision mv.");
            return true;
          }
        }
        else
        {
          info.mvCand[info.numCand++] = cMv;
          return true;
        }
      }
    }
  }


  return false;
}

#if JVET_L0266_HMVP
void PU::addAMVPHMVPCand(const PredictionUnit &pu, const RefPicList eRefPicList, const RefPicList eRefPicList2nd, const int currRefPOC, AMVPInfo &info, uint8_t imv)
{
  const Slice &slice = *(*pu.cs).slice;

  MotionInfo neibMi;
  int i = 0;
  unsigned imvShift = imv << 1;

  int num_avai_candInLUT = slice.getAvailableLUTMrgNum();
  int num_allowedCand = std::min(MAX_NUM_HMVP_AVMPCANDS, num_avai_candInLUT);

  for (int mrgIdx = 1; mrgIdx <= num_allowedCand; mrgIdx++)
  {
    if (info.numCand >= AMVP_MAX_NUM_CANDS)
    {
      return;
    }
    neibMi = slice.getMotionInfoFromLUTs(num_avai_candInLUT - mrgIdx);

    for (int predictorSource = 0; predictorSource < 2; predictorSource++) 
    {
      const RefPicList eRefPicListIndex = (predictorSource == 0) ? eRefPicList : eRefPicList2nd;
      const int        neibRefIdx = neibMi.refIdx[eRefPicListIndex];

      if (neibRefIdx >= 0 && currRefPOC == slice.getRefPOC(eRefPicListIndex, neibRefIdx))
      {
        Mv pmv = neibMi.mv[eRefPicListIndex];
        if (imv != 0)
        {
          roundMV(pmv, imvShift);
        }
        for (i = 0; i < info.numCand; i++)
        {
          if (pmv == info.mvCand[i])
          {
            break;
          }
        }
        if (i == info.numCand)
        {
          info.mvCand[info.numCand++] = pmv;
          if (info.numCand >= AMVP_MAX_NUM_CANDS)
          {
            return;
          }
        }
      }
    }
  }
}
#endif
bool PU::isBipredRestriction(const PredictionUnit &pu)
{
  const SPSNext &spsNext = pu.cs->sps->getSpsNext();
#if JVET_L0104_NO_4x4BI_INTER_CU
  if(pu.cu->lumaSize().width == 4 && pu.cu->lumaSize().height ==4 )
  {
    return true;
  }
#endif
  if( !pu.cs->pcv->only2Nx2N && !spsNext.getUseSubPuMvp() && pu.cu->lumaSize().width == 8 && ( pu.lumaSize().width < 8 || pu.lumaSize().height < 8 ) )
  {
    return true;
  }
  return false;
}


const PredictionUnit* getFirstAvailableAffineNeighbour( const PredictionUnit &pu )
{
  const Position posLT = pu.Y().topLeft();
  const Position posRT = pu.Y().topRight();
  const Position posLB = pu.Y().bottomLeft();

  const PredictionUnit* puLeft = pu.cs->getPURestricted( posLB.offset( -1, 0 ), pu, pu.chType );
  if( puLeft && puLeft->cu->affine )
  {
    return puLeft;
  }
  const PredictionUnit* puAbove = pu.cs->getPURestricted( posRT.offset( 0, -1 ), pu, pu.chType );
  if( puAbove && puAbove->cu->affine )
  {
    return puAbove;
  }
  const PredictionUnit* puAboveRight = pu.cs->getPURestricted( posRT.offset( 1, -1 ), pu, pu.chType );
  if( puAboveRight && puAboveRight->cu->affine )
  {
    return puAboveRight;
  }
  const PredictionUnit *puLeftBottom = pu.cs->getPURestricted( posLB.offset( -1, 1 ), pu, pu.chType );
  if( puLeftBottom && puLeftBottom->cu->affine )
  {
    return puLeftBottom;
  }
  const PredictionUnit *puAboveLeft = pu.cs->getPURestricted( posLT.offset( -1, -1 ), pu, pu.chType );
  if( puAboveLeft && puAboveLeft->cu->affine )
  {
    return puAboveLeft;
  }
  return nullptr;
}

bool PU::isAffineMrgFlagCoded( const PredictionUnit &pu )
{
  if ( pu.cu->lumaSize().width < 8 || pu.cu->lumaSize().height < 8 )
  {
    return false;
  }
  return getFirstAvailableAffineNeighbour( pu ) != nullptr;
}
#if JVET_L0646_GBI
void PU::getAffineMergeCand( const PredictionUnit &pu, MvField(*mvFieldNeighbours)[3], unsigned char &interDirNeighbours, unsigned char &gbiIdx, int &numValidMergeCand )
#else
void PU::getAffineMergeCand( const PredictionUnit &pu, MvField (*mvFieldNeighbours)[3], unsigned char &interDirNeighbours, int &numValidMergeCand )
#endif
{
  for ( int mvNum = 0; mvNum < 3; mvNum++ )
  {
    mvFieldNeighbours[0][mvNum].setMvField( Mv(), -1 );
    mvFieldNeighbours[1][mvNum].setMvField( Mv(), -1 );
  }

  const PredictionUnit* puFirstNeighbour = getFirstAvailableAffineNeighbour( pu );
  if( puFirstNeighbour == nullptr )
  {
    numValidMergeCand = -1;
#if JVET_L0646_GBI
    gbiIdx = GBI_DEFAULT;
#endif
    return;
  }
  else
  {
    numValidMergeCand = 1;
  }

  // get Inter Dir
  interDirNeighbours = puFirstNeighbour->getMotionInfo().interDir;

  pu.cu->affineType = puFirstNeighbour->cu->affineType;

  // derive Mv from neighbor affine block
  Mv cMv[3];
  if ( interDirNeighbours != 2 )
  {
    xInheritedAffineMv( pu, puFirstNeighbour, REF_PIC_LIST_0, cMv );
    for ( int mvNum = 0; mvNum < 3; mvNum++ )
    {
      mvFieldNeighbours[0][mvNum].setMvField( cMv[mvNum], puFirstNeighbour->refIdx[0] );
    }
  }

  if ( pu.cs->slice->isInterB() )
  {
    if ( interDirNeighbours != 1 )
    {
      xInheritedAffineMv( pu, puFirstNeighbour, REF_PIC_LIST_1, cMv );
      for ( int mvNum = 0; mvNum < 3; mvNum++ )
      {
        mvFieldNeighbours[1][mvNum].setMvField( cMv[mvNum], puFirstNeighbour->refIdx[1] );
      }
    }
  }
#if JVET_L0646_GBI
  gbiIdx = puFirstNeighbour->cu->GBiIdx;
#endif
}

void PU::setAllAffineMvField( PredictionUnit &pu, MvField *mvField, RefPicList eRefList )
{
  // Set Mv
  Mv mv[3];
  for ( int i = 0; i < 3; i++ )
  {
    mv[i] = mvField[i].mv;
  }
  setAllAffineMv( pu, mv[0], mv[1], mv[2], eRefList );

  // Set RefIdx
  CHECK( mvField[0].refIdx != mvField[1].refIdx || mvField[0].refIdx != mvField[2].refIdx, "Affine mv corners don't have the same refIdx." );
  pu.refIdx[eRefList] = mvField[0].refIdx;
}

void PU::setAllAffineMv( PredictionUnit& pu, Mv affLT, Mv affRT, Mv affLB, RefPicList eRefList 
#if REMOVE_MV_ADAPT_PREC
  , bool setHighPrec
#endif
)
{
  int width  = pu.Y().width;
  int shift = MAX_CU_DEPTH;
#if REMOVE_MV_ADAPT_PREC
  if (setHighPrec)
  {
    affLT.hor = affLT.hor << VCEG_AZ07_MV_ADD_PRECISION_BIT_FOR_STORE;
    affLT.ver = affLT.ver << VCEG_AZ07_MV_ADD_PRECISION_BIT_FOR_STORE;
    affRT.hor = affRT.hor << VCEG_AZ07_MV_ADD_PRECISION_BIT_FOR_STORE;
    affRT.ver = affRT.ver << VCEG_AZ07_MV_ADD_PRECISION_BIT_FOR_STORE;
    affLB.hor = affLB.hor << VCEG_AZ07_MV_ADD_PRECISION_BIT_FOR_STORE;
    affLB.ver = affLB.ver << VCEG_AZ07_MV_ADD_PRECISION_BIT_FOR_STORE;
  }
#else
  affLT.setHighPrec();
  affRT.setHighPrec();
  affLB.setHighPrec();
#endif
  int deltaMvHorX, deltaMvHorY, deltaMvVerX, deltaMvVerY;
  deltaMvHorX = (affRT - affLT).getHor() << (shift - g_aucLog2[width]);
  deltaMvHorY = (affRT - affLT).getVer() << (shift - g_aucLog2[width]);
  int height = pu.Y().height;
  if ( pu.cu->affineType == AFFINEMODEL_6PARAM )
  {
    deltaMvVerX = (affLB - affLT).getHor() << (shift - g_aucLog2[height]);
    deltaMvVerY = (affLB - affLT).getVer() << (shift - g_aucLog2[height]);
  }
  else
  {
    deltaMvVerX = -deltaMvHorY;
    deltaMvVerY = deltaMvHorX;
  }

  int mvScaleHor = affLT.getHor() << shift;
  int mvScaleVer = affLT.getVer() << shift;

  int blockWidth = AFFINE_MIN_BLOCK_SIZE;
  int blockHeight = AFFINE_MIN_BLOCK_SIZE;
  const int halfBW = blockWidth >> 1;
  const int halfBH = blockHeight >> 1;

  MotionBuf mb = pu.getMotionBuf();
  int mvScaleTmpHor, mvScaleTmpVer;
  for ( int h = 0; h < pu.Y().height; h += blockHeight )
  {
    for ( int w = 0; w < pu.Y().width; w += blockWidth )
    {
      mvScaleTmpHor = mvScaleHor + deltaMvHorX * (halfBW + w) + deltaMvVerX * (halfBH + h);
      mvScaleTmpVer = mvScaleVer + deltaMvHorY * (halfBW + w) + deltaMvVerY * (halfBH + h);
      roundAffineMv( mvScaleTmpHor, mvScaleTmpVer, shift );

      for ( int y = (h >> MIN_CU_LOG2); y < ((h + blockHeight) >> MIN_CU_LOG2); y++ )
      {
        for ( int x = (w >> MIN_CU_LOG2); x < ((w + blockHeight) >> MIN_CU_LOG2); x++ )
        {
#if REMOVE_MV_ADAPT_PREC
          mb.at(x, y).mv[eRefList].hor = mvScaleTmpHor;
          mb.at(x, y).mv[eRefList].ver = mvScaleTmpVer;
#else
          mb.at(x, y).mv[eRefList] = Mv(mvScaleTmpHor, mvScaleTmpVer, true);
#endif
        }
      }
    }
  }

  // Set AffineMvField for affine motion compensation LT, RT, LB and RB
  mb.at(            0,             0 ).mv[eRefList] = affLT;
  mb.at( mb.width - 1,             0 ).mv[eRefList] = affRT;

  if ( pu.cu->affineType == AFFINEMODEL_6PARAM )
  {
    mb.at( 0, mb.height - 1 ).mv[eRefList] = affLB;
  }
}

static bool deriveScaledMotionTemporal( const Slice&      slice,
                                        const Position&   colPos,
                                        const Picture*    pColPic,
                                        const RefPicList  eCurrRefPicList,
                                        Mv&         cColMv,
                                        const RefPicList  eFetchRefPicList)
{
  const MotionInfo &mi = pColPic->cs->getMotionInfo(colPos);
  const Slice *pColSlice = nullptr;

  for (const auto &pSlice : pColPic->slices)
  {
    if (pSlice->getIndependentSliceIdx() == mi.sliceIdx)
    {
      pColSlice = pSlice;
      break;
    }
  }

  CHECK(pColSlice == nullptr, "Couldn't find the colocated slice");

  int iColPOC, iColRefPOC, iCurrPOC, iCurrRefPOC, iScale;
  bool bAllowMirrorMV = true;
  RefPicList eColRefPicList = slice.getCheckLDC() ? eCurrRefPicList : RefPicList(1 - eFetchRefPicList);
  if (pColPic == slice.getRefPic(RefPicList(slice.isInterB() ? 1 - slice.getColFromL0Flag() : 0), slice.getColRefIdx()))
  {
    eColRefPicList = eCurrRefPicList;   //67 -> disable, 64 -> enable
    bAllowMirrorMV = false;
  }

  // Although it might make sense to keep the unavailable motion field per direction still be unavailable, I made the MV prediction the same way as in TMVP
  // So there is an interaction between MV0 and MV1 of the corresponding blocks identified by TV.

  // Grab motion and do necessary scaling.{{
  iCurrPOC = slice.getPOC();

  int iColRefIdx = mi.refIdx[eColRefPicList];

  if (iColRefIdx < 0 && (slice.getCheckLDC() || bAllowMirrorMV))
  {
    eColRefPicList = RefPicList(1 - eColRefPicList);
    iColRefIdx = mi.refIdx[eColRefPicList];

    if (iColRefIdx < 0)
    {
      return false;
    }
  }

  if (iColRefIdx >= 0 && slice.getNumRefIdx(eCurrRefPicList) > 0)
  {
    iColPOC = pColSlice->getPOC();
    iColRefPOC = pColSlice->getRefPOC(eColRefPicList, iColRefIdx);
    ///////////////////////////////////////////////////////////////
    // Set the target reference index to 0, may be changed later //
    ///////////////////////////////////////////////////////////////
    iCurrRefPOC = slice.getRefPic(eCurrRefPicList, 0)->getPOC();
    // Scale the vector.
    cColMv = mi.mv[eColRefPicList];
    //pcMvFieldSP[2*iPartition + eCurrRefPicList].getMv();
    // Assume always short-term for now
    iScale = xGetDistScaleFactor(iCurrPOC, iCurrRefPOC, iColPOC, iColRefPOC);

    if (iScale != 4096)
    {
#if !REMOVE_MV_ADAPT_PREC
      if (slice.getSPS()->getSpsNext().getUseHighPrecMv())
      {
        cColMv.setHighPrec();
      }
#endif

      cColMv = cColMv.scaleMv(iScale);
    }

    return true;
  }
  return false;
}

#if JVET_L0257_ATMVP_COLBLK_CLIP
void clipColPos(int& posX, int& posY, const PredictionUnit& pu)
{
  Position puPos = pu.lumaPos();
  int log2CtuSize = g_aucLog2[pu.cs->sps->getSpsNext().getCTUSize()];
  int ctuX = ((puPos.x >> log2CtuSize) << log2CtuSize);
  int ctuY = ((puPos.y >> log2CtuSize) << log2CtuSize);

  int horMax = std::min((int)pu.cs->sps->getPicWidthInLumaSamples() - 1, ctuX + (int)pu.cs->sps->getSpsNext().getCTUSize() + 3);
  int horMin = std::max((int)0, ctuX);
  int verMax = std::min((int)pu.cs->sps->getPicHeightInLumaSamples() - 1, ctuY + (int)pu.cs->sps->getSpsNext().getCTUSize() - 1);
  int verMin = std::max((int)0, ctuY);

  posX = std::min(horMax, std::max(horMin, posX));
  posY = std::min(verMax, std::max(verMin, posY));
}
#else
void clipColBlkMv(int& mvX, int& mvY, const PredictionUnit& pu)
{
  Position puPos = pu.lumaPos();
  Size     puSize = pu.lumaSize();

  int ctuSize = pu.cs->sps->getSpsNext().getCTUSize();
  int ctuX = puPos.x / ctuSize*ctuSize;
  int ctuY = puPos.y / ctuSize*ctuSize;

  int horMax = std::min((int)pu.cs->sps->getPicWidthInLumaSamples(), ctuX + ctuSize + 4) - puSize.width;
  int horMin = std::max((int)0, ctuX);
  int verMax = std::min((int)pu.cs->sps->getPicHeightInLumaSamples(), ctuY + ctuSize) - puSize.height;
  int verMin = std::min((int)0, ctuY);

  horMax = horMax - puPos.x;
  horMin = horMin - puPos.x;
  verMax = verMax - puPos.y;
  verMin = verMin - puPos.y;

  mvX = std::min(horMax, std::max(horMin, mvX));
  mvY = std::min(verMax, std::max(verMin, mvY));
}
#endif

bool PU::getInterMergeSubPuMvpCand(const PredictionUnit &pu, MergeCtx& mrgCtx, bool& LICFlag, const int count
#if JVET_L0054_MMVD
  , int mmvdList
#endif
)
{
  const Slice   &slice = *pu.cs->slice;
  const unsigned scale = 4 * std::max<int>(1, 4 * AMVP_DECIMATION_FACTOR / 4);
  const unsigned mask = ~(scale - 1);

  const Picture *pColPic = slice.getRefPic(RefPicList(slice.isInterB() ? 1 - slice.getColFromL0Flag() : 0), slice.getColRefIdx());
  Mv cTMv;
  RefPicList fetchRefPicList = RefPicList(slice.isInterB() ? 1 - slice.getColFromL0Flag() : 0);

  bool terminate = false;
  for (unsigned currRefListId = 0; currRefListId < (slice.getSliceType() == B_SLICE ? 2 : 1) && !terminate; currRefListId++)
  {
    for (int uiN = 0; uiN < count && !terminate; uiN++)
    {
      RefPicList currRefPicList = RefPicList(slice.getCheckLDC() ? (slice.getColFromL0Flag() ? currRefListId : 1 - currRefListId) : currRefListId);

      if ((mrgCtx.interDirNeighbours[uiN] & (1 << currRefPicList)) && slice.getRefPic(currRefPicList, mrgCtx.mvFieldNeighbours[uiN * 2 + currRefPicList].refIdx) == pColPic)
      {
        cTMv = mrgCtx.mvFieldNeighbours[uiN * 2 + currRefPicList].mv;
        terminate = true;
        fetchRefPicList = currRefPicList;
        break;
      }
    }
  }

  ///////////////////////////////////////////////////////////////////////
  ////////          GET Initial Temporal Vector                  ////////
  ///////////////////////////////////////////////////////////////////////
  int mvPrec = 2;
#if !REMOVE_MV_ADAPT_PREC
  if (pu.cs->sps->getSpsNext().getUseHighPrecMv())
  {
    cTMv.setHighPrec();
#endif
    mvPrec += VCEG_AZ07_MV_ADD_PRECISION_BIT_FOR_STORE;
#if !REMOVE_MV_ADAPT_PREC
  }
#endif
#if !JVET_L0257_ATMVP_COLBLK_CLIP
  int mvRndOffs = (1 << mvPrec) >> 1;
#endif

  Mv cTempVector = cTMv;
  bool  tempLICFlag = false;

  // compute the location of the current PU
  Position puPos = pu.lumaPos();
  Size puSize = pu.lumaSize();
  int numPartLine = std::max(puSize.width >> slice.getSubPuMvpSubblkLog2Size(), 1u);
  int numPartCol = std::max(puSize.height >> slice.getSubPuMvpSubblkLog2Size(), 1u);
  int puHeight = numPartCol == 1 ? puSize.height : 1 << slice.getSubPuMvpSubblkLog2Size();
  int puWidth = numPartLine == 1 ? puSize.width : 1 << slice.getSubPuMvpSubblkLog2Size();

  Mv cColMv;
  // use coldir.
  bool     bBSlice = slice.isInterB();

  Position centerPos;

  bool found = false;
  cTempVector = cTMv;
#if JVET_L0257_ATMVP_COLBLK_CLIP
  int tempX = cTempVector.getHor() >> mvPrec;
  int tempY = cTempVector.getVer() >> mvPrec;

  centerPos.x = puPos.x + (puSize.width >> 1) + tempX;
  centerPos.y = puPos.y + (puSize.height >> 1) + tempY;

  clipColPos(centerPos.x, centerPos.y, pu);
#else
  int tempX = ((cTempVector.getHor() + mvRndOffs) >> mvPrec);
  int tempY = ((cTempVector.getVer() + mvRndOffs) >> mvPrec);
  clipColBlkMv(tempX, tempY, pu);

  if (puSize.width == puWidth && puSize.height == puHeight)
  {
    centerPos.x = puPos.x + (puSize.width >> 1) + tempX;
    centerPos.y = puPos.y + (puSize.height >> 1) + tempY;
  }
  else
  {
    centerPos.x = puPos.x + ((puSize.width / puWidth) >> 1)   * puWidth + (puWidth >> 1) + tempX;
    centerPos.y = puPos.y + ((puSize.height / puHeight) >> 1) * puHeight + (puHeight >> 1) + tempY;
  }

  centerPos.x = Clip3(0, (int)pColPic->lwidth() - 1, centerPos.x);
  centerPos.y = Clip3(0, (int)pColPic->lheight() - 1, centerPos.y);
#endif

  centerPos = Position{ PosType(centerPos.x & mask), PosType(centerPos.y & mask) };

  // derivation of center motion parameters from the collocated CU
  const MotionInfo &mi = pColPic->cs->getMotionInfo(centerPos);

  if (mi.isInter)
  {
    for (unsigned currRefListId = 0; currRefListId < (bBSlice ? 2 : 1); currRefListId++)
    {
      RefPicList  currRefPicList = RefPicList(currRefListId);

      if (deriveScaledMotionTemporal(slice, centerPos, pColPic, currRefPicList, cColMv, fetchRefPicList))
      {
        // set as default, for further motion vector field spanning
        mrgCtx.mvFieldNeighbours[(count << 1) + currRefListId].setMvField(cColMv, 0);
        mrgCtx.interDirNeighbours[count] |= (1 << currRefListId);
        LICFlag = tempLICFlag;
#if JVET_L0646_GBI
        mrgCtx.GBiIdx[count] = GBI_DEFAULT;
#endif
        found = true;
      }
      else
      {
        mrgCtx.mvFieldNeighbours[(count << 1) + currRefListId].setMvField(Mv(), NOT_VALID);
        mrgCtx.interDirNeighbours[count] &= ~(1 << currRefListId);
      }
    }
  }

  if (!found)
  {
    return false;
  }
#if JVET_L0054_MMVD
  if (mmvdList != 1)
  {
#endif
#if JVET_L0257_ATMVP_COLBLK_CLIP
  int xOff = (puWidth >> 1) + tempX;
  int yOff = (puHeight >> 1) + tempY;
#else
  int xOff = puWidth / 2;
  int yOff = puHeight / 2;

  // compute the location of the current PU
  xOff += tempX;
  yOff += tempY;

  int iPicWidth = pColPic->lwidth() - 1;
  int iPicHeight = pColPic->lheight() - 1;
#endif

  MotionBuf& mb = mrgCtx.subPuMvpMiBuf;

  const bool isBiPred = isBipredRestriction(pu);

  for (int y = puPos.y; y < puPos.y + puSize.height; y += puHeight)
  {
    for (int x = puPos.x; x < puPos.x + puSize.width; x += puWidth)
    {
      Position colPos{ x + xOff, y + yOff };

#if JVET_L0257_ATMVP_COLBLK_CLIP
      clipColPos(colPos.x, colPos.y, pu);
#else
      colPos.x = Clip3(0, iPicWidth, colPos.x);
      colPos.y = Clip3(0, iPicHeight, colPos.y);
#endif

      colPos = Position{ PosType(colPos.x & mask), PosType(colPos.y & mask) };

      const MotionInfo &colMi = pColPic->cs->getMotionInfo(colPos);

      MotionInfo mi;

      mi.isInter = true;
      mi.sliceIdx = slice.getIndependentSliceIdx();

      if (colMi.isInter)
      {
        for (unsigned currRefListId = 0; currRefListId < (bBSlice ? 2 : 1); currRefListId++)
        {
          RefPicList currRefPicList = RefPicList(currRefListId);
          if (deriveScaledMotionTemporal(slice, colPos, pColPic, currRefPicList, cColMv, fetchRefPicList))
          {
            mi.refIdx[currRefListId] = 0;
            mi.mv[currRefListId] = cColMv;
          }
        }
        }
      else
      {
        // intra coded, in this case, no motion vector is available for list 0 or list 1, so use default
        mi.mv[0] = mrgCtx.mvFieldNeighbours[(count << 1) + 0].mv;
        mi.mv[1] = mrgCtx.mvFieldNeighbours[(count << 1) + 1].mv;
        mi.refIdx[0] = mrgCtx.mvFieldNeighbours[(count << 1) + 0].refIdx;
        mi.refIdx[1] = mrgCtx.mvFieldNeighbours[(count << 1) + 1].refIdx;
      }

      mi.interDir = (mi.refIdx[0] != -1 ? 1 : 0) + (mi.refIdx[1] != -1 ? 2 : 0);

      if (isBiPred && mi.interDir == 3)
      {
        mi.interDir = 1;
        mi.mv[1] = Mv();
        mi.refIdx[1] = NOT_VALID;
      }

      mb.subBuf(g_miScaling.scale(Position{ x, y } -pu.lumaPos()), g_miScaling.scale(Size(puWidth, puHeight))).fill(mi);
      }
    }
#if JVET_L0054_MMVD
  }
#endif
  return true;
  }

void PU::spanMotionInfo( PredictionUnit &pu, const MergeCtx &mrgCtx )
{
  MotionBuf mb = pu.getMotionBuf();

  if( !pu.mergeFlag || pu.mergeType == MRG_TYPE_DEFAULT_N )
  {
    MotionInfo mi;

    mi.isInter  = CU::isInter( *pu.cu );
    mi.sliceIdx = pu.cu->slice->getIndependentSliceIdx();

    if( mi.isInter )
    {
      mi.interDir = pu.interDir;

      for( int i = 0; i < NUM_REF_PIC_LIST_01; i++ )
      {
        mi.mv[i]     = pu.mv[i];
        mi.refIdx[i] = pu.refIdx[i];
      }
    }

    if( pu.cu->affine )
    {
      for( int y = 0; y < mb.height; y++ )
      {
        for( int x = 0; x < mb.width; x++ )
        {
          MotionInfo &dest = mb.at( x, y );
          dest.isInter  = mi.isInter;
          dest.interDir = mi.interDir;
          dest.sliceIdx = mi.sliceIdx;
          for( int i = 0; i < NUM_REF_PIC_LIST_01; i++ )
          {
            if( mi.refIdx[i] == -1 )
            {
              dest.mv[i] = Mv();
            }
            dest.refIdx[i] = mi.refIdx[i];
          }
        }
      }
    }
    else
    {
      mb.fill( mi );
    }
  }
  else if (pu.mergeType == MRG_TYPE_SUBPU_ATMVP)
  {
    CHECK(mrgCtx.subPuMvpMiBuf.area() == 0 || !mrgCtx.subPuMvpMiBuf.buf, "Buffer not initialized");
    mb.copyFrom(mrgCtx.subPuMvpMiBuf);
  }
  else
  {

    if( isBipredRestriction( pu ) )
    {
      for( int y = 0; y < mb.height; y++ )
      {
        for( int x = 0; x < mb.width; x++ )
        {
          MotionInfo &mi = mb.at( x, y );
          if( mi.interDir == 3 )
          {
            mi.interDir  = 1;
            mi.mv    [1] = Mv();
            mi.refIdx[1] = NOT_VALID;
          }
        }
      }
    }
  }
}

void PU::applyImv( PredictionUnit& pu, MergeCtx &mrgCtx, InterPrediction *interPred )
{
  if( !pu.mergeFlag )
  {
    unsigned imvShift = pu.cu->imv << 1;
    if( pu.interDir != 2 /* PRED_L1 */ )
    {
      if (pu.cu->imv)
      {
#if !REMOVE_MV_ADAPT_PREC
        CHECK(pu.mvd[0].highPrec, "Motion vector difference should never be high precision");
#endif
        pu.mvd[0] = Mv( pu.mvd[0].hor << imvShift, pu.mvd[0].ver << imvShift );
      }
      unsigned mvp_idx = pu.mvpIdx[0];
      AMVPInfo amvpInfo;
      PU::fillMvpCand(pu, REF_PIC_LIST_0, pu.refIdx[0], amvpInfo);
      pu.mvpNum[0] = amvpInfo.numCand;
      pu.mvpIdx[0] = mvp_idx;
      pu.mv    [0] = amvpInfo.mvCand[mvp_idx] + pu.mvd[0];
#if REMOVE_MV_ADAPT_PREC
      pu.mv[0].hor = pu.mv[0].hor << VCEG_AZ07_MV_ADD_PRECISION_BIT_FOR_STORE;
      pu.mv[0].ver = pu.mv[0].ver << VCEG_AZ07_MV_ADD_PRECISION_BIT_FOR_STORE;
#endif
    }

    if (pu.interDir != 1 /* PRED_L0 */)
    {
      if( !( pu.cu->cs->slice->getMvdL1ZeroFlag() && pu.interDir == 3 ) && pu.cu->imv )/* PRED_BI */
      {
#if !REMOVE_MV_ADAPT_PREC
        CHECK(pu.mvd[1].highPrec, "Motion vector difference should never be high precision");
#endif
        pu.mvd[1] = Mv( pu.mvd[1].hor << imvShift, pu.mvd[1].ver << imvShift );
      }
      unsigned mvp_idx = pu.mvpIdx[1];
      AMVPInfo amvpInfo;
      PU::fillMvpCand(pu, REF_PIC_LIST_1, pu.refIdx[1], amvpInfo);
      pu.mvpNum[1] = amvpInfo.numCand;
      pu.mvpIdx[1] = mvp_idx;
      pu.mv    [1] = amvpInfo.mvCand[mvp_idx] + pu.mvd[1];
#if REMOVE_MV_ADAPT_PREC
      pu.mv[1].hor = pu.mv[1].hor << VCEG_AZ07_MV_ADD_PRECISION_BIT_FOR_STORE;
      pu.mv[1].ver = pu.mv[1].ver << VCEG_AZ07_MV_ADD_PRECISION_BIT_FOR_STORE;
#endif
    }
  }
  else
  {
    // this function is never called for merge
    THROW("unexpected");
    PU::getInterMergeCandidates ( pu, mrgCtx 
#if JVET_L0054_MMVD
      , 0
#endif
    );
    PU::restrictBiPredMergeCands( pu, mrgCtx );

    mrgCtx.setMergeInfo( pu, pu.mergeIdx );
  }

  PU::spanMotionInfo( pu, mrgCtx );
}

bool PU::isBiPredFromDifferentDir( const PredictionUnit& pu )
{
  if ( pu.refIdx[0] >= 0 && pu.refIdx[1] >= 0 )
  {
    const int iPOC0 = pu.cu->slice->getRefPOC( REF_PIC_LIST_0, pu.refIdx[0] );
    const int iPOC1 = pu.cu->slice->getRefPOC( REF_PIC_LIST_1, pu.refIdx[1] );
    const int iPOC  = pu.cu->slice->getPOC();
    if ( (iPOC - iPOC0)*(iPOC - iPOC1) < 0 )
    {
      return true;
    }
  }

  return false;
}

void PU::restrictBiPredMergeCands( const PredictionUnit &pu, MergeCtx& mergeCtx )
{
  if( PU::isBipredRestriction( pu ) )
  {
    for( uint32_t mergeCand = 0; mergeCand < mergeCtx.numValidMergeCand; ++mergeCand )
    {
      if( mergeCtx.interDirNeighbours[ mergeCand ] == 3 )
      {
        mergeCtx.interDirNeighbours[ mergeCand ] = 1;
        mergeCtx.mvFieldNeighbours[( mergeCand << 1 ) + 1].setMvField( Mv( 0, 0 ), -1 );
#if JVET_L0646_GBI
        mergeCtx.GBiIdx[mergeCand] = GBI_DEFAULT;
#endif
      }
    }
  }
}

void CU::resetMVDandMV2Int( CodingUnit& cu, InterPrediction *interPred )
{
  for( auto &pu : CU::traversePUs( cu ) )
  {
    MergeCtx mrgCtx;

    if( !pu.mergeFlag )
    {
      unsigned imvShift = cu.imv << 1;
      if( pu.interDir != 2 /* PRED_L1 */ )
      {
        Mv mv        = pu.mv[0];
        Mv mvPred;
        AMVPInfo amvpInfo;
        PU::fillMvpCand(pu, REF_PIC_LIST_0, pu.refIdx[0], amvpInfo);
        pu.mvpNum[0] = amvpInfo.numCand;

        mvPred       = amvpInfo.mvCand[pu.mvpIdx[0]];
        roundMV      ( mv, imvShift );
        pu.mv[0]     = mv;
        Mv mvDiff    = mv - mvPred;
        pu.mvd[0]    = mvDiff;
      }
      if( pu.interDir != 1 /* PRED_L0 */ )
      {
        Mv mv        = pu.mv[1];
        Mv mvPred;
        AMVPInfo amvpInfo;
        PU::fillMvpCand(pu, REF_PIC_LIST_1, pu.refIdx[1], amvpInfo);
        pu.mvpNum[1] = amvpInfo.numCand;

        mvPred       = amvpInfo.mvCand[pu.mvpIdx[1]];
        roundMV      ( mv, imvShift );
        Mv mvDiff    = mv - mvPred;

        if( pu.cu->cs->slice->getMvdL1ZeroFlag() && pu.interDir == 3 /* PRED_BI */ )
        {
          pu.mvd[1] = Mv();
          mv = mvPred;
        }
        else
        {
          pu.mvd[1] = mvDiff;
        }
        pu.mv[1] = mv;
      }

    }