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/** \file     DecCu.cpp

    \brief    CU decoder class

*/

#include "DecCu.h"

#include "CommonLib/InterPrediction.h"

#include "CommonLib/IntraPrediction.h"

#include "CommonLib/Picture.h"

#include "CommonLib/UnitTools.h"

#include "CommonLib/LoopFilter.h"

#include "CommonLib/dtrace_buffer.h"

//! \ingroup DecoderLib

//! \{

namespace vvenc {

// ====================================================================================================================

// Constructor / destructor / create / destroy

// ====================================================================================================================

DecCu::DecCu()

{

}

DecCu::~DecCu()

{

  m_TmpBuffer.destroy();

  m_PredBuffer.destroy();

}

void DecCu::init( TrQuant* pcTrQuant, IntraPrediction* pcIntra, InterPrediction* pcInter, ChromaFormat chrFormat)

{

  m_pcTrQuant       = pcTrQuant;

  m_pcIntraPred     = pcIntra;

  m_pcInterPred     = pcInter;

  m_TmpBuffer.destroy();

  m_TmpBuffer.create( chrFormat, Area( 0,0, MAX_TB_SIZEY, MAX_TB_SIZEY ));

  m_PredBuffer.destroy();

  m_PredBuffer.create( chrFormat, Area( 0,0, MAX_CU_SIZE, MAX_CU_SIZE ));

}

// ====================================================================================================================

// Protected member functions

// ====================================================================================================================

void DecCu::xIntraRecBlk( TransformUnit& tu, const ComponentID compID )

{

  if( !tu.blocks[ compID ].valid() )

  {

    return;

  }

        CodingStructure &cs     = *tu.cs;

  const CompArea& area          = tu.blocks[compID];

  const ChannelType chType      = toChannelType( compID );

  PelBuf piPred                 = tu.cu->ispMode && isLuma( compID ) ? cs.getPredBuf( area ) : m_PredBuffer.getCompactBuf( area );

  const CodingUnit& cu          = *tu.cu;

  const uint32_t uiChFinalMode  = CU::getFinalIntraMode( cu, chType );

  PelBuf pReco                  = cs.getRecoBuf( area );

  //===== init availability pattern =====

  CompArea areaPredReg(COMP_Y, tu.chromaFormat, area);

  bool predRegDiffFromTB = isLuma( compID ) && CU::isPredRegDiffFromTB( *tu.cu );

  bool firstTBInPredReg  = isLuma( compID ) && CU::isFirstTBInPredReg ( *tu.cu, area );

  if( tu.cu->ispMode && isLuma( compID ) )

  {

    if( predRegDiffFromTB )

    {

      if( firstTBInPredReg )

      {

        CU::adjustPredArea( areaPredReg );

        m_pcIntraPred->initIntraPatternChTypeISP( *tu.cu, areaPredReg, pReco );

      }

    }

    else

    {

      m_pcIntraPred->initIntraPatternChTypeISP( *tu.cu, area, pReco );

    }

  }

  else

  {

    m_pcIntraPred->initIntraPatternChType( *tu.cu, area );

  }

  //===== get prediction signal =====

  if( compID != COMP_Y && CU::isLMCMode( uiChFinalMode ) )

  {

    const CodingUnit& cu = *tu.cu;

    m_pcIntraPred->loadLMLumaRecPels( cu, area );

    m_pcIntraPred->predIntraChromaLM( compID, piPred, cu, area, uiChFinalMode );

  }

  else if( CU::isMIP( cu, chType ) )

  {

    m_pcIntraPred->initIntraMip( cu );

    m_pcIntraPred->predIntraMip( piPred, cu );

  }

  else

  {

    if (predRegDiffFromTB)

    {

      if (firstTBInPredReg)

      {

        PelBuf piPredReg = cs.getPredBuf(areaPredReg);

        m_pcIntraPred->predIntraAng(compID, piPredReg, cu);

      }

    }

    else

    {

      m_pcIntraPred->predIntraAng(compID, piPred, cu);

    }

  }

  //===== inverse transform =====

  PelBuf piResi = cs.getResiBuf( area );

  const QpParam cQP( tu, compID );

  if( tu.jointCbCr && isChroma(compID) )

  {

    if( compID == COMP_Cb )

    {

      PelBuf resiCr = cs.getResiBuf( tu.blocks[ COMP_Cr ] );

      if( tu.jointCbCr >> 1 )

      {

        m_pcTrQuant->invTransformNxN( tu, COMP_Cb, piResi, cQP );

      }

      else

      {

        const QpParam qpCr( tu, COMP_Cr );

        m_pcTrQuant->invTransformNxN( tu, COMP_Cr, resiCr, qpCr );

      }

      m_pcTrQuant->invTransformICT( tu, piResi, resiCr );

    }

  }

  else

  if( TU::getCbf( tu, compID ) )

  {

    m_pcTrQuant->invTransformNxN( tu, compID, piResi, cQP );

  }

  else

  {

    piResi.fill( 0 );

  }

  //===== reconstruction =====

  piPred.reconstruct( piPred, piResi, tu.cu->cs->slice->clpRngs[ compID ] );

  pReco.copyFrom( piPred );

  if( true/*isEncoder*/ )

  {

    cs.picture->getRecoBuf( area ).copyFrom( pReco );

  }

}

void DecCu::xReconIntraQT( CodingUnit &cu )

{

  const uint32_t numChType = getNumberValidChannels( cu.chromaFormat );

  for( uint32_t chType = CH_L; chType < numChType; chType++ )

  {

    if( cu.blocks[chType].valid() )

    {

      xIntraRecQT( cu, ChannelType( chType ) );

    }

  }

}

/** Function for deriving reconstructed PU/CU chroma samples with QTree structure

* \param pcRecoYuv pointer to reconstructed sample arrays

* \param pcPredYuv pointer to prediction sample arrays

* \param pcResiYuv pointer to residue sample arrays

* \param chType    texture channel type (luma/chroma)

* \param rTu       reference to transform data

*

\ This function derives reconstructed PU/CU chroma samples with QTree recursive structure

*/

void DecCu::xIntraRecQT(CodingUnit &cu, const ChannelType chType)

{

  for( auto &currTU : CU::traverseTUs( cu ) )

  {

    if( isLuma( chType ) )

    {

      xIntraRecBlk( currTU, COMP_Y );

    }

    else

    {

      const uint32_t numValidComp = getNumberValidComponents( cu.chromaFormat );

      for( uint32_t compID = COMP_Cb; compID < numValidComp; compID++ )

      {

        xIntraRecBlk( currTU, ComponentID( compID ) );

      }

    }

  }

}

void DecCu::xReconInter( CodingUnit &cu )

{

  CodingStructure &cs = *cu.cs;

  PelUnitBuf predBuf = m_PredBuffer.getCompactBuf( cu ); 

  if (cu.geo)

  {

    m_pcInterPred->motionCompensationGeo(cu, predBuf, m_geoMrgCtx);

    CU::spanGeoMotionInfo(cu, m_geoMrgCtx, cu.geoSplitDir, cu.geoMergeIdx[0], cu.geoMergeIdx[1]);

  }

  else

  {

    CHECK(CU::isIBC(cu) && cu.ciip, "IBC and Ciip cannot be used together");

    CHECK(CU::isIBC(cu) && cu.affine, "IBC and Affine cannot be used together");

    CHECK(CU::isIBC(cu) && cu.geo, "IBC and geo cannot be used together");

    CHECK(CU::isIBC(cu) && cu.mmvdMergeFlag, "IBC and MMVD cannot be used together");

    const bool luma   = cu.Y().valid();

    const bool chroma = isChromaEnabled( cu.chromaFormat ) && cu.Cb().valid();

    if( luma && ( chroma || !isChromaEnabled( cu.chromaFormat ) ) )

    {

      cu.mvRefine = true;

      m_pcInterPred->motionCompensation(cu, predBuf);

      cu.mvRefine = false;

    }

    else

    {

      cu.mcControl  = luma   ? 0 : 4;

      cu.mcControl |= chroma ? 0 : 2;

      m_pcInterPred->motionCompensationIBC(cu, predBuf);

      cu.mcControl  = 0;

    }

    if( cu.Y().valid() )

    {

      bool isIbcSmallBlk = CU::isIBC( cu ) && ( cu.lwidth() * cu.lheight() <= 16 );

      //CU::saveMotionInHMVP(cu, isIbcSmallBlk);

      if( !cu.affine && !cu.geo && !isIbcSmallBlk )

      {

        const MotionInfo &mi = cu.getMotionInfo();

        HPMVInfo hMi( mi, ( mi.interDir() == 3 ) ? cu.BcwIdx : BCW_DEFAULT, cu.imv == IMV_HPEL, CU::isIBC( cu ) );

        cs.addMiToLut( CU::isIBC( cu ) ? cu.cs->motionLut.lutIbc : cu.cs->motionLut.lut, hMi );

      }

    }

    if (cu.ciip)

    {

      PelBuf ciipBuf = m_TmpBuffer.getCompactBuf( cu.Y() );

      m_pcIntraPred->initIntraPatternChType(cu, cu.Y());

      m_pcIntraPred->predIntraAng(COMP_Y, ciipBuf, cu);

      const int numCiipIntra = m_pcIntraPred->getNumIntraCiip( cu );

      predBuf.Y().weightCiip( ciipBuf, numCiipIntra);

      if (isChromaEnabled(cu.chromaFormat) && cu.chromaSize().width > 2)

      {

        PelBuf ciipBufC = m_TmpBuffer.getCompactBuf( cu.Cb() );

        m_pcIntraPred->initIntraPatternChType(cu, cu.Cb());

        m_pcIntraPred->predIntraAng(COMP_Cb, ciipBufC, cu);

        predBuf.Cb().weightCiip( ciipBufC, numCiipIntra);

        m_pcIntraPred->initIntraPatternChType(cu, cu.Cr());

        m_pcIntraPred->predIntraAng(COMP_Cr, ciipBufC, cu);

        predBuf.Cr().weightCiip( ciipBufC, numCiipIntra);

      }

    }

  }

  // inter recon

  xDecodeInterTexture(cu);

  bool LumaOnly = ((predBuf.bufs.size() > 1) && (predBuf.bufs[1].stride != 0 && predBuf.bufs[2].stride != 0) ) ? false : true;

  if (cu.rootCbf)

  {

    if (LumaOnly)

    {

      cs.getResiBuf(cu.Y()).reconstruct(predBuf.Y(), cs.getResiBuf(cu.Y()), cs.slice->clpRngs[COMP_Y]);

      cs.getRecoBuf(cu.Y()).copyFrom(cs.getResiBuf(cu.Y()));

    }

    else

    {

      cs.getResiBuf(cu).reconstruct(predBuf, cs.getResiBuf(cu), cs.slice->clpRngs);

      cs.getRecoBuf(cu).copyFrom(cs.getResiBuf(cu));

    }

  }

  else

  {

    if (LumaOnly)

    {

      cs.getRecoBuf(cu.Y()).copyClip(predBuf.Y(), cs.slice->clpRngs[COMP_Y]);

    }

    else

    {

      cs.getRecoBuf(cu).copyClip(predBuf, cs.slice->clpRngs);

    }

  }

}

void DecCu::xDecodeInterTU( TransformUnit&  currTU, const ComponentID compID )

{

  if( !currTU.blocks[compID].valid() ) return;

  const CompArea& area = currTU.blocks[compID];

  CodingStructure& cs = *currTU.cs;

  //===== inverse transform =====

  PelBuf resiBuf  = cs.getResiBuf(area);

  const QpParam cQP(currTU, compID);

  if( currTU.jointCbCr && isChroma(compID) )

  {

    if( compID == COMP_Cb )

    {

      PelBuf resiCr = cs.getResiBuf( currTU.blocks[ COMP_Cr ] );

      if( currTU.jointCbCr >> 1 )

      {

        m_pcTrQuant->invTransformNxN( currTU, COMP_Cb, resiBuf, cQP );

      }

      else

      {

        const QpParam qpCr( currTU, COMP_Cr );

        m_pcTrQuant->invTransformNxN( currTU, COMP_Cr, resiCr, qpCr );

      }

      m_pcTrQuant->invTransformICT( currTU, resiBuf, resiCr );

    }

  }

  else

  if( TU::getCbf( currTU, compID ) )

  {

    m_pcTrQuant->invTransformNxN( currTU, compID, resiBuf, cQP );

  }

  else

  {

    resiBuf.fill( 0 );

  }

}

void DecCu::xDecodeInterTexture(CodingUnit &cu)

{

  if( !cu.rootCbf )

  {

    return;

  }

  const uint32_t uiNumVaildComp = getNumberValidComponents(cu.chromaFormat);

  for (uint32_t ch = 0; ch < uiNumVaildComp; ch++)

  {

    const ComponentID compID = ComponentID(ch);

    for( auto& currTU : CU::traverseTUs( cu ) )

    {

      xDecodeInterTU( currTU, compID );

    }

  }

}

void DecCu::xDeriveCUMV( CodingUnit &cu )

{

  if( cu.mergeFlag )

  {

    MergeCtx mrgCtx;

    if (cu.mmvdMergeFlag || cu.mmvdSkip)

    {

      CHECK( cu.ciip, "invalid CIIP" );

      CU::getInterMergeCandidates    ( cu, mrgCtx, 1,  cu.mmvdMergeIdx.pos.baseIdx + 1 );

      CU::getInterMMVDMergeCandidates( cu, mrgCtx );

      mrgCtx.setMmvdMergeCandiInfo   ( cu, cu.mmvdMergeIdx );

      CU::spanMotionInfo             ( cu );

    }

    else

    {

      if (cu.geo)

      {

        CU::getGeoMergeCandidates(cu, m_geoMrgCtx);

      }

      else

      {

        AffineMergeCtx affineMergeCtx;

        if (cu.affine)

        {

          if (cu.cs->sps->SbtMvp)

          {

            Size bufSize                  = g_miScaling.scale(cu.lumaSize());

            affineMergeCtx.subPuMvpMiBuf  = MotionBuf(m_subPuMiBuf, bufSize);

          }

          CU::getAffineMergeCand(cu, affineMergeCtx, cu.mergeIdx);

          cu.interDir           =    affineMergeCtx.interDirNeighbours[cu.mergeIdx];

          cu.affineType         =    affineMergeCtx.affineType        [cu.mergeIdx];

          cu.BcwIdx             =    affineMergeCtx.BcwIdx            [cu.mergeIdx];

          cu.mergeType          =    affineMergeCtx.mergeType         [cu.mergeIdx];

          if (cu.mergeType == MRG_TYPE_SUBPU_ATMVP)

          {

            cu.refIdx[0] = affineMergeCtx.mvFieldNeighbours[cu.mergeIdx][0][0].refIdx;

            cu.refIdx[1] = affineMergeCtx.mvFieldNeighbours[cu.mergeIdx][1][0].refIdx;

          }

          else

          {

            for (int i = 0; i < 2; ++i)

            {

              if (cu.cs->slice->numRefIdx[RefPicList(i)] > 0)

              {

                MvField *mvField = affineMergeCtx.mvFieldNeighbours[cu.mergeIdx][i];

                cu.mvpIdx[i]     = 0;

                cu.mvpNum[i]     = 0;

                cu.mvd[i][0]     = Mv();

                CU::setAllAffineMvField(cu, mvField, RefPicList(i));

              }

            }

          }

        }

        else

        {

          if (CU::isIBC(cu))

          {

            CU::getIBCMergeCandidates(cu, mrgCtx, cu.mergeIdx);

          }

          else

          {

            CU::getInterMergeCandidates(cu, mrgCtx, 0, cu.mergeIdx);

          }

          mrgCtx.setMergeInfo(cu, cu.mergeIdx);

        }

        CU::spanMotionInfo(cu, &affineMergeCtx);

      }

    }

  } 

  else

  {

    if (cu.affine)

    {

      for (uint32_t uiRefListIdx = 0; uiRefListIdx < 2; uiRefListIdx++)

      {

        RefPicList eRefList = RefPicList(uiRefListIdx);

        if (cu.cs->slice->numRefIdx[eRefList] > 0 && (cu.interDir & (1 << uiRefListIdx)))

        {

          AffineAMVPInfo affineAMVPInfo;

          CU::fillAffineMvpCand(cu, eRefList, cu.refIdx[eRefList], affineAMVPInfo);

          const unsigned mvp_idx = cu.mvpIdx[eRefList];

          cu.mvpNum[eRefList] = affineAMVPInfo.numCand;

          //    Mv mv[3];

          CHECK(cu.refIdx[eRefList] < 0, "Unexpected negative refIdx.");

          if (!true/*isEncoder*/)

          {

            cu.mvd[eRefList][0].changeAffinePrecAmvr2Internal(cu.imv);

            cu.mvd[eRefList][1].changeAffinePrecAmvr2Internal(cu.imv);

            if (cu.affineType == AFFINEMODEL_6PARAM)

            {

              cu.mvd[eRefList][2].changeAffinePrecAmvr2Internal(cu.imv);

            }

          }

          Mv mvLT = affineAMVPInfo.mvCandLT[mvp_idx] + cu.mvd[eRefList][0];

          Mv mvRT = affineAMVPInfo.mvCandRT[mvp_idx] + cu.mvd[eRefList][1];

          mvRT += cu.mvd[eRefList][0];

          Mv mvLB;

          if (cu.affineType == AFFINEMODEL_6PARAM)

          {

            mvLB = affineAMVPInfo.mvCandLB[mvp_idx] + cu.mvd[eRefList][2];

            mvLB += cu.mvd[eRefList][0];

          }

          CU::setAllAffineMv(cu, mvLT, mvRT, mvLB, eRefList, true);

        }

      }

    }

    else if (CU::isIBC(cu) && cu.interDir == 1)

    {

      AMVPInfo amvpInfo;

      CU::fillIBCMvpCand(cu, amvpInfo);

      cu.mvpNum[REF_PIC_LIST_0] = amvpInfo.numCand;

      Mv mvd = cu.mvd[REF_PIC_LIST_0][0];

      if (!true/*isEncoder*/)

      {

        mvd.changeIbcPrecAmvr2Internal(cu.imv);

      }

      if (cu.cs->sps->maxNumIBCMergeCand == 1)

      {

        CHECK(cu.mvpIdx[REF_PIC_LIST_0], "mvpIdx for IBC mode should be 0");

      }

      cu.mv[REF_PIC_LIST_0][0] = amvpInfo.mvCand[cu.mvpIdx[REF_PIC_LIST_0]] + mvd;

      cu.mv[REF_PIC_LIST_0][0].mvCliptoStorageBitDepth();

    }

    else

    {

      for ( uint32_t uiRefListIdx = 0; uiRefListIdx < 2; uiRefListIdx++ )

      {

        RefPicList eRefList = RefPicList( uiRefListIdx );

        if ((cu.cs->slice->numRefIdx[eRefList] > 0 || (eRefList == REF_PIC_LIST_0 && CU::isIBC(cu))) && (cu.interDir & (1 << uiRefListIdx)))

        {

          AMVPInfo amvpInfo;

          CU::fillMvpCand(cu, eRefList, cu.refIdx[eRefList], amvpInfo);

          cu.mvpNum [eRefList] = amvpInfo.numCand;

          if (!true/*isEncoder*/)

          {

            cu.mvd[eRefList][0].changeTransPrecAmvr2Internal(cu.imv);

          }

          cu.mv[eRefList][0] = amvpInfo.mvCand[cu.mvpIdx[eRefList]] + cu.mvd[eRefList][0];

          cu.mv[eRefList][0].mvCliptoStorageBitDepth();

        }

      }

    }

    CU::spanMotionInfo( cu );

  }

  if (CU::isIBC(cu)) //only check

  {

    const int cuPelX = cu.Y().x;

    const int cuPelY = cu.Y().y;

    int roiWidth = cu.lwidth();

    int roiHeight = cu.lheight();

    const unsigned int  lcuWidth = cu.cs->slice->sps->CTUSize;

    int xPred = cu.mv[0][0].hor >> MV_FRACTIONAL_BITS_INTERNAL;

    int yPred = cu.mv[0][0].ver >> MV_FRACTIONAL_BITS_INTERNAL;

    CHECK(!m_pcInterPred->isLumaBvValidIBC(lcuWidth, cuPelX, cuPelY, roiWidth, roiHeight, xPred, yPred), "invalid block vector for IBC detected.");

  }

}

} // namespace vvenc

//! \}