IntraSearch.cpp

        }
        // both have the same number of subpartitions
        else if (numSubPartsBestMode2OtherSplit == numSubPartsBestMode2)
        {
          // both have the maximum number of subpartitions, so it compares RD costs to decide
          if (numSubPartsBestMode2OtherSplit == maxNumSubPartitions)
          {
            double rdCostBestMode2ThisSplit = ispTestedModes.getRDCost(nextISPcandSplitType, mode2);
            double rdCostBestMode2OtherSplit = ispTestedModes.getRDCost(otherSplit, mode2);
            double threshold = 1.3;
            if (rdCostBestMode2ThisSplit == MAX_DOUBLE || rdCostBestMode2OtherSplit < rdCostBestMode2ThisSplit * threshold)
            {
              stopThisSplit = true;
            }
          }
          else // none of them reached the maximum number of subpartitions with the best angle modes, so it compares the results with the the planar mode
          {
            int  numSubPartsBestMode1OtherSplit = mode1 != -1 ? ispTestedModes.getNumCompletedSubParts(otherSplit, mode1) : -1;
            if (numSubPartsBestMode1OtherSplit != -1 && numSubPartsBestMode1 != -1 && numSubPartsBestMode1OtherSplit > numSubPartsBestMode1)
            {
              stopThisSplit = true;
            }
          }
        }
      }
    }
    if (stopThisSplit)
    {
      ispTestedModes.splitIsFinished[nextISPcandSplitType - 1] = true;
      if (stopThisSplitForAllLFNSTs)
      {
        for (int lfnstIdx = 1; lfnstIdx < NUM_LFNST_NUM_PER_SET; lfnstIdx++)
        {
          m_ispTestedModes[lfnstIdx].splitIsFinished[nextISPcandSplitType - 1] = true;
        }
      }
      return;
    }
  }

  // Now a new mode is retrieved from the list and it has to be decided whether it should be tested or not
  if (ispTestedModes.candIndexInList[nextISPcandSplitType - 1] < rdModeLists[nextISPcandSplitType - 1]->size())
  {
    ModeInfo candidate = rdModeLists[nextISPcandSplitType - 1]->at(ispTestedModes.candIndexInList[nextISPcandSplitType - 1]);
    ispTestedModes.candIndexInList[nextISPcandSplitType - 1]++;

    // extra modes are only tested if ISP has won so far
    if (ispTestedModes.candIndexInList[nextISPcandSplitType - 1] > ispTestedModes.numOrigModesToTest)
    {
      if (ispTestedModes.bestSplitSoFar != candidate.ispMod || ispTestedModes.bestModeSoFar == PLANAR_IDX)
      {
        ispTestedModes.splitIsFinished[nextISPcandSplitType - 1] = true;
        return;
      }
    }

    bool testCandidate = true;

    // we look for a reference mode that has already been tested within the window and decide to test the new one according to the reference mode costs
    if (
#if ENABLE_DIMD && !JVET_V0087_DIMD_NO_ISP
      candidate.modeId != DIMD_IDX &&
#endif
#if JVET_W0123_TIMD_FUSION
      candidate.modeId != TIMD_IDX &&
#endif
      maxNumSubPartitions > 2 && (curIspLfnstIdx > 0 || (candidate.modeId >= DC_IDX && ispTestedModes.numTestedModes[nextISPcandSplitType - 1] >= 2)))
    {
      int       refLfnstIdx = -1;
      const int angWindowSize = 5;
      int       numSubPartsLeftMode, numSubPartsRightMode, numSubPartsRefMode, leftIntraMode = -1, rightIntraMode = -1;
      int       windowSize = candidate.modeId > DC_IDX ? angWindowSize : 1;
      int       numSamples = cuSize.width << floorLog2(cuSize.height);
      int       numSubPartsLimit = numSamples >= 256 ? maxNumSubPartitions - 1 : 2;

      xFindAlreadyTestedNearbyIntraModes(curIspLfnstIdx, (int)candidate.modeId, &refLfnstIdx, &leftIntraMode, &rightIntraMode, (ISPType)candidate.ispMod, windowSize);

      if (refLfnstIdx != -1 && refLfnstIdx != curIspLfnstIdx)
      {
        CHECK(leftIntraMode != candidate.modeId || rightIntraMode != candidate.modeId, "wrong intra mode and lfnstIdx values!");
        numSubPartsRefMode = m_ispTestedModes[refLfnstIdx].getNumCompletedSubParts((ISPType)candidate.ispMod, candidate.modeId);
        CHECK(numSubPartsRefMode <= 0, "Wrong value of the number of subpartitions completed!");
      }
      else
      {
        numSubPartsLeftMode = leftIntraMode != -1 ? ispTestedModes.getNumCompletedSubParts((ISPType)candidate.ispMod, leftIntraMode) : -1;
        numSubPartsRightMode = rightIntraMode != -1 ? ispTestedModes.getNumCompletedSubParts((ISPType)candidate.ispMod, rightIntraMode) : -1;

        numSubPartsRefMode = std::max(numSubPartsLeftMode, numSubPartsRightMode);
      }

      if (numSubPartsRefMode > 0)
      {
        // The mode was found. Now we check the condition
        testCandidate = numSubPartsRefMode > numSubPartsLimit;
      }
    }

    if (testCandidate)
    {
      modeInfo = candidate;
    }
  }
  else
  {
    //the end of the list was reached, so the split is invalidated
    ispTestedModes.splitIsFinished[nextISPcandSplitType - 1] = true;
  }
}

void IntraSearch::xFindAlreadyTestedNearbyIntraModes(int lfnstIdx, int currentIntraMode, int* refLfnstIdx, int* leftIntraMode, int* rightIntraMode, ISPType ispOption, int windowSize)
{
  bool leftModeFound = false, rightModeFound = false;
  *leftIntraMode = -1;
  *rightIntraMode = -1;
  *refLfnstIdx = -1;
  const unsigned st = ispOption - 1;

  //first we check if the exact intra mode was already tested for another lfnstIdx value
  if (lfnstIdx > 0)
  {
    bool sameIntraModeFound = false;
    if (lfnstIdx == 2 && m_ispTestedModes[1].modeHasBeenTested[currentIntraMode][st])
    {
      sameIntraModeFound = true;
      *refLfnstIdx = 1;
    }
    else if (m_ispTestedModes[0].modeHasBeenTested[currentIntraMode][st])
    {
      sameIntraModeFound = true;
      *refLfnstIdx = 0;
    }

    if (sameIntraModeFound)
    {
      *leftIntraMode = currentIntraMode;
      *rightIntraMode = currentIntraMode;
      return;
    }
  }

  //The mode has not been checked for another lfnstIdx value, so now we look for a similar mode within a window using the same lfnstIdx
  for (int k = 1; k <= windowSize; k++)
  {
    int off = currentIntraMode - 2 - k;
    int leftMode = (off < 0) ? NUM_LUMA_MODE + off : currentIntraMode - k;
    int rightMode = currentIntraMode > DC_IDX ? (((int)currentIntraMode - 2 + k) % 65) + 2 : PLANAR_IDX;

    leftModeFound  = leftMode  != (int)currentIntraMode ? m_ispTestedModes[lfnstIdx].modeHasBeenTested[leftMode][st]  : false;
    rightModeFound = rightMode != (int)currentIntraMode ? m_ispTestedModes[lfnstIdx].modeHasBeenTested[rightMode][st] : false;
    if (leftModeFound || rightModeFound)
    {
      *leftIntraMode = leftModeFound ? leftMode : -1;
      *rightIntraMode = rightModeFound ? rightMode : -1;
      *refLfnstIdx = lfnstIdx;
      break;
    }
  }
}

//It prepares the list of potential intra modes candidates that will be tested using RD costs
bool IntraSearch::xSortISPCandList(double bestCostSoFar, double bestNonISPCost, ModeInfo bestNonISPMode)
{
  int bestISPModeInRelCU = -1;
  m_modeCtrl->setStopNonDCT2Transforms(false);

  if (m_pcEncCfg->getUseFastISP())
  {
    //we check if the ISP tests can be cancelled
    double thSkipISP = 1.4;
    if (bestNonISPCost > bestCostSoFar * thSkipISP)
    {
      for (int splitIdx = 0; splitIdx < NUM_INTRA_SUBPARTITIONS_MODES - 1; splitIdx++)
      {
        for (int j = 0; j < NUM_LFNST_NUM_PER_SET; j++)
        {
          m_ispTestedModes[j].splitIsFinished[splitIdx] = true;
        }
      }
      return false;
    }
    if (!updateISPStatusFromRelCU(bestNonISPCost, bestNonISPMode, bestISPModeInRelCU))
    {
      return false;
    }
  }

  for (int k = 0; k < m_ispCandListHor.size(); k++)
  {
    m_ispCandListHor.at(k).ispMod = HOR_INTRA_SUBPARTITIONS; //we set the correct ISP split type value
  }

  auto origHadList = m_ispCandListHor;   // save the original hadamard list of regular intra
  bool modeIsInList[NUM_LUMA_MODE] = { false };

  m_ispCandListHor.clear();
  m_ispCandListVer.clear();

  // we sort the normal intra modes according to their full RD costs
  std::stable_sort(m_regIntraRDListWithCosts.begin(), m_regIntraRDListWithCosts.end(), ModeInfoWithCost::compareModeInfoWithCost);

  // we get the best angle from the regular intra list
  int bestNormalIntraAngle = -1;
  for (int modeIdx = 0; modeIdx < m_regIntraRDListWithCosts.size(); modeIdx++)
  {
    if (bestNormalIntraAngle == -1 && m_regIntraRDListWithCosts.at(modeIdx).modeId > DC_IDX)
    {
      bestNormalIntraAngle = m_regIntraRDListWithCosts.at(modeIdx).modeId;
      break;
    }
  }

  int mode1 = PLANAR_IDX;
  int mode2 = bestNormalIntraAngle;

  ModeInfo refMode = origHadList.at(0);
  auto* destListPtr = &m_ispCandListHor;
  //List creation

  if (m_pcEncCfg->getUseFastISP() && bestISPModeInRelCU != -1) //RelCU intra mode
  {
    destListPtr->push_back(
      ModeInfo(refMode.mipFlg, refMode.mipTrFlg, refMode.mRefId, refMode.ispMod, bestISPModeInRelCU));
    modeIsInList[bestISPModeInRelCU] = true;
  }
  // Planar
#if JVET_W0103_INTRA_MTS
  // push planar later when FastISP is on.
  if (!m_pcEncCfg->getUseFastISP() && !modeIsInList[mode1])
#else
  if (!modeIsInList[mode1])
#endif
  {
    destListPtr->push_back(ModeInfo(refMode.mipFlg, refMode.mipTrFlg, refMode.mRefId, refMode.ispMod, mode1));
    modeIsInList[mode1] = true;
  }

  // Best angle in regular intra
  if (mode2 != -1 && !modeIsInList[mode2])
  {
    destListPtr->push_back(ModeInfo(refMode.mipFlg, refMode.mipTrFlg, refMode.mRefId, refMode.ispMod, mode2));
    modeIsInList[mode2] = true;
  }
  // Remaining regular intra modes that were full RD tested (except DC, which is added after the angles from regular intra)
  int dcModeIndex = -1;
  for (int remModeIdx = 0; remModeIdx < m_regIntraRDListWithCosts.size(); remModeIdx++)
  {
    int currentMode = m_regIntraRDListWithCosts.at(remModeIdx).modeId;
    if (currentMode != mode1 && currentMode != mode2 && !modeIsInList[currentMode])
    {
      if (currentMode > DC_IDX)
      {
        destListPtr->push_back(ModeInfo(refMode.mipFlg, refMode.mipTrFlg, refMode.mRefId, refMode.ispMod, currentMode));
        modeIsInList[currentMode] = true;
      }
      else if (currentMode == DC_IDX)
      {
        dcModeIndex = remModeIdx;
      }
    }
  }
#if JVET_W0103_INTRA_MTS
  // Planar (after angular modes when FastISP is on)
  if (!modeIsInList[mode1])
  {
    destListPtr->push_back(ModeInfo(refMode.mipFlg, refMode.mipTrFlg, refMode.mRefId, refMode.ispMod, mode1));
    modeIsInList[mode1] = true;
  }
#endif
  // DC is added after the angles from regular intra
  if (dcModeIndex != -1 && !modeIsInList[DC_IDX])
  {
    destListPtr->push_back(ModeInfo(refMode.mipFlg, refMode.mipTrFlg, refMode.mRefId, refMode.ispMod, DC_IDX));
    modeIsInList[DC_IDX] = true;
  }

  // We add extra candidates to the list that will only be tested if ISP is likely to win
  for (int j = 0; j < NUM_LFNST_NUM_PER_SET; j++)
  {
    m_ispTestedModes[j].numOrigModesToTest = (int)destListPtr->size();
#if JVET_W0103_INTRA_MTS
    if (m_pcEncCfg->getUseFastISP() && m_numModesISPRDO != -1 && destListPtr->size() > m_numModesISPRDO)
    {
      m_ispTestedModes[j].numOrigModesToTest = m_numModesISPRDO;
    }
#endif
  }
  const int addedModesFromHadList = 3;
  int       newModesAdded = 0;

  for (int k = 0; k < origHadList.size(); k++)
  {
    if (newModesAdded == addedModesFromHadList)
    {
      break;
    }
    if (
#if ENABLE_DIMD && !JVET_V0087_DIMD_NO_ISP
      origHadList.at(k).modeId == DIMD_IDX ||
#endif
#if JVET_W0123_TIMD_FUSION
      origHadList.at(k).modeId == TIMD_IDX ||
#endif
	!modeIsInList[origHadList.at(k).modeId])
    {
      destListPtr->push_back( ModeInfo( refMode.mipFlg, refMode.mipTrFlg, refMode.mRefId, refMode.ispMod, origHadList.at(k).modeId ) );
      newModesAdded++;
    }
  }

  if (m_pcEncCfg->getUseFastISP() && bestISPModeInRelCU != -1)
  {
    destListPtr->resize(1);
  }

  // Copy modes to other split-type list
  m_ispCandListVer = m_ispCandListHor;
  for (int i = 0; i < m_ispCandListVer.size(); i++)
  {
    m_ispCandListVer[i].ispMod = VER_INTRA_SUBPARTITIONS;
  }

  // Reset the tested modes information to 0
  for (int j = 0; j < NUM_LFNST_NUM_PER_SET; j++)
  {
    for (int i = 0; i < m_ispCandListHor.size(); i++)
    {
      m_ispTestedModes[j].clearISPModeInfo(m_ispCandListHor[i].modeId);
    }
  }
  return true;
}

void IntraSearch::xSortISPCandListLFNST()
{
  //It resorts the list of intra mode candidates for lfnstIdx > 0 by checking the RD costs for lfnstIdx = 0
  ISPTestedModesInfo& ispTestedModesRef = m_ispTestedModes[0];
  for (int splitIdx = 0; splitIdx < NUM_INTRA_SUBPARTITIONS_MODES - 1; splitIdx++)
  {
    ISPType ispMode = splitIdx ? VER_INTRA_SUBPARTITIONS : HOR_INTRA_SUBPARTITIONS;
    if (!m_ispTestedModes[m_curIspLfnstIdx].splitIsFinished[splitIdx] && ispTestedModesRef.testedModes[splitIdx].size() > 1)
    {
      auto& candList   = ispMode == HOR_INTRA_SUBPARTITIONS ? m_ispCandListHor : m_ispCandListVer;
      int bestModeId   = candList[1].modeId > DC_IDX ? candList[1].modeId : -1;
      int bestSubParts = candList[1].modeId > DC_IDX ? ispTestedModesRef.getNumCompletedSubParts(ispMode, bestModeId) : -1;
      double bestCost  = candList[1].modeId > DC_IDX ? ispTestedModesRef.getRDCost(ispMode, bestModeId) : MAX_DOUBLE;
      for (int i = 0; i < candList.size(); i++)
      {
#if ENABLE_DIMD && !JVET_V0087_DIMD_NO_ISP
        if( candList[i].modeId == DIMD_IDX )
        {
          continue;
        }
#endif
#if JVET_W0123_TIMD_FUSION
        if( candList[i].modeId == TIMD_IDX )
        {
          continue;
        }
#endif
        const int candSubParts = ispTestedModesRef.getNumCompletedSubParts(ispMode, candList[i].modeId);
        const double candCost = ispTestedModesRef.getRDCost(ispMode, candList[i].modeId);
        if (candSubParts > bestSubParts || candCost < bestCost)
        {
          bestModeId = candList[i].modeId;
          bestCost = candCost;
          bestSubParts = candSubParts;
        }
      }

      if (bestModeId != -1)
      {
        if (bestModeId != candList[0].modeId)
        {
          auto prevMode = candList[0];
          candList[0].modeId = bestModeId;
          for (int i = 1; i < candList.size(); i++)
          {
            auto nextMode = candList[i];
            candList[i] = prevMode;
            if (nextMode.modeId == bestModeId)
            {
              break;
            }
            prevMode = nextMode;
          }
        }
      }
    }
  }
}

bool IntraSearch::updateISPStatusFromRelCU( double bestNonISPCostCurrCu, ModeInfo bestNonISPModeCurrCu, int& bestISPModeInRelCU )
{
  //It compares the data of a related CU with the current CU to cancel or reduce the ISP tests
  bestISPModeInRelCU = -1;
  if (m_modeCtrl->getRelatedCuIsValid())
  {
    double bestNonISPCostRelCU = m_modeCtrl->getBestDCT2NonISPCostRelCU();
    double costRatio           = bestNonISPCostCurrCu / bestNonISPCostRelCU;
    bool   bestModeRelCuIsMip  = (m_modeCtrl->getIspPredModeValRelCU() >> 5) & 0x1;
    bool   bestModeCurrCuIsMip = bestNonISPModeCurrCu.mipFlg;
    int    relatedCuIntraMode  = m_modeCtrl->getIspPredModeValRelCU() >> 9;
    bool   isSameTypeOfMode    = (bestModeRelCuIsMip && bestModeCurrCuIsMip) || (!bestModeRelCuIsMip && !bestModeCurrCuIsMip);
    bool   bothModesAreAngular = bestNonISPModeCurrCu.modeId > DC_IDX && relatedCuIntraMode > DC_IDX;
    bool   modesAreComparable  = isSameTypeOfMode && (bestModeCurrCuIsMip || bestNonISPModeCurrCu.modeId == relatedCuIntraMode || (bothModesAreAngular && abs(relatedCuIntraMode - (int)bestNonISPModeCurrCu.modeId) <= 5));
    int    status              = m_modeCtrl->getIspPredModeValRelCU();

    if ((status & 0x3) == 0x3) //ISP was not selected in the relCU
    {
      double bestNonDCT2Cost = m_modeCtrl->getBestNonDCT2Cost();
      double ratioWithNonDCT2 = bestNonDCT2Cost / bestNonISPCostRelCU;
      double margin = ratioWithNonDCT2 < 0.95 ? 0.2 : 0.1;

      if (costRatio > 1 - margin && costRatio < 1 + margin && modesAreComparable)
      {
        for (int lfnstVal = 0; lfnstVal < NUM_LFNST_NUM_PER_SET; lfnstVal++)
        {
          m_ispTestedModes[lfnstVal].splitIsFinished[HOR_INTRA_SUBPARTITIONS - 1] = true;
          m_ispTestedModes[lfnstVal].splitIsFinished[VER_INTRA_SUBPARTITIONS - 1] = true;
        }
        return false;
      }
    }
    else if ((status & 0x3) == 0x1) //ISP was selected in the relCU
    {
      double margin = 0.05;

      if (costRatio > 1 - margin && costRatio < 1 + margin && modesAreComparable)
      {
        int  ispSplitIdx = (m_modeCtrl->getIspPredModeValRelCU() >> 2) & 0x1;
        bool lfnstIdxIsNot0 = (bool)((m_modeCtrl->getIspPredModeValRelCU() >> 3) & 0x1);
        bool lfnstIdxIs2 = (bool)((m_modeCtrl->getIspPredModeValRelCU() >> 4) & 0x1);
        int  lfnstIdx = !lfnstIdxIsNot0 ? 0 : lfnstIdxIs2 ? 2 : 1;
        bestISPModeInRelCU = (int)m_modeCtrl->getBestISPIntraModeRelCU();

        for (int splitIdx = 0; splitIdx < NUM_INTRA_SUBPARTITIONS_MODES - 1; splitIdx++)
        {
          for (int lfnstVal = 0; lfnstVal < NUM_LFNST_NUM_PER_SET; lfnstVal++)
          {
            if (lfnstVal == lfnstIdx && splitIdx == ispSplitIdx)
            {
              continue;
            }
            m_ispTestedModes[lfnstVal].splitIsFinished[splitIdx] = true;
          }
        }

        bool stopNonDCT2Transforms = (bool)((m_modeCtrl->getIspPredModeValRelCU() >> 6) & 0x1);
        m_modeCtrl->setStopNonDCT2Transforms(stopNonDCT2Transforms);
      }
    }
    else
    {
      THROW("Wrong ISP relCU status");
    }
  }

  return true;
}

void IntraSearch::xFinishISPModes()
{
  //Continue to the next lfnst index
  m_curIspLfnstIdx++;

  if (m_curIspLfnstIdx < NUM_LFNST_NUM_PER_SET)
  {
    //Check if LFNST is applicable
    if (m_curIspLfnstIdx == 1)
    {
      bool canTestLFNST = false;
      for (int lfnstIdx = 1; lfnstIdx < NUM_LFNST_NUM_PER_SET; lfnstIdx++)
      {
        canTestLFNST |= !m_ispTestedModes[lfnstIdx].splitIsFinished[HOR_INTRA_SUBPARTITIONS - 1] || !m_ispTestedModes[lfnstIdx].splitIsFinished[VER_INTRA_SUBPARTITIONS - 1];
      }
      if (canTestLFNST)
      {
        //Construct the intra modes candidates list for the lfnst > 0 cases
        xSortISPCandListLFNST();
      }
    }
  }
}