//传入的tempLUT和bestLUT表示编码当前块之前所维护的HMVP列表信息
void EncCu::xCompressCU( CodingStructure*& tempCS, CodingStructure*& bestCS, Partitioner& partitioner, double maxCostAllowed )
{CHECK(maxCostAllowed < 0, "Wrong value of maxCostAllowed!");uint32_t compBegin;uint32_t numComp;bool jointPLT = false;//调色板模式if (partitioner.isSepTree( *tempCS )){if( !CS::isDualITree(*tempCS) && partitioner.treeType != TREE_D ){compBegin = COMPONENT_Y;//从亮度分量（Y分量）开始处理numComp = (tempCS->area.chromaFormat != CHROMA_400)?3: 1;//需要处理的颜色分量数量jointPLT = true;}else{if (isLuma(partitioner.chType)){compBegin = COMPONENT_Y;numComp   = 1;}else{compBegin = COMPONENT_Cb;numComp   = 2;}}}else{compBegin = COMPONENT_Y;numComp = (tempCS->area.chromaFormat != CHROMA_400) ? 3 : 1;jointPLT = true;}SplitSeries splitmode = -1;uint8_t   bestLastPLTSize[MAX_NUM_CHANNEL_TYPE];Pel       bestLastPLT[MAX_NUM_COMPONENT][MAXPLTPREDSIZE]; // store LastPLT foruint8_t   curLastPLTSize[MAX_NUM_CHANNEL_TYPE];Pel       curLastPLT[MAX_NUM_COMPONENT][MAXPLTPREDSIZE]; // store LastPLT if no partitionfor (int i = compBegin; i < (compBegin + numComp); i++){ComponentID comID = jointPLT ? (ComponentID)compBegin : ((i > 0) ? COMPONENT_Cb : COMPONENT_Y);bestLastPLTSize[comID] = 0;curLastPLTSize[comID] = tempCS->prevPLT.curPLTSize[comID];memcpy(curLastPLT[i], tempCS->prevPLT.curPLT[i], tempCS->prevPLT.curPLTSize[comID] * sizeof(Pel));}Slice&   slice      = *tempCS->slice;const PPS &pps      = *tempCS->pps;//图像参数集const SPS &sps      = *tempCS->sps;//序列参数集const uint32_t uiLPelX  = tempCS->area.Y().lumaPos().x;const uint32_t uiTPelY  = tempCS->area.Y().lumaPos().y;const ModeType modeTypeParent  = partitioner.modeType;const TreeType treeTypeParent  = partitioner.treeType;const ChannelType chTypeParent = partitioner.chType;const UnitArea currCsArea = clipArea( CS::getArea( *bestCS, bestCS->area, partitioner.chType ), *tempCS->picture );m_modeCtrl->initCULevel( partitioner, *tempCS );//该函数对m_modeCtrl进行初始化，对需要test的各种模式进行压栈等操作
#if GDR_ENABLED//渐进式解码器刷新if (m_pcEncCfg->getGdrEnabled()){bool isInGdrInterval = slice.getPicHeader()->getInGdrInterval();// 1.0 applicable to inter picture onlyif (isInGdrInterval){int gdrPocStart = m_pcEncCfg->getGdrPocStart();int gdrInterval = m_pcEncCfg->getGdrInterval();int picWidth = slice.getPPS()->getPicWidthInLumaSamples();int m1, m2, n1;int curPoc = slice.getPOC();int gdrPoc = (curPoc - gdrPocStart) % gdrInterval;int begGdrX = 0;int endGdrX = 0;double dd = (picWidth / (double)gdrInterval);int mm = (int)((picWidth / (double)gdrInterval) + 0.49999);m1 = ((mm + 7) >> 3) << 3;m2 = ((mm + 0) >> 3) << 3;if (dd > mm && m1 == m2){m1 = m1 + 8;}n1 = (picWidth - m2 * gdrInterval) / 8;if (gdrPoc < n1){begGdrX = m1 * gdrPoc;endGdrX = begGdrX + m1;}else{begGdrX = m1 * n1 + m2 * (gdrPoc - n1);endGdrX = begGdrX + m2;if (picWidth <= endGdrX){begGdrX = picWidth;endGdrX = picWidth;}}bool isInRefreshArea = tempCS->withinRefresh(begGdrX, endGdrX);if (isInRefreshArea){m_modeCtrl->forceIntraMode();}else if (tempCS->containRefresh(begGdrX, endGdrX) || tempCS->overlapRefresh(begGdrX, endGdrX)){// 1.3.1 enable only vertical splits (QT, BT_V, TT_V)m_modeCtrl->forceVerSplitOnly();// 1.3.2 remove TT_V if it does not satisfy the conditionif (tempCS->refreshCrossTTV(begGdrX, endGdrX)){m_modeCtrl->forceRemoveTTV();}}if (tempCS->area.lwidth() != tempCS->area.lheight()){m_modeCtrl->forceRemoveQT();}if (!m_modeCtrl->anyPredModeLeft()){m_modeCtrl->forceRemoveDontSplit();}if (isInRefreshArea && !m_modeCtrl->anyIntraIBCMode() && (tempCS->area.lwidth() == 4 || tempCS->area.lheight() == 4)){m_modeCtrl->finishCULevel(partitioner);return;}}}
#endif//(CU) 进行压缩之前进行一些初始化和预处理工作if( partitioner.currQtDepth == 0 && partitioner.currMtDepth == 0 &