在compressGOP()函数中
compressGOP(){...for (Int iGOPid=0;iGOPid<m_iGopSize;iGOPid++){m_pcSliceEncoder->initEncSlice ( pcPic, iPOCLast, pocCurr, iGOPid, pcSlice, isField );//设置当前Slice的编码参数，如QP，lambda(基于QP)等if ( m_pcCfg->getUseRateCtrl() ) //若开启码率控制，则会对当前帧进行码率分配，计算RDO的参数lambda和QP{if ( ( pcSlice->getPOC() == 0 && m_pcCfg->getInitialQP() > 0 ) || ( frameLevel == 0 && m_pcCfg->getForceIntraQP() ) ) // QP is specified{}else if ( frameLevel == 0 ) // intra case, but use the model{m_pcSliceEncoder->calCostSliceI(pcPic);//计算intraCost,也就是与complexity相关的参数...m_pcRateCtrl->getRCPic()->getLCUInitTargetBits();//在intra情况下，初始LCU的成员变量m_targetBitsLeftlambda = m_pcRateCtrl->getRCPic()->estimatePicLambda( listPreviousPicture, pcSlice->getSliceType());sliceQP = m_pcRateCtrl->getRCPic()->estimatePicQP( lambda, listPreviousPicture ); }else //normal case{lambda = m_pcRateCtrl->getRCPic()->estimatePicLambda( listPreviousPicture, pcSlice->getSliceType());//计算lambdasliceQP = m_pcRateCtrl->getRCPic()->estimatePicQP( lambda, listPreviousPicture );//QP由lambda计算}}}
对于intra的情况，在compressGOP()中，以CTU为单位，计算了每个CTU的intra cost.
Void TEncSlice::calCostSliceI(TComPic* pcPic) // TODO: this only analyses the first slice segment. What about the others?{Double iSumHadSlice= 0;TComSlice * const pcSlice = pcPic->getSlice(getSliceIdx());const TComSPS &sps= *(pcSlice->getSPS());const Int shift = sps.getBitDepth(CHANNEL_TYPE_LUMA)-8;const Int offset = (shift>0)?(1<<(shift-1)):0;pcSlice->setSliceSegmentBits(0);UInt startCtuTsAddr, boundingCtuTsAddr;xDetermineStartAndBoundingCtuTsAddr ( startCtuTsAddr, boundingCtuTsAddr, pcPic );for( UInt ctuTsAddr = startCtuTsAddr, ctuRsAddr = pcPic->getPicSym()->getCtuTsToRsAddrMap( startCtuTsAddr);ctuTsAddr < boundingCtuTsAddr;ctuRsAddr = pcPic->getPicSym()->getCtuTsToRsAddrMap(++ctuTsAddr) ){// initialize CU encoderTComDataCU* pCtu = pcPic->getCtu( ctuRsAddr );pCtu->initCtu( pcPic, ctuRsAddr );Int height = min( sps.getMaxCUHeight(),sps.getPicHeightInLumaSamples() - ctuRsAddr / pcPic->getFrameWidthInCtus() * sps.getMaxCUHeight() );Int width = min( sps.getMaxCUWidth(), sps.getPicWidthInLumaSamples() - ctuRsAddr % pcPic->getFrameWidthInCtus() * sps.getMaxCUWidth() );Int iSumHad = m_pcCuEncoder->updateCtuDataISlice(pCtu, width, height);//计算CTU的complexity(m_pcRateCtrl->getRCPic()->getLCU(ctuRsAddr)).m_costIntra=(iSumHad+offset)>>shift;iSumHadSlice += (m_pcRateCtrl->getRCPic()->getLCU(ctuRsAddr)).m_costIntra;}m_pcRateCtrl->getRCPic()->setTotalIntraCost(iSumHadSlice);}
updataCtuDataISlice(pCtu,width,height):是8*8的块为单位，取Y分量做Hadam变换，计算每个CTU的累计变换系数之和。TRCLCU有一个数据成员 m_costIntra.
struct TRCLCU{Int m_actualBits;Int m_QP;// QP of skip mode is set to g_RCInvalidQPValueInt m_targetBits;Double m_lambda;Double m_bitWeight;Int m_numberOfPixel;Double m_costIntra;Int m_targetBitsLeft;};
而pic level 的参数alpha和beta以及CTU的参数alpha和beta，都要通过TEncRCSeq来访问：
class TEncRCSeq{Void initPicPara( TRCParameter* picPara = NULL ); // NULL to initial with default valueVoid initLCUPara( TRCParameter** LCUPara = NULL ); // NULL to initial with default value //经过统计规律，给两个参数一个初始值TRCParameter* getPicPara(){ return m_picPara; }TRCParameter getPicPara( Int level ) { assert( level < m_numberOfLevel ); return m_picPara[level]; }Void setPicPara( Int level, TRCParameter para ){ assert( level < m_numberOfLevel ); m_picPara[level] = para; }TRCParameter** getLCUPara(){ return m_LCUPara; }TRCParameter* getLCUPara( Int level ) { assert( level < m_numberOfLevel ); return m_LCUPara[level]; }TRCParameter getLCUPara( Int level, Int LCUIdx ) { assert( LCUIdx < m_numberOfLCU ); return getLCUPara(level)[LCUIdx]; }Void setLCUPara( Int level, Int LCUIdx, TRCParameter para ) { assert( level < m_numberOfLevel ); assert( LCUIdx < m_numberOfLCU ); m_LCUPara[level][LCUIdx] = para; }//对Pic和CTU的alpha和beta参数进行设置、访问//类的数据成员定义private:TRCParameter* m_picPara;//一维数组，每种picture level对应的编码参数值TRCParameter** m_LCUPara;//二维数组，每种picture level下、每个CTUIdx对应的编码参数}
