id summary reporter owner description type status priority milestone component version resolution keywords cc 1314 HM Rate Control Bug llzzyynjupt " Based on: jctvc-hm-84d6b158ca1f92cd06840a798b4b11ba22d0586b.zip HM 16.0 Visual C++ 10: In the function ""Void TEncGOP::compressGOP()"", there are codes: if ( m_pcCfg->getUseRateCtrl() ) { Int frameLevel = m_pcRateCtrl->getRCSeq()->getGOPID2Level( iGOPid ); if ( pcPic->getSlice(0)->getSliceType() == I_SLICE ) { frameLevel = 0; } m_pcRateCtrl->initRCPic( frameLevel ); estimatedBits = m_pcRateCtrl->getRCPic()->getTargetBits(); Int sliceQP = m_pcCfg->getInitialQP(); if ( ( pcSlice->getPOC() == 0 && m_pcCfg->getInitialQP() > 0 ) || ( frameLevel == 0 && m_pcCfg->getForceIntraQP() ) ) // QP is specified { Int NumberBFrames = ( m_pcCfg->getGOPSize() - 1 ); Double dLambda_scale = 1.0 - Clip3( 0.0, 0.5, 0.05*(Double)NumberBFrames ); Double dQPFactor = 0.57*dLambda_scale; Int SHIFT_QP = 12; Int bitdepth_luma_qp_scale = 0; Double qp_temp = (Double) sliceQP + bitdepth_luma_qp_scale - SHIFT_QP; lambda = dQPFactor*pow( 2.0, qp_temp/3.0 ); } else if ( frameLevel == 0 ) // intra case, but use the model { '''m_pcSliceEncoder->calCostSliceI(pcPic);''' if ( m_pcCfg->getIntraPeriod() != 1 ) // do not refine allocated bits for all intra case { Int bits = m_pcRateCtrl->getRCSeq()->getLeftAverageBits(); bits = m_pcRateCtrl->getRCPic()->getRefineBitsForIntra( bits ); if ( bits < 200 ) { bits = 200; } m_pcRateCtrl->getRCPic()->setTargetBits( bits ); } list listPreviousPicture = m_pcRateCtrl->getPicList(); m_pcRateCtrl->getRCPic()->getLCUInitTargetBits(); lambda = m_pcRateCtrl->getRCPic()->estimatePicLambda( listPreviousPicture, pcSlice->getSliceType()); sliceQP = m_pcRateCtrl->getRCPic()->estimatePicQP( lambda, listPreviousPicture ); } else // normal case { list listPreviousPicture = m_pcRateCtrl->getPicList(); lambda = m_pcRateCtrl->getRCPic()->estimatePicLambda( listPreviousPicture, pcSlice->getSliceType()); sliceQP = m_pcRateCtrl->getRCPic()->estimatePicQP( lambda, listPreviousPicture ); } sliceQP = Clip3( -pcSlice->getSPS()->getQpBDOffset(CHANNEL_TYPE_LUMA), MAX_QP, sliceQP ); m_pcRateCtrl->getRCPic()->setPicEstQP( sliceQP ); m_pcSliceEncoder->resetQP( pcPic, sliceQP, lambda ); } The line ""m_pcSliceEncoder->calCostSliceI(pcPic);"" can calculate the total intra cost and make the member variable m_pcRateCtrl->m_encRCPic->m_totalCostIntra properly initialized. But when rate control is turned on and the input parameter ""initialQP"" is not set to 0 (e.g. set to 32), the line ""m_pcSliceEncoder->calCostSliceI(pcPic);"" is not executed for the first I Frame. At this time, for the first I frame, the member variable m_pcRateCtrl->m_encRCPic->m_totalCostIntra will not be properly initialized. After encoding the first I frame, the following codes in the function ""Void TEncGOP::compressGOP()"" will be executed: if ( m_pcCfg->getUseRateCtrl() ) { Double avgQP = m_pcRateCtrl->getRCPic()->calAverageQP(); Double avgLambda = m_pcRateCtrl->getRCPic()->calAverageLambda(); if ( avgLambda < 0.0 ) { avgLambda = lambda; } '''m_pcRateCtrl->getRCPic()->updateAfterPicture( actualHeadBits, actualTotalBits, avgQP, avgLambda, pcSlice->getSliceType()); ''' m_pcRateCtrl->getRCPic()->addToPictureLsit( m_pcRateCtrl->getPicList() ); m_pcRateCtrl->getRCSeq()->updateAfterPic( actualTotalBits ); if ( pcSlice->getSliceType() != I_SLICE ) { m_pcRateCtrl->getRCGOP()->updateAfterPicture( actualTotalBits ); } else // for intra picture, the estimated bits are used to update the current status in the GOP { m_pcRateCtrl->getRCGOP()->updateAfterPicture( estimatedBits ); } The function ""m_pcRateCtrl->getRCPic()->updateAfterPicture()"" will call ""updateAlphaBetaIntra(&alpha, &beta);"" in turn. The function ""updateAlphaBetaIntra()"" is defined as: Void TEncRCPic::updateAlphaBetaIntra(Double *alpha, Double *beta) { '''Double lnbpp = log(pow(m_totalCostIntra / (Double)m_numberOfPixel, BETA1));''' Double diffLambda = (*beta)*(log((Double)m_picActualBits)-log((Double)m_targetBits)); diffLambda = Clip3(-0.125, 0.125, 0.25*diffLambda); *alpha = (*alpha) * exp(diffLambda); *beta = (*beta) + diffLambda / lnbpp; } Note that for the first I frame the variable ""m_totalCostIntra"" is not properly initialized. The following configuration file is used: #======== File I/O =============== InputFile : E:\\RaceHorses_832x480.yuv InputBitDepth : 8 # Input bitdepth InputChromaFormat : 420 # Ratio of luminance to chrominance samples FrameRate : 25 # Frame Rate per second FrameSkip : 0 # Number of frames to be skipped in input SourceWidth : 832 # Input frame width SourceHeight : 480 # Input frame height FramesToBeEncoded : 50 # Number of frames to be coded Level : 4.1 #======== File I/O ===================== BitstreamFile : E:\\test.265 ReconFile : E:\\test_rec.yuv #======== Profile ================ Profile : main #======== Unit definition ================ MaxCUWidth : 64 # Maximum coding unit width in pixel MaxCUHeight : 64 # Maximum coding unit height in pixel MaxPartitionDepth : 4 # Maximum coding unit depth QuadtreeTULog2MaxSize : 5 # Log2 of maximum transform size for # quadtree-based TU coding (2...6) QuadtreeTULog2MinSize : 2 # Log2 of minimum transform size for # quadtree-based TU coding (2...6) QuadtreeTUMaxDepthInter : 1 QuadtreeTUMaxDepthIntra : 1 #======== Coding Structure ============= IntraPeriod : 20 # Period of I-Frame ( -1 = only first) DecodingRefreshType : 2 # Random Accesss 0:none, 1:CRA, 2:IDR, 3:Recovery Point SEI GOPSize : 4 # GOP Size (number of B slice = GOPSize-1) # Type POC QPoffset QPfactor tcOffsetDiv2 betaOffsetDiv2 temporal_id #ref_pics_active #ref_pics reference pictures predict deltaRPS #ref_idcs reference idcs Frame1: P 4 1 0.3536 0 0 0 1 1 -4 0 Frame2: B 1 2 0.442 0 0 0 1 2 -1 3 0 Frame3: B 2 3 0.442 0 0 0 1 2 -2 2 0 Frame4: B 3 4 0.442 0 0 0 1 2 -3 1 0 #=========== Motion Search ============= FastSearch : 1 # 0:Full search 1:TZ search SearchRange : 64 # (0: Search range is a Full frame) BipredSearchRange : 4 # Search range for bi-prediction refinement HadamardME : 1 # Use of hadamard measure for fractional ME FEN : 1 # Fast encoder decision FDM : 1 # Fast Decision for Merge RD cost #======== Quantization ============= QP : 32 # Quantization parameter(0-51) MaxDeltaQP : 0 # CU-based multi-QP optimization MaxCuDQPDepth : 0 # Max depth of a minimum CuDQP for sub-LCU-level delta QP DeltaQpRD : 0 # Slice-based multi-QP optimization RDOQ : 1 # RDOQ RDOQTS : 1 # RDOQ for transform skip #=========== Deblock Filter ============ DeblockingFilterControlPresent: 0 # Dbl control params present (0=not present, 1=present) LoopFilterOffsetInPPS : 0 # Dbl params: 0=varying params in SliceHeader, param = base_param + GOP_offset_param; 1=constant params in PPS, param = base_param) LoopFilterDisable : 0 # Disable deblocking filter (0=Filter, 1=No Filter) LoopFilterBetaOffset_div2 : 0 # base_param: -6 ~ 6 LoopFilterTcOffset_div2 : 0 # base_param: -6 ~ 6 DeblockingFilterMetric : 0 # blockiness metric (automatically configures deblocking parameters in bitstream) #=========== Misc. ============ InternalBitDepth : 8 # codec operating bit-depth #=========== Coding Tools ================= SAO : 0 # Sample adaptive offset (0: OFF, 1: ON) AMP : 0 # Asymmetric motion partitions (0: OFF, 1: ON) TransformSkip : 0 # Transform skipping (0: OFF, 1: ON) TransformSkipFast : 1 # Fast Transform skipping (0: OFF, 1: ON) SAOLcuBoundary : 0 # SAOLcuBoundary using non-deblocked pixels (0: OFF, 1: ON) #============ Slices ================ SliceMode : 0 # 0: Disable all slice options. # 1: Enforce maximum number of LCU in an slice, # 2: Enforce maximum number of bytes in an 'slice' # 3: Enforce maximum number of tiles in a slice SliceArgument : 1500 # Argument for 'SliceMode'. # If SliceMode==1 it represents max. SliceGranularity-sized blocks per slice. # If SliceMode==2 it represents max. bytes per slice. # If SliceMode==3 it represents max. tiles per slice. LFCrossSliceBoundaryFlag : 1 # In-loop filtering, including ALF and DB, is across or not across slice boundary. # 0:not across, 1: across #============ PCM ================ PCMEnabledFlag : 0 # 0: No PCM mode PCMLog2MaxSize : 5 # Log2 of maximum PCM block size. PCMLog2MinSize : 3 # Log2 of minimum PCM block size. PCMInputBitDepthFlag : 1 # 0: PCM bit-depth is internal bit-depth. 1: PCM bit-depth is input bit-depth. PCMFilterDisableFlag : 0 # 0: Enable loop filtering on I_PCM samples. 1: Disable loop filtering on I_PCM samples. #============ Tiles ================ TileUniformSpacing : 0 # 0: the column boundaries are indicated by TileColumnWidth array, the row boundaries are indicated by TileRowHeight array # 1: the column and row boundaries are distributed uniformly NumTileColumnsMinus1 : 0 # Number of tile columns in a picture minus 1 TileColumnWidthArray : 2 3 # Array containing tile column width values in units of CTU (from left to right in picture) NumTileRowsMinus1 : 0 # Number of tile rows in a picture minus 1 TileRowHeightArray : 2 # Array containing tile row height values in units of CTU (from top to bottom in picture) LFCrossTileBoundaryFlag : 1 # In-loop filtering is across or not across tile boundary. # 0:not across, 1: across #============ WaveFront ================ WaveFrontSynchro : 0 # 0: No WaveFront synchronisation (WaveFrontSubstreams must be 1 in this case). # >0: WaveFront synchronises with the LCU above and to the right by this many LCUs. #=========== Quantization Matrix ================= ScalingList : 0 # ScalingList 0 : off, 1 : default, 2 : file read ScalingListFile : scaling_list.txt # Scaling List file name. If file is not exist, use Default Matrix. #============ Lossless ================ TransquantBypassEnableFlag : 0 # Value of PPS flag. CUTransquantBypassFlagForce: 0 # Force transquant bypass mode, when transquant_bypass_enable_flag is enabled #============ Rate Control ====================== RateControl : 1 # Rate control: enable rate control TargetBitrate : 1000000 # Rate control: target bitrate, in bps KeepHierarchicalBit : 0 # Rate control: 0: equal bit allocation; 1: fixed ratio bit allocation; 2: adaptive ratio bit allocation LCULevelRateControl : 0 # Rate control: 1: LCU level RC; 0: picture level RC RCLCUSeparateModel : 0 # Rate control: use LCU level separate R-lambda model InitialQP : 32 # Rate control: initial QP RCForceIntraQP : 0 # Rate control: force intra QP to be equal to initial QP ### DO NOT ADD ANYTHING BELOW THIS LINE ### ### DO NOT DELETE THE EMPTY LINE BELOW ### " defect new major HM HM-14.0 fbossen ksuehring davidf jct-vc@…