getUseAdaptiveQP()函数:在parseConfig()函数中,根据命令读入,由成员变量m_bUseAdaptiveQP保存,默认选项为false
("AdaptiveQP,-aq", m_bUseAdaptiveQP, false, "QP adaptation based on a psycho-visual model")
HEVC编码主要包括两个过程:模式选择和写码流,分别对应compress()和encode()。在模式选择时要统计bit信息,写码流时往bin文件中写入码流。这两种情况下都会调用EncEntropyEncoder这个类,而统计bit和写比特操作,是通过类的多态继承来实现的。
首先是两个主要的类:TEncEntropyIf和TEncEntropy,在TEncEntropy.hpp中定义类
/// entropy encoder pure class
class TEncEntropyIf
{
public:
virtual Void resetEntropy (const TComSlice *pSlice) = 0;
virtual SliceType determineCabacInitIdx (const TComSlice *pSlice) = 0;
virtual Void setBitstream ( TComBitIf* p ) = 0;
virtual Void resetBits () = 0;
virtual UInt getNumberOfWrittenBits() = 0;
virtual Void codeVPS ( const TComVPS* pcVPS ) = 0;
virtual Void codeSPS ( const TComSPS* pcSPS ) = 0;
virtual Void codePPS ( const TComPPS* pcPPS ) = 0;
virtual Void codeSliceHeader ( TComSlice* pcSlice ) = 0;
virtual Void codeTilesWPPEntryPoint ( TComSlice* pSlice ) = 0;
virtual Void codeTerminatingBit ( UInt uilsLast ) = 0;
virtual Void codeSliceFinish () = 0;
virtual Void codeMVPIdx ( TComDataCU* pcCU, UInt uiAbsPartIdx, RefPicList eRefList ) = 0;
public:
virtual Void codeCUTransquantBypassFlag( TComDataCU* pcCU, UInt uiAbsPartIdx ) = 0;
virtual Void codeSkipFlag ( TComDataCU* pcCU, UInt uiAbsPartIdx ) = 0;
virtual Void codeMergeFlag ( TComDataCU* pcCU, UInt uiAbsPartIdx ) = 0;
virtual Void codeMergeIndex ( TComDataCU* pcCU, UInt uiAbsPartIdx ) = 0;
virtual Void codeSplitFlag ( TComDataCU* pcCU, UInt uiAbsPartIdx, UInt uiDepth ) = 0;
virtual Void codePartSize ( TComDataCU* pcCU, UInt uiAbsPartIdx, UInt uiDepth ) = 0;
virtual Void codePredMode ( TComDataCU* pcCU, UInt uiAbsPartIdx ) = 0;
virtual Void codeIPCMInfo ( TComDataCU* pcCU, UInt uiAbsPartIdx ) = 0;
virtual Void codeTransformSubdivFlag( UInt uiSymbol, UInt uiCtx ) = 0;
virtual Void codeQtCbf ( TComTU &rTu, const ComponentID compID, const Bool lowestLevel ) = 0;
virtual Void codeQtRootCbf ( TComDataCU* pcCU, UInt uiAbsPartIdx ) = 0;
virtual Void codeQtCbfZero ( TComTU &rTu, const ChannelType chType ) = 0;
virtual Void codeQtRootCbfZero ( ) = 0;
virtual Void codeIntraDirLumaAng( TComDataCU* pcCU, UInt uiAbsPartIdx, Bool isMultiplePU ) = 0;
virtual Void codeIntraDirChroma( TComDataCU* pcCU, UInt uiAbsPartIdx ) = 0;
virtual Void codeInterDir ( TComDataCU* pcCU, UInt uiAbsPartIdx ) = 0;
virtual Void codeRefFrmIdx ( TComDataCU* pcCU, UInt uiAbsPartIdx, RefPicList eRefList ) = 0;
virtual Void codeMvd ( TComDataCU* pcCU, UInt uiAbsPartIdx, RefPicList eRefList ) = 0;
virtual Void codeCrossComponentPrediction( TComTU &rTu, ComponentID compID ) = 0;
virtual Void codeDeltaQP ( TComDataCU* pcCU, UInt uiAbsPartIdx ) = 0;
virtual Void codeChromaQpAdjustment( TComDataCU* pcCU, UInt uiAbsPartIdx ) = 0;
virtual Void codeCoeffNxN ( TComTU &rTu, TCoeff* pcCoef, const ComponentID compID ) = 0;
virtual Void codeTransformSkipFlags ( TComTU &rTu, ComponentID component ) = 0;
virtual Void codeSAOBlkParam (SAOBlkParam& saoBlkParam, const BitDepths &bitDepths, Bool* sliceEnabled, Bool leftMergeAvail, Bool aboveMergeAvail, Bool onlyEstMergeInfo = false) =0;
virtual Void estBit (estBitsSbacStruct* pcEstBitsSbac, Int width, Int height, ChannelType chType) = 0;
virtual Void codeExplicitRdpcmMode ( TComTU &rTu, const ComponentID compID ) = 0;
virtual ~TEncEntropyIf() {}
};
TEncEntropyIf是一个由纯虚函数定义的抽象类,其成员函数被申明为纯虚函数,具体的函数功能实现留待派生类中定义。
/// entropy encoder class
class TEncEntropy
{
public:
Void setEntropyCoder ( TEncEntropyIf* e );
Void setBitstream ( TComBitIf* p ) { m_pcEntropyCoderIf->setBitstream(p); }
Void resetBits () { m_pcEntropyCoderIf->resetBits(); }
UInt getNumberOfWrittenBits () { return m_pcEntropyCoderIf->getNumberOfWrittenBits(); }
Void resetEntropy (const TComSlice *pSlice) { m_pcEntropyCoderIf->resetEntropy(pSlice); }
SliceType determineCabacInitIdx (const TComSlice *pSlice) { return m_pcEntropyCoderIf->determineCabacInitIdx(pSlice); }
Void encodeSliceHeader ( TComSlice* pcSlice );
Void encodeTilesWPPEntryPoint( TComSlice* pSlice );
Void encodeTerminatingBit ( UInt uiIsLast );
Void encodeSliceFinish ();
TEncEntropyIf* m_pcEntropyCoderIf;
public:
Void encodeVPS ( const TComVPS* pcVPS);
// SPS
Void encodeSPS ( const TComSPS* pcSPS );
Void encodePPS ( const TComPPS* pcPPS );
Void encodeSplitFlag ( TComDataCU* pcCU, UInt uiAbsPartIdx, UInt uiDepth, Bool bRD = false );
Void encodeCUTransquantBypassFlag( TComDataCU* pcCU, UInt uiAbsPartIdx, Bool bRD = false );
Void encodeSkipFlag ( TComDataCU* pcCU, UInt uiAbsPartIdx, Bool bRD = false );
Void encodePUWise ( TComDataCU* pcCU, UInt uiAbsPartIdx );
Void encodeInterDirPU ( TComDataCU* pcSubCU, UInt uiAbsPartIdx );
Void encodeRefFrmIdxPU ( TComDataCU* pcSubCU, UInt uiAbsPartIdx, RefPicList eRefList );
Void encodeMvdPU ( TComDataCU* pcSubCU, UInt uiAbsPartIdx, RefPicList eRefList );
Void encodeMVPIdxPU ( TComDataCU* pcSubCU, UInt uiAbsPartIdx, RefPicList eRefList );
Void encodeMergeFlag ( TComDataCU* pcCU, UInt uiAbsPartIdx );
Void encodeMergeIndex ( TComDataCU* pcCU, UInt uiAbsPartIdx, Bool bRD = false );
Void encodePredMode ( TComDataCU* pcCU, UInt uiAbsPartIdx, Bool bRD = false );
Void encodePartSize ( TComDataCU* pcCU, UInt uiAbsPartIdx, UInt uiDepth, Bool bRD = false );
Void encodeIPCMInfo ( TComDataCU* pcCU, UInt uiAbsPartIdx, Bool bRD = false );
Void encodePredInfo ( TComDataCU* pcCU, UInt uiAbsPartIdx );
Void encodeIntraDirModeLuma ( TComDataCU* pcCU, UInt absPartIdx, Bool isMultiplePU = false );
Void encodeIntraDirModeChroma( TComDataCU* pcCU, UInt uiAbsPartIdx );
Void encodeTransformSubdivFlag( UInt uiSymbol, UInt uiCtx );
Void encodeQtCbf ( TComTU &rTu, const ComponentID compID, const Bool lowestLevel );
Void encodeQtCbfZero ( TComTU &rTu, const ChannelType chType );
Void encodeQtRootCbfZero ( );
Void encodeQtRootCbf ( TComDataCU* pcCU, UInt uiAbsPartIdx );
Void encodeQP ( TComDataCU* pcCU, UInt uiAbsPartIdx, Bool bRD = false );
Void encodeChromaQpAdjustment ( TComDataCU* pcCU, UInt uiAbsPartIdx, Bool bRD = false );
Void encodeCrossComponentPrediction( TComTU &rTu, ComponentID compID );
private:
Void xEncodeTransform ( Bool& bCodeDQP, Bool& codeChromaQpAdj, TComTU &rTu );
public:
Void encodeCoeff ( TComDataCU* pcCU, UInt uiAbsPartIdx, UInt uiDepth, Bool& bCodeDQP, Bool& codeChromaQpAdj );
Void encodeCoeffNxN ( TComTU &rTu, TCoeff* pcCoef, const ComponentID compID );
Void estimateBit ( estBitsSbacStruct* pcEstBitsSbac, Int width, Int height, ChannelType chType );
Void encodeSAOBlkParam(SAOBlkParam& saoBlkParam, const BitDepths &bitDepths, Bool* sliceEnabled, Bool leftMergeAvail, Bool aboveMergeAvail){m_pcEntropyCoderIf->codeSAOBlkParam(saoBlkParam, bitDepths, sliceEnabled, leftMergeAvail, aboveMergeAvail, false);}
static Int countNonZeroCoeffs( TCoeff* pcCoef, UInt uiSize );
};// END CLASS DEFINITION TEncEntropy
TEncEntropy是具体类,也是在代码中经常见到的,常作为GOPEncoder,SliceEncoder等类的成员变量:m_pcEntropyCoder
该类包含唯一的 一个成员变量,指向的抽象类的指针:m_pcEntropyCoderIf
TEncEntropyIf* m_pcEntropyCoderIf;
这个成员变量通过set()函数被赋值
Void TEncEntropy::setEntropyCoder ( TEncEntropyIf* e )
{
m_pcEntropyCoderIf = e;
}
同时TEncEntropy的其他进行encode函数,也都是由m_pcEntropyCoderIf来实现,例如
Void TEncEntropy::encodeSliceHeader ( TComSlice* pcSlice )
{
m_pcEntropyCoderIf->codeSliceHeader( pcSlice );
return;
这样关系一下子就明朗了:首先由派生类的指针或引用作为参数传递给setEntropyCoder函数,这样m_pcEntropyCoderIf成员变代表了不同的派生子类,然后具体的encode任务由不同的派生类来完成,程序对外只有唯一的一个TEncEntropy的函数定义的接口。
那么,继承了TEncEntropyIf的子类有哪些呢?
派生子类TEncCavlc
/// CAVLC encoder class
class TEncCavlc : public SyntaxElementWriter, public TEncEntropyIf
{
public:
TEncCavlc();
virtual ~TEncCavlc();
protected:
Void codeShortTermRefPicSet ( const TComReferencePictureSet* pcRPS, Bool calledFromSliceHeader, Int idx );
Bool findMatchingLTRP ( TComSlice* pcSlice, UInt *ltrpsIndex, Int ltrpPOC, Bool usedFlag );
public:
Void resetEntropy (const TComSlice *pSlice);
SliceType determineCabacInitIdx (const TComSlice* /*pSlice*/) { assert(0); return I_SLICE; };
Void setBitstream ( TComBitIf* p ) { m_pcBitIf = p; }
Void resetBits () { m_pcBitIf->resetBits(); }
UInt getNumberOfWrittenBits() { return m_pcBitIf->getNumberOfWrittenBits(); }
Void codeVPS ( const TComVPS* pcVPS );
Void codeVUI ( const TComVUI *pcVUI, const TComSPS* pcSPS );
Void codeSPS ( const TComSPS* pcSPS );
Void codePPS ( const TComPPS* pcPPS );
Void codeSliceHeader ( TComSlice* pcSlice );
Void codePTL ( const TComPTL* pcPTL, Bool profilePresentFlag, Int maxNumSubLayersMinus1);
Void codeProfileTier ( const ProfileTierLevel* ptl, const Bool bIsSubLayer );
Void codeHrdParameters ( const TComHRD *hrd, Bool commonInfPresentFlag, UInt maxNumSubLayersMinus1 );
Void codeTilesWPPEntryPoint( TComSlice* pSlice );
Void codeTerminatingBit ( UInt uilsLast );
Void codeSliceFinish ();
Void codeMVPIdx ( TComDataCU* pcCU, UInt uiAbsPartIdx, RefPicList eRefList );
Void codeSAOBlkParam(SAOBlkParam& /*saoBlkParam*/, const BitDepths& /*bitDepths*/, Bool* /*sliceEnabled*/, Bool /*leftMergeAvail*/, Bool /*aboveMergeAvail*/, Bool /*onlyEstMergeInfo*/ = false){printf("only supported in CABAC"); assert(0); exit(-1);}
Void codeCUTransquantBypassFlag( TComDataCU* pcCU, UInt uiAbsPartIdx );
Void codeSkipFlag ( TComDataCU* pcCU, UInt uiAbsPartIdx );
Void codeMergeFlag ( TComDataCU* pcCU, UInt uiAbsPartIdx );
Void codeMergeIndex ( TComDataCU* pcCU, UInt uiAbsPartIdx );
Void codeAlfCtrlFlag ( ComponentID /*component*/, UInt /*code*/ ) {printf("Not supported\n"); assert(0);}
Void codeInterModeFlag( TComDataCU* pcCU, UInt uiAbsPartIdx, UInt uiDepth, UInt uiEncMode );
Void codeSplitFlag ( TComDataCU* pcCU, UInt uiAbsPartIdx, UInt uiDepth );
Void codePartSize ( TComDataCU* pcCU, UInt uiAbsPartIdx, UInt uiDepth );
Void codePredMode ( TComDataCU* pcCU, UInt uiAbsPartIdx );
Void codeIPCMInfo ( TComDataCU* pcCU, UInt uiAbsPartIdx );
Void codeTransformSubdivFlag( UInt uiSymbol, UInt uiCtx );
Void codeQtCbf ( TComTU &rTu, const ComponentID compID, const Bool lowestLevel );
Void codeQtRootCbf ( TComDataCU* pcCU, UInt uiAbsPartIdx );
Void codeQtCbfZero ( TComTU &rTu, const ChannelType chType );
Void codeQtRootCbfZero ( );
Void codeIntraDirLumaAng( TComDataCU* pcCU, UInt absPartIdx, Bool isMultiple);
Void codeIntraDirChroma( TComDataCU* pcCU, UInt uiAbsPartIdx );
Void codeInterDir ( TComDataCU* pcCU, UInt uiAbsPartIdx );
Void codeRefFrmIdx ( TComDataCU* pcCU, UInt uiAbsPartIdx, RefPicList eRefList );
Void codeMvd ( TComDataCU* pcCU, UInt uiAbsPartIdx, RefPicList eRefList );
Void codeCrossComponentPrediction( TComTU &rTu, ComponentID compID );
Void codeDeltaQP ( TComDataCU* pcCU, UInt uiAbsPartIdx );
Void codeChromaQpAdjustment( TComDataCU* pcCU, UInt uiAbsPartIdx );
Void codeCoeffNxN ( TComTU &rTu, TCoeff* pcCoef, const ComponentID compID );
Void codeTransformSkipFlags ( TComTU &rTu, ComponentID component );
Void estBit ( estBitsSbacStruct* pcEstBitsSbac, Int width, Int height, ChannelType chType );
Void xCodePredWeightTable ( TComSlice* pcSlice );
Void codeScalingList ( const TComScalingList &scalingList );
Void xCodeScalingList ( const TComScalingList* scalingList, UInt sizeId, UInt listId);
Void codeExplicitRdpcmMode( TComTU &rTu, const ComponentID compID );
};
TEncCavlc是写码流的子类,同时还多继承了父类syntaxElementWritter。TEncCavlc执行code()操作的基本单元,都是调用父类syntaxElementWriter的下面几个函数
#define WRITE_CODE( value, length, name) xWriteCode ( value, length )
#define WRITE_UVLC( value, name) xWriteUvlc ( value )
#define WRITE_SVLC( value, name) xWriteSvlc ( value )
#define WRITE_FLAG( value, name) xWriteFlag ( value )
class SyntaxElementWriter
{
protected:
TComBitIf* m_pcBitIf;
SyntaxElementWriter()
:m_pcBitIf(NULL)
{};
virtual ~SyntaxElementWriter() {};
Void setBitstream ( TComBitIf* p ) { m_pcBitIf = p; }
Void xWriteCode ( UInt uiCode, UInt uiLength );
Void xWriteUvlc ( UInt uiCode );
Void xWriteSvlc ( Int iCode );
Void xWriteFlag ( UInt uiCode );
#if ENC_DEC_TRACE
Void xWriteCodeTr ( UInt value, UInt length, const TChar *pSymbolName);
Void xWriteUvlcTr ( UInt value, const TChar *pSymbolName);
Void xWriteSvlcTr ( Int value, const TChar *pSymbolName);
Void xWriteFlagTr ( UInt value, const TChar *pSymbolName);
#endif
Void xWriteRbspTrailingBits();
UInt xConvertToUInt ( Int iValue ) { return ( iValue <= 0) ? -iValue<<1 : (iValue<<1)-1; }
};
Void SyntaxElementWriter::xWriteCode ( UInt uiCode, UInt uiLength )
{
assert ( uiLength > 0 );
m_pcBitIf->write( uiCode, uiLength );
}