biasgain.cpp

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// $Id: biasgain.cpp 1282 2006-06-09 09:46:49Z alex $
//------------------------------------------------
//  CProfileBiasGain.cpp
//------------------------------------------------
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 */




#include "camtypes.h"

//#include "biasgain.h" - in camtypes.h [AUTOMATICALLY REMOVED]
#include "clamp.h"









const AFp  CProfileBiasGain::kSmallAmount_s( 0.00001 );










CProfileBiasGain::CProfileBiasGain ()
    : IProfile()/*,
      BiasMinus1ToPlus1_m( AFp(0.0) ),
      GainMinus1ToPlus1_m( AFp(0.0) ),
      Bias_m( AFp(0.0) ),
      Gain_m( AFp(0.0) ),
      DomainLow_m   ( AFp(0.0) ),
      DomainLength_m( AFp(1.0) ),
      RangeLow_m    ( AFp(0.0) ),
      RangeLength_m ( AFp(1.0) )*/
{

    CProfileBiasGain::SetBiasGain( AFp(0.0),  AFp(0.0) );
    CProfileBiasGain::SetDefaultIntervals();
    generatesInfiniteUndo = FALSE;
}



CProfileBiasGain::CProfileBiasGain ( AFp BiasMinus1ToPlus1,  AFp GainMinus1ToPlus1 )
    : IProfile()/*,
      BiasMinus1ToPlus1_m( AFp(0.0) ),
      GainMinus1ToPlus1_m( AFp(0.0) ),
      Bias_m( AFp(0.0) ),
      Gain_m( AFp(0.0) ),
      DomainLow_m   ( AFp(0.0) ),
      DomainLength_m( AFp(1.0) ),
      RangeLow_m    ( AFp(0.0) ),
      RangeLength_m ( AFp(1.0) )*/
{

    CProfileBiasGain::SetBiasGain( BiasMinus1ToPlus1,  GainMinus1ToPlus1 );
    CProfileBiasGain::SetDefaultIntervals();
    generatesInfiniteUndo = FALSE;
}




CProfileBiasGain::~CProfileBiasGain ()
{
}




CProfileBiasGain::CProfileBiasGain ( const CProfileBiasGain& Other )
    /*: IProfile( Other ),
      BiasMinus1ToPlus1_m( Other.BiasMinus1ToPlus1_m ),
      GainMinus1ToPlus1_m( Other.GainMinus1ToPlus1_m ),
      Bias_m( Other.Bias_m ),
      Gain_m( Other.Gain_m ),
      DomainLow_m   ( Other.DomainLow_m ),
      DomainLength_m( Other.DomainLength_m ),
      RangeLow_m    ( Other.RangeLow_m ),
      RangeLength_m ( Other.RangeLength_m )*/
{

    CProfileBiasGain::operator=( Other );

}




CProfileBiasGain&  CProfileBiasGain::operator= ( const CProfileBiasGain& Other )
{

    IProfile::operator=( Other );

    BiasMinus1ToPlus1_m  =  Other.BiasMinus1ToPlus1_m;
    GainMinus1ToPlus1_m  =  Other.GainMinus1ToPlus1_m;
    Bias_m               =  Other.Bias_m;
    Gain_m               =  Other.Gain_m;

    DomainLow_m     =  Other.DomainLow_m;
    DomainLength_m  =  Other.DomainLength_m;
    RangeLow_m      =  Other.RangeLow_m;
    RangeLength_m   =  Other.RangeLength_m;

    return  *this;

}











void  CProfileBiasGain::SetBiasGain ( AFp BiasMinus1ToPlus1,  AFp GainMinus1ToPlus1 )
{

    SetBias( BiasMinus1ToPlus1 );
    SetGain( GainMinus1ToPlus1 );

}



void  CProfileBiasGain::SetBias ( AFp BiasMinus1ToPlus1 )
{

    BiasMinus1ToPlus1  =  ClampBetween( BiasMinus1ToPlus1,  AFp(-1.0),  AFp(+1.0) );


    const AFp  BiasZeroToOne( ConvertIntervalMinus1Plus1ToZeroOne( BiasMinus1ToPlus1 ) );


    BiasMinus1ToPlus1_m  =  BiasMinus1ToPlus1;
    Bias_m               =  BiasZeroToOne;

}



void  CProfileBiasGain::SetGain ( AFp GainMinus1ToPlus1 )
{

    GainMinus1ToPlus1  =  ClampBetween( GainMinus1ToPlus1,  AFp(-1.0),  AFp(+1.0) );


    const AFp  GainZeroToOne( ConvertIntervalMinus1Plus1ToZeroOne( GainMinus1ToPlus1 ) );


    GainMinus1ToPlus1_m  =  GainMinus1ToPlus1;
    Gain_m               =  GainZeroToOne;

}


AFp  CProfileBiasGain::GetBias ()   const
{

    return  BiasMinus1ToPlus1_m;

}


AFp  CProfileBiasGain::GetGain ()   const
{

    return  GainMinus1ToPlus1_m;

}






AFp  CProfileBiasGain::MapZeroToOne ( AFp InputZeroToOne )   const
{

    InputZeroToOne  =  ClampBetween( InputZeroToOne,  AFp(0.0),  AFp(1.0) );


    AFp  BiasedGained( 0.0 );
    {
        if(     ( BiasMinus1ToPlus1_m  !=  AFp(0.0) )
            ||  ( GainMinus1ToPlus1_m  !=  AFp(0.0) ) )
        {
            BiasedGained  =  BiasGain( Bias_m,  Gain_m,  InputZeroToOne );
        }
        else
        {
            BiasedGained  =  InputZeroToOne; 
        }
    }


    return  BiasedGained;

}






void  CProfileBiasGain::SetIntervals ( AFp Low,   AFp High )
{

    SetIntervals( Low, High,  Low, High );

}



void  CProfileBiasGain::SetIntervals ( AFp DomainLow,  AFp DomainHigh,  AFp RangeLow,  AFp RangeHigh )
{

    AFp  DomainLength( DomainHigh - DomainLow );
    AFp  RangeLength(  RangeHigh  - RangeLow  );


    if( DomainLength == AFp(0.0) )
    {
        DomainLength  =  kSmallAmount_s;
    }
    if( RangeLength  == AFp(0.0) )
    {
        RangeLength   =  kSmallAmount_s;
    }


    DomainLow_m     =  DomainLow;
    DomainLength_m  =  DomainLength;

    RangeLow_m      =  RangeLow;
    RangeLength_m   =  RangeLength;

}



AFp  CProfileBiasGain::MapInterval ( AFp InputDomain )   const
{

    InputDomain  =  ClampBetween( InputDomain,  DomainLow_m,  DomainLow_m + DomainLength_m );


    const AFp  InputZeroToOne( ScaleDomainToZeroOne( InputDomain ) );

    const AFp  BiasedGained( MapZeroToOne( InputZeroToOne ) );

    const AFp  OutputRange( ScaleZeroOneToRange( BiasedGained ) );


    return  OutputRange;

}



void  CProfileBiasGain::MapInterval ( AFp Table[],  INT32 TableLength )   const
{

    if( Table != 0 )
    {

        const AFp  Increment( AFp(1.0) / AFp(TableLength) );
              AFp  InputZeroOne( 0.0 );


        for( INT32 Index = 0  ;  Index < TableLength  ;  ++Index  )
        {
            const AFp  BiasedGained( MapZeroToOne( InputZeroOne ) );
            const AFp  OutputRange( ScaleZeroOneToRange( BiasedGained ) );

            Table[ Index ]  =  OutputRange;
            
            InputZeroOne   +=  Increment;
        }

    }

}





bool  CProfileBiasGain::operator== ( const CProfileBiasGain& Other )   const
{

    const bool  IsSame  =      ( Bias_m  ==  Other.Bias_m )
                           &&  ( Gain_m  ==  Other.Gain_m );

    return  IsSame;

}











AFp  CProfileBiasGain::ConvertIntervalMinus1Plus1ToZeroOne ( AFp Minus1ToPlus1 )   
{

    //static const AFp  kShrink( ( AFp(1.0) - kSmallAmount_s ) / AFp(2.0) );   /// (0,1]
    static const AFp  kShrink( ( AFp(1.0) / AFp(2.0) ) - kSmallAmount_s );     

    const AFp  ZeroToOne( ( Minus1ToPlus1 + AFp(1.0) ) * kShrink + kSmallAmount_s );


    return  ZeroToOne;

}


AFp  CProfileBiasGain::ScaleDomainToZeroOne ( AFp InDomain )   const
{

    if( DomainLength_m  !=  AFp(0.0) )
    {
        return  ( InDomain - DomainLow_m ) / DomainLength_m;
    }
    else
    {
        return  AFp( 0.0 );
    }

}

    
AFp  CProfileBiasGain::ScaleZeroOneToRange ( AFp InZeroOne )   const
{

    return   ( InZeroOne * RangeLength_m ) + RangeLow_m;

}

    
    
    






AFp  CProfileBiasGain::BiasGain ( AFp bias,  AFp gain,  AFp Input )   
{

    const AFp  Biased( Bias( bias,  Input  ) );
    const AFp  Output( Gain( gain,  Biased ) );

    return  Output;

}



AFp  CProfileBiasGain::Bias ( AFp Bias,  AFp Input )   
{

    static const AFp  kOne( 1.0 );
    static const AFp  kTwo( 2.0 );

//  const AFp  Output( Input  /  ( ( kOne / Bias - kTwo ) * ( kOne - Input ) + kOne ) );
    const AFp  Output( Input*Bias  /  ( ( kOne - kTwo*Bias ) * ( kOne - Input ) + Bias ) );


    return  Output;

}



AFp  CProfileBiasGain::Gain ( AFp Gain,   AFp Input )   
{

    static const AFp  kOne( 1.0 );
    static const AFp  kTwo( 2.0 );
    static const AFp  kHalf( 0.5 );

//  const AFp  CommonPart( ( kOne / Gain - kTwo ) * ( kOne - kTwo * Input ) );
    const AFp  CommonPart( ( kOne - kTwo*Gain ) * ( kOne - kTwo * Input ) );

    if( Input  <  kHalf )
    {
//      return  Input / ( CommonPart + kOne );
        return  Input*Gain / ( CommonPart + Gain );
    }
    else
    {
//      return  ( CommonPart - Input ) / ( CommonPart - kOne );
        return  ( CommonPart - Input*Gain ) / ( CommonPart - Gain );
    }

}





void  CProfileBiasGain::SetDefaultIntervals ()
{

    DomainLow_m     =  AFp( 0.0 );
    DomainLength_m  =  AFp( 1.0 );
    RangeLow_m      =  AFp( 0.0 );
    RangeLength_m   =  AFp( 1.0 );

}

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