fftfilter.h

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#ifndef fftfilter_h
#define fftfilter_h

/*
________________________________________________________________________

(C) dGB Beheer B.V.; (LICENSE) http://opendtect.org/OpendTect_license.txt
Author:        Bruno
Date:          6-10-2009
RCS:           $Id$
________________________________________________________________________

*/


#include "algomod.h"
#include "arrayndalgo.h"
#include "enums.h"
#include "odcomplex.h"

namespace Fourier { class CC; }

template <class T> class Array1DImpl;


mExpClass(Algo) FFTFilter
{

public:
                        FFTFilter(int sz, float step);
                        ~FFTFilter();

                        enum Type               { LowPass, HighPass, BandPass };
                        mDeclareEnumUtils(Type)

    void                setLowPass(float cutf3,float cutf4);
    void                setHighPass(float cutf1,float cutf2);
    void                setBandPass(float cutf1,float cutf2,
                                    float cutf3,float cutf4);
                        // The following will auto taper 5% of the filter size
    void                setLowPass(float cutf4);
    void                setHighPass(float cutf1);
    void                setBandPass(float cutf1,float cutf4);

                        //will taper the array before apply
                        //do not use for strictly positive/negative signal
    bool                setTimeTaperWindow(int sz, BufferString wintype,
                                           float var=0.95);

    bool                apply(Array1DImpl<float>&);
    bool                apply(Array1DImpl<float_complex>&,bool dopreproc=true);

    Array1DImpl<float_complex>* getFreqDomainArr() const
                        { return freqdomain_; }
    void                requestStayInFreqDomain()
                        {stayinfreq_ = true; }

    Type                getFilterType() const;
    bool                isLowPass() const;
    bool                isHighPass() const;


protected:

    int                 fftsz_;
    int                 sz_;
    float               df_;
    float               step_;
    float               cutfreq_[4];

    Fourier::CC*        fft_;
    ArrayNDWindow*      timewindow_;
    ArrayNDWindow*      freqwindow_;
    Array1DImpl<float>* trendreal_;
    Array1DImpl<float>* trendimag_;
    BoolTypeSet         isudfreal_;
    BoolTypeSet         isudfimag_;
    Array1DImpl<float_complex>* freqdomain_;
    bool                        stayinfreq_;

    void                buildFreqTaperWin();

                        // will store the position of undef points
    bool                interpUdf(Array1DImpl<float>&,bool isimag=false);
    bool                interpUdf(Array1DImpl<float_complex>&);
    void                restoreUdf(Array1DImpl<float>&,bool isimag=false) const;
    void                restoreUdf(Array1DImpl<float_complex>&) const;
                        // will store the removed trend
    bool                deTrend(Array1DImpl<float>& outp,bool isimag=false);
    bool                deTrend(Array1DImpl<float_complex>&);
    bool                restoreTrend(Array1DImpl<float>& outp,
                                     bool isimag=false) const;
    bool                restoreTrend(Array1DImpl<float_complex>&) const;
    void                reSize(const Array1DImpl<float_complex>& inp,
                               Array1DImpl<float_complex>& outp) const;
    void                reSize(const Array1DImpl<float>& inp,
                               Array1DImpl<float>& outp) const;
    void                restoreSize(const Array1DImpl<float_complex>& inp,
                                    Array1DImpl<float_complex>& outp) const;
    void                restoreSize(const Array1DImpl<float>& inp,
                                    Array1DImpl<float>& outp) const;
};

#endif