FFT_Wrapper.h

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#ifndef CSL_FFT_WRAPPER_H
#define CSL_FFT_WRAPPER_H

                // I use compiler flags for these, so different apps can share the same code base.
//#define USE_FFTW                          // use FFTW (faster but complicated to build)
//#define USE_FFTREAL                       // use FFTReal (smaller and simpler)
//#define USE_KISSFFT                       // use KISS FFT (smaller and simpler)

#include "CSL_Core.h"

#ifdef USE_FFTW
    #include <fftw3.h>
    #define FFTWrapper FFTW_Wrapper         // which FFT wrapper class to use?
    #define FFTWF_FLAGS FFTW_MEASURE        // or use FFTW_ESTIMATE; FFTW_PRESERVE_INPUT not necessary
#endif

#ifdef USE_FFTREAL
    #include <FFTReal.h>
    #define FFTWrapper FFTR_Wrapper 
#endif

#ifdef USE_KISSFFT
    #include <kiss_fft.h>
    #define FFTWrapper KISSFFT_Wrapper  
#endif

namespace csl {


typedef enum {          
    CSL_FFT_REAL = 0,
    CSL_FFT_COMPLEX,
    CSL_FFT_MAGPHASE
} CSL_FFTType;


typedef enum {          
    CSL_FFT_FORWARD = 0,
    CSL_FFT_INVERSE
} CSL_FFTDir;


class Abst_FFT_W {
public:                         
    Abst_FFT_W(unsigned size, CSL_FFTType type = CSL_FFT_REAL, CSL_FFTDir forward = CSL_FFT_FORWARD) 
                : mSize(size), mCSize((size / 2) + 1), mType(type), mDirection(forward) { };

    ~Abst_FFT_W() { };          

    virtual void nextBuffer(Buffer & in, Buffer & out) throw (CException) = 0;

    unsigned mSize;             
    unsigned mCSize;            
protected:
    CSL_FFTType mType;          
    CSL_FFTDir mDirection;      
};

//
// FFTW-wrapper concrete subclass
//

#ifdef USE_FFTW


class FFTW_Wrapper : public Abst_FFT_W {
public:
    FFTW_Wrapper(unsigned size, CSL_FFTType type = CSL_FFT_REAL, CSL_FFTDir forward = CSL_FFT_FORWARD);
    ~FFTW_Wrapper();
    void nextBuffer(Buffer & in, Buffer & out) throw (CException);

private:        
    SampleBuffer mInBuf;        
    SampleBuffer mSampBuf;      
    fftwf_complex *mSpectBuf;   
    fftwf_plan mPlan;           
};

#endif

//
// FFTReal-wrapper concrete subclass
//

#ifdef USE_FFTREAL


class FFTR_Wrapper : public Abst_FFT_W {
public:
    FFTR_Wrapper(unsigned size, CSL_FFTType type = CSL_FFT_REAL, CSL_FFTDir forward = CSL_FFT_FORWARD);
    ~FFTR_Wrapper();
    void nextBuffer(Buffer & in, Buffer & out) throw (CException);

private:        
    SampleBuffer mTempBuf;      
    FFTReal mFFT;               
};

#endif

//
// KISS_FFT-wrapper concrete subclass (untested)
//

#ifdef USE_KISSFFT


class KISSFFT_Wrapper : public Abst_FFT_W {
public:
    KISSFFT_Wrapper(unsigned size, CSL_FFTType type = CSL_FFT_REAL, CSL_FFTDir forward = CSL_FFT_FORWARD);
    ~KISSFFT_Wrapper();
    void nextBuffer(Buffer & in, Buffer & out) throw (CException);

private:        
    SampleBuffer mTempBuf;      
    kiss_fft_cfg mFFT;          
    SampleComplexVector inBuf, outBuf;
};

#endif

}

#endif