Spectral.h

Go to the documentation of this file.

//
// Spectral.h -- UnitGenerator for going to/from the spectral domain
//  See the copyright notice and acknowledgment of authors in the file COPYRIGHT
//

// 
// These classes require FFTW <http://www.fftw.org> version 3 to work.
//
// As currently stands, the IFFT code expects sample to be float. If sample
// changes to double, this code will have to be revisited.
//
// FFTW Installation:
//   You need to compile FFTW 3.x to handle single-precision floating point numbers.
//   On Unix (incl. Mac OS X) here's what you need to do to compile FFTW in
//   a form compatible with CSL 4:
//     ./configure --enable-float
//     make
//     make install
//
// These all assume that the user is using a BlockResizer if he/she wants different IO block sizes and FFT sizes
// The convolver can only handle monophonic IR files, and reads the whole file into memory for the analysis.

#ifndef CSL_Spectral_H
#define CSL_Spectral_H

#include "CSL_Core.h"
#include "BlockResizer.h"
//#include "Window.h"
#include "sndfile.h"        // Convolver reads a sound file

#include <fftw3.h>

#define FFTW_ENABLE_FLOAT

#ifdef FFTW_ENABLE_FLOAT

#define CSL_FFTW_sample     sample
#define CSL_FFTW_cmplx      fftwf_complex
#define CSL_FFTW_plan       fftwf_plan
#define CSL_FFTW_c2r_plan   fftwf_plan_dft_c2r_1d
#define CSL_FFTW_r2c_plan   fftwf_plan_dft_r2c_1d
#define CSL_FFTW_deplan     fftwf_destroy_plan
#define CSL_FFTW_free       fftwf_free
#define CSL_FFTW_exec       fftwf_execute
#define CSL_FFTW_alloc      fftwf_malloc

#else

#define CSL_FFTW_sample     double
#define CSL_FFTW_plan       fftw_plan
#define CSL_FFTW_cmplx      fftw_complex
#define CSL_FFTW_c2r_plan   fftw_plan_dft_c2r_1d
#define CSL_FFTW_r2c_plan   fftw_plan_dft_r2c_1d
#define CSL_FFTW_deplan     fftw_destroy_plan
#define CSL_FFTW_free       fftw_free
#define CSL_FFTW_exec       fftw_execute
#define CSL_FFTW_alloc      fftw_malloc

#endif

#define CSL_FFTW_MEASURE    FFTW_MEASURE
#define CSL_FFTW_ESTIMATE   FFTW_ESTIMATE

namespace csl {

#ifdef CSL_ENUMS        
typedef enum {          
    CSL_FFT_REAL = 0,
    CSL_FFT_COMPLEX
} CSLFFTType;

typedef enum {
    kFFTMeasure,    
    kFFTEstimate    
} FFTFlags;

#else
    #define CSL_FFT_REAL 0
    #define CSL_FFT_COMPLEX 1
    typedef int CSLFFTType;
    #define kFFTMeasure 0
    #define kFFTEstimate 1
    typedef int  FFTFlags;
#endif


class FFT : public Effect {

public:
    FFT(UnitGenerator & in, CSLFFTType type = CSL_FFT_REAL, FFTFlags flags = kFFTMeasure, int size = CGestalt::blockSize()); 
    ~FFT();
    int fftSize() { return mFFTSize; }

    void nextBuffer(Buffer& outputBuffer) throw (CException);   // we override the general-case version because this needs a mono input

    CSL_FFTW_cmplx *mCmplxSpectrum; 
    CSL_FFTW_sample *mRealSpectrum;     
    bool mOverwriteOutput;              

protected:  
    int mFFTSize;                       
    CSLFFTType mType;                   
    CSL_FFTW_plan mPlan;                
    CSL_FFTW_sample *mSampleBuffer; 
    CSL_FFTW_sample *mInputBuffer;      
//  BlockResizer mBlockResizer;         ///< used to change the size of callbacks to equal the FFT size
    CSL_FFTW_sample *mWindowBuffer; 

    void initialize(FFTFlags flags);    
};

// Inverse FFT

class IFFT : public UnitGenerator {

public:
    IFFT(FFTFlags flags = kFFTMeasure, int size = CGestalt::blockSize()); 
    ~IFFT();
    int fftSize() { return mFFTSize; }
    
    void binValue(int binNumber, float* outRealPart, float* outComplexPart);
    void binValueMagPhase(int binNumber, float* outMag, float* outPhase);   
                            // set the values in the specified bin
    void setBin(int binNumber, float realPart, float complexPart);
    void setBins(float* real, float* complex);
    void setBins(int lower, int upper, float* real, float* complex);
    void setBinMagPhase(int binNumber, float mag, float phase);
    void setBinsMagPhase(float* mags, float* phases);

protected:  
    int mFFTSize;                       
    CSL_FFTW_plan mPlan;                
    CSL_FFTW_cmplx *mSpectrum;          
    CSL_FFTW_cmplx *mTempSpectrum;  
    CSL_FFTW_sample *mSampleBuffer; 
    BlockResizer mBlockResizer;         
    
    void initialize(FFTFlags flags);    
    void nextBuffer(Buffer& outputBuffer, unsigned outBufNum) throw (CException);

};

}

#endif

---