CASpectralProcessor.h

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#ifndef _SpectralProcesor_H_
#define _SpectralProcesor_H_
 
#if !defined(__COREAUDIO_USE_FLAT_INCLUDES__)
#include <CoreAudio/CoreAudioTypes.h>
#include <CoreFoundation/CoreFoundation.h>
#else
#include <CoreAudioTypes.h>
#include <CoreFoundation.h>
#endif

#include <Accelerate/Accelerate.h>

#include "CAAutoDisposer.h"

struct SpectralBufferList
{
    UInt32 mNumberSpectra;
    DSPSplitComplex mDSPSplitComplex[1];
};

class CASpectralProcessor 
{
public:
    CASpectralProcessor(UInt32 inFFTSize, UInt32 inHopSize, UInt32 inNumChannels, UInt32 inMaxFrames);
    virtual ~CASpectralProcessor();
    
    void Reset();
    
    void Process(UInt32 inNumFrames, AudioBufferList* inInput, AudioBufferList* outOutput);
    
    typedef void (*SpectralFunction)(SpectralBufferList* inSpectra, void* inUserData);
    
    void SetSpectralFunction(SpectralFunction inFunction, void* inUserData);
    
    UInt32 FFTSize() const { return mFFTSize; }
    UInt32 MaxFrames() const { return mMaxFrames; }
    UInt32 NumChannels() const { return mNumChannels; }
    UInt32 HopSize() const { return mHopSize; }
    Float32* Window() const { return mWindow; }
    
    
    void HanningWindow(); // set up a hanning window
    void SineWindow();
    
    void GetFrequencies(Float32* freqs, Float32 sampleRate);                // only for processed forward
    void GetMagnitude(AudioBufferList* inCopy, Float32* min, Float32* max); // only for processed forward
    
    virtual bool ProcessForwards(UInt32 inNumFrames, AudioBufferList* inInput);
    bool ProcessBackwards(UInt32 inNumFrames, AudioBufferList* outOutput);


    void PrintSpectralBufferList();
    
protected:
    void CopyInput(UInt32 inNumFrames, AudioBufferList* inInput);
    void CopyInputToFFT();
    void DoWindowing();
    void DoFwdFFT();
    void DoInvFFT();
    void OverlapAddOutput();
    void CopyOutput(UInt32 inNumFrames, AudioBufferList* inOutput);
    void ProcessSpectrum(UInt32 inFFTSize, SpectralBufferList* inSpectra);
    
    UInt32 mFFTSize;
    UInt32 mHopSize;
    UInt32 mNumChannels;
    UInt32 mMaxFrames;

    UInt32 mLog2FFTSize;
    UInt32 mFFTMask; 
    UInt32 mFFTByteSize;
    UInt32 mIOBufSize;
    UInt32 mIOMask;
    UInt32 mInputSize;
    UInt32 mInputPos;
    UInt32 mOutputPos;
    UInt32 mInFFTPos;
    UInt32 mOutFFTPos;
    FFTSetup mFFTSetup;

    CAAutoFree<Float32> mWindow;
    struct SpectralChannel 
    {
        CAAutoFree<Float32> mInputBuf;      // log2ceil(FFT size + max frames)
        CAAutoFree<Float32> mOutputBuf;     // log2ceil(FFT size + max frames)
        CAAutoFree<Float32> mFFTBuf;        // FFT size
        CAAutoFree<Float32> mSplitFFTBuf;   // FFT size
    };
    CAAutoArrayDelete<SpectralChannel> mChannels;

    CAAutoFree<SpectralBufferList> mSpectralBufferList;
    
    SpectralFunction mSpectralFunction;
    void *mUserData;
    
};


#endif