AmbisonicUtilities.h

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/*

HOA_Utilities.h -- Higher Order Ambisonic utility classes
See the copyright notice and acknowledgment of authors in the file COPYRIGHT
Higher Order Ambisonic classes written by Jorge Castellanos, Graham Wakefield, Florian Hollerweger, 2005

Utility classes used by HOA_Encoder, MOA_Encoder, AmbisonicRotator, MOA_Rotator, HOA_Decoder

*/

#ifndef AMBISONIC_UTILITIES_H
#define AMBISONIC_UTILITIES_H

#include "CSL_Core.h"
#include "Ambisonic.h"

#define AMBI_INVSQRT2 (1/1.414213562)

namespace csl {


void singularValueDecomposition(sample** a, int m, int n, sample* w, sample** v);

void fumaEncodingWeights(sample *weights, const AmbisonicOrder &order, sample azimuth, sample elevation);

void fumaIndexedEncodingWeights(sample *weights, const AmbisonicOrder &order, sample &azimuth, sample &elevation);


class AmbisonicMixer : public AmbisonicUnitGenerator {
public:
    
    // Constructors & destructor:
    AmbisonicMixer(unsigned order = 1); // Default constructor
    AmbisonicMixer(unsigned hOrder, unsigned vOrder); // Default constructor
    
//  AmbisonicMixer(UnitGenerator &input);
    
    ~AmbisonicMixer();  

    void initialize();
    
    void addInput(AmbisonicUnitGenerator &input);
    void addInput(UnitGenerator &input);
        
    unsigned numInputs() { return mInputs.size(); };    

    // nextBuffer(). Does the DSP processing for the Ambisonic Mixer.
    virtual void nextBuffer(Buffer &outputBuffer, unsigned outBufNum) throw(CException);

protected:

    vector<UnitGenerator *> mInputs;        
    Buffer *mInBuffer;                      // buffer for the input framestream

    float mInvNumInputs;                   // the inverse of the number of inputs (used for normalization)
    
};

typedef enum {
    kTILT = 0, 
    kTUMBLE, 
    kROTATE // to be used with the "setNthInput" method to add control sources
} Axes;                                     // tilt -> x axis, tumble -> y axis, rotate -> z axis

class AmbisonicRotator : public AmbisonicUnitGenerator {
public:
    
    // Constructors & destructor:
        
    AmbisonicRotator(AmbisonicUnitGenerator &input);
    
    AmbisonicRotator(UnitGenerator &input, unsigned order);
    
    AmbisonicRotator(UnitGenerator &input, unsigned vorder, unsigned horder);

    ~AmbisonicRotator(); // destructor
    
    
    // set control input sources according axis flag
    void setNthInput(float amount, Axes axis);
    void setTilt(float amount);
    void setTumble(float amount);
    void setRotate(float amount);
    
    // Overriding Framestream::next_buffer(). Does the DSP processing for the Ambisonic Rotator.
    virtual void nextBuffer(Buffer &outputBuffer, unsigned outBufNum) throw(CException);
                
protected:
    unsigned mNumFrames;
    unsigned mGreaterOrder;
    unsigned mNumChannelsGreaterOrder;
    unsigned *mChannelIndex;        // index to the output buffer in the encoding functions.
    unsigned *mInputChannelIndex;   // index to the input buffer in the encoding functions (in case input order != output order)
    bool mShouldRotate, mShouldTurn, mShouldTilt;   // flags to note whether rotation in each axis is being used

private:
    UGenPort *mInputPort;

    sample mRotate, mTumble, mTilt;             // the current amount of rotation in each axis (in radians)
    sample *mSinAngle, *mCosAngle;              // Used to hold sines/cosines of tilt, tumble, rotate angles during audio processing
    sample **mOutPtr, **mInPtr;                 // pointers to Ambisonic encoded input and Ambisonic encoded & rotated output buffers
    
    void initialize(UnitGenerator &input);  
    
    // methods for tilt, tumble & rotate at each order
    void tiltFirstOrder();
    void tiltSecondOrder();
    void tiltThirdOrder();
    
    void tumbleFirstOrder();
    void tumbleSecondOrder();
    void tumbleThirdOrder();
    
    // methods for rotation at each order
    // separated by horizontal & vertical for hybrid order systems (which can be rotated, but not tilted or tumbled)
    void rotateZerothOrder();
    void rotateFirstOrderHorizontal();  
    void rotateSecondOrderHorizontal();
    void rotateThirdOrderHorizontal();
    void rotateFirstOrderVertical();    
    void rotateSecondOrderVertical();
    void rotateThirdOrderVertical();

    
};


}

#endif

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