Heph::Fourier Class Reference

class for calculating FFT and Convolution. More...

#include <Fourier.h>

Public Member Functions
	Fourier (const Fourier &)=delete
Fourier &	operator= (const Fourier &)=delete

Static Public Member Functions
static ComplexBuffer	FFT (const DoubleBuffer &doubleBuffer)
static ComplexBuffer	FFT (const DoubleBuffer &doubleBuffer, size_t fftSize)
static void	FFT (ComplexBuffer &complexBuffer)
static void	FFT (ComplexBuffer &complexBuffer, size_t fftSize)
static void	IFFT (DoubleBuffer &doubleBuffer, ComplexBuffer &complexBuffer)
static void	IFFT (ComplexBuffer &complexBuffer, bool scale)
static double	BinFrequencyToIndex (size_t sampleRate, size_t fftSize, double frequency)
static double	IndexToBinFrequency (size_t sampleRate, size_t fftSize, size_t index)
static size_t	CalculateFFTSize (size_t bufferSize)
static DoubleBuffer	Convolve (const DoubleBuffer &source, const DoubleBuffer &kernel)
static DoubleBuffer	Convolve (const DoubleBuffer &source, const DoubleBuffer &kernel, ConvolutionMode convolutionMode)

Detailed Description

class for calculating FFT and Convolution.

Note

this class cannot be instantiated.

Member Function Documentation

FFT() [1/4]

static ComplexBuffer Heph::Fourier::FFT ( const DoubleBuffer & doubleBuffer )

static

computes the forward Fast Fourier Transform.

Parameters

doubleBuffer

real data in time domain.

Returns

complex data in frequency domain.

FFT() [2/4]

static ComplexBuffer Heph::Fourier::FFT ( const DoubleBuffer & doubleBuffer, size_t fftSize )

static

computes the forward Fast Fourier Transform.

Parameters

doubleBuffer	real data in time domain.
fftSize	size of the FFT. Must be a power of 2, if not the closest power of 2 will be used.

Returns

complex data in frequency domain.

FFT() [3/4]

static void Heph::Fourier::FFT ( ComplexBuffer & complexBuffer )

static

computes the forward Fast Fourier Transform.

Parameters

complexBuffer

contains the time domain data in input, and frequency domain data in output.

FFT() [4/4]

static void Heph::Fourier::FFT ( ComplexBuffer & complexBuffer, size_t fftSize )

static

computes the forward Fast Fourier Transform.

Parameters

complexBuffer	contains the time domain data in input, and frequency domain data in output.
fftSize	size of the FFT. Must be a power of 2, if not the closest power of 2 will be used.

IFFT() [1/2]

static void Heph::Fourier::IFFT ( DoubleBuffer & doubleBuffer, ComplexBuffer & complexBuffer )

static

computes the inverse Fast Fourier Transform.

Parameters

doubleBuffer	real data in time domain.
complexBuffer	complex data in frequency domain.

IFFT() [2/2]

static void Heph::Fourier::IFFT ( ComplexBuffer & complexBuffer, bool scale )

static

computes the inverse Fast Fourier Transform.

Parameters

complexBuffer	contains the frequency domain data in input, and time domain data in output.
scale	indicates whether to divide the output by fftSize.

BinFrequencyToIndex()

static double Heph::Fourier::BinFrequencyToIndex ( size_t sampleRate, size_t fftSize, double frequency )

static

computes the corresponding bin index to the provided frequency.

Parameters

sampleRate

the sampling rate of the transformed signal.

IndexToBinFrequency()

static double Heph::Fourier::IndexToBinFrequency ( size_t sampleRate, size_t fftSize, size_t index )

static

computes the corresponding frequency to the provided bin index.

Parameters

sampleRate

the sampling rate of the transformed signal.

CalculateFFTSize()

static size_t Heph::Fourier::CalculateFFTSize ( size_t bufferSize )

static

gets the closest power of 2 that is greater than or equal to the bufferSize.

Convolve() [1/2]

static DoubleBuffer Heph::Fourier::Convolve ( const DoubleBuffer & source, const DoubleBuffer & kernel )

static

computes convolution in Full mode.

Returns

the convolution result.

Convolve() [2/2]

static DoubleBuffer Heph::Fourier::Convolve ( const DoubleBuffer & source, const DoubleBuffer & kernel, ConvolutionMode convolutionMode )

static

computes convolution.

Returns

the convolution result.