Simac::ConstantQTransform Class Reference

ConstantQTransform extract a ConstantQ spectrum using Blankertz's paper algorithm. More...

#include <ConstantQTransform.hxx>

List of all members.

Public Types
typedef std::vector< double >	ConstantQSpectrum
typedef std::vector< double >	Spectrum
Public Member Functions
void	doIt (const std::vector< double > &fftData)
	ConstantQTransform (unsigned FS, double fmin, double fmax, unsigned binsPerOctave)
void	sparsekernel (double)
	~ConstantQTransform ()
const ConstantQSpectrum &	constantQSpectrum () const
double	getQ () const
int	getK () const
int	getfftlength () const

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Detailed Description

ConstantQTransform extract a ConstantQ spectrum using Blankertz's paper algorithm.

This transformation is similar to the Fourier transform but it generates bins which bins are proportional to their center frequency.

This implementation saves computational time by moving most computation to configuration time and using a fft as starting point for the transform.

Parameters:

• samplinRate: The sampling rate for the input audio
• minFrequency: The minimum frequency to be considered
• maxFrequency: The maximum frequency to be considered
• binsPerOctave: The number of bins required for each octave

Configuration Outputs:

• Q: Quality factor for the bins
• K: Number of Constant Q spectrum bins
• spectrumSize: Number of required fft spectrum bins

Inputs:

• spectrum: An interlaced complex spectrum (complex, so, size 2*fftLength)

Outputs:

• constantQSpectrum: An interlaced complex spectrum (complex, so, size 2*K)

Definition at line 57 of file ConstantQTransform.hxx.

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Member Typedef Documentation

typedef std::vector<double> Simac::ConstantQTransform::ConstantQSpectrum

Definition at line 60 of file ConstantQTransform.hxx.

typedef std::vector<double> Simac::ConstantQTransform::Spectrum

Definition at line 61 of file ConstantQTransform.hxx.

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Constructor & Destructor Documentation

Simac::ConstantQTransform::ConstantQTransform	(	unsigned	FS,
		double	fmin,
		double	fmax,
		unsigned	binsPerOctave
	)

Definition at line 42 of file ConstantQTransform.cxx.

References Simac::nextpow2().

Simac::ConstantQTransform::~ConstantQTransform

(

)

Definition at line 59 of file ConstantQTransform.cxx.

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Member Function Documentation

const ConstantQSpectrum& Simac::ConstantQTransform::constantQSpectrum

(

)

const [inline]

Definition at line 87 of file ConstantQTransform.hxx.

Referenced by doIt().

void Simac::ConstantQTransform::doIt

(

const std::vector< double > &

fftData

)

Definition at line 116 of file ConstantQTransform.cxx.

References constantQSpectrum().

int Simac::ConstantQTransform::getfftlength

(

)

const [inline]

Definition at line 90 of file ConstantQTransform.hxx.

int Simac::ConstantQTransform::getK

(

)

const [inline]

Definition at line 89 of file ConstantQTransform.hxx.

double Simac::ConstantQTransform::getQ

(

)

const [inline]

Definition at line 88 of file ConstantQTransform.hxx.

void Simac::ConstantQTransform::sparsekernel

(

double

thresh

)

Definition at line 63 of file ConstantQTransform.cxx.

References FourierTransform::doIt(), FourierTransform::spectrum(), and Simac::squaredModule().

Referenced by Simac::ChordExtractor::~ChordExtractor().

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The documentation for this class was generated from the following files:

• ConstantQTransform.hxx
• ConstantQTransform.cxx