DCT Class Reference

#include <DCT.h>

Public Member Functions
	DCT (int n)
	Construct a DCT object to calculate the Discrete Cosine Transform given input of size n samples. More...
	~DCT ()
void	forward (const double *in, double *out)
	Carry out a type-II DCT of size n, where n is the value provided to the constructor above. More...
void	forwardUnitary (const double *in, double *out)
	Carry out a type-II unitary DCT of size n, where n is the value provided to the constructor above. More...
void	inverse (const double *in, double *out)
	Carry out a type-III (inverse) DCT of size n, where n is the value provided to the constructor above. More...
void	inverseUnitary (const double *in, double *out)
	Carry out a type-III (inverse) unitary DCT of size n, where n is the value provided to the constructor above. More...

Private Attributes
int	m_n
double	m_scale
std::vector< double >	m_scaled
std::vector< double >	m_time2
std::vector< double >	m_freq2r
std::vector< double >	m_freq2i
FFTReal	m_fft

Detailed Description

Definition at line 23 of file DCT.h.

Constructor & Destructor Documentation

DCT::DCT

(

int

n

)

Construct a DCT object to calculate the Discrete Cosine Transform given input of size n samples.

The transform is implemented using an FFT of size 4n, for simplicity.

Definition at line 20 of file DCT.cpp.

References m_n, and m_scale.

DCT::~DCT

(

)

Definition at line 31 of file DCT.cpp.

Member Function Documentation

void DCT::forward	(	const double *	in,
		double *	out
	)

Carry out a type-II DCT of size n, where n is the value provided to the constructor above.

The in and out pointers must point to (enough space for) n values.

Definition at line 36 of file DCT.cpp.

References FFTReal::forward(), m_fft, m_freq2i, m_freq2r, m_n, and m_time2.

Referenced by forwardUnitary().

void DCT::forwardUnitary	(	const double *	in,
		double *	out
	)

Carry out a type-II unitary DCT of size n, where n is the value provided to the constructor above.

This is a scaled version of the type-II DCT corresponding to a transform with an orthogonal matrix. This is the transform implemented by the dct() function in MATLAB.

The in and out pointers must point to (enough space for) n values.

Definition at line 51 of file DCT.cpp.

References forward(), m_n, and m_scale.

void DCT::inverse	(	const double *	in,
		double *	out
	)

Carry out a type-III (inverse) DCT of size n, where n is the value provided to the constructor above.

The in and out pointers must point to (enough space for) n values.

Definition at line 61 of file DCT.cpp.

References FFTReal::inverse(), m_fft, m_freq2i, m_freq2r, m_n, and m_time2.

Referenced by inverseUnitary().

void DCT::inverseUnitary	(	const double *	in,
		double *	out
	)

Carry out a type-III (inverse) unitary DCT of size n, where n is the value provided to the constructor above.

This is the inverse of forwardUnitary().

The in and out pointers must point to (enough space for) n values.

Definition at line 83 of file DCT.cpp.

References inverse(), m_n, m_scale, and m_scaled.

Member Data Documentation

int DCT::m_n

private

Definition at line 76 of file DCT.h.

Referenced by DCT(), forward(), forwardUnitary(), inverse(), and inverseUnitary().

double DCT::m_scale

private

Definition at line 77 of file DCT.h.

Referenced by DCT(), forwardUnitary(), and inverseUnitary().

std::vector<double> DCT::m_scaled

private

Definition at line 78 of file DCT.h.

Referenced by inverseUnitary().

std::vector<double> DCT::m_time2

private

Definition at line 79 of file DCT.h.

Referenced by forward(), and inverse().

std::vector<double> DCT::m_freq2r

private

Definition at line 80 of file DCT.h.

Referenced by forward(), and inverse().

std::vector<double> DCT::m_freq2i

private

Definition at line 81 of file DCT.h.

Referenced by forward(), and inverse().

FFTReal DCT::m_fft

private

Definition at line 82 of file DCT.h.

Referenced by forward(), and inverse().

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

• DCT.h
• DCT.cpp