DCT Class Reference

Algorithm to perform a Discrete Cosine Transform of a vector of Real values. More...

#include <DCT.h>

List of all members.

Public Types
enum	DCTType {   I = 0, II = 1, III = 2, IV = 3,   OCTAVE = 4 }
	Specifies the type of the DCT. More...
Public Member Functions
	DCT (int inputSize=1024, int dctSize=1024, bool scale=false, DCTType dctType=OCTAVE)
	~DCT ()
void	process (const MatrixXR &frames, MatrixXR *dct)
DCTType	dctType () const
void	setDctType (DCTType type, bool callSetup=true)
int	inputSize () const
void	setInputSize (int size, bool callSetup=true)
int	dctSize () const
void	setDctSize (int size, bool callSetup=true)

---

Detailed Description

Algorithm to perform a Discrete Cosine Transform of a vector of Real values.

This class represents an object to perform Discrete Cosine Transform (DCT) on Real data. The algorithm takes as input N-point vectors of Real values and returns M-point vectors of Real values.

5 types of DCT are implemented:

1. Type I
2. Type II
3. Type III
4. Type IV
5. Octave's Implementation

The DCT type can be selected using the setDCTType() taking as argument a DCTType.

Author:

Ricard Marxer

See also:

FFT

---

Member Enumeration Documentation

enum DCTType

Specifies the type of the DCT.

See also:

dctType

Enumerator:

I	DCT Type-I
II	DCT Type-II
III	DCT Type-III
IV	DCT Type-IV
OCTAVE	Octave's implementation

---

Constructor & Destructor Documentation

DCT	(	int	inputSize = 1024,
		int	dctSize = 1024,
		bool	scale = false,
		DCTType	dctType = OCTAVE
	)

Constructs a DCT object with the given inputSize, dctSize, scale, dctType parameters.

References setDctSize(), setDctType(), and setInputSize().

~DCT

(

)

Destroys the algorithm and frees its resources.

---

Member Function Documentation

void process	(	const MatrixXR &	frames,
		MatrixXR *	dct
	)

Performs a Discrete Cosine Transform on each of the rows of frames and puts the resulting DCT in the rows of dct.

Parameters:

	frames	matrix of Real values. The number of columns of frames must be equal to the inputSize.
	dct	pointer to a matrix of Real values for the output. The matrix should have the same number of rows as frames and dctSize columns.

Note that if the output matrix is not of the required size it will be resized, reallocating a new memory space if necessary.

Referenced by MFCC::process().

DCT::DCTType dctType

(

)

const

Returns the type of the DCT

By default it is OCTAVE.

void setDctType	(	DCTType	type,
		bool	callSetup = true
	)

Specifies the type of the DCT

Referenced by DCT().

int inputSize

(

)

const

Returns the size of the input arrays. The default is 1024.

See also:

setInputSize()

void setInputSize	(	int	size,
		bool	callSetup = true
	)

Specifies the size of the input. The given size must be higher than 0. Note that if size is a power of 2 the algorithm will perform faster.

See also:

inputSize()

Referenced by DCT().

int dctSize

(

)

const

Returns the output size of the DCT

Note that the result will when performing the DCT at the most inputSize coefficients will be outputed.

By default it is 1024.

void setDctSize	(	int	size,
		bool	callSetup = true
	)

Specifies the output size of the DCT

Note that the result will when performing the DCT at the most inputSize coefficients will be outputed.

By default it is 1024.

Referenced by DCT().

---

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

• DCT.h
• DCT.cpp