math.jtransforms.dht
Class DoubleDHT_2D

java.lang.Object
  math.jtransforms.dht.DoubleDHT_2D

public class DoubleDHT_2D
extends java.lang.Object

Computes 2D Discrete Hartley Transform (DHT) of real, double precision data. The sizes of both dimensions can be arbitrary numbers. This is a parallel implementation optimized for SMP systems.

Part of code is derived from General Purpose FFT Package written by Takuya Ooura (http://www.kurims.kyoto-u.ac.jp/~ooura/fft.html)

Author:

Piotr Wendykier (piotr.wendykier@gmail.com)

Constructor Summary

DoubleDHT_2D(int rows, int column)
Creates new instance of DoubleDHT_2D.

Method Summary

void	forward(double[] a) Computes 2D real, forward DHT leaving the result in a.
void	forward(double[][] a) Computes 2D real, forward DHT leaving the result in a.
void	inverse(double[][] a, boolean scale) Computes 2D real, inverse DHT leaving the result in a.
void	inverse(double[] a, boolean scale) Computes 2D real, inverse DHT leaving the result in a.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

DoubleDHT_2D

public DoubleDHT_2D(int rows,
                    int column)

Creates new instance of DoubleDHT_2D.

Parameters:

rows - number of rows

column - number of columns

Method Detail

forward

public void forward(double[] a)

Computes 2D real, forward DHT leaving the result in a. The data is stored in 1D array in row-major order.

Parameters:

a - data to transform

forward

public void forward(double[][] a)

Computes 2D real, forward DHT leaving the result in a. The data is stored in 2D array.

Parameters:

a - data to transform

inverse

public void inverse(double[] a,
                    boolean scale)

Computes 2D real, inverse DHT leaving the result in a. The data is stored in 1D array in row-major order.

Parameters:

a - data to transform

scale - if true then scaling is performed

inverse

public void inverse(double[][] a,
                    boolean scale)

Computes 2D real, inverse DHT leaving the result in a. The data is stored in 2D array.

Parameters:

a - data to transform

scale - if true then scaling is performed