net.sourceforge.openstego.util.dwt

Class DWT

java.lang.Object

net.sourceforge.openstego.util.dwt.DWT

public class DWT
extends java.lang.Object

Class to handle Discrete Wavelet Transforms (DWT). This class is conversion of C to Java for the file "dwt.c" file provided by Peter Meerwald at: http://www.cosy.sbg.ac.at/~pmeerw/Watermarking/ Refer to his thesis on watermarking: Peter Meerwald, Digital Image Watermarking in the Wavelet Transfer Domain, Master's Thesis, Department of Scientific Computing, University of Salzburg, Austria, January 2001.

Constructor Summary

Constructors

Constructor and Description
DWT(int cols, int rows, int filterID, int level, int method) Default constructor

Method Summary

Modifier and Type	Method and Description
ImageTree	forwardDWT(int[][] pixels) Method to perform forward DWT on the pixel data
ImageTree	forwardDWTwp(int[][] pixels) Method to perform forward DWT (WP) on the pixel data
void	inverseDWT(ImageTree dwts, int[][] pixels) Method to perform inverse DWT to get back the pixel data

Methods inherited from class java.lang.Object

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

Constructor Detail

DWT

public DWT(int cols,
           int rows,
           int filterID,
           int level,
           int method)

Default constructor

Parameters:

cols - Image width

rows - Image height

filterID - Filter ID to use

level - Decomposition level

method - Wavelet filtering method

Method Detail

forwardDWT

public ImageTree forwardDWT(int[][] pixels)

Method to perform forward DWT on the pixel data

Parameters:

pixels - Image pixel data

Returns:

Image tree data after DWT

forwardDWTwp

public ImageTree forwardDWTwp(int[][] pixels)

Method to perform forward DWT (WP) on the pixel data

Parameters:

pixels - Image pixel data

Returns:

Image tree data after DWT

inverseDWT

public void inverseDWT(ImageTree dwts,
                       int[][] pixels)

Method to perform inverse DWT to get back the pixel data

Parameters:

dwts - DWT data as image tree

pixels - Image pixel data