wt.csm.html.query
Class DCT

java.lang.Object
  wt.csm.html.query.DCT

class DCT

extends Object

Field Summary

Object[]	Divisors
double[]	DivisorsChrominance
double[]	DivisorsLuminance
int	N DCT Block Size - default 8
int	QUALITY Image Quality (0-100) - default 80 (good image / good compression)
Object[]	quantum
int[]	quantum_chrominance Quantitization Matrix for chrominance.
int[]	quantum_luminance Quantitization Matrix for luminace.

Constructor Summary

DCT(int QUALITY)
Constructs a new DCT object.

Method Summary

double[][]	forwardDCT(float[][] input)
double[][]	forwardDCTExtreme(float[][] input)
private void	initMatrix(int quality)
int[]	quantizeBlock(double[][] inputData, int code)
int[]	quantizeBlockExtreme(double[][] inputData, int code)

Methods inherited from class java.lang.Object

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

Field Detail

N

public int N

DCT Block Size - default 8

QUALITY

public int QUALITY

Image Quality (0-100) - default 80 (good image / good compression)

quantum

public Object[] quantum

Divisors

public Object[] Divisors

quantum_luminance

public int[] quantum_luminance

Quantitization Matrix for luminace.

DivisorsLuminance

public double[] DivisorsLuminance

quantum_chrominance

public int[] quantum_chrominance

Quantitization Matrix for chrominance.

DivisorsChrominance

public double[] DivisorsChrominance

Constructor Detail

DCT

public DCT(int QUALITY)

Constructs a new DCT object. Initializes the cosine transform matrix these are used when computing the DCT and it's inverse. This also initializes the run length counters and the ZigZag sequence. Note that the image quality can be worse than 25 however the image will be extemely pixelated, usually to a block size of N.

Parameters:

QUALITY - The quality of the image (0 worst - 100 best)

Method Detail

initMatrix

private void initMatrix(int quality)

forwardDCTExtreme

public double[][] forwardDCTExtreme(float[][] input)

forwardDCT

public double[][] forwardDCT(float[][] input)

quantizeBlock

public int[] quantizeBlock(double[][] inputData,
                           int code)

quantizeBlockExtreme

public int[] quantizeBlockExtreme(double[][] inputData,
                                  int code)