fi.helsinki.cs.ohtu.mpeg2.video
Class RGBToYCbCrConverter

java.lang.Object
  fi.helsinki.cs.ohtu.mpeg2.video.RGBToYCbCrConverter

public class RGBToYCbCrConverter
extends java.lang.Object

A converter from RGB ro YCbCr colour space.

Field Summary

private double[]	coefficients The coefficient table to use for this converter.
static double[]	ITU_R_BT_470_2_COEFFICIENTS If sequence header matrix coefficients value == 5.
static double[]	ITU_R_BT_709_COEFFICIENTS If sequence header matrix coefficients value == 1.

Constructor Summary

RGBToYCbCrConverter()
Initializes with default coefficients.

RGBToYCbCrConverter(double[] c)
Initializes with given coefficients.

Method Summary

int[]	convert(int red, int green, int blue) Converts an RGB value to an YCbCr value.
void	setCoefficients(double[] coefficients) Sets the coefficients.

Methods inherited from class java.lang.Object

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

Field Detail

ITU_R_BT_709_COEFFICIENTS

public static final double[] ITU_R_BT_709_COEFFICIENTS

If sequence header matrix coefficients value == 1. The formula for HDTV colour. Best used when creating content to be viewed with flat-panel televisions.

ITU_R_BT_470_2_COEFFICIENTS

public static final double[] ITU_R_BT_470_2_COEFFICIENTS

If sequence header matrix coefficients value == 5. Analogue television systems. Suits best for content geared towards cathode-ray-tube televisions.

coefficients

private double[] coefficients

The coefficient table to use for this converter. TODO:Describe the format of the table.

Constructor Detail

RGBToYCbCrConverter

public RGBToYCbCrConverter()

Initializes with default coefficients. Initializes RGBToYCbCrConverter object and uses ITU_R_BT_709_COEFFICIENTS as the coefficients for conversion.

RGBToYCbCrConverter

public RGBToYCbCrConverter(double[] c)

Initializes with given coefficients.

Parameters:

c - coefficient table to use for conversion.

Method Detail

setCoefficients

public void setCoefficients(double[] coefficients)

Sets the coefficients.

Parameters:

coefficients - array containing the matrix coefficients used in conversion.

convert

public int[] convert(int red,
                     int green,
                     int blue)

Converts an RGB value to an YCbCr value. Performs the conversion from RGB to YCbCr using the coefficients set for this RGBToYCbCrConverter object.

Parameters:

red - RGB red value (0..255)

green - RGB green value (0..255)

blue - RGB blue value (0..255)

Returns:

{y, cb, cr} as an array.