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Preston_5564C06.fm Page 186 Friday, September 23, 2005 5:13 AM

186 CHAPTER 6 ■ VISION

} catch (Exception e) {
e.printStackTrace();
System.exit(0);
}
}
}

Code Objective
The code objective here is to convert an image from an RGB image to a greyscale image.

Code Discussion
The class containing all the image processing methods is called ImageProcessor. I’ve created a
factory method in this class called process(), which takes a FilterParameter called parms, and
then depending on its value, it calls the individual processing method. This is very similar to
the Java Advanced Imaging ParameterBlock and JAI.create() methods. See Example 6-11.

Example 6-11. ImageProcessor.java
package com.scottpreston.javarobot.chapter6;

import java.awt.Color;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.RenderingHints;
import java.awt.Toolkit;
import java.awt.geom.AffineTransform;
import java.awt.image.BufferedImage;
import java.awt.image.renderable.ParameterBlock;

import javax.media.jai.Histogram;
import javax.media.jai.JAI;
import javax.media.jai.KernelJAI;
import javax.media.jai.PlanarImage;

public class ImageProcessor {

private BufferedImage lastImage;

public static final String FILTER_RGB_TO_GREY = "1";
public static final String FILTER_MOTION = "2";
public static final String FILTER_COLOR = "3";
public static final String FILTER_THRESHHOLD = "4";
public static final String FILTER_THRESHHOLD_COLOR = "5";
public static final String FILTER_COLOR_RATIO = "6";
public static final String FILTER_EDGE = "7";