imagecomponent.java

histogram equalization using java

import java.awt.*;
import java.util.LinkedList;
import java.awt.image.BufferedImage;

/**
 * Component to show images
 */
class ImageComponent extends javax.swing.JComponent {
    private LinkedList imageList = new LinkedList();
    private LinkedList rectList = new LinkedList();

    private static final int	PADDING = 5;

    public ImageComponent() {}

    public void addImage(BufferedImage image) {
        if (image == null)
            return;
        
        // add image to list
        imageList.add(image);
        rectList.add(new Rectangle(0, 0, image.getWidth(), image.getHeight()));

        // update scroll bar
        resizeScroller();
    }

    public void clearImages() {
        // clear lists
        imageList.clear();
        rectList.clear();

        // update scroll bar
        resizeScroller();
    }
    
    // assuming we're inside a scrollbar view,
    // resizeScroller updates our preferred size
    // and tells the view to revalidate its bars
    private void resizeScroller() {
        Rectangle	bounds = new Rectangle(0, 0, 0, 0);

        // calculate bounds of images
        for (int i = 0; i < imageList.size(); ++i) {
            Rectangle	rect = (Rectangle)rectList.get(i);
            bounds.height = Math.max(bounds.height, rect.height);
            bounds.width += rect.width;
        }
        bounds.width += PADDING * (imageList.size() + 1);
        bounds.height += 2*PADDING;

        setPreferredSize(bounds.getSize());
        revalidate();
    }

    // paint the images
    public void paint(Graphics g) {
        int offset = PADDING;
        for (int i = 0; i < imageList.size(); ++i) {
            g.drawImage((BufferedImage)imageList.get(i), offset, PADDING, null);
            offset += PADDING + ((Rectangle)rectList.get(i)).width;
        }
    }
}