[hardwired]

Code:

import java.awt.*;
import java.awt.image.*;
import java.io.*;
import javax.imageio.ImageIO;
import javax.swing.*;
import static java.lang.Thread.*;


public class TestAlpha extends JFrame
{
    private TestAlpha()
    {
        setBounds (0,0,300,325);
        setDefaultCloseOperation(EXIT_ON_CLOSE);
        Container c = getContentPane();
        Image3screen thescreen = new Image3screen();
        c.setLayout(new BorderLayout());
        c.add(thescreen, BorderLayout.CENTER);
    }

    public static void main (String[] args)
    {
        TestAlpha img1 = new TestAlpha();
        img1.setVisible(true);
    }
}

class Image3screen extends JPanel implements Runnable
{
    private Image source, result;
    private int alphaLevel = 0;
    int alphaInc = 10;
    private AlphaFilter af;
    Thread thread;
    boolean filtering = false;
    
    public Image3screen()
    {
        try
        {
            source = ImageIO.read(new File(//"rico.jpg"));
                                           "taiChi.jpg"));
        }
        catch(IOException e)
        {
             System.out.println("read error: " + e.getMessage());
        }
        result = source;
//        repaint();  nothing showing yet/nothing to paint
        alphaLevel = alphaInc;
        start();
    }

    private void start()
    {
        if(!filtering)
        {
            filtering = true;
            thread = new Thread(this);
            thread.setPriority(NORM_PRIORITY);
            thread.start();
        }
    }

    public void run()
    {
        while(filtering)
        {
            try
            {
                sleep(200);
            }
            catch (InterruptedException ex)
            {
                System.out.println("interrupted");
                filtering = false;
            }

            alphaLevel += alphaInc;
            if(alphaLevel < 10 || alphaLevel > 90)
                alphaInc *= -1;

            //System.out.println("alphaLevel = " + alphaLevel);
            filterImage();
        }
    } 

    private void filterImage() 
    { 
        result = createImage(new FilteredImageSource(source.getSource(),
                     new AlphaFilter(alphaLevel)));
        repaint();
    }

    public void paintComponent(Graphics g) 
    {
        super.paintComponent(g);
        g.drawImage(result,0,0,this);
    } 
}

class AlphaFilter extends RGBImageFilter 
{
    private int alphaLevel;

    public AlphaFilter(int alpha) 
    {
        alphaLevel = alpha;
        canFilterIndexColorModel = true;
    }

    public int filterRGB(int x, int y, int rgb) 
    {
        int alpha = (rgb >> 24) & 0xff;
        alpha = (alpha * alphaLevel) / 255;

        return ((rgb & 0x00ffffff) | (alpha << 24));
    } 
}