GrabandFadewithRasters.java Source code

Introduction

Here is the source code for GrabandFadewithRasters.java

Source

/*
    
Java Media APIs: Cross-Platform Imaging, Media and Visualization
Alejandro Terrazas
Sams, Published November 2002, 
ISBN 0672320940
*/

import java.applet.Applet;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.image.DataBuffer;
import java.awt.image.DataBufferInt;
import java.awt.image.MemoryImageSource;
import java.awt.image.PixelGrabber;
import java.awt.image.Raster;
import java.awt.image.SampleModel;
import java.awt.image.SinglePixelPackedSampleModel;
import java.awt.image.WritableRaster;
import java.net.MalformedURLException;
import java.net.URL;

import javax.swing.JFrame;

/**
 * GrabandFadewithRasters.java -- displays provided image and then slowly fades
 * to black
 */
public class GrabandFadewithRasters extends Applet {
    private Image originalImage;

    private Image newImage;

    private MemoryImageSource mis;

    private int width;

    private int height;

    private int index = 10;

    private int[] originalPixelArray;

    private boolean imageLoaded = false;

    private WritableRaster raster;

    private String imageURLString = "file:images/peppers.png";

    public void init() {
        URL url;
        try {
            url = new URL(imageURLString);
            originalImage = getImage(url);
        } catch (MalformedURLException me) {
            showStatus("Malformed URL: " + me.getMessage());
        }

        try {
            PixelGrabber grabber = new PixelGrabber(originalImage, 0, 0, -1, -1, true);
            if (grabber.grabPixels()) {
                width = grabber.getWidth();
                height = grabber.getHeight();
                originalPixelArray = (int[]) grabber.getPixels();

                mis = new MemoryImageSource(width, height, originalPixelArray, 0, width);
                mis.setAnimated(true);
                newImage = createImage(mis);
            } else {
                System.err.println("Grabbing Failed");
            }
        } catch (InterruptedException ie) {
            System.err.println("Pixel Grabbing Interrupted");
        }

        DataBufferInt dbi = new DataBufferInt(originalPixelArray, width * height);

        int bandmasks[] = { 0xff000000, 0x00ff0000, 0x0000ff00, 0x000000ff };
        SampleModel sm;
        sm = new SinglePixelPackedSampleModel(DataBuffer.TYPE_INT, width, height, bandmasks);

        raster = Raster.createWritableRaster(sm, dbi, null);
    }

    public void update(Graphics g) {
        paint(g);
    }

    public void paint(Graphics g) {
        int value;
        int sourceRed, sourceGreen, sourceBlue;
        if (newImage != null) {
            g.drawImage(newImage, 0, 0, this);
            if (imageLoaded == false) {
                imageLoaded = true;
                for (int x = 0; x < width; x += 1)
                    for (int y = 0; y < height; y += 1) {
                        value = originalPixelArray[x * height + y];
                        sourceRed = raster.getSample(x, y, 1);
                        sourceGreen = raster.getSample(x, y, 2);
                        sourceBlue = raster.getSample(x, y, 3);

                        if (sourceRed > index) {
                            sourceRed -= index;
                            imageLoaded = false;
                        } else
                            sourceRed = 0;

                        if (sourceGreen > index) {
                            sourceGreen -= index;
                            imageLoaded = false;
                        } else
                            sourceGreen = 0;

                        if (sourceBlue > index) {
                            sourceBlue -= index;
                            imageLoaded = false;
                        } else
                            sourceBlue = 0;

                        raster.setSample(x, y, 1, sourceRed);
                        raster.setSample(x, y, 2, sourceGreen);
                        raster.setSample(x, y, 3, sourceBlue);
                    }
                mis.newPixels();
            }
        }
    }

    public static void main(String[] argv) {
        JFrame frame = new JFrame();
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        GrabandFadewithRasters a = new GrabandFadewithRasters();

        frame.getContentPane().add(a);
        frame.setSize(300, 300);
        a.init();
        a.start();
        frame.setVisible(true);

    }
}