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@heidisu /App.java
Last active May 22, 2017

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Haar transform
package haar;
import javax.imageio.ImageIO;
import javax.swing.*;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.awt.image.FilteredImageSource;
import java.awt.image.ImageFilter;
import java.awt.image.ImageProducer;
import java.io.IOException;
public class App
{
public static void main( String[] args )
{
try {
BufferedImage image = ImageIO.read(App.class.getClassLoader().getResourceAsStream("Lenna.png"));
Image grayScale = convertToGrayScale(image);
BufferedImage bufferedImage = toBufferedImage(grayScale);
displayImage(bufferedImage);
double[][] intmatrix = imageToMatrix(bufferedImage);
double[][] result = haarTransform.transform(intmatrix);
BufferedImage updated = updateImage(bufferedImage, result);
displayImage(updated);
} catch (IOException e) {
e.printStackTrace();
}
}
private static void displayImage(Image image){
JLabel lblimage = new JLabel(new ImageIcon(image));
JFrame frame = new JFrame();
frame.getContentPane().add(lblimage, BorderLayout.CENTER);
frame.setSize(512, 512);
frame.setVisible(true);
JPanel mainPanel = new JPanel(new BorderLayout());
mainPanel.add(lblimage);
frame.add(mainPanel);
frame.setVisible(true);
}
private static Image convertToGrayScale(BufferedImage colorImage){
ImageFilter filter = new GrayFilter(true, 10);
ImageProducer producer = new FilteredImageSource(colorImage.getSource(), filter);
return Toolkit.getDefaultToolkit().createImage(producer);
}
private static BufferedImage toBufferedImage(Image img)
{
if (img instanceof BufferedImage)
{
return (BufferedImage) img;
}
BufferedImage bimage = new BufferedImage(img.getWidth(null), img.getHeight(null), BufferedImage.TYPE_INT_ARGB);
Graphics2D bGr = bimage.createGraphics();
bGr.drawImage(img, 0, 0, null);
bGr.dispose();
return bimage;
}
private static double[][] imageToMatrix(BufferedImage image){
double[][] matrix = new double[image.getWidth()][image.getHeight()];
for(int i = 0; i < image.getWidth(); i++){
for(int j = 0; j < image.getHeight(); j++){
matrix[i][j] = getPixel(image, i, j);
}
}
return matrix;
}
private static int getPixel(BufferedImage image, int x, int y){
int clr = image.getRGB(x, y);
return clr & 0x000000ff;
}
private static BufferedImage updateImage(BufferedImage image, double[][] transform){
for(int i = 0; i< transform.length; i++){
for(int j = 0; j < transform.length; j++){
int value = (int) transform[i][j];
value = value < 0 ? 255 + value : value;
//value = 128 + value;
Color color = new Color(value, value, value);
image.setRGB(i, j, color.getRGB());
}
}
return image;
}
}
package haar;
public class HaarTransform {
public double[][] transform(double[][] input){
return transformRows(transformColumns(input));
}
private double[][] transformColumns(double[][] input){
int size = input.length;
double[][] result = new double[size][size];
for (int j = 0; j < size; j++) {
for (int i = 0; i < size / 2; i++) {
result[i][j] = (input[2*i][j] + input[2*i + 1][j])/2.0;
result[size/2 + i][j] = (input[2*i][j] - input[2*i + 1][j])/2.0;
}
}
return result;
}
private double[][] transformRows(double[][] input){
int size = input.length;
double[][] result = new double[size][size];
for (int i = 0; i < size; i++) {
for (int j = 0; j < size / 2; j++) {
result[i][j] = (input[i][2*j] + input[i][2*j + 1])/2.0;
result[i][size/2 + j] = (input[i][2*j] - input[i][2*j + 1])/2.0;
}
}
return result;
}
}
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