/**
* author : Segara B. D.
*/
import java.awt.*;
import javax.swing.*;
import java.awt.image.*;
public class ImagePanel extends JComponent
{
private int width, height;
private OFImage panelImage;
public ImagePanel()
{
width = 360;
height = 240;
panelImage = null;
}
public void setImage(OFImage image)
{
if(image != null) {
width = image.getWidth();
height = image.getHeight();
panelImage = image;
repaint();
}
}
public void clearImage()
{
Graphics imageGraphics = panelImage.getGraphics();
imageGraphics.setColor(Color.LIGHT_GRAY);
imageGraphics.fillRect(0, 0, width, height);
repaint();
}
public Dimension getPreferredSize()
{
return new Dimension(width, height);
}
public void paintComponent(Graphics g)
{
Dimension size = getSize();
g.clearRect(0, 0, size.width, size.height);
if(panelImage != null) {
g.drawImage(panelImage, 0, 0, null);
}
}
}
/**
* author : Segara B. D.
*/
import java.awt.*;
import java.awt.image.*;
import javax.swing.*;
public class OFImage extends BufferedImage
{
public OFImage(BufferedImage image)
{
super(image.getColorModel(), image.copyData(null),
image.isAlphaPremultiplied(), null);
}
public OFImage(int width, int height)
{
super(width, height, TYPE_INT_RGB);
}
public void setPixel(int x, int y, Color col)
{
int pixel = col.getRGB();
setRGB(x, y, pixel);
}
public Color getPixel(int x, int y)
{
int pixel = getRGB(x, y);
return new Color(pixel);
}
public void darker()
{
int height = getHeight();
int width = getWidth();
for(int y = 0; y < height; y++) {
for(int x = 0; x < width; x++) {
setPixel(x, y, getPixel(x, y).darker());
}
}
}
public void lighter()
{
int height = getHeight();
int width = getWidth();
for(int y = 0; y < height; y++) {
for(int x = 0; x < width; x++) {
setPixel(x, y, getPixel(x, y).brighter());
}
}
}
public void threshold()
{
int height = getHeight();
int width = getWidth();
for(int y = 0; y < height; y++) {
for(int x = 0; x < width; x++) {
Color pixel = getPixel(x, y);
int brightness = (pixel.getRed() + pixel.getBlue() + pixel.getGreen()) / 3;
if(brightness <= 85) {
setPixel(x, y, Color.BLACK);
}
else if(brightness <= 170) {
setPixel(x, y, Color.GRAY);
}
else {
setPixel(x, y, Color.WHITE);
}
}
}
}
}
/**
* author : Segara B. D.
*/
import java.awt.image.*;
import javax.imageio.*;
import java.io.*;
public class ImageFileManager
{
private static final String IMAGE_FORMAT = "jpg";
public static OFImage loadImage(File imageFile)
{
try {
BufferedImage image = ImageIO.read(imageFile);
if(image == null || (image.getWidth(null) < 0)) {
return null;
}
return new OFImage(image);
}
catch(IOException exc) {
return null;
}
}
public static void saveImage(OFImage image, File file)
{
try {
ImageIO.write(image, IMAGE_FORMAT, file);
}
catch(IOException exc) {
return;
}
}
}
/**
* author : Segara B. D.
*/
import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;
import javax.swing.*;
import java.io.File;
public class ImageViewer
{
private static final String VERSION = "Version 1.0";
private static JFileChooser fileChooser = new JFileChooser(System.getProperty("user.dir"));
private JFrame frame;
private ImagePanel imagePanel;
private JLabel filenameLabel;
private JLabel statusLabel;
private OFImage currentImage;
public ImageViewer()
{
currentImage = null;
makeFrame();
}
private void openFile()
{
int returnVal = fileChooser.showOpenDialog(frame);
if(returnVal != JFileChooser.APPROVE_OPTION) {
return;
}
File selectedFile = fileChooser.getSelectedFile();
currentImage = ImageFileManager.loadImage(selectedFile);
if(currentImage == null) {
JOptionPane.showMessageDialog(frame,
"The file was not in a recognized image file format.",
"Image Load Error",
JOptionPane.ERROR_MESSAGE);
return;
}
imagePanel.setImage(currentImage);
showFilename(selectedFile.getPath());
showStatus("File loaded.");
frame.pack();
}
private void close()
{
currentImage = null;
imagePanel.clearImage();
showFilename(null);
}
private void quit()
{
System.exit(0);
}
private void makeDarker()
{
if(currentImage != null) {
currentImage.darker();
frame.repaint();
showStatus("Applied: darker");
}
else {
showStatus("No image loaded.");
}
}
private void makeLighter()
{
if(currentImage != null) {
currentImage.lighter();
frame.repaint();
showStatus("Applied: lighter");
}
else {
showStatus("No image loaded.");
}
}
private void threshold()
{
if(currentImage != null) {
currentImage.threshold();
frame.repaint();
showStatus("Applied: threshold");
}
else {
showStatus("No image loaded.");
}
}
private void showAbout()
{
JOptionPane.showMessageDialog(frame,
"ImageViewer\n" + VERSION,
"About ImageViewer",
JOptionPane.INFORMATION_MESSAGE);
}
private void showFilename(String filename)
{
if(filename == null) {
filenameLabel.setText("No file displayed.");
}
else {
filenameLabel.setText("File: " + filename);
}
}
private void showStatus(String text)
{
statusLabel.setText(text);
}
private void makeFrame()
{
frame = new JFrame("ImageViewer");
makeMenuBar(frame);
Container contentPane = frame.getContentPane();
contentPane.setLayout(new BorderLayout(6, 6));
filenameLabel = new JLabel();
contentPane.add(filenameLabel, BorderLayout.NORTH);
imagePanel = new ImagePanel();
contentPane.add(imagePanel, BorderLayout.CENTER);
statusLabel = new JLabel(VERSION);
contentPane.add(statusLabel, BorderLayout.SOUTH);
showFilename(null);
frame.pack();
Dimension d = Toolkit.getDefaultToolkit().getScreenSize();
frame.setLocation(d.width/2 - frame.getWidth()/2, d.height/2 - frame.getHeight()/2);
frame.setVisible(true);
}
private void makeMenuBar(JFrame frame)
{
final int SHORTCUT_MASK =
Toolkit.getDefaultToolkit().getMenuShortcutKeyMask();
JMenuBar menubar = new JMenuBar();
frame.setJMenuBar(menubar);
JMenu menu;
JMenuItem item;
menu = new JMenu("File");
menubar.add(menu);
item = new JMenuItem("Open");
item.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_O, SHORTCUT_MASK));
item.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) { openFile(); }
});
menu.add(item);
item = new JMenuItem("Close");
item.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_W, SHORTCUT_MASK));
item.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) { close(); }
});
menu.add(item);
menu.addSeparator();
item = new JMenuItem("Quit");
item.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_Q, SHORTCUT_MASK));
item.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) { quit(); }
});
menu.add(item);
menu = new JMenu("Filter");
menubar.add(menu);
item = new JMenuItem("Darker");
item.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) { makeDarker(); }
});
menu.add(item);
item = new JMenuItem("Lighter");
item.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) { makeLighter(); }
});
menu.add(item);
item = new JMenuItem("Threshold");
item.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) { threshold(); }
});
menu.add(item);
menu = new JMenu("Help");
menubar.add(menu);
item = new JMenuItem("About ImageViewer...");
item.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) { showAbout(); }
});
menu.add(item);
}
}
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