Tugas 8a PBO: ImageViewer 1.0

Class ImageViewer:

 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) {  // image file was not a valid image  
       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);  
   }  
 }  

Class ImageFileManager

 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;  
     }  
   }  
 }  

Class ImagePanel

 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);  
     }  
   }  
 }  

Class OFImage

 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);  
         }  
       }  
     }  
   }  
 }  

Output: