teaching machines

CS 245 Lecture 6 – Manipulating Images and Custom Painting

February 6, 2014 by Chris Johnson. Filed under cs245, lectures, spring 2014.

Agenda

• what ?s
• manipulating images
• custom drawing
• supporting mouse interaction

TODO

• The preassignment is due before Monday. The homework in this class is challenging. On top of that, Eclipse will kick you in the shin, the EGit plugin will pee on you, and Bitbucket will smash your laptop against the concrete. Don’t expect crunch-time miracles. That stuff doesn’t happen when you’re learning something. If you are far from the finish line, aim for the lesser line—the later-week submission line. Create all your classes and methods according to the PDF. Make sure stuff compiles, but methods may otherwise be blank. Then submit. Do this when your instructional staff is around to support you.
• Also, be aware that we run MOSS on all submissions to compare your code to every other students.

Code

PhotoBop.java

package lecture06;

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.image.BufferedImage;
import java.beans.DesignMode;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;

public class PhotoBop extends JFrame {
  private BufferedImage sourceImage;
  private JLabel sourceLabel;
  private JLabel destinationLabel;
  
  public PhotoBop(String path) throws IOException {
    super("PhotoBop");
    
    sourceImage = ImageIO.read(new File(path));
    
    JButton flipButton = new JButton("Flip");
    JButton uglifyButton = new JButton("Uglify");
    
    add(flipButton, BorderLayout.NORTH);
    add(uglifyButton, BorderLayout.SOUTH);
    
    sourceLabel = new JLabel(new ImageIcon(sourceImage));
    destinationLabel = new JLabel();
    
    add(sourceLabel, BorderLayout.WEST);
    add(destinationLabel, BorderLayout.EAST);
    
    flipButton.addActionListener(new ActionListener() {
      @Override
      public void actionPerformed(ActionEvent arg0) {
        // INSTEAD OF FILLING THIS CODE UP WITH ALL THE IMAGE
        // MANIPULATION MUMBO JUMBO, I'M GOING TO DEFER
        flip();
      }
    });
    
    uglifyButton.addActionListener(new ActionListener() {
      @Override
      public void actionPerformed(ActionEvent e) {
        uglify();
      }
    });
    
    setSize(1024, 768);
    setDefaultCloseOperation(EXIT_ON_CLOSE);
    setVisible(true);
  }
  
  private void flip() {
    BufferedImage destinationImage =
        new BufferedImage(sourceImage.getWidth(),
                          sourceImage.getHeight(),
                          sourceImage.getType());
    for (int c = 0; c < destinationImage.getWidth(); ++c) {
      for (int r = 0; r < destinationImage.getHeight(); ++r) {
        int sourceColorAsInt = sourceImage.getRGB(sourceImage.getWidth() - 1 - c, r);
        destinationImage.setRGB(c, r, sourceColorAsInt);
      }
    }
    
    destinationLabel.setIcon(new ImageIcon(destinationImage));
  }
  
  private void uglify() {
    BufferedImage destinationImage =
        new BufferedImage(sourceImage.getWidth(),
                          sourceImage.getHeight(),
                          sourceImage.getType());
    
    for (int c = 0; c < destinationImage.getWidth(); ++c) {
      for (int r = 0; r < destinationImage.getHeight(); ++r) {
        int sourceColorAsInt = sourceImage.getRGB(c, r);
        Color color = new Color(sourceColorAsInt);
//        color = color.darker();
//        color = color.darker();
//        color = color.darker();
        Color swappedColor = new Color(color.getGreen(), color.getBlue(), color.getRed());
        destinationImage.setRGB(c, r, swappedColor.getRGB());
      }
    }
    
    destinationLabel.setIcon(new ImageIcon(destinationImage));
  }
  
  public static void main(String[] args) throws IOException {
//    JFrame frame = new JFrame("PhotoBop");
    
    new PhotoBop("/Users/johnch/Desktop/nye.jpg");
  }
}

PolylineArtist.java

package lecture06;

import java.awt.BorderLayout;
import java.awt.Graphics;
import java.awt.Point;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.util.ArrayList;
import javax.swing.JFrame;
import javax.swing.JPanel;

public class PolylineArtist extends JFrame implements MouseListener{
  private DrawingPanel panel;
  private ArrayList<Point> clicks;
  
  public PolylineArtist() {
    panel = new DrawingPanel();
    add(panel, BorderLayout.CENTER);
    
    clicks = new ArrayList<Point>();
    addMouseListener(this);
    
    setSize(1024, 768);
    setDefaultCloseOperation(EXIT_ON_CLOSE);
    setVisible(true);
  }
  
  class DrawingPanel extends JPanel {
    public void paintComponent(Graphics g) {
//      g.drawOval(10, 10, 100, 30);
      for (Point p : clicks) {
        g.drawOval(p.x, p.y, 10, 10);
      }
    }
  }
  
  public static void main(String[] args) {
    new PolylineArtist();
  }

  @Override
  public void mouseClicked(MouseEvent e) {
    Point p = new Point(e.getX(), e.getY());
    clicks.add(p);
    repaint();
  }

  @Override
  public void mouseEntered(MouseEvent e) {
  }

  @Override
  public void mouseExited(MouseEvent e) {
  }

  @Override
  public void mousePressed(MouseEvent e) {
  }

  @Override
  public void mouseReleased(MouseEvent e) {
  }
}

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