text.txt

import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;

import java.io.*;

import javax.imageio.ImageIO;

import javax.swing.*;

public class ImageHiding extends JFrame implements ActionListener
{
	BufferedImage hostImage;
	BufferedImage secretImage;

	JPanel controlPanel;
	JPanel imagePanel;

	JTextField encodeBitsText;
	JButton encodeBitsPlus;
	JButton encodeBitsMinus;

	JTextField nBitsText;
	JButton nBitsPlus;
	JButton nBitsMinus;

	ImageCanvas hostCanvas;
	ImageCanvas secretCanvas;

	Steganography s;

	public BufferedImage getHostImage()
	{
		BufferedImage img = null;

		try
		{
			img = ImageIO.read(new File("host_image.jpg"));
		}
		catch (IOException ioe) { ioe.printStackTrace(); }

		return img;
	}

	public BufferedImage getSecretImage()
	{
		BufferedImage img = null;

		try
		{
			img = ImageIO.read(new File("secret_image.jpg"));
		}
		catch (IOException ioe) { ioe.printStackTrace(); }

		return img;
	}

	public int getBits()
	{
		return Integer.parseInt(encodeBitsText.getText());
	}

	public void actionPerformed(ActionEvent event)
	{
		Object source = event.getSource();

		if (source == encodeBitsPlus)
		{
			int bits = this.getBits() + 1;

			if (bits > 8) { bits = 8; }

			encodeBitsText.setText(Integer.toString(bits));

			s = new Steganography(this.getHostImage());
			s.encode(this.getSecretImage(), bits);

			hostCanvas.setImage(s.getImage());
			hostCanvas.repaint();

			s = new Steganography(this.getSecretImage());
			s.getMaskedImage(bits);

			secretCanvas.setImage(s.getImage());
			secretCanvas.repaint();
		}
		else if (source == encodeBitsMinus)
		{
			int bits = this.getBits() - 1;

			if (bits < 0) { bits = 0; }

			encodeBitsText.setText(Integer.toString(bits));

			s = new Steganography(this.getHostImage());
			s.encode(this.getSecretImage(), bits);

			hostCanvas.setImage(s.getImage());
			hostCanvas.repaint();

			s = new Steganography(this.getSecretImage());
			s.getMaskedImage(bits);

			secretCanvas.setImage(s.getImage());
			secretCanvas.repaint();
		}
	}

	public ImageHiding()
	{
		GridBagLayout layout = new GridBagLayout();
		GridBagConstraints gbc = new GridBagConstraints();
		this.setTitle("Question 1");

		Container container = this.getContentPane();

		this.setLayout(layout);

		this.add(new JLabel("Bits to encode into host image:"));

		encodeBitsText = new JTextField("0", 5);
		encodeBitsText.setEditable(false);

		gbc.weightx = -1.0;
		layout.setConstraints(encodeBitsText, gbc);
		this.add(encodeBitsText);

		encodeBitsPlus = new JButton("+");
		encodeBitsPlus.addActionListener(this);

		encodeBitsMinus = new JButton("-");
		encodeBitsMinus.addActionListener(this);

		gbc.weightx = 1.0;
		layout.setConstraints(encodeBitsPlus, gbc);
		this.add(encodeBitsPlus);

		gbc.gridwidth = GridBagConstraints.REMAINDER;
		layout.setConstraints(encodeBitsMinus, gbc);
		this.add(encodeBitsMinus);

		GridBagLayout imageGridbag = new GridBagLayout();
		GridBagConstraints imageGBC = new GridBagConstraints();

		imagePanel = new JPanel();
		imagePanel.setLayout(imageGridbag);

		JLabel hostImageLabel = new JLabel("Host image:");
		JLabel secretImageLabel = new JLabel("Secret image:");

		imagePanel.add(hostImageLabel);

		imageGBC.gridwidth = GridBagConstraints.REMAINDER;
		imageGridbag.setConstraints(secretImageLabel, imageGBC);
		imagePanel.add(secretImageLabel);

		hostCanvas = new ImageCanvas(this.getHostImage());		
		secretCanvas = new ImageCanvas(this.getSecretImage());

		imagePanel.add(hostCanvas);
		imagePanel.add(secretCanvas);

		gbc.gridwidth = GridBagConstraints.REMAINDER;
		layout.setConstraints(imagePanel, gbc);
		this.add(imagePanel);

		Steganography host = new Steganography(this.getHostImage());
		host.encode(this.getSecretImage(), this.getBits());
		hostCanvas.setImage(host.getImage());

		Steganography secret = new Steganography(this.getSecretImage());
		secret.getMaskedImage(this.getBits());
		secretCanvas.setImage(secret.getImage());

		this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		this.pack();

		this.setVisible(true);
	}

	public static void main(String[] args)
	{
		ImageHiding frame = new ImageHiding();
		frame.setVisible(true);
	}

	public class ImageCanvas extends JPanel
	{	
		Image img;

		public void paintComponent(Graphics g)
		{
			g.drawImage(img, 0, 0, this);
		}

		public void setImage(Image img)
		{
			this.img = img;
		}

		public ImageCanvas(Image img)
		{
			this.img = img;

			this.setPreferredSize(new Dimension(img.getWidth(this), img.getHeight(this)));
		}
	}
}

class Steganography
{
	BufferedImage image;

	public void getMaskedImage(int bits)
	{
		int[] imageRGB = image.getRGB(0, 0, image.getWidth(null), image.getHeight(null), null, 0, image.getWidth(null));

		int maskBits = (int)(Math.pow(2, bits)) - 1 << (8 - bits);
		int mask = (maskBits << 24) | (maskBits << 16) | (maskBits << 8) | maskBits;

		for (int i = 0; i < imageRGB.length; i++)
		{
			imageRGB[i] = imageRGB[i] & mask;
		}

		image.setRGB(0, 0, image.getWidth(null), image.getHeight(null), imageRGB, 0, image.getWidth(null));
	}

	public void encode(BufferedImage encodeImage, int encodeBits)
	{
		int[] encodeRGB = encodeImage.getRGB(0, 0, encodeImage.getWidth(null), encodeImage.getHeight(null), null, 0, encodeImage.getWidth(null));
		int[] imageRGB = image.getRGB(0, 0, image.getWidth(null), image.getHeight(null), null, 0, image.getWidth(null));

		int encodeByteMask = (int)(Math.pow(2, encodeBits)) - 1 << (8 - encodeBits);
		int encodeMask = (encodeByteMask << 24) | (encodeByteMask << 16) | (encodeByteMask << 8) | encodeByteMask;

		int decodeByteMask = ~(encodeByteMask >>> (8 - encodeBits)) & 0xFF;
		int hostMask = (decodeByteMask << 24) | (decodeByteMask << 16) | (decodeByteMask << 8) | decodeByteMask;

		for (int i = 0; i < imageRGB.length; i++)
		{
			int encodeData = (encodeRGB[i] & encodeMask) >>> (8 - encodeBits);
			imageRGB[i] = (imageRGB[i] & hostMask) | (encodeData & ~hostMask);
		}

		image.setRGB(0, 0, image.getWidth(null), image.getHeight(null), imageRGB, 0, image.getWidth(null));
	}

	public Image getImage()
	{
		return image;
	}

	public Steganography(BufferedImage image)
	{
		this.image = image;
	}
}

import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;

import java.io.*;

import javax.imageio.ImageIO;

import javax.swing.*;

public class ImageHiding extends JFrame implements ActionListener
{
	BufferedImage hostImage;
	BufferedImage secretImage;

	JPanel controlPanel;
	JPanel imagePanel;

	JTextField encodeBitsText;
	JButton encodeBitsPlus;
	JButton encodeBitsMinus;

	JTextField nBitsText;
	JButton nBitsPlus;
	JButton nBitsMinus;

	ImageCanvas hostCanvas;
	ImageCanvas secretCanvas;

	Steganography s;

	public BufferedImage getHostImage()
	{
		BufferedImage img = null;

		try
		{
			img = ImageIO.read(new File("host_image.jpg"));
		}
		catch (IOException ioe) { ioe.printStackTrace(); }

		return img;
	}

	public BufferedImage getSecretImage()
	{
		BufferedImage img = null;

		try
		{
			img = ImageIO.read(new File("secret_image.jpg"));
		}
		catch (IOException ioe) { ioe.printStackTrace(); }

		return img;
	}

	public int getBits()
	{
		return Integer.parseInt(encodeBitsText.getText());
	}

	public void actionPerformed(ActionEvent event)
	{
		Object source = event.getSource();

		if (source == encodeBitsPlus)
		{
			int bits = this.getBits() + 1;

			if (bits > 8) { bits = 8; }

			encodeBitsText.setText(Integer.toString(bits));

			s = new Steganography(this.getHostImage());
			s.encode(this.getSecretImage(), bits);

			hostCanvas.setImage(s.getImage());
			hostCanvas.repaint();

			s = new Steganography(this.getSecretImage());
			s.getMaskedImage(bits);

			secretCanvas.setImage(s.getImage());
			secretCanvas.repaint();
		}
		else if (source == encodeBitsMinus)
		{
			int bits = this.getBits() - 1;

			if (bits < 0) { bits = 0; }

			encodeBitsText.setText(Integer.toString(bits));

			s = new Steganography(this.getHostImage());
			s.encode(this.getSecretImage(), bits);

			hostCanvas.setImage(s.getImage());
			hostCanvas.repaint();

			s = new Steganography(this.getSecretImage());
			s.getMaskedImage(bits);

			secretCanvas.setImage(s.getImage());
			secretCanvas.repaint();
		}
	}

	public ImageHiding()
	{
		GridBagLayout layout = new GridBagLayout();
		GridBagConstraints gbc = new GridBagConstraints();
		this.setTitle("Question 1");

		Container container = this.getContentPane();

		this.setLayout(layout);

		this.add(new JLabel("Bits to encode into host image:"));

		encodeBitsText = new JTextField("0", 5);
		encodeBitsText.setEditable(false);

		gbc.weightx = -1.0;
		layout.setConstraints(encodeBitsText, gbc);
		this.add(encodeBitsText);

		encodeBitsPlus = new JButton("+");
		encodeBitsPlus.addActionListener(this);

		encodeBitsMinus = new JButton("-");
		encodeBitsMinus.addActionListener(this);

		gbc.weightx = 1.0;
		layout.setConstraints(encodeBitsPlus, gbc);
		this.add(encodeBitsPlus);

		gbc.gridwidth = GridBagConstraints.REMAINDER;
		layout.setConstraints(encodeBitsMinus, gbc);
		this.add(encodeBitsMinus);

		GridBagLayout imageGridbag = new GridBagLayout();
		GridBagConstraints imageGBC = new GridBagConstraints();

		imagePanel = new JPanel();
		imagePanel.setLayout(imageGridbag);

		JLabel hostImageLabel = new JLabel("Host image:");
		JLabel secretImageLabel = new JLabel("Secret image:");

		imagePanel.add(hostImageLabel);

		imageGBC.gridwidth = GridBagConstraints.REMAINDER;
		imageGridbag.setConstraints(secretImageLabel, imageGBC);
		imagePanel.add(secretImageLabel);

		hostCanvas = new ImageCanvas(this.getHostImage());		
		secretCanvas = new ImageCanvas(this.getSecretImage());

		imagePanel.add(hostCanvas);
		imagePanel.add(secretCanvas);

		gbc.gridwidth = GridBagConstraints.REMAINDER;
		layout.setConstraints(imagePanel, gbc);
		this.add(imagePanel);

		Steganography host = new Steganography(this.getHostImage());
		host.encode(this.getSecretImage(), this.getBits());
		hostCanvas.setImage(host.getImage());

		Steganography secret = new Steganography(this.getSecretImage());
		secret.getMaskedImage(this.getBits());
		secretCanvas.setImage(secret.getImage());

		this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		this.pack();

		this.setVisible(true);
	}

	public static void main(String[] args)
	{
		ImageHiding frame = new ImageHiding();
		frame.setVisible(true);
	}

	public class ImageCanvas extends JPanel
	{	
		Image img;

		public void paintComponent(Graphics g)
		{
			g.drawImage(img, 0, 0, this);
		}

		public void setImage(Image img)
		{
			this.img = img;
		}

		public ImageCanvas(Image img)
		{
			this.img = img;

			this.setPreferredSize(new Dimension(img.getWidth(this), img.getHeight(this)));
		}
	}
}

class Steganography
{
	BufferedImage image;

	public void getMaskedImage(int bits)
	{
		int[] imageRGB = image.getRGB(0, 0, image.getWidth(null), image.getHeight(null), null, 0, image.getWidth(null));

		int maskBits = (int)(Math.pow(2, bits)) - 1 << (8 - bits);
		int mask = (maskBits << 24) | (maskBits << 16) | (maskBits << 8) | maskBits;

		for (int i = 0; i < imageRGB.length; i++)
		{
			imageRGB[i] = imageRGB[i] & mask;
		}

		image.setRGB(0, 0, image.getWidth(null), image.getHeight(null), imageRGB, 0, image.getWidth(null));
	}

	public void encode(BufferedImage encodeImage, int encodeBits)
	{
		int[] encodeRGB = encodeImage.getRGB(0, 0, encodeImage.getWidth(null), encodeImage.getHeight(null), null, 0, encodeImage.getWidth(null));
		int[] imageRGB = image.getRGB(0, 0, image.getWidth(null), image.getHeight(null), null, 0, image.getWidth(null));

		int encodeByteMask = (int)(Math.pow(2, encodeBits)) - 1 << (8 - encodeBits);
		int encodeMask = (encodeByteMask << 24) | (encodeByteMask << 16) | (encodeByteMask << 8) | encodeByteMask;

		int decodeByteMask = ~(encodeByteMask >>> (8 - encodeBits)) & 0xFF;
		int hostMask = (decodeByteMask << 24) | (decodeByteMask << 16) | (decodeByteMask << 8) | decodeByteMask;

		for (int i = 0; i < imageRGB.length; i++)
		{
			int encodeData = (encodeRGB[i] & encodeMask) >>> (8 - encodeBits);
			imageRGB[i] = (imageRGB[i] & hostMask) | (encodeData & ~hostMask);
		}

		image.setRGB(0, 0, image.getWidth(null), image.getHeight(null), imageRGB, 0, image.getWidth(null));
	}

	public Image getImage()
	{
		return image;
	}

	public Steganography(BufferedImage image)
	{
		this.image = image;
	}
}

import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;

import java.io.*;

import javax.imageio.ImageIO;

import javax.swing.*;

public class ImageHiding extends JFrame implements ActionListener
{
	BufferedImage hostImage;
	BufferedImage secretImage;

	JPanel controlPanel;
	JPanel imagePanel;

	JTextField encodeBitsText;
	JButton encodeBitsPlus;
	JButton encodeBitsMinus;

	JTextField nBitsText;
	JButton nBitsPlus;
	JButton nBitsMinus;

	ImageCanvas hostCanvas;
	ImageCanvas secretCanvas;

	Steganography s;

	public BufferedImage getHostImage()
	{
		BufferedImage img = null;

		try
		{
			img = ImageIO.read(new File("host_image.jpg"));
		}
		catch (IOException ioe) { ioe.printStackTrace(); }

		return img;
	}

	public BufferedImage getSecretImage()
	{
		BufferedImage img = null;

		try
		{
			img = ImageIO.read(new File("secret_image.jpg"));
		}
		catch (IOException ioe) { ioe.printStackTrace(); }

		return img;
	}

	public int getBits()
	{
		return Integer.parseInt(encodeBitsText.getText());
	}

	public void actionPerformed(ActionEvent event)
	{
		Object source = event.getSource();

		if (source == encodeBitsPlus)
		{
			int bits = this.getBits() + 1;

			if (bits > 8) { bits = 8; }

			encodeBitsText.setText(Integer.toString(bits));

			s = new Steganography(this.getHostImage());
			s.encode(this.getSecretImage(), bits);

			hostCanvas.setImage(s.getImage());
			hostCanvas.repaint();

			s = new Steganography(this.getSecretImage());
			s.getMaskedImage(bits);

			secretCanvas.setImage(s.getImage());
			secretCanvas.repaint();
		}
		else if (source == encodeBitsMinus)
		{
			int bits = this.getBits() - 1;

			if (bits < 0) { bits = 0; }

			encodeBitsText.setText(Integer.toString(bits));

			s = new Steganography(this.getHostImage());
			s.encode(this.getSecretImage(), bits);

			hostCanvas.setImage(s.getImage());
			hostCanvas.repaint();

			s = new Steganography(this.getSecretImage());
			s.getMaskedImage(bits);

			secretCanvas.setImage(s.getImage());
			secretCanvas.repaint();
		}
	}

	public ImageHiding()
	{
		GridBagLayout layout = new GridBagLayout();
		GridBagConstraints gbc = new GridBagConstraints();
		this.setTitle("Question 1");

		Container container = this.getContentPane();

		this.setLayout(layout);

		this.add(new JLabel("Bits to encode into host image:"));

		encodeBitsText = new JTextField("0", 5);
		encodeBitsText.setEditable(false);

		gbc.weightx = -1.0;
		layout.setConstraints(encodeBitsText, gbc);
		this.add(encodeBitsText);

		encodeBitsPlus = new JButton("+");
		encodeBitsPlus.addActionListener(this);

		encodeBitsMinus = new JButton("-");
		encodeBitsMinus.addActionListener(this);

		gbc.weightx = 1.0;
		layout.setConstraints(encodeBitsPlus, gbc);
		this.add(encodeBitsPlus);

		gbc.gridwidth = GridBagConstraints.REMAINDER;
		layout.setConstraints(encodeBitsMinus, gbc);
		this.add(encodeBitsMinus);

		GridBagLayout imageGridbag = new GridBagLayout();
		GridBagConstraints imageGBC = new GridBagConstraints();

		imagePanel = new JPanel();
		imagePanel.setLayout(imageGridbag);

		JLabel hostImageLabel = new JLabel("Host image:");
		JLabel secretImageLabel = new JLabel("Secret image:");

		imagePanel.add(hostImageLabel);

		imageGBC.gridwidth = GridBagConstraints.REMAINDER;
		imageGridbag.setConstraints(secretImageLabel, imageGBC);
		imagePanel.add(secretImageLabel);

		hostCanvas = new ImageCanvas(this.getHostImage());		
		secretCanvas = new ImageCanvas(this.getSecretImage());

		imagePanel.add(hostCanvas);
		imagePanel.add(secretCanvas);

		gbc.gridwidth = GridBagConstraints.REMAINDER;
		layout.setConstraints(imagePanel, gbc);
		this.add(imagePanel);

		Steganography host = new Steganography(this.getHostImage());
		host.encode(this.getSecretImage(), this.getBits());
		hostCanvas.setImage(host.getImage());

		Steganography secret = new Steganography(this.getSecretImage());
		secret.getMaskedImage(this.getBits());
		secretCanvas.setImage(secret.getImage());

		this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		this.pack();

		this.setVisible(true);
	}

	public static void main(String[] args)
	{
		ImageHiding frame = new ImageHiding();
		frame.setVisible(true);
	}

	public class ImageCanvas extends JPanel
	{	
		Image img;

		public void paintComponent(Graphics g)
		{
			g.drawImage(img, 0, 0, this);
		}

		public void setImage(Image img)
		{
			this.img = img;
		}

		public ImageCanvas(Image img)
		{
			this.img = img;

			this.setPreferredSize(new Dimension(img.getWidth(this), img.getHeight(this)));
		}
	}
}

class Steganography
{
	BufferedImage image;

	public void getMaskedImage(int bits)
	{
		int[] imageRGB = image.getRGB(0, 0, image.getWidth(null), image.getHeight(null), null, 0, image.getWidth(null));

		int maskBits = (int)(Math.pow(2, bits)) - 1 << (8 - bits);
		int mask = (maskBits << 24) | (maskBits << 16) | (maskBits << 8) | maskBits;

		for (int i = 0; i < imageRGB.length; i++)
		{
			imageRGB[i] = imageRGB[i] & mask;
		}

		image.setRGB(0, 0, image.getWidth(null), image.getHeight(null), imageRGB, 0, image.getWidth(null));
	}

	public void encode(BufferedImage encodeImage, int encodeBits)
	{
		int[] encodeRGB = encodeImage.getRGB(0, 0, encodeImage.getWidth(null), encodeImage.getHeight(null), null, 0, encodeImage.getWidth(null));
		int[] imageRGB = image.getRGB(0, 0, image.getWidth(null), image.getHeight(null), null, 0, image.getWidth(null));

		int encodeByteMask = (int)(Math.pow(2, encodeBits)) - 1 << (8 - encodeBits);
		int encodeMask = (encodeByteMask << 24) | (encodeByteMask << 16) | (encodeByteMask << 8) | encodeByteMask;

		int decodeByteMask = ~(encodeByteMask >>> (8 - encodeBits)) & 0xFF;
		int hostMask = (decodeByteMask << 24) | (decodeByteMask << 16) | (decodeByteMask << 8) | decodeByteMask;

		for (int i = 0; i < imageRGB.length; i++)
		{
			int encodeData = (encodeRGB[i] & encodeMask) >>> (8 - encodeBits);
			imageRGB[i] = (imageRGB[i] & hostMask) | (encodeData & ~hostMask);
		}

		image.setRGB(0, 0, image.getWidth(null), image.getHeight(null), imageRGB, 0, image.getWidth(null));
	}

	public Image getImage()
	{
		return image;
	}

	public Steganography(BufferedImage image)
	{
		this.image = image;
	}
}

import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;

import java.io.*;

import javax.imageio.ImageIO;

import javax.swing.*;

public class ImageHiding extends JFrame implements ActionListener
{
	BufferedImage hostImage;
	BufferedImage secretImage;

	JPanel controlPanel;
	JPanel imagePanel;

	JTextField encodeBitsText;
	JButton encodeBitsPlus;
	JButton encodeBitsMinus;

	JTextField nBitsText;
	JButton nBitsPlus;
	JButton nBitsMinus;

	ImageCanvas hostCanvas;
	ImageCanvas secretCanvas;

	Steganography s;

	public BufferedImage getHostImage()
	{
		BufferedImage img = null;

		try
		{
			img = ImageIO.read(new File("host_image.jpg"));
		}
		catch (IOException ioe) { ioe.printStackTrace(); }

		return img;
	}

	public BufferedImage getSecretImage()
	{
		BufferedImage img = null;

		try
		{
			img = ImageIO.read(new File("secret_image.jpg"));
		}
		catch (IOException ioe) { ioe.printStackTrace(); }

		return img;
	}

	public int getBits()
	{
		return Integer.parseInt(encodeBitsText.getText());
	}

	public void actionPerformed(ActionEvent event)
	{
		Object source = event.getSource();

		if (source == encodeBitsPlus)
		{
			int bits = this.getBits() + 1;

			if (bits > 8) { bits = 8; }

			encodeBitsText.setText(Integer.toString(bits));

			s = new Steganography(this.getHostImage());
			s.encode(this.getSecretImage(), bits);

			hostCanvas.setImage(s.getImage());
			hostCanvas.repaint();

			s = new Steganography(this.getSecretImage());
			s.getMaskedImage(bits);

			secretCanvas.setImage(s.getImage());
			secretCanvas.repaint();
		}
		else if (source == encodeBitsMinus)
		{
			int bits = this.getBits() - 1;

			if (bits < 0) { bits = 0; }

			encodeBitsText.setText(Integer.toString(bits));

			s = new Steganography(this.getHostImage());
			s.encode(this.getSecretImage(), bits);

			hostCanvas.setImage(s.getImage());
			hostCanvas.repaint();

			s = new Steganography(this.getSecretImage());
			s.getMaskedImage(bits);

			secretCanvas.setImage(s.getImage());
			secretCanvas.repaint();
		}
	}

	public ImageHiding()
	{
		GridBagLayout layout = new GridBagLayout();
		GridBagConstraints gbc = new GridBagConstraints();
		this.setTitle("Question 1");

		Container container = this.getContentPane();

		this.setLayout(layout);

		this.add(new JLabel("Bits to encode into host image:"));

		encodeBitsText = new JTextField("0", 5);
		encodeBitsText.setEditable(false);

		gbc.weightx = -1.0;
		layout.setConstraints(encodeBitsText, gbc);
		this.add(encodeBitsText);

		encodeBitsPlus = new JButton("+");
		encodeBitsPlus.addActionListener(this);

		encodeBitsMinus = new JButton("-");
		encodeBitsMinus.addActionListener(this);

		gbc.weightx = 1.0;
		layout.setConstraints(encodeBitsPlus, gbc);
		this.add(encodeBitsPlus);

		gbc.gridwidth = GridBagConstraints.REMAINDER;
		layout.setConstraints(encodeBitsMinus, gbc);
		this.add(encodeBitsMinus);

		GridBagLayout imageGridbag = new GridBagLayout();
		GridBagConstraints imageGBC = new GridBagConstraints();

		imagePanel = new JPanel();
		imagePanel.setLayout(imageGridbag);

		JLabel hostImageLabel = new JLabel("Host image:");
		JLabel secretImageLabel = new JLabel("Secret image:");

		imagePanel.add(hostImageLabel);

		imageGBC.gridwidth = GridBagConstraints.REMAINDER;
		imageGridbag.setConstraints(secretImageLabel, imageGBC);
		imagePanel.add(secretImageLabel);

		hostCanvas = new ImageCanvas(this.getHostImage());		
		secretCanvas = new ImageCanvas(this.getSecretImage());

		imagePanel.add(hostCanvas);
		imagePanel.add(secretCanvas);

		gbc.gridwidth = GridBagConstraints.REMAINDER;
		layout.setConstraints(imagePanel, gbc);
		this.add(imagePanel);

		Steganography host = new Steganography(this.getHostImage());
		host.encode(this.getSecretImage(), this.getBits());
		hostCanvas.setImage(host.getImage());

		Steganography secret = new Steganography(this.getSecretImage());
		secret.getMaskedImage(this.getBits());
		secretCanvas.setImage(secret.getImage());

		this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		this.pack();

		this.setVisible(true);
	}

	public static void main(String[] args)
	{
		ImageHiding frame = new ImageHiding();
		frame.setVisible(true);
	}

	public class ImageCanvas extends JPanel
	{	
		Image img;

		public void paintComponent(Graphics g)
		{
			g.drawImage(img, 0, 0, this);
		}

		public void setImage(Image img)
		{
			this.img = img;
		}

		public ImageCanvas(Image img)
		{
			this.img = img;

			this.setPreferredSize(new Dimension(img.getWidth(this), img.getHeight(this)));
		}
	}
}

class Steganography
{
	BufferedImage image;

	public void getMaskedImage(int bits)
	{
		int[] imageRGB = image.getRGB(0, 0, image.getWidth(null), image.getHeight(null), null, 0, image.getWidth(null));

		int maskBits = (int)(Math.pow(2, bits)) - 1 << (8 - bits);
		int mask = (maskBits << 24) | (maskBits << 16) | (maskBits << 8) | maskBits;

		for (int i = 0; i < imageRGB.length; i++)
		{
			imageRGB[i] = imageRGB[i] & mask;
		}

		image.setRGB(0, 0, image.getWidth(null), image.getHeight(null), imageRGB, 0, image.getWidth(null));
	}

	public void encode(BufferedImage encodeImage, int encodeBits)
	{
		int[] encodeRGB = encodeImage.getRGB(0, 0, encodeImage.getWidth(null), encodeImage.getHeight(null), null, 0, encodeImage.getWidth(null));
		int[] imageRGB = image.getRGB(0, 0, image.getWidth(null), image.getHeight(null), null, 0, image.getWidth(null));

		int encodeByteMask = (int)(Math.pow(2, encodeBits)) - 1 << (8 - encodeBits);
		int encodeMask = (encodeByteMask << 24) | (encodeByteMask << 16) | (encodeByteMask << 8) | encodeByteMask;

		int decodeByteMask = ~(encodeByteMask >>> (8 - encodeBits)) & 0xFF;
		int hostMask = (decodeByteMask << 24) | (decodeByteMask << 16) | (decodeByteMask << 8) | decodeByteMask;

		for (int i = 0; i < imageRGB.length; i++)
		{
			int encodeData = (encodeRGB[i] & encodeMask) >>> (8 - encodeBits);
			imageRGB[i] = (imageRGB[i] & hostMask) | (encodeData & ~hostMask);
		}

		image.setRGB(0, 0, image.getWidth(null), image.getHeight(null), imageRGB, 0, image.getWidth(null));
	}

	public Image getImage()
	{
		return image;
	}

	public Steganography(BufferedImage image)
	{
		this.image = image;
	}
}

import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;

import java.io.*;

import javax.imageio.ImageIO;

import javax.swing.*;

public class ImageHiding extends JFrame implements ActionListener
{
	BufferedImage hostImage;
	BufferedImage secretImage;

	JPanel controlPanel;
	JPanel imagePanel;

	JTextField encodeBitsText;
	JButton encodeBitsPlus;
	JButton encodeBitsMinus;

	JTextField nBitsText;
	JButton nBitsPlus;
	JButton nBitsMinus;

	ImageCanvas hostCanvas;
	ImageCanvas secretCanvas;

	Steganography s;

	public BufferedImage getHostImage()
	{
		BufferedImage img = null;

		try
		{
			img = ImageIO.read(new File("host_image.jpg"));
		}
		catch (IOException ioe) { ioe.printStackTrace(); }

		return img;
	}

	public BufferedImage getSecretImage()
	{
		BufferedImage img = null;

		try
		{
			img = ImageIO.read(new File("secret_image.jpg"));
		}
		catch (IOException ioe) { ioe.printStackTrace(); }

		return img;
	}

	public int getBits()
	{
		return Integer.parseInt(encodeBitsText.getText());
	}

	public void actionPerformed(ActionEvent event)
	{
		Object source = event.getSource();

		if (source == encodeBitsPlus)
		{
			int bits = this.getBits() + 1;

			if (bits > 8) { bits = 8; }

			encodeBitsText.setText(Integer.toString(bits));

			s = new Steganography(this.getHostImage());
			s.encode(this.getSecretImage(), bits);

			hostCanvas.setImage(s.getImage());
			hostCanvas.repaint();

			s = new Steganography(this.getSecretImage());
			s.getMaskedImage(bits);

			secretCanvas.setImage(s.getImage());
			secretCanvas.repaint();
		}
		else if (source == encodeBitsMinus)
		{
			int bits = this.getBits() - 1;

			if (bits < 0) { bits = 0; }

			encodeBitsText.setText(Integer.toString(bits));

			s = new Steganography(this.getHostImage());
			s.encode(this.getSecretImage(), bits);

			hostCanvas.setImage(s.getImage());
			hostCanvas.repaint();

			s = new Steganography(this.getSecretImage());
			s.getMaskedImage(bits);

			secretCanvas.setImage(s.getImage());
			secretCanvas.repaint();
		}
	}

	public ImageHiding()
	{
		GridBagLayout layout = new GridBagLayout();
		GridBagConstraints gbc = new GridBagConstraints();
		this.setTitle("Question 1");

		Container container = this.getContentPane();

		this.setLayout(layout);

		this.add(new JLabel("Bits to encode into host image:"));

		encodeBitsText = new JTextField("0", 5);
		encodeBitsText.setEditable(false);

		gbc.weightx = -1.0;
		layout.setConstraints(encodeBitsText, gbc);
		this.add(encodeBitsText);

		encodeBitsPlus = new JButton("+");
		encodeBitsPlus.addActionListener(this);

		encodeBitsMinus = new JButton("-");
		encodeBitsMinus.addActionListener(this);

		gbc.weightx = 1.0;
		layout.setConstraints(encodeBitsPlus, gbc);
		this.add(encodeBitsPlus);

		gbc.gridwidth = GridBagConstraints.REMAINDER;
		layout.setConstraints(encodeBitsMinus, gbc);
		this.add(encodeBitsMinus);

		GridBagLayout imageGridbag = new GridBagLayout();
		GridBagConstraints imageGBC = new GridBagConstraints();

		imagePanel = new JPanel();
		imagePanel.setLayout(imageGridbag);

		JLabel hostImageLabel = new JLabel("Host image:");
		JLabel secretImageLabel = new JLabel("Secret image:");

		imagePanel.add(hostImageLabel);

		imageGBC.gridwidth = GridBagConstraints.REMAINDER;
		imageGridbag.setConstraints(secretImageLabel, imageGBC);
		imagePanel.add(secretImageLabel);

		hostCanvas = new ImageCanvas(this.getHostImage());		
		secretCanvas = new ImageCanvas(this.getSecretImage());

		imagePanel.add(hostCanvas);
		imagePanel.add(secretCanvas);

		gbc.gridwidth = GridBagConstraints.REMAINDER;
		layout.setConstraints(imagePanel, gbc);
		this.add(imagePanel);

		Steganography host = new Steganography(this.getHostImage());
		host.encode(this.getSecretImage(), this.getBits());
		hostCanvas.setImage(host.getImage());

		Steganography secret = new Steganography(this.getSecretImage());
		secret.getMaskedImage(this.getBits());
		secretCanvas.setImage(secret.getImage());

		this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		this.pack();

		this.setVisible(true);
	}

	public static void main(String[] args)
	{
		ImageHiding frame = new ImageHiding();
		frame.setVisible(true);
	}

	public class ImageCanvas extends JPanel
	{	
		Image img;

		public void paintComponent(Graphics g)
		{
			g.drawImage(img, 0, 0, this);
		}

		public void setImage(Image img)
		{
			this.img = img;
		}

		public ImageCanvas(Image img)
		{
			this.img = img;

			this.setPreferredSize(new Dimension(img.getWidth(this), img.getHeight(this)));
		}
	}
}

class Steganography
{
	BufferedImage image;

	public void getMaskedImage(int bits)
	{
		int[] imageRGB = image.getRGB(0, 0, image.getWidth(null), image.getHeight(null), null, 0, image.getWidth(null));

		int maskBits = (int)(Math.pow(2, bits)) - 1 << (8 - bits);
		int mask = (maskBits << 24) | (maskBits << 16) | (maskBits << 8) | maskBits;

		for (int i = 0; i < imageRGB.length; i++)
		{
			imageRGB[i] = imageRGB[i] & mask;
		}

		image.setRGB(0, 0, image.getWidth(null), image.getHeight(null), imageRGB, 0, image.getWidth(null));
	}

	public void encode(BufferedImage encodeImage, int encodeBits)
	{
		int[] encodeRGB = encodeImage.getRGB(0, 0, encodeImage.getWidth(null), encodeImage.getHeight(null), null, 0, encodeImage.getWidth(null));
		int[] imageRGB = image.getRGB(0, 0, image.getWidth(null), image.getHeight(null), null, 0, image.getWidth(null));

		int encodeByteMask = (int)(Math.pow(2, encodeBits)) - 1 << (8 - encodeBits);
		int encodeMask = (encodeByteMask << 24) | (encodeByteMask << 16) | (encodeByteMask << 8) | encodeByteMask;

		int decodeByteMask = ~(encodeByteMask >>> (8 - encodeBits)) & 0xFF;
		int hostMask = (decodeByteMask << 24) | (decodeByteMask << 16) | (decodeByteMask << 8) | decodeByteMask;

		for (int i = 0; i < imageRGB.length; i++)
		{
			int encodeData = (encodeRGB[i] & encodeMask) >>> (8 - encodeBits);
			imageRGB[i] = (imageRGB[i] & hostMask) | (encodeData & ~hostMask);
		}

		image.setRGB(0, 0, image.getWidth(null), image.getHeight(null), imageRGB, 0, image.getWidth(null));
	}

	public Image getImage()
	{
		return image;
	}

	public Steganography(BufferedImage image)
	{
		this.image = image;
	}
}

import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;

import java.io.*;

import javax.imageio.ImageIO;

import javax.swing.*;

public class ImageHiding extends JFrame implements ActionListener
{
	BufferedImage hostImage;
	BufferedImage secretImage;

	JPanel controlPanel;
	JPanel imagePanel;

	JTextField encodeBitsText;
	JButton encodeBitsPlus;
	JButton encodeBitsMinus;

	JTextField nBitsText;
	JButton nBitsPlus;
	JButton nBitsMinus;

	ImageCanvas hostCanvas;
	ImageCanvas secretCanvas;

	Steganography s;

	public BufferedImage getHostImage()
	{
		BufferedImage img = null;

		try
		{
			img = ImageIO.read(new File("host_image.jpg"));
		}
		catch (IOException ioe) { ioe.printStackTrace(); }

		return img;
	}

	public BufferedImage getSecretImage()
	{
		BufferedImage img = null;

		try
		{
			img = ImageIO.read(new File("secret_image.jpg"));
		}
		catch (IOException ioe) { ioe.printStackTrace(); }

		return img;
	}

	public int getBits()
	{
		return Integer.parseInt(encodeBitsText.getText());
	}

	public void actionPerformed(ActionEvent event)
	{
		Object source = event.getSource();

		if (source == encodeBitsPlus)
		{
			int bits = this.getBits() + 1;

			if (bits > 8) { bits = 8; }

			encodeBitsText.setText(Integer.toString(bits));

			s = new Steganography(this.getHostImage());
			s.encode(this.getSecretImage(), bits);

			hostCanvas.setImage(s.getImage());
			hostCanvas.repaint();

			s = new Steganography(this.getSecretImage());
			s.getMaskedImage(bits);

			secretCanvas.setImage(s.getImage());
			secretCanvas.repaint();
		}
		else if (source == encodeBitsMinus)
		{
			int bits = this.getBits() - 1;

			if (bits < 0) { bits = 0; }

			encodeBitsText.setText(Integer.toString(bits));

			s = new Steganography(this.getHostImage());
			s.encode(this.getSecretImage(), bits);

			hostCanvas.setImage(s.getImage());
			hostCanvas.repaint();

			s = new Steganography(this.getSecretImage());
			s.getMaskedImage(bits);

			secretCanvas.setImage(s.getImage());
			secretCanvas.repaint();
		}
	}

	public ImageHiding()
	{
		GridBagLayout layout = new GridBagLayout();
		GridBagConstraints gbc = new GridBagConstraints();
		this.setTitle("Question 1");

		Container container = this.getContentPane();

		this.setLayout(layout);

		this.add(new JLabel("Bits to encode into host image:"));

		encodeBitsText = new JTextField("0", 5);
		encodeBitsText.setEditable(false);

		gbc.weightx = -1.0;
		layout.setConstraints(encodeBitsText, gbc);
		this.add(encodeBitsText);

		encodeBitsPlus = new JButton("+");
		encodeBitsPlus.addActionListener(this);

		encodeBitsMinus = new JButton("-");
		encodeBitsMinus.addActionListener(this);

		gbc.weightx = 1.0;
		layout.setConstraints(encodeBitsPlus, gbc);
		this.add(encodeBitsPlus);

		gbc.gridwidth = GridBagConstraints.REMAINDER;
		layout.setConstraints(encodeBitsMinus, gbc);
		this.add(encodeBitsMinus);

		GridBagLayout imageGridbag = new GridBagLayout();
		GridBagConstraints imageGBC = new GridBagConstraints();

		imagePanel = new JPanel();
		imagePanel.setLayout(imageGridbag);

		JLabel hostImageLabel = new JLabel("Host image:");
		JLabel secretImageLabel = new JLabel("Secret image:");

		imagePanel.add(hostImageLabel);

		imageGBC.gridwidth = GridBagConstraints.REMAINDER;
		imageGridbag.setConstraints(secretImageLabel, imageGBC);
		imagePanel.add(secretImageLabel);

		hostCanvas = new ImageCanvas(this.getHostImage());		
		secretCanvas = new ImageCanvas(this.getSecretImage());

		imagePanel.add(hostCanvas);
		imagePanel.add(secretCanvas);

		gbc.gridwidth = GridBagConstraints.REMAINDER;
		layout.setConstraints(imagePanel, gbc);
		this.add(imagePanel);

		Steganography host = new Steganography(this.getHostImage());
		host.encode(this.getSecretImage(), this.getBits());
		hostCanvas.setImage(host.getImage());

		Steganography secret = new Steganography(this.getSecretImage());
		secret.getMaskedImage(this.getBits());
		secretCanvas.setImage(secret.getImage());

		this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		this.pack();

		this.setVisible(true);
	}

	public static void main(String[] args)
	{
		ImageHiding frame = new ImageHiding();
		frame.setVisible(true);
	}

	public class ImageCanvas extends JPanel
	{	
		Image img;

		public void paintComponent(Graphics g)
		{
			g.drawImage(img, 0, 0, this);
		}

		public void setImage(Image img)
		{
			this.img = img;
		}

		public ImageCanvas(Image img)
		{
			this.img = img;

			this.setPreferredSize(new Dimension(img.getWidth(this), img.getHeight(this)));
		}
	}
}

class Steganography
{
	BufferedImage image;

	public void getMaskedImage(int bits)
	{
		int[] imageRGB = image.getRGB(0, 0, image.getWidth(null), image.getHeight(null), null, 0, image.getWidth(null));

		int maskBits = (int)(Math.pow(2, bits)) - 1 << (8 - bits);
		int mask = (maskBits << 24) | (maskBits << 16) | (maskBits << 8) | maskBits;

		for (int i = 0; i < imageRGB.length; i++)
		{
			imageRGB[i] = imageRGB[i] & mask;
		}

		image.setRGB(0, 0, image.getWidth(null), image.getHeight(null), imageRGB, 0, image.getWidth(null));
	}

	public void encode(BufferedImage encodeImage, int encodeBits)
	{
		int[] encodeRGB = encodeImage.getRGB(0, 0, encodeImage.getWidth(null), encodeImage.getHeight(null), null, 0, encodeImage.getWidth(null));
		int[] imageRGB = image.getRGB(0, 0, image.getWidth(null), image.getHeight(null), null, 0, image.getWidth(null));

		int encodeByteMask = (int)(Math.pow(2, encodeBits)) - 1 << (8 - encodeBits);
		int encodeMask = (encodeByteMask << 24) | (encodeByteMask << 16) | (encodeByteMask << 8) | encodeByteMask;

		int decodeByteMask = ~(encodeByteMask >>> (8 - encodeBits)) & 0xFF;
		int hostMask = (decodeByteMask << 24) | (decodeByteMask << 16) | (decodeByteMask << 8) | decodeByteMask;

		for (int i = 0; i < imageRGB.length; i++)
		{
			int encodeData = (encodeRGB[i] & encodeMask) >>> (8 - encodeBits);
			imageRGB[i] = (imageRGB[i] & hostMask) | (encodeData & ~hostMask);
		}

		image.setRGB(0, 0, image.getWidth(null), image.getHeight(null), imageRGB, 0, image.getWidth(null));
	}

	public Image getImage()
	{
		return image;
	}

	public Steganography(BufferedImage image)
	{
		this.image = image;
	}
}

import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;

import java.io.*;

import javax.imageio.ImageIO;

import javax.swing.*;

public class ImageHiding extends JFrame implements ActionListener
{
	BufferedImage hostImage;
	BufferedImage secretImage;

	JPanel controlPanel;
	JPanel imagePanel;

	JTextField encodeBitsText;
	JButton encodeBitsPlus;
	JButton encodeBitsMinus;

	JTextField nBitsText;
	JButton nBitsPlus;
	JButton nBitsMinus;

	ImageCanvas hostCanvas;
	ImageCanvas secretCanvas;

	Steganography s;

	public BufferedImage getHostImage()
	{
		BufferedImage img = null;

		try
		{
			img = ImageIO.read(new File("host_image.jpg"));
		}
		catch (IOException ioe) { ioe.printStackTrace(); }

		return img;
	}

	public BufferedImage getSecretImage()
	{
		BufferedImage img = null;

		try
		{
			img = ImageIO.read(new File("secret_image.jpg"));
		}
		catch (IOException ioe) { ioe.printStackTrace(); }

		return img;
	}

	public int getBits()
	{
		return Integer.parseInt(encodeBitsText.getText());
	}

	public void actionPerformed(ActionEvent event)
	{
		Object source = event.getSource();

		if (source == encodeBitsPlus)
		{
			int bits = this.getBits() + 1;

			if (bits > 8) { bits = 8; }

			encodeBitsText.setText(Integer.toString(bits));

			s = new Steganography(this.getHostImage());
			s.encode(this.getSecretImage(), bits);

			hostCanvas.setImage(s.getImage());
			hostCanvas.repaint();

			s = new Steganography(this.getSecretImage());
			s.getMaskedImage(bits);

			secretCanvas.setImage(s.getImage());
			secretCanvas.repaint();
		}
		else if (source == encodeBitsMinus)
		{
			int bits = this.getBits() - 1;

			if (bits < 0) { bits = 0; }

			encodeBitsText.setText(Integer.toString(bits));

			s = new Steganography(this.getHostImage());
			s.encode(this.getSecretImage(), bits);

			hostCanvas.setImage(s.getImage());
			hostCanvas.repaint();

			s = new Steganography(this.getSecretImage());
			s.getMaskedImage(bits);

			secretCanvas.setImage(s.getImage());
			secretCanvas.repaint();
		}
	}

	public ImageHiding()
	{
		GridBagLayout layout = new GridBagLayout();
		GridBagConstraints gbc = new GridBagConstraints();
		this.setTitle("Question 1");

		Container container = this.getContentPane();

		this.setLayout(layout);

		this.add(new JLabel("Bits to encode into host image:"));

		encodeBitsText = new JTextField("0", 5);
		encodeBitsText.setEditable(false);

		gbc.weightx = -1.0;
		layout.setConstraints(encodeBitsText, gbc);
		this.add(encodeBitsText);

		encodeBitsPlus = new JButton("+");
		encodeBitsPlus.addActionListener(this);

		encodeBitsMinus = new JButton("-");
		encodeBitsMinus.addActionListener(this);

		gbc.weightx = 1.0;
		layout.setConstraints(encodeBitsPlus, gbc);
		this.add(encodeBitsPlus);

		gbc.gridwidth = GridBagConstraints.REMAINDER;
		layout.setConstraints(encodeBitsMinus, gbc);
		this.add(encodeBitsMinus);

		GridBagLayout imageGridbag = new GridBagLayout();
		GridBagConstraints imageGBC = new GridBagConstraints();

		imagePanel = new JPanel();
		imagePanel.setLayout(imageGridbag);

		JLabel hostImageLabel = new JLabel("Host image:");
		JLabel secretImageLabel = new JLabel("Secret image:");

		imagePanel.add(hostImageLabel);

		imageGBC.gridwidth = GridBagConstraints.REMAINDER;
		imageGridbag.setConstraints(secretImageLabel, imageGBC);
		imagePanel.add(secretImageLabel);

		hostCanvas = new ImageCanvas(this.getHostImage());		
		secretCanvas = new ImageCanvas(this.getSecretImage());

		imagePanel.add(hostCanvas);
		imagePanel.add(secretCanvas);

		gbc.gridwidth = GridBagConstraints.REMAINDER;
		layout.setConstraints(imagePanel, gbc);
		this.add(imagePanel);

		Steganography host = new Steganography(this.getHostImage());
		host.encode(this.getSecretImage(), this.getBits());
		hostCanvas.setImage(host.getImage());

		Steganography secret = new Steganography(this.getSecretImage());
		secret.getMaskedImage(this.getBits());
		secretCanvas.setImage(secret.getImage());

		this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		this.pack();

		this.setVisible(true);
	}

	public static void main(String[] args)
	{
		ImageHiding frame = new ImageHiding();
		frame.setVisible(true);
	}

	public class ImageCanvas extends JPanel
	{	
		Image img;

		public void paintComponent(Graphics g)
		{
			g.drawImage(img, 0, 0, this);
		}

		public void setImage(Image img)
		{
			this.img = img;
		}

		public ImageCanvas(Image img)
		{
			this.img = img;

			this.setPreferredSize(new Dimension(img.getWidth(this), img.getHeight(this)));
		}
	}
}

class Steganography
{
	BufferedImage image;

	public void getMaskedImage(int bits)
	{
		int[] imageRGB = image.getRGB(0, 0, image.getWidth(null), image.getHeight(null), null, 0, image.getWidth(null));

		int maskBits = (int)(Math.pow(2, bits)) - 1 << (8 - bits);
		int mask = (maskBits << 24) | (maskBits << 16) | (maskBits << 8) | maskBits;

		for (int i = 0; i < imageRGB.length; i++)
		{
			imageRGB[i] = imageRGB[i] & mask;
		}

		image.setRGB(0, 0, image.getWidth(null), image.getHeight(null), imageRGB, 0, image.getWidth(null));
	}

	public void encode(BufferedImage encodeImage, int encodeBits)
	{
		int[] encodeRGB = encodeImage.getRGB(0, 0, encodeImage.getWidth(null), encodeImage.getHeight(null), null, 0, encodeImage.getWidth(null));
		int[] imageRGB = image.getRGB(0, 0, image.getWidth(null), image.getHeight(null), null, 0, image.getWidth(null));

		int encodeByteMask = (int)(Math.pow(2, encodeBits)) - 1 << (8 - encodeBits);
		int encodeMask = (encodeByteMask << 24) | (encodeByteMask << 16) | (encodeByteMask << 8) | encodeByteMask;

		int decodeByteMask = ~(encodeByteMask >>> (8 - encodeBits)) & 0xFF;
		int hostMask = (decodeByteMask << 24) | (decodeByteMask << 16) | (decodeByteMask << 8) | decodeByteMask;

		for (int i = 0; i < imageRGB.length; i++)
		{
			int encodeData = (encodeRGB[i] & encodeMask) >>> (8 - encodeBits);
			imageRGB[i] = (imageRGB[i] & hostMask) | (encodeData & ~hostMask);
		}

		image.setRGB(0, 0, image.getWidth(null), image.getHeight(null), imageRGB, 0, image.getWidth(null));
	}

	public Image getImage()
	{
		return image;
	}

	public Steganography(BufferedImage image)
	{
		this.image = image;
	}
}

import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;

import java.io.*;

import javax.imageio.ImageIO;

import javax.swing.*;

public class ImageHiding extends JFrame implements ActionListener
{
	BufferedImage hostImage;
	BufferedImage secretImage;

	JPanel controlPanel;
	JPanel imagePanel;

	JTextField encodeBitsText;
	JButton encodeBitsPlus;
	JButton encodeBitsMinus;

	JTextField nBitsText;
	JButton nBitsPlus;
	JButton nBitsMinus;

	ImageCanvas hostCanvas;
	ImageCanvas secretCanvas;

	Steganography s;

	public BufferedImage getHostImage()
	{
		BufferedImage img = null;

		try
		{
			img = ImageIO.read(new File("host_image.jpg"));
		}
		catch (IOException ioe) { ioe.printStackTrace(); }

		return img;
	}

	public BufferedImage getSecretImage()
	{
		BufferedImage img = null;

		try
		{
			img = ImageIO.read(new File("secret_image.jpg"));
		}
		catch (IOException ioe) { ioe.printStackTrace(); }

		return img;
	}

	public int getBits()
	{
		return Integer.parseInt(encodeBitsText.getText());
	}

	public void actionPerformed(ActionEvent event)
	{
		Object source = event.getSource();

		if (source == encodeBitsPlus)
		{
			int bits = this.getBits() + 1;

			if (bits > 8) { bits = 8; }

			encodeBitsText.setText(Integer.toString(bits));

			s = new Steganography(this.getHostImage());
			s.encode(this.getSecretImage(), bits);

			hostCanvas.setImage(s.getImage());
			hostCanvas.repaint();

			s = new Steganography(this.getSecretImage());
			s.getMaskedImage(bits);

			secretCanvas.setImage(s.getImage());
			secretCanvas.repaint();
		}
		else if (source == encodeBitsMinus)
		{
			int bits = this.getBits() - 1;

			if (bits < 0) { bits = 0; }

			encodeBitsText.setText(Integer.toString(bits));

			s = new Steganography(this.getHostImage());
			s.encode(this.getSecretImage(), bits);

			hostCanvas.setImage(s.getImage());
			hostCanvas.repaint();

			s = new Steganography(this.getSecretImage());
			s.getMaskedImage(bits);

			secretCanvas.setImage(s.getImage());
			secretCanvas.repaint();
		}
	}

	public ImageHiding()
	{
		GridBagLayout layout = new GridBagLayout();
		GridBagConstraints gbc = new GridBagConstraints();
		this.setTitle("Question 1");

		Container container = this.getContentPane();

		this.setLayout(layout);

		this.add(new JLabel("Bits to encode into host image:"));

		encodeBitsText = new JTextField("0", 5);
		encodeBitsText.setEditable(false);

		gbc.weightx = -1.0;
		layout.setConstraints(encodeBitsText, gbc);
		this.add(encodeBitsText);

		encodeBitsPlus = new JButton("+");
		encodeBitsPlus.addActionListener(this);

		encodeBitsMinus = new JButton("-");
		encodeBitsMinus.addActionListener(this);

		gbc.weightx = 1.0;
		layout.setConstraints(encodeBitsPlus, gbc);
		this.add(encodeBitsPlus);

		gbc.gridwidth = GridBagConstraints.REMAINDER;
		layout.setConstraints(encodeBitsMinus, gbc);
		this.add(encodeBitsMinus);

		GridBagLayout imageGridbag = new GridBagLayout();
		GridBagConstraints imageGBC = new GridBagConstraints();

		imagePanel = new JPanel();
		imagePanel.setLayout(imageGridbag);

		JLabel hostImageLabel = new JLabel("Host image:");
		JLabel secretImageLabel = new JLabel("Secret image:");

		imagePanel.add(hostImageLabel);

		imageGBC.gridwidth = GridBagConstraints.REMAINDER;
		imageGridbag.setConstraints(secretImageLabel, imageGBC);
		imagePanel.add(secretImageLabel);

		hostCanvas = new ImageCanvas(this.getHostImage());		
		secretCanvas = new ImageCanvas(this.getSecretImage());

		imagePanel.add(hostCanvas);
		imagePanel.add(secretCanvas);

		gbc.gridwidth = GridBagConstraints.REMAINDER;
		layout.setConstraints(imagePanel, gbc);
		this.add(imagePanel);

		Steganography host = new Steganography(this.getHostImage());
		host.encode(this.getSecretImage(), this.getBits());
		hostCanvas.setImage(host.getImage());

		Steganography secret = new Steganography(this.getSecretImage());
		secret.getMaskedImage(this.getBits());
		secretCanvas.setImage(secret.getImage());

		this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		this.pack();

		this.setVisible(true);
	}

	public static void main(String[] args)
	{
		ImageHiding frame = new ImageHiding();
		frame.setVisible(true);
	}

	public class ImageCanvas extends JPanel
	{	
		Image img;

		public void paintComponent(Graphics g)
		{
			g.drawImage(img, 0, 0, this);
		}

		public void setImage(Image img)
		{
			this.img = img;
		}

		public ImageCanvas(Image img)
		{
			this.img = img;

			this.setPreferredSize(new Dimension(img.getWidth(this), img.getHeight(this)));
		}
	}
}

class Steganography
{
	BufferedImage image;

	public void getMaskedImage(int bits)
	{
		int[] imageRGB = image.getRGB(0, 0, image.getWidth(null), image.getHeight(null), null, 0, image.getWidth(null));

		int maskBits = (int)(Math.pow(2, bits)) - 1 << (8 - bits);
		int mask = (maskBits << 24) | (maskBits << 16) | (maskBits << 8) | maskBits;

		for (int i = 0; i < imageRGB.length; i++)
		{
			imageRGB[i] = imageRGB[i] & mask;
		}

		image.setRGB(0, 0, image.getWidth(null), image.getHeight(null), imageRGB, 0, image.getWidth(null));
	}

	public void encode(BufferedImage encodeImage, int encodeBits)
	{
		int[] encodeRGB = encodeImage.getRGB(0, 0, encodeImage.getWidth(null), encodeImage.getHeight(null), null, 0, encodeImage.getWidth(null));
		int[] imageRGB = image.getRGB(0, 0, image.getWidth(null), image.getHeight(null), null, 0, image.getWidth(null));

		int encodeByteMask = (int)(Math.pow(2, encodeBits)) - 1 << (8 - encodeBits);
		int encodeMask = (encodeByteMask << 24) | (encodeByteMask << 16) | (encodeByteMask << 8) | encodeByteMask;

		int decodeByteMask = ~(encodeByteMask >>> (8 - encodeBits)) & 0xFF;
		int hostMask = (decodeByteMask << 24) | (decodeByteMask << 16) | (decodeByteMask << 8) | decodeByteMask;

		for (int i = 0; i < imageRGB.length; i++)
		{
			int encodeData = (encodeRGB[i] & encodeMask) >>> (8 - encodeBits);
			imageRGB[i] = (imageRGB[i] & hostMask) | (encodeData & ~hostMask);
		}

		image.setRGB(0, 0, image.getWidth(null), image.getHeight(null), imageRGB, 0, image.getWidth(null));
	}

	public Image getImage()
	{
		return image;
	}

	public Steganography(BufferedImage image)
	{
		this.image = image;
	}
}

import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;

import java.io.*;

import javax.imageio.ImageIO;

import javax.swing.*;

public class ImageHiding extends JFrame implements ActionListener
{
	BufferedImage hostImage;
	BufferedImage secretImage;

	JPanel controlPanel;
	JPanel imagePanel;

	JTextField encodeBitsText;
	JButton encodeBitsPlus;
	JButton encodeBitsMinus;

	JTextField nBitsText;
	JButton nBitsPlus;
	JButton nBitsMinus;

	ImageCanvas hostCanvas;
	ImageCanvas secretCanvas;

	Steganography s;

	public BufferedImage getHostImage()
	{
		BufferedImage img = null;

		try
		{
			img = ImageIO.read(new File("host_image.jpg"));
		}
		catch (IOException ioe) { ioe.printStackTrace(); }

		return img;
	}

	public BufferedImage getSecretImage()
	{
		BufferedImage img = null;

		try
		{
			img = ImageIO.read(new File("secret_image.jpg"));
		}
		catch (IOException ioe) { ioe.printStackTrace(); }

		return img;
	}

	public int getBits()
	{
		return Integer.parseInt(encodeBitsText.getText());
	}

	public void actionPerformed(ActionEvent event)
	{
		Object source = event.getSource();

		if (source == encodeBitsPlus)
		{
			int bits = this.getBits() + 1;

			if (bits > 8) { bits = 8; }

			encodeBitsText.setText(Integer.toString(bits));

			s = new Steganography(this.getHostImage());
			s.encode(this.getSecretImage(), bits);

			hostCanvas.setImage(s.getImage());
			hostCanvas.repaint();

			s = new Steganography(this.getSecretImage());
			s.getMaskedImage(bits);

			secretCanvas.setImage(s.getImage());
			secretCanvas.repaint();
		}
		else if (source == encodeBitsMinus)
		{
			int bits = this.getBits() - 1;

			if (bits < 0) { bits = 0; }

			encodeBitsText.setText(Integer.toString(bits));

			s = new Steganography(this.getHostImage());
			s.encode(this.getSecretImage(), bits);

			hostCanvas.setImage(s.getImage());
			hostCanvas.repaint();

			s = new Steganography(this.getSecretImage());
			s.getMaskedImage(bits);

			secretCanvas.setImage(s.getImage());
			secretCanvas.repaint();
		}
	}

	public ImageHiding()
	{
		GridBagLayout layout = new GridBagLayout();
		GridBagConstraints gbc = new GridBagConstraints();
		this.setTitle("Question 1");

		Container container = this.getContentPane();

		this.setLayout(layout);

		this.add(new JLabel("Bits to encode into host image:"));

		encodeBitsText = new JTextField("0", 5);
		encodeBitsText.setEditable(false);

		gbc.weightx = -1.0;
		layout.setConstraints(encodeBitsText, gbc);
		this.add(encodeBitsText);

		encodeBitsPlus = new JButton("+");
		encodeBitsPlus.addActionListener(this);

		encodeBitsMinus = new JButton("-");
		encodeBitsMinus.addActionListener(this);

		gbc.weightx = 1.0;
		layout.setConstraints(encodeBitsPlus, gbc);
		this.add(encodeBitsPlus);

		gbc.gridwidth = GridBagConstraints.REMAINDER;
		layout.setConstraints(encodeBitsMinus, gbc);
		this.add(encodeBitsMinus);

		GridBagLayout imageGridbag = new GridBagLayout();
		GridBagConstraints imageGBC = new GridBagConstraints();

		imagePanel = new JPanel();
		imagePanel.setLayout(imageGridbag);

		JLabel hostImageLabel = new JLabel("Host image:");
		JLabel secretImageLabel = new JLabel("Secret image:");

		imagePanel.add(hostImageLabel);

		imageGBC.gridwidth = GridBagConstraints.REMAINDER;
		imageGridbag.setConstraints(secretImageLabel, imageGBC);
		imagePanel.add(secretImageLabel);

		hostCanvas = new ImageCanvas(this.getHostImage());		
		secretCanvas = new ImageCanvas(this.getSecretImage());

		imagePanel.add(hostCanvas);
		imagePanel.add(secretCanvas);

		gbc.gridwidth = GridBagConstraints.REMAINDER;
		layout.setConstraints(imagePanel, gbc);
		this.add(imagePanel);

		Steganography host = new Steganography(this.getHostImage());
		host.encode(this.getSecretImage(), this.getBits());
		hostCanvas.setImage(host.getImage());

		Steganography secret = new Steganography(this.getSecretImage());
		secret.getMaskedImage(this.getBits());
		secretCanvas.setImage(secret.getImage());

		this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		this.pack();

		this.setVisible(true);
	}

	public static void main(String[] args)
	{
		ImageHiding frame = new ImageHiding();
		frame.setVisible(true);
	}

	public class ImageCanvas extends JPanel
	{	
		Image img;

		public void paintComponent(Graphics g)
		{
			g.drawImage(img, 0, 0, this);
		}

		public void setImage(Image img)
		{
			this.img = img;
		}

		public ImageCanvas(Image img)
		{
			this.img = img;

			this.setPreferredSize(new Dimension(img.getWidth(this), img.getHeight(this)));
		}
	}
}

class Steganography
{
	BufferedImage image;

	public void getMaskedImage(int bits)
	{
		int[] imageRGB = image.getRGB(0, 0, image.getWidth(null), image.getHeight(null), null, 0, image.getWidth(null));

		int maskBits = (int)(Math.pow(2, bits)) - 1 << (8 - bits);
		int mask = (maskBits << 24) | (maskBits << 16) | (maskBits << 8) | maskBits;

		for (int i = 0; i < imageRGB.length; i++)
		{
			imageRGB[i] = imageRGB[i] & mask;
		}

		image.setRGB(0, 0, image.getWidth(null), image.getHeight(null), imageRGB, 0, image.getWidth(null));
	}

	public void encode(BufferedImage encodeImage, int encodeBits)
	{
		int[] encodeRGB = encodeImage.getRGB(0, 0, encodeImage.getWidth(null), encodeImage.getHeight(null), null, 0, encodeImage.getWidth(null));
		int[] imageRGB = image.getRGB(0, 0, image.getWidth(null), image.getHeight(null), null, 0, image.getWidth(null));

		int encodeByteMask = (int)(Math.pow(2, encodeBits)) - 1 << (8 - encodeBits);
		int encodeMask = (encodeByteMask << 24) | (encodeByteMask << 16) | (encodeByteMask << 8) | encodeByteMask;

		int decodeByteMask = ~(encodeByteMask >>> (8 - encodeBits)) & 0xFF;
		int hostMask = (decodeByteMask << 24) | (decodeByteMask << 16) | (decodeByteMask << 8) | decodeByteMask;

		for (int i = 0; i < imageRGB.length; i++)
		{
			int encodeData = (encodeRGB[i] & encodeMask) >>> (8 - encodeBits);
			imageRGB[i] = (imageRGB[i] & hostMask) | (encodeData & ~hostMask);
		}

		image.setRGB(0, 0, image.getWidth(null), image.getHeight(null), imageRGB, 0, image.getWidth(null));
	}

	public Image getImage()
	{
		return image;
	}

	public Steganography(BufferedImage image)
	{
		this.image = image;
	}
}

import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;

import java.io.*;

import javax.imageio.ImageIO;

import javax.swing.*;

public class ImageHiding extends JFrame implements ActionListener
{
	BufferedImage hostImage;
	BufferedImage secretImage;

	JPanel controlPanel;
	JPanel imagePanel;

	JTextField encodeBitsText;
	JButton encodeBitsPlus;
	JButton encodeBitsMinus;

	JTextField nBitsText;
	JButton nBitsPlus;
	JButton nBitsMinus;

	ImageCanvas hostCanvas;
	ImageCanvas secretCanvas;

	Steganography s;

	public BufferedImage getHostImage()
	{
		BufferedImage img = null;

		try
		{
			img = ImageIO.read(new File("host_image.jpg"));
		}
		catch (IOException ioe) { ioe.printStackTrace(); }

		return img;
	}

	public BufferedImage getSecretImage()
	{
		BufferedImage img = null;

		try
		{
			img = ImageIO.read(new File("secret_image.jpg"));
		}
		catch (IOException ioe) { ioe.printStackTrace(); }

		return img;
	}

	public int getBits()
	{
		return Integer.parseInt(encodeBitsText.getText());
	}

	public void actionPerformed(ActionEvent event)
	{
		Object source = event.getSource();

		if (source == encodeBitsPlus)
		{
			int bits = this.getBits() + 1;

			if (bits > 8) { bits = 8; }

			encodeBitsText.setText(Integer.toString(bits));

			s = new Steganography(this.getHostImage());
			s.encode(this.getSecretImage(), bits);

			hostCanvas.setImage(s.getImage());
			hostCanvas.repaint();

			s = new Steganography(this.getSecretImage());
			s.getMaskedImage(bits);

			secretCanvas.setImage(s.getImage());
			secretCanvas.repaint();
		}
		else if (source == encodeBitsMinus)
		{
			int bits = this.getBits() - 1;

			if (bits < 0) { bits = 0; }

			encodeBitsText.setText(Integer.toString(bits));

			s = new Steganography(this.getHostImage());
			s.encode(this.getSecretImage(), bits);

			hostCanvas.setImage(s.getImage());
			hostCanvas.repaint();

			s = new Steganography(this.getSecretImage());
			s.getMaskedImage(bits);

			secretCanvas.setImage(s.getImage());
			secretCanvas.repaint();
		}
	}

	public ImageHiding()
	{
		GridBagLayout layout = new GridBagLayout();
		GridBagConstraints gbc = new GridBagConstraints();
		this.setTitle("Question 1");

		Container container = this.getContentPane();

		this.setLayout(layout);

		this.add(new JLabel("Bits to encode into host image:"));

		encodeBitsText = new JTextField("0", 5);
		encodeBitsText.setEditable(false);

		gbc.weightx = -1.0;
		layout.setConstraints(encodeBitsText, gbc);
		this.add(encodeBitsText);

		encodeBitsPlus = new JButton("+");
		encodeBitsPlus.addActionListener(this);

		encodeBitsMinus = new JButton("-");
		encodeBitsMinus.addActionListener(this);

		gbc.weightx = 1.0;
		layout.setConstraints(encodeBitsPlus, gbc);
		this.add(encodeBitsPlus);

		gbc.gridwidth = GridBagConstraints.REMAINDER;
		layout.setConstraints(encodeBitsMinus, gbc);
		this.add(encodeBitsMinus);

		GridBagLayout imageGridbag = new GridBagLayout();
		GridBagConstraints imageGBC = new GridBagConstraints();

		imagePanel = new JPanel();
		imagePanel.setLayout(imageGridbag);

		JLabel hostImageLabel = new JLabel("Host image:");
		JLabel secretImageLabel = new JLabel("Secret image:");

		imagePanel.add(hostImageLabel);

		imageGBC.gridwidth = GridBagConstraints.REMAINDER;
		imageGridbag.setConstraints(secretImageLabel, imageGBC);
		imagePanel.add(secretImageLabel);

		hostCanvas = new ImageCanvas(this.getHostImage());		
		secretCanvas = new ImageCanvas(this.getSecretImage());

		imagePanel.add(hostCanvas);
		imagePanel.add(secretCanvas);

		gbc.gridwidth = GridBagConstraints.REMAINDER;
		layout.setConstraints(imagePanel, gbc);
		this.add(imagePanel);

		Steganography host = new Steganography(this.getHostImage());
		host.encode(this.getSecretImage(), this.getBits());
		hostCanvas.setImage(host.getImage());

		Steganography secret = new Steganography(this.getSecretImage());
		secret.getMaskedImage(this.getBits());
		secretCanvas.setImage(secret.getImage());

		this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		this.pack();

		this.setVisible(true);
	}

	public static void main(String[] args)
	{
		ImageHiding frame = new ImageHiding();
		frame.setVisible(true);
	}

	public class ImageCanvas extends JPanel
	{	
		Image img;

		public void paintComponent(Graphics g)
		{
			g.drawImage(img, 0, 0, this);
		}

		public void setImage(Image img)
		{
			this.img = img;
		}

		public ImageCanvas(Image img)
		{
			this.img = img;

			this.setPreferredSize(new Dimension(img.getWidth(this), img.getHeight(this)));
		}
	}
}

class Steganography
{
	BufferedImage image;

	public void getMaskedImage(int bits)
	{
		int[] imageRGB = image.getRGB(0, 0, image.getWidth(null), image.getHeight(null), null, 0, image.getWidth(null));

		int maskBits = (int)(Math.pow(2, bits)) - 1 << (8 - bits);
		int mask = (maskBits << 24) | (maskBits << 16) | (maskBits << 8) | maskBits;

		for (int i = 0; i < imageRGB.length; i++)
		{
			imageRGB[i] = imageRGB[i] & mask;
		}

		image.setRGB(0, 0, image.getWidth(null), image.getHeight(null), imageRGB, 0, image.getWidth(null));
	}

	public void encode(BufferedImage encodeImage, int encodeBits)
	{
		int[] encodeRGB = encodeImage.getRGB(0, 0, encodeImage.getWidth(null), encodeImage.getHeight(null), null, 0, encodeImage.getWidth(null));
		int[] imageRGB = image.getRGB(0, 0, image.getWidth(null), image.getHeight(null), null, 0, image.getWidth(null));

		int encodeByteMask = (int)(Math.pow(2, encodeBits)) - 1 << (8 - encodeBits);
		int encodeMask = (encodeByteMask << 24) | (encodeByteMask << 16) | (encodeByteMask << 8) | encodeByteMask;

		int decodeByteMask = ~(encodeByteMask >>> (8 - encodeBits)) & 0xFF;
		int hostMask = (decodeByteMask << 24) | (decodeByteMask << 16) | (decodeByteMask << 8) | decodeByteMask;

		for (int i = 0; i < imageRGB.length; i++)
		{
			int encodeData = (encodeRGB[i] & encodeMask) >>> (8 - encodeBits);
			imageRGB[i] = (imageRGB[i] & hostMask) | (encodeData & ~hostMask);
		}

		image.setRGB(0, 0, image.getWidth(null), image.getHeight(null), imageRGB, 0, image.getWidth(null));
	}

	public Image getImage()
	{
		return image;
	}

	public Steganography(BufferedImage image)
	{
		this.image = image;
	}
}

import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;

import java.io.*;

import javax.imageio.ImageIO;

import javax.swing.*;

public class ImageHiding extends JFrame implements ActionListener
{
	BufferedImage hostImage;
	BufferedImage secretImage;

	JPanel controlPanel;
	JPanel imagePanel;

	JTextField encodeBitsText;
	JButton encodeBitsPlus;
	JButton encodeBitsMinus;

	JTextField nBitsText;
	JButton nBitsPlus;
	JButton nBitsMinus;

	ImageCanvas hostCanvas;
	ImageCanvas secretCanvas;

	Steganography s;

	public BufferedImage getHostImage()
	{
		BufferedImage img = null;

		try
		{
			img = ImageIO.read(new File("host_image.jpg"));
		}
		catch (IOException ioe) { ioe.printStackTrace(); }

		return img;
	}

	public BufferedImage getSecretImage()
	{
		BufferedImage img = null;

		try
		{
			img = ImageIO.read(new File("secret_image.jpg"));
		}
		catch (IOException ioe) { ioe.printStackTrace(); }

		return img;
	}

	public int getBits()
	{
		return Integer.parseInt(encodeBitsText.getText());
	}

	public void actionPerformed(ActionEvent event)
	{
		Object source = event.getSource();

		if (source == encodeBitsPlus)
		{
			int bits = this.getBits() + 1;

			if (bits > 8) { bits = 8; }

			encodeBitsText.setText(Integer.toString(bits));

			s = new Steganography(this.getHostImage());
			s.encode(this.getSecretImage(), bits);

			hostCanvas.setImage(s.getImage());
			hostCanvas.repaint();

			s = new Steganography(this.getSecretImage());
			s.getMaskedImage(bits);

			secretCanvas.setImage(s.getImage());
			secretCanvas.repaint();
		}
		else if (source == encodeBitsMinus)
		{
			int bits = this.getBits() - 1;

			if (bits < 0) { bits = 0; }

			encodeBitsText.setText(Integer.toString(bits));

			s = new Steganography(this.getHostImage());
			s.encode(this.getSecretImage(), bits);

			hostCanvas.setImage(s.getImage());
			hostCanvas.repaint();

			s = new Steganography(this.getSecretImage());
			s.getMaskedImage(bits);

			secretCanvas.setImage(s.getImage());
			secretCanvas.repaint();
		}
	}

	public ImageHiding()
	{
		GridBagLayout layout = new GridBagLayout();
		GridBagConstraints gbc = new GridBagConstraints();
		this.setTitle("Question 1");

		Container container = this.getContentPane();

		this.setLayout(layout);

		this.add(new JLabel("Bits to encode into host image:"));

		encodeBitsText = new JTextField("0", 5);
		encodeBitsText.setEditable(false);

		gbc.weightx = -1.0;
		layout.setConstraints(encodeBitsText, gbc);
		this.add(encodeBitsText);

		encodeBitsPlus = new JButton("+");
		encodeBitsPlus.addActionListener(this);

		encodeBitsMinus = new JButton("-");
		encodeBitsMinus.addActionListener(this);

		gbc.weightx = 1.0;
		layout.setConstraints(encodeBitsPlus, gbc);
		this.add(encodeBitsPlus);

		gbc.gridwidth = GridBagConstraints.REMAINDER;
		layout.setConstraints(encodeBitsMinus, gbc);
		this.add(encodeBitsMinus);

		GridBagLayout imageGridbag = new GridBagLayout();
		GridBagConstraints imageGBC = new GridBagConstraints();

		imagePanel = new JPanel();
		imagePanel.setLayout(imageGridbag);

		JLabel hostImageLabel = new JLabel("Host image:");
		JLabel secretImageLabel = new JLabel("Secret image:");

		imagePanel.add(hostImageLabel);

		imageGBC.gridwidth = GridBagConstraints.REMAINDER;
		imageGridbag.setConstraints(secretImageLabel, imageGBC);
		imagePanel.add(secretImageLabel);

		hostCanvas = new ImageCanvas(this.getHostImage());		
		secretCanvas = new ImageCanvas(this.getSecretImage());

		imagePanel.add(hostCanvas);
		imagePanel.add(secretCanvas);

		gbc.gridwidth = GridBagConstraints.REMAINDER;
		layout.setConstraints(imagePanel, gbc);
		this.add(imagePanel);

		Steganography host = new Steganography(this.getHostImage());
		host.encode(this.getSecretImage(), this.getBits());
		hostCanvas.setImage(host.getImage());

		Steganography secret = new Steganography(this.getSecretImage());
		secret.getMaskedImage(this.getBits());
		secretCanvas.setImage(secret.getImage());

		this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		this.pack();

		this.setVisible(true);
	}

	public static void main(String[] args)
	{
		ImageHiding frame = new ImageHiding();
		frame.setVisible(true);
	}

	public class ImageCanvas extends JPanel
	{	
		Image img;

		public void paintComponent(Graphics g)
		{
			g.drawImage(img, 0, 0, this);
		}

		public void setImage(Image img)
		{
			this.img = img;
		}

		public ImageCanvas(Image img)
		{
			this.img = img;

			this.setPreferredSize(new Dimension(img.getWidth(this), img.getHeight(this)));
		}
	}
}

class Steganography
{
	BufferedImage image;

	public void getMaskedImage(int bits)
	{
		int[] imageRGB = image.getRGB(0, 0, image.getWidth(null), image.getHeight(null), null, 0, image.getWidth(null));

		int maskBits = (int)(Math.pow(2, bits)) - 1 << (8 - bits);
		int mask = (maskBits << 24) | (maskBits << 16) | (maskBits << 8) | maskBits;

		for (int i = 0; i < imageRGB.length; i++)
		{
			imageRGB[i] = imageRGB[i] & mask;
		}

		image.setRGB(0, 0, image.getWidth(null), image.getHeight(null), imageRGB, 0, image.getWidth(null));
	}

	public void encode(BufferedImage encodeImage, int encodeBits)
	{
		int[] encodeRGB = encodeImage.getRGB(0, 0, encodeImage.getWidth(null), encodeImage.getHeight(null), null, 0, encodeImage.getWidth(null));
		int[] imageRGB = image.getRGB(0, 0, image.getWidth(null), image.getHeight(null), null, 0, image.getWidth(null));

		int encodeByteMask = (int)(Math.pow(2, encodeBits)) - 1 << (8 - encodeBits);
		int encodeMask = (encodeByteMask << 24) | (encodeByteMask << 16) | (encodeByteMask << 8) | encodeByteMask;

		int decodeByteMask = ~(encodeByteMask >>> (8 - encodeBits)) & 0xFF;
		int hostMask = (decodeByteMask << 24) | (decodeByteMask << 16) | (decodeByteMask << 8) | decodeByteMask;

		for (int i = 0; i < imageRGB.length; i++)
		{
			int encodeData = (encodeRGB[i] & encodeMask) >>> (8 - encodeBits);
			imageRGB[i] = (imageRGB[i] & hostMask) | (encodeData & ~hostMask);
		}

		image.setRGB(0, 0, image.getWidth(null), image.getHeight(null), imageRGB, 0, image.getWidth(null));
	}

	public Image getImage()
	{
		return image;
	}

	public Steganography(BufferedImage image)
	{
		this.image = image;
	}
}