import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.*;

import javax.imageio.ImageIO;
import javax.swing.*;

public class Gray extends JFrame {

	BufferedImage image;



	public Gray() throws IOException
	{
		File input = new File("v8.jpg");
		 image = ImageIO.read(input);

		 int h = image.getHeight();
		  int w = image.getWidth();

		for (int i = 0; i < h; i++)
		{
		  for (int j = 0; j < w; j++)
		  {
			  int pixel = image.getRGB(i, j);


			  int alpha = (pixel >> 24) & 0xff;
			    int red = (pixel >> 16) & 0xff;
			    int green = (pixel >> 8) & 0xff;
			    int blue = (pixel) & 0xff;
			    int rgb=(red+green+blue)/3;

			    image.setRGB(i, j, rgb);

			  }
		  }

	this.setTitle("Zaliczenie");
	this.setSize(500,500);
	this.setLocationRelativeTo(null);
	this.setResizable(true);
	}

	public void paint(Graphics g) {
		  g.drawImage( image, 0, 0, null);
		  }

	public static void main (String [] args) throws IOException
	{
		Gray progr = new Gray();
		progr.setVisible(true);
	}

}