Image comparison | To compare two images given their URL

Imgcmp

//SIMPLE PROGRAM CREATED BY TEAM BLOX AS PART OF STARTUP BOX PROGRAM
//USER CAN GIVE TWO IMAGE URLS AND THE PROGRAM COMPARES RGB VALUES OF PIXELS AND RETURNS THE SIMILARITY ON A SCALE OF 0-100
//ANY QUERIES CONTACT: shaheenkader@outlook.com
//                   : syameradi@gmail.com
//                   : afrahnv@gmail.com

package imager;

import java.awt.image.BufferedImage;
import javax.imageio.ImageIO;
import java.io.IOException;
import java.net.URL;
public class Imagecompare
{
	public static void main(String args[])
	  {
		String s1;
	    BufferedImage img1 = null;
	    BufferedImage img2 = null;
	    try {
	      URL url1 = new URL("http://www.lac.inpe.br/JIPCookbook/Resources/ImageSimilarity/d02.jpg");
	      URL url2 = new URL("http://www.lac.inpe.br/JIPCookbook/Resources/ImageSimilarity/s02.jpg");
	      img1 = ImageIO.read(url1);
	      img2 = ImageIO.read(url2);
	    } catch (IOException e) {
	      e.printStackTrace();
	    }
	    int width1 = img1.getWidth(null);
	    int width2 = img2.getWidth(null);
	    int height1 = img1.getHeight(null);
	    int height2 = img2.getHeight(null);
	    if ((width1 != width2) || (height1 != height2)) {
	      System.err.println("Error: Images dimensions mismatch");
	      System.exit(1);
	    }
	    long diff = 0;
	    for (int y = 0; y < height1; y++) {
	      for (int x = 0; x < width1; x++) {
	        int rgb1 = img1.getRGB(x, y);
	        int rgb2 = img2.getRGB(x, y);
	        int r1 = (rgb1 >> 16) & 0xff;
	        int g1 = (rgb1 >>  8) & 0xff;
	        int b1 = (rgb1      ) & 0xff;
	        int r2 = (rgb2 >> 16) & 0xff;
	        int g2 = (rgb2 >>  8) & 0xff;
	        int b2 = (rgb2      ) & 0xff;
	        diff += Math.abs(r1 - r2);
	        diff += Math.abs(g1 - g2);
	        diff += Math.abs(b1 - b2);
	      }
	    }
	    double n = width1 * height1 * 3;
	    double p = diff / n / 255.0;
	    double percnt = 100.0-(p*100.0);
	    System.out.println("PERCENT: " +percnt);
	  }
	
}