Find the difference between two display using java.awt.Robot and Sikuli library

ScreenShotDifference

import java.awt.*;
import java.awt.image.BufferedImage;
import org.sikuli.script.*;
import javax.imageio.ImageIO;

import static controller.ImageController.isExist;
import static crfs.CP.contentEquals;

public class ScreenShotDifference {
    public static void main(String[] args) throws Exception {
        int white = new Color(255, 255, 255).getRGB();
        int black = new Color(0, 0, 0).getRGB();

        Screen s = new Screen();

        try {
            Robot robot = new Robot();
            Rectangle area = new Rectangle(Toolkit.getDefaultToolkit().getScreenSize());

            long start = System.nanoTime();
            BufferedImage bufferedImage1 = robot.createScreenCapture(area);
            System.out.println("First image taken");
            s.wait(3.);
            System.out.println("Start take the second image");
            BufferedImage bufferedImage2 = robot.createScreenCapture(area);
            BufferedImage diff = bufferedImage1;

            for (int i=0; i<bufferedImage1.getWidth(); i++) {
                for (int j=0; j<bufferedImage1.getHeight(); j++) {
                    if (bufferedImage1.getRGB(i, j) == bufferedImage2.getRGB(i, j)) {
                        diff.setRGB(i, j, black);
                    } else {
                        diff.setRGB(i, j, white);
                    }
                }
            }

            ImageIO.write(diff, "png", new File("/Users/arwankhoiruddin/Desktop/diff.png"));

        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}