import java.awt.image.BufferedImage;
import java.awt.image.Raster;
public class Main {
public static void main(String[] argv) throws Exception {
}
public static double meanValue(BufferedImage image) {
Raster raster = image.getRaster();
double sum = 0.0;
for (int y = 0; y < image.getHeight(); ++y){
for (int x = 0; x < image.getWidth(); ++x){
sum += raster.getSample(x, y, 0);
}
}
return sum / (image.getWidth() * image.getHeight());
}
}