import java.awt.image.BufferedImage;
import java.io.File;
import javax.imageio.ImageIO;
/** Column-jitter (stripe) amplitude inside a flat region of a rendered photo. */
public class StripeCheck {
    public static void main(String[] a) throws Exception {
        BufferedImage im = ImageIO.read(new File(a[0]));
        int x0 = Integer.parseInt(a[1]), y0 = Integer.parseInt(a[2]);
        int w = Integer.parseInt(a[3]), h = Integer.parseInt(a[4]);
        double[] col = new double[w];
        double lo = 255, hi = 0;
        for (int y = y0; y < y0 + h; y++)
            for (int x = x0; x < x0 + w; x++) {
                int c = im.getRGB(x, y);
                int l = (((c >> 16) & 0xFF) * 299 + ((c >> 8) & 0xFF) * 587 + (c & 0xFF) * 114) / 1000;
                col[x - x0] += l; if (l < lo) lo = l; if (l > hi) hi = l;
            }
        for (int i = 0; i < w; i++) col[i] /= h;
        double hf = 0; int n = 0;
        for (int i = 1; i < w - 1; i++) { hf += Math.abs(col[i] - (col[i-1] + col[i+1]) / 2); n++; }
        hf /= n;
        System.out.printf("%-28s region %dx%d  luma %.0f..%.0f (range %.0f)  colJitter=%.2f  = %.1f%% of local range%n",
                new File(a[0]).getName(), w, h, lo, hi, hi - lo, hf, 100 * hf / Math.max(1, hi - lo));
    }
}