// Contour Map Lookup Table

if (bitDepth==24) exit ("Cannot apply LUT to RGB image");
n = getNumber("Contour lines interval",20);
getLut(r,g,b);
for (i=0;i<r.length;i++) {
	if (i%n==0) {
		r[i] = 255;
		g[i] = 0;
		b[i] = 0;
	} else {
		r[i] = i;
		g[i] = i;
		b[i] = i;
	}
}
setLut(r,g,b);