%generate test image ZONE

t=linspace(0,511,512);
Z=[];
for I=1:512
   for J=1:512
      d=sqrt(t(I)^2+t(J)^2);
      Z(I,J)=floor((sin(d*(d^2/5000000+d/1000+.0002))+1)*128);
   end
end

figure;
imshow(uint8(Z));