% fig2_41.m
% STD as a meaure of intensity contrast

I = imread('Fig0241(a)(einstein low contrast).tif');
I_1d = reshape(I, 1, 679*800);
imhist(I);
std(double(I_1d))

I = imread('Fig0241(a)(einstein med contrast).tif');
I = imread('Fig0241(a)(einstein hig contrast).tif');