clear all
clc
close all
A=imread('./images/wdg4.gif');

subplot(2,2,1)
imshow(A,[0,255])

H_A = imhist(A);
subplot(2,2,2)
bar(H_A)

PROG = 40;
B=A;
[a,b]=size(B);
pole=0;
for i=1:a
    for j=1:b
        if B(i,j) <= PROG
            B(i,j)=1;
            pole = pole + 1;
        else
            B(i,j)=0;
        end
    end
end
subplot(2,2,3)
imshow(B,[0,1]);
pole/(a*b)
pole