legend11_h.m

matlab - image processing - histogram equalization

% legend11 - Histogram Equalization
clear;
x=imread('pout.tif');
[a b]=size(x);
v=zeros(1,256);
    for i=1:a;
        for j=1:b;
            for n=0:255;
                if x(i,j)==n;
                    v(1,n+1)=v(1,n+1)+1;
                end
            end
        end
    end
c=zeros(1,256);    
d=255/(291*240);
c(1,1)=d*v(1,1);
    for h=2:256;
        c(1,h)=c(1,h-1)+(d*v(1,h));
    end
    for i=1:a;
        for j=1:b;
            g(i,j)=c(1,x(i,j));
            k(i,j)=round(g(i,j));
        end
    end
p=zeros(1,256);    
    for i=1:a;
        for j=1:b;
            for n=0:255;
                if k(i,j)==n;
                   p(1,n+1)=p(1,n+1)+1;
                end
            end
        end
    end
figure,imagesc(g);
figure,plot(p);