Question about color histogram

Dear Sir/Ma'am

I implement the Color Histogram code for an image here is code what i want to implement

t1=imread('111.jpg');

t1r=t1(:,:,1);

t1g=t1(:,:,2);

t1b=t1(:,:,3);

figure;

subplot(221);imhist(t1r);title('Red Plane');

subplot(222);imhist(t1g);title('Green Plane');

subplot(223);imhist(t1b);title('Blue Plane');

subplot(224);imshow(t1);title('original image');

now i want to compute the probability histogram as follows

p(ri)=(Number of pixels in ri)/(width*height)

where p(ri) represents the relative frequency

Answer 1

[Walter Roberson]

subplot(221); ri = imhist(t1r); title('Red Plane');
p = ri ./ numel(t1r);

[Piyush Kothyari]

thank you sir