Adding a Brightness Value

Can someone help me in writing a code that brightens the top left corner of an image by y, where y is an integer variable representing the amount by which to increase brightness. I'm still in the basics, so I need to use for loops or vectorization, no brightness function. Just writing out an actual code that can manipulate the sizes and layers.

I know that I will be using something along the lines of i= 1:row/2: end and j= 1: col/2: end... or at least I think so?

Thanks!

Answer 1

[KSSV]

I = imread('your image') ;
y = 100 ;  % add pixel value 
I(1,1,:) = I(1,1,:)+y;   % top left corner is given by (1,1)