Implement a Matlab function that produces the normalized correlation at each pixel.

function norm_cor = CV_norm_cor(I,f,k)
%
% CV_norm_cor - normalized correlation image
% On input:
%     I (mxn array): input image
%     f (2k+1 x 2k+1 array): kernel array
%     k (int): size of window (2k+1 by 2k+1 window)
% On output:
%     norm_cor (mxn array): normalized correlation at each pixel
% Call:
%     Inc = CV_norm_cor(I,[1 0 1; 1 0 1; 1 0 1],1);    % does a 3x3 window
% Method:
%     See Forsyth and Ponce, Chapter 7
% Author:
%     Your name
%     UU
%     Fall 2012
%