Index problem help

Hello Experts,

I am trying to build the median filter with given window size. Here is what I did so far, please correct me because for some reason I don't get the right results for general rows and cols (non equal or equal):

function [ newImg ] = myMedian( img, rows, cols )

ModifyImg = padarray(img,[(abs(rows-cols)+1) (abs(rows-cols)+1)]);

newImg = zeros(size(img));

for i = 1:(size(ModifyImg,1) - 2*(abs(rows-cols)+1))
    for j = 1:(size(ModifyImg,2) - 2*(abs(rows-cols)+1))

          window = ModifyImg(i:i+rows-1, j:j+cols-1);
          Sorted_Window = sort(window(:));
          newImg(i,j) = Sorted_Window(ceil(0.5*rows*cols));

      end
  end

[Jan]

Please explain, why you assume, that you do not get the correct results.