How do I get rid of the blue screen while dilating an image?

Not being allowed to use imdilate for my code, I got no error when I ran my code to dilate the image, however it came up as a blue screen instead of the dilated image. Can anyone help me figure out where the problem is? Thanks

function [img_out] = myDilation(img_in, N)

[m,n]=size(img_in);

img_out= zeros(m,n);

   for i=1:m

       for j=1:n

            if (img_in(i,j)==1)

                for k=1:N

       for l=1:N

           if(img_in(k,l)==1)

           c=i+k;

           d=j+l;

           img_out(c,d)=1;

           end

       end

                end

            end

       end

   end

end

Answer 1

[Image Analyst]

You must need to think about what you are doing, that's all. And you'll realize your obvious mistake. The dilation is a local max. You're not doing that at all. Your code is wrong in more than 1 way. For one thing you don't check only on the central pixel, you check for any pixel in the window. Secondly you're not even scanning an NxN window around i,j You need to do

for k = -N : N
  for l = -N : N
     if(img_in(i + k, j + l) == 1)
         img_out(i, j)=1;
         break;

Next, this is a double image, not an RGB image, so how did you get blue? Try to just display it like

imshow(img_out, []);