Why is my dilation not working when N is greater than 1?

I have been working on the dilation problem, but I cannot see why the dilation only works for when N= 1.

function [img_out] = myDilation(img_in, N)

M=size(img_in);

for k= 0:N

      for i = 1:M(1)

          for j = 1:M(2)

                  if (i+k)<= M(1)

                      if img_in(i+k,j,1:3)==0

                          img_out(i,j,1:3)=0;

                      end

                  end

                  if (i-k)>0

                      if img_in(i-k,j,1:3)==0

                          img_out(i,j,1:3)=0;

                      end

                  end

                  if (j+k)<= M(2)

                      if img_in(i,j+k,1:3)==0  

                          img_out(i,j,1:3)= 0;

                      end

                  end

                  if (j-k)>0

                      if img_in(i,j-k,1:3)==0    

                          img_out(i,j,1:3)= 0;

                      end

                  end

                  if (i+k)<= M(1) && (j+k)<= M(2)

                      if img_in(i+k,j+k,1:3)==0 

                          img_out(i,j,1:3)= 0;

                      end

                  end

                  if (i+k)<= M(1) && (j-k)>0

                      if img_in(i+k,j-k,1:3)==0 

                          img_out(i,j,1:3)= 0;

                      end

                  end

                  if (i-k)>0 && (j+k)<= M(2)

                      if img_in(i-k,j+k,1:3)==0  

                          img_out(i,j,1:3)= 0;

                      end

                  end

                  if (i-k)>0 && (j-k)>0

                      if img_in(i-k,j-k,1:3)==0  

                          img_out(i,j,1:3)= 0;

                      end

                  end

                  if img_in(i,j,1:3)==1

                      img_out(i,j,1:3) = 1;

                  end
          end
      end
  end
  end

[Walter Roberson]

What do you observe when you attempt to use a different N ?

Answer 1

[Image Analyst]

Christopher, did you not learn anything when I rewrote your erosion code for you? This dilation code is the same mess that you had for erosion. A dilation is a local max, so program it up that way. Just abandon that whole approach above, which is wrong, and do the much shorter, simpler, and correct way I showed you in the erosion example.