title: different results using imfilter and conv2
body: <p>Based on <a href="https://stackoverflow.com/questions/10672184/implementing-imfilter-in-matlab">this question</a> and <a href="https://stackoverflow.com/questions/7909466/differences-between-imfilter-and-conv2-matlab">this one</a> I thought that "imfilter" and "conv2" should have the same results. But try this code you will see the differences. What is the problem?  </p>
  
  <pre><code>I = imread('tire.tif');  
  fil=[1 2 3;4 5 6;7 8 9];  
  out1=conv2(double(I),fil,'same');  
  out2=uint8(out1);  
  out3=imfilter(I,fil,'same');
  </code></pre>