compare two picture(images)
<blockquote>
  <p><strong>Possible Duplicate:</strong><br>
  <a href="http://stackoverflow.com/questions/23931/what-algorithm-to-compare-two-images">What algorithm to compare two images</a>  </p>
</blockquote>



<p>what is algorithm to compare two picture?
after filtration tow picture, how do compare?
in image processing?
Compared pixel after pixel?</p>
