title: Detecting how blurred an image is
body: <p>I want to detect how blurred an image is, may be It can be called "blur extend".
  I found a useful paper for this:</p>
  
  <p><a href="http://www.cs.cmu.edu/~htong/pdf/ICME04_tong.pdf" rel="nofollow noreferrer">http://www.cs.cmu.edu/~htong/pdf/ICME04_tong.pdf</a></p>
  
  <p>I used OpenCV and implemented all steps from this paper, but the result is not same as result from this paper.</p>
  
  <p>Can someone give me any advise for detecting "blur extend"?</p>