title: Find Exact Matches of SURF in openCV
body: <p>I am using openCV Surf tracker to find exact points in two images.
  as you know, Surf returns many Feature points in both images. what i want to do is using these feature parameters to find out which matches are exactly correct (true positive matches). In my application i need only true positive matches.</p>
  
  <p>These parameters existed : <em>Hessian</em>, <em>Laplacian</em>, <em>Distance</em>, <em>Size</em>, <em>Dir</em>.</p>
  
  <p>I dont know how to use these parameters?
  is exact matches have less distance or more hessian? laplacian can help ? size or dir can help ?</p>
  
  <p>How can i find Exact matches(true positives)??</p>