title: how to get percentage of similarity using libfacerec Opencv library
body: <p>It might be an easy question but i am bit confuse so hope some one guide me properly.</p>
  
  <p>i am using face recognition library of openCV libfacerec , it gives good result but i need to estimate the percentage of similarity. If i use unknown image as an input then still it predict as if the person exist in the system on the basis of last distance value </p>
  
  <pre><code>         if(dist &lt; minDist) {
          minDist = dist;
          minClass = _labels[sampleIdx];
      }
  </code></pre>
  
  <p>I need to define some threshold and then validate/invalidate the user picture based on that threshold against some percentage or distance value, does any one know how to do that using libfacerec library because in this library there is no public variable to see distance or percentage value? Otherwise do i need to code inside the library for it because as far as i understand it does not contain this feature??? </p>