title: Compare two faces (and their likeness)
body: <p>Is there is a way to compare two faces (perhaps with <a href="http://en.wikipedia.org/wiki/OpenCV" rel="noreferrer">OpenCv</a>) and get a score of their likeness? I mean to apply a facial recognition algorithm, but <strong>only between 2 faces</strong>, not on an entire dataset.</p>
  
  <p>The problem is that, for example, <a href="http://en.wikipedia.org/wiki/Eigenface" rel="noreferrer">Eigenfaces</a> requires at least 2 training images.</p>