title: Estimate 2D transformation between two sets of points using RANSAC
body: <p>As I know, OpenCV uses RANSAC in order to solve the problem of <code>findHomography</code> and it returns some useful parameters like the <code>homograph_mask</code>. </p>
  
  <p>However, if I want to estimate just 2D transformation which means an Affine Matrix, is there a way to use the same methodology of <code>findHomography</code> which uses RANSAC and return that mask ?</p>