title: Opencv: How to Fit an Image into Non-Rectangular Contour?
body: <p>I want to fit an image of a clown like face into a contour of another face (a person).
  I am detecting the persons face and getting a elliptical-like contour. 
  I can figure out the center, radius, highest, lowest, left-most and right-most points.</p>
  
  <p>How do I fit the clown face (a square image which I can make elliptical by cutting the face out of the empty background of a png and then detecting the contour) into the persons face?</p>
  
  <p>Or at the least, how do I fit a polygon into another polygon.</p>
  
  <p>I can fit a rectangular image into a rectangular contour with ease, but faces aren't that shape.</p>
  
  <p>Python preferable, but C++ is also manageable, thank you.</p>
  
  <p>Edit: Visual representation as requested:</p>
  
  <p>I have </p>
  
  <p><img src="https://i.stack.imgur.com/80Uxi.png" alt=""></p>
  
  <p>and I want to make it like this: </p>
  
  <p><img src="https://i.stack.imgur.com/b0fZn.jpg" alt=""></p>
  
  <p>but I want the clown face to stretch over the guys face and fit within the blue contour.</p>