title: Opencv C - Cartesian to Polar image transformation
body: <p>Hi i want to transform a image like this (right to left image ):
  <img src="https://i.stack.imgur.com/foLNn.jpg" alt="enter image description here"></p>
  
  <p>I have searching about functions like cvCartToPolar but i dont know how to use it..</p>
  
  <p>Can someone help me? :)</p>