title: How to find best closed contour from set of points in numpy array
body: <p>I have the following image Points on the contour of chamber</p>
  
  <p><img src="https://i.stack.imgur.com/ebhxV.png" alt=""></p>
  
  <p>To detect the shape of chamber applied <code>approxPolyDP</code> and the result is as follows.</p>
  
  <p>after approxPolyDP</p>
  
  <p><img src="https://i.stack.imgur.com/Q5gvb.png" alt=""></p>
  
  <p>Is there any other method which I can use to detect the closed shape of chamber?</p>