title: How to detect parallelograms from the detected edge points in python
body: <p>I am reading an image and trying to detect parallelogram in the image. I have created an array which contains edge points(local peaks) using Hough Transform
  (p = x<em>cos(theta) + y</em>sin(theta)). I got around 2300 edge points(X,Y) and I am not sure how to get/extract parallelogram from it. Out of 2300 edge points, some of the edge points are of circular shape, the triangular shape including parallelogram.</p>
  
  <p>If I start considering edge-points(X,Y) as it is then it will not work as they are not only vertices of parallelogram and edge points are in big number(2300 points). </p>
  
  <p>[EDIT1]</p>
  
  <p>I have stored the edge point in <strong>test_img</strong> and it contains the pixel value.
  test_img[point.getX(), point.getY()] = 255</p>
  
  <p>test_img.size = 2343</p>
  
  <p>After plotting above test_image "plt.imshow(test_img, cmap="gray")" I am getting image as below</p>
  
  <p>Any help would be highly appreciated.</p>
  
  <p><a href="https://i.stack.imgur.com/D5Rd2.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/D5Rd2.jpg" alt="enter image description here"></a></p>