title: Python edge detection and curvature calculation
body: <p>I know the edge detection problem has been posted before (in Java: <a href="https://stackoverflow.com/questions/2952165/count-the-number-of-objects-in-an-image">Count the number of objects in an Image</a>, language independent: <a href="https://stackoverflow.com/questions/3540910/image-edge-detection">Image edge detection</a>), but I want to know how to implement it in python.</p>
  
  <p>I'm doing edge detection and curvature calculation around the edge on some simple shapes (binary shape with some noise). I know there are some wrapper for OpenCV, but not sure which one is better: pyopencv, pycv, pycvf?</p>
  
  <p>Since I'm basically only doing this two tasks, I'm also not sure whether it would be faster to implement it by myself rather than using the library.</p>