> You basically want to throw some edge detection at it, and then look for anything that seem like corners.
Which, if you're a web dev like I am, seems scary at first, especially when you're (like me) lacking a CS education. However, as it turns out, understanding edge detection and Haar cascades (for feature detection, that was the problem I was solving) enough to be dangerous with OpenCV is surprisingly easy! I recently built some facial feature detection stuff in it that is in production right now, and it only took me a couple weeks :) So, have a play!
Which, if you're a web dev like I am, seems scary at first, especially when you're (like me) lacking a CS education. However, as it turns out, understanding edge detection and Haar cascades (for feature detection, that was the problem I was solving) enough to be dangerous with OpenCV is surprisingly easy! I recently built some facial feature detection stuff in it that is in production right now, and it only took me a couple weeks :) So, have a play!