Feature/Keypoints detection is a very interesting and useful tool to have around when doing image processing,  it has endless applications from tracking objects, matching and searching images to more advanced stuff...So far I've been using SURF for this, but other than being complicated and very resource consuming, the algorithm itself is patented in the US and cannot be used for commercial stuff without a license, in addition to that, the only implementation I could find (libopensurf) is GPL'd..

So I removed all SURF code from the repo and I'm using this relatively new super fast/lightweight algorithm, called FREAK....Note that FREAK is a keypoint descriptor, so it needs something to find keypoints first, for this I'm using a corner detection algorithm called FAST.

To give you an idea of what you can do with this FAST/FREAK detector, I made this short video: