We have to say, [Murtaza]’s example game in his newest video isn’t very exciting. However, the OpenCV technique he uses to track a hand and identify its distance from a single video camera is pretty interesting. The demo shows a random button on the screen and you have to use your hand to press the button which then moves so you can try again. The hand measurement seems accurate to a few centimeters which is good enough for numerous applications.

The Python code is actually quite straightforward. Essentially, the software tracks your hand and by estimating its relative size to identify how far away it is. Of course, your hand might also rotate, and [Murtaza] works through all the cases step-by-step. If we wanted to know a distance, we’d probably turn to ultrasonics or a time of flight sensor. The problem is, those sensors can’t tell your hand from anything else that happens to be in front of it. The use of a single video camera to track and locate is pretty impressive.

If you haven’t used OpenCV before, the channel has a lot of tutorials and they are all worth watching. computer vision is a terrific technique and can replace a lot of things in some applications. GPS, for example. Or, try this creepier tracking application next Halloween.