Your program is really a good idea. Just tried it with FLStudio and a Minimoog-like Vsti,really cool. But the main problem is that it is difficult to get an accurate result. Sometime the algorithm catches some points in the background, sometime not, sometime my hand, sometime not. It is not really "musically" usable. We should have the possibility to define more parameters than only the treshold value (more parameters, possibility to chose another OpenCV algorithm,etc...) to improve the follow-up of the points .
Keep the good work guy !