Java and haarcascade face and mouth detection - mouth as the nose

Question

Today I begin to test the project which detects a smile in Java and OpenCv. To recognition face and mouth project used haarcascade_frontalface_alt and haarcascade_mcs_mouth But

Answer 1

Most likely it detects it wrong on your picture, because of proportion of face (too long distance from eyes to mouth compared to distance between eyes). Detection of mouth and nose using haar detector isn't very stable, so algorithms usually use geometry model of face, to choose best combination of feature candidates for each facial feature. Some implementations can even try to predict mouth position based on eyes, if no mouth candidates was found.

Haar detector isn't the newest and best known at this time for feature detection. Try to use deformable parts model implementations. Try this, they have matlab code with efficient c++ optimized functions: https://www.ics.uci.edu/~xzhu/face/