GestureRecognitionToolkit  Version: 0.2.0
The Gesture Recognition Toolkit (GRT) is a cross-platform, open-source, c++ machine learning library for real-time gesture recognition.
ClassificationModulesExamples/GMMExample/GMMExample.cpp
Note
The GMM algorithm can fail to train on some occasions, if this happens just try and run the training algorithm again and it should eventially converge.