Gaussian process regression for voice activity detection and speech enhancement

Gaussian process (GP) model is a flexible nonparametric Bayesian method that is widely used in regression and classification. In this paper we present a probabilistic method where we solve voice activity detection (VAD) and speech enhancement in a single framework of GP regression, modeling clean speech by a GP smoother. Optimized hyperparameters in GP models lead us to a novel VAD method since learned length-scale parameters in covariance functions are much different between voiced and unvoiced frames. Clean speech is estimated by posterior means in GP models. Numerical experiments confirm the validity of our method.