title: A constrained sequential EM algorithm for speech enhancement.
abstract: Speech enhancement is a fundamental problem, the goal of which is to estimate clean speech s(t), given a noise-contaminated signal s(t)+n(t), where n(t) is white or colored noise. This task can be viewed as a probabilistic inference problem which involves estimating the posterior distribution of hidden clean speech, given a noisy observation. Kalman filter is a representative method but is restricted to Gaussian distributions only. We consider the generalized auto-regressive (GAR) model in order to capture the non-Gaussian characteristics of speech. Then we present a constrained sequential EM algorithm where Rao-Blackwellized particle filters (RBPFs) are used in the E-step and model parameters are updated in a sequential manner in the M-step under positivity constraints for noise variance parameters. Numerical experiments confirm the high performance of our proposed method, compared to Kalman filter-based methods, in the task of sequential speech enhancement.
authors.affiliation: Department of Computer Science, Pohang University of Science and Technology, San 31 Hyoja-dong, Nam-gu, Pohang 790-784, Republic of Korea.
authors.forename: Sunho
authors.initials: S
authors.lastname: Park
authors.forename: Seungjin
authors.initials: S
authors.lastname: Choi
mesh_terms: D000465:Algorithms; D003143:Communication Devices for People with Disabilities; D015233:Models, Statistical; D009622:Noise; D016011:Normal Distribution; D012044:Regression Analysis