Dominance Based Integration of Spatial and Spectral Features for Speech Enhancement

This paper proposes a versatile technique for integrating two conventional speech enhancement approaches, a spatial clustering approach (SCA) and a factorial model approach (FMA), which are based on two different features of signals, namely spatial and spectral features, respectively. When used separately the conventional approaches simply identify time frequency (TF) bins that are dominated by interference for speech enhancement. Integration of the two approaches makes identification more reliable, and allows us to estimate speech spectra more accurately even in highly nonstationary interference environments. This paper also proposes extensions of the FMA for further elaboration of the proposed technique, including one that uses spectral models based on mel-frequency cepstral coefficients and another to cope with mismatches, such as channel mismatches, between captured signals and the spectral models. Experiments using simulated and real recordings show that the proposed technique can effectively improve audible speech quality and the automatic speech recognition score.