Real-time speech enhancement in noisy reverberant multi-talker environments based on a location-independent room acoustics model

This paper describes a new real-time speech enhancement method that reduces signal distortion caused by stationary noise and late reflections of reverberation in speech signals captured by a single distant microphone under multi-talker conditions. A major problem here is how to estimate the energy of the late reflections in real time when the room impulse responses from individual talkers to the microphone are not given or fixed in advance. To solve this problem, we introduce a probabilistic room acoustics model, and provide a method for estimating the energy of late reflections based on this model. In this method, parameters of the model for a room can be fixed in advance only from a few seconds of observation. By incorporating the proposed approach into a conventional frequency domain noise reduction scheme, we realize an integrated real-time speech enhancement framework. The effectiveness of the proposed method is confirmed experimentally for a case where there are two talkers in a room.