An Unsupervised Two-Talker Speech Separation System Based on CASA

Abstract

On the basis of the theory about blind separation of monaural speech based on computational auditory scene analysis (CASA), a two-talker speech separation system combining CASA and speaker recognition was proposed to separate speech from other speech interferences in this paper. First, a tandem algorithm is used to organize voiced speech, then based on the clustering of gammatone frequency cepstral coefficients (GFCCs), an object function is established to recognize the speaker, and the best group is achieved through exhaustive search or beam search, so that voiced speech is organized sequentially. Second, unvoiced segments are generated by estimating onset/offset, and then unvoiced–voiced (U–V) segments and unvoiced–unvoiced (U–U) segments are separated respectively. The U–V segments are managed via the binary mask of the separated voiced speech, while the U–V segments are separated evenly. So far the unvoiced segments are separated. The simulation and performance evaluation verify the feasibility and effectiveness of the proposed algorithm.