Sun-Yuan Kung, Speaker Verification from Coded Telephone Speech Using Stochastic Feature Transformation and Handset Identification

A handset compensation technique for speaker verification from coded telephone speech is proposed. The proposed technique combines handset selectors with stochastic feature transformation to reduce the acoustic mismatch between different handsets and different speech coders. Coder-dependent GMM-based handset selectors are trained to identify the most likely handset used by the claimants. Stochastic feature transformations are then applied to remove the acoustic distortion introduced by the coder and the handset. Experimental results show that the proposed technique outperforms the CMS approach and significantly reduces the error rates under six different coders with bit rates ranging from 2.4 kb/s to 64 kb/s. Strong correlation between speech quality and verification performance is also observed.