Reliable acoustic-phonetic (AP) information derived from the speech signal can be used to detect and correct errors in the output of a phone recognizer. In this paper, limited acoustic-phonetic information derived primarily by processing the excitation source information in the speech signal is used to improve the performance of detection of manner of articulation from a baseline phone recognition system. A context-independent HMM-based monophone system without any language information is used as the baseline system for this purpose. The performance of the phone recognizer in terms of its ability to detect the manners of articulation is studied. The errors in the hypothesis of the manner of articulation of phones are corrected using AP information such as voicing, voice bar and frication. It is shown that significant improvement can be achieved by using simple or limited AP information.
N. Dhananjaya, B. Yegnanarayana, Suryakanth V. Gan