Paper: Signal Processing For Robust Speech Recognition

ACL ID H94-1066
Title Signal Processing For Robust Speech Recognition
Venue Human Language Technologies
Session Main Conference
Year 1994

This paper describes a series of ceps~al-based compensation pro- cedures that render the SPHINX-II system more robust with respect to acoustical environment. The first algorithm, phone- dependent cepstral compensation, is similar in concept to the pre- viously-described MFCDCN method, except that cepstral com- pensation vectors are selected according to the current phonetic hypothesis, rather than on the basis of SNR or VQ codeword iden- tity. We also describe two procedures to accomplish adaptation of the VQ codebook for new environments, as well as the use of reduced-bandwidth f~equency analysis to process telephone-band- width speech. Use of the various compensation algorithms in con- sort produces a reduction of error rates for SPHINX-II by as much as 40 percent relative to the rate ac...