Root-power sums and spectral slope distortion measures for all-pole models of speech
Brian A. Hanson, Hynek Heřmanský, Hisashi Wakita · The Journal of the Acoustical Society of America · 1985
Distortion measures for use in speech processing are presented with emphasis on improvement of efficiency and recognition performance for noisy speech. Good results have been obtained from measures calculated from differences of root-power sums (i.e., differences of index-weighted cepstral coefficients: k *ck). This type of distortion measure can be derived as an approximation to the spectral slope distortion measure, which expresses slope differences between test and reference logarithmic spectra. However, when used on all-pole model spectra, the root-power sum distortion is computationally more efficient. It is well-suited for use with both linear predictive (LP) analysis and the recently proposed perceptually based LP [H. Hermansky, B. A. Hanson, and H. Wakita, IEEE Proc. ICASSP 85, 509–512 (1985)]. The proposed distortion measures are shown to provide equal or better recognition scores compared to standard LP-cepstral matching in low noise conditions and substantial improvements in noisy conditions.