Novel Cochlear Filter Based Cepstral Coefficients for Classification of Unvoiced Fricatives

Abstract

In this paper, the use of new auditory-based features derived from cochlear filters, have been proposed for classification of unvoiced fricatives. Classification attempts have been made to classify sibilant (i.e., /s/, /sh/) vs. non-sibilants (i.e., /f/, /th/) as well as for fricatives within each sub-category (i.e., intra-sibilants and intra-non-sibilants). Our experimental results indicate that proposed feature set, viz., Cochlear Filterbased Cepstral Coefficients (CFCC) performs better for individual fricative classification (i.e., a jump of 3.41 % in average classification accuracy and a fall of 6.59 % in EER) in clean conditions than the stateof-the-art feature set, viz., Mel Frequency Cepstral Coefficients (MFCC). Furthermore, under signal degradation conditions (i.e., by additive white noise) classification accuracy using proposed feature set drops much slowly (i.e., from 86.73 % in clean conditions to 77.46 % at SNR of 5 dB) than by using MFCC (i.e., from 82.18 % in clean conditions to 46.93 % at SNR of 5 dB).