On the importance of components of the modulation spectrum for speaker verification
Sarel van Vuuren, Hynek Heřmanský · 1998
We provide an analysis of the relative importance of components of the modulation spectrum for speaker verification. The aim is to remove less relevant components and reduce system sensitivity to acoustic disturbances while improving verification accuracy. Spectral components between 0.1 Hz and 10 Hz are found to contain the most useful speaker information. We discuss this result in the context of RASTA processing and cepstral mean subtraction. When compared to cepstral mean subtraction that retains components up to 50 Hz, lowpass filtering to 10 Hz with downsampling by 75% is found to significantly improve robustness in mismatched conditions. The downsampling results in a large computational savings. 1. INTRODUCTION Many speaker verification systems attempt to characterize a speaker using acoustic features based on filtered logarithmic spectral energies derived from a short-time analysis [1, 5, 2]. Spectral components of the time sequences of logarithmic spectral energies, aka. the ...