Mimic Resistance of Speaker Verification Using Phoneme Spectra

Abstract

The susceptibility to mimicry of the speaker-verification technique discussed in the paper “Automatic Speaker Verification Using Phoneme Spectra” was evaluated with the assistance of a professional performer specializing in impersonations. Subjects to be mimicked were six speakers selected from the previously recorded population. After becoming familiar with each speaker, the impersonator was permitted to mimic the speaker immediately after his utterance of each selected word. The subjects' utterances and the impersonator's mimic attempts were then processed for speaker verification on a single-phoneme basis and using combinations of several phonemes. Spectral analysis of individual phoneme segments revealed that some increase in similarity was accomplished by the mimic for certain speakers and phonemes. However, when the verification procedure was applied using features from five phonemes, the impersonator was unsuccessful in all mimic attempts.