Discrimination of isolated vowels and stop consonants using features extracted from onset spectrum

Place and/or manner of articulation of the 7 consonants (/?,p,t,k,b,d,g/) are discriminated in an enviroment of /a,i,u, e,o/. We considered that isolated vowels are approximately characteriszed as the glottal stop /?/ and included them as stop consonants. The feature vector used was spectrum of the initial 50ms after vowel voicing or stop burst point. The burst point of time was manually specified referring to waveform display. We used a stepwise discriminant analysis program with variable selection to classify the samples of speech. The sample set comprised 3402 samples from 89 male speakers. Some invariance was found in the discrimination between /?,p,t,k/ achieving 89% correct score across vowel context and speakers. This is a 3% degradation from that between /p,t,k/. A few samples of voiced stops lacking murmur preceding the burst point was well discriminated from voiceless stops of same point of articulation.