On the use of instantaneous and transitional spectral information in speaker recognition

The use of instantaneous and transitional spectral representations of spoken utterances for speaker recognition is investigated. LPC derived-cepstral coefficients are used to represent instantaneous spectral information and best linear fits of each cepstral coefficient over a specified time window are used to represent transitional information. An evaluation has been carried out using a data base of isolated digit utterances over dialed-up telephone lines by 10 talkers. Two vector quantization (VQ) codebooks, instantaneous and transitional, are constructed from training utterances for each speaker. The experimental results show that the instantaneous and transitional representations are relatively uncorrelated thus providing complementary information for speaker recognition. A rectangular window of approximately 100-150 ms duration provides an effective estimate of spectral transitions for speaker recognition. Also, simple transmission channel variations are shown to affect the instantaneous spectral representations and the corresponding recognition performance significantly, while the transitional representations and performance are relatively resistant.