Odyssey 2008: The Speaker and Language Recognition Workshop Stellenbosch, South Africa January 21-24, 2008

Beyond the Long-Term Mean: Exploring the Potential of F0 Distribution Parameters in Traditional Forensic Speaker Recognition

Yuko Kinoshita (1), Shunichi Ishihara (2), Phil Rose (3)

(1) School of Languages and International Studies, University of Canberra, Australia
(2) Faculty of Asian Studies; (3) School of Language Studies, Faculty of Arts, The Australian National University, Canberra, Australia

Despite its many prima facie attractive properties for Forensic Speaker Recognition, F0 is regarded as having limited forensic value due to its large within-speaker variability. However, its forensic use to date has been limited mostly to its long-term mean and standard deviation. This paper examines the discriminatory potential, within a Likelihood Ratio-based approach, of additional parametric features from the distribution of long-term F0: its skew, kurtosis, modal F0 and modal density. Motivated by the observation that the overall long-term F0 distribution shows less within-speaker occasion-to-occasion difference, we report a forensic discrimination experiment with noncontemporaneous speech samples from 201 male Japanese speakers. Using a multivariate LR as discriminant distance with the six LTF0 distribution parameters, an EER of 10.7% is obtained from 201 target and 80400 non-target trials. We also investigate how the EER degrades as a function of amount of voiced speech.

Full Paper

Bibliographic reference.  Kinoshita, Yuko / Ishihara, Shunichi / Rose, Phil (2008): "Beyond the long-term mean: exploring the potential of F0 distribution parameters in traditional forensic speaker recognition", In Odyssey-2008, paper 003.