A quantitative assessment of the relative speaker discriminating properties of phonemes

The aim of the study described in this paper is to provide a thorough and quantitative assessment of the relative speaker discriminating properties of phonemes. A VQ codebook based approach to speaker modeling is used in conjunction with a phonetically hand-labelled database to produce phoneme rankings based on speaker verification scores. In broad groupings the nasals and vowels are found to provide the best speaker recognition performance, followed by the fricatives, affricates and approximants, with the stops providing the worst performance of all. A comparison at the individual phoneme level produces a more detailed ranking and of particular interest is the surprisingly good performance of the unvoiced fricative /s/. The ranking of phonemes is found to be largely unaffected by changes in experimental parameters such as the model size, the feature type and the speaker population