Pronunciation modeling using finite state transducers

This paper describes some experiments with pronunciation modeling for spontaneous speech in European Portuguese. The transducer framework provides an elegant way to combine a pronunciation lexicon of canonical forms with alternative pronunciation rules. The main phonological aspects that the rules are intended to cover are: vowel devoicing, deletion and coalescence, voicing assimilation, and simplification of consonantal clusters, both within words and across word boundaries. Our aligner proved sufficiently robust to be able to process fairly long dialogs with overlapping turns, despite many limitations, namely in terms of absence of models for voice quality changes.