Unit selection synthesis using long non-uniform units and phonemic identity matching

This paper investigates two ways of improving synthesis quality: to maximise the length of selected units or to capitalise on phonemic context. For the former, it compares a synthesiser using a novel way of target specification and unit search with a standard unit selection synthesiser. For the latter, weights for phonemic context are set differently according to the distance of the phoneme concerned from the target diphone, and according to the class (consonant/vowel) to which the phoneme in question belongs. Both ways lead to improvements, at least when the speech database is small in size.