Speech synthesis, Speech simulation and speech science

Speech synthesis research has been transformed in recent years through the exploitation of speech corpora - both for statistical modelling and as a source of signals for concatenative synthesis. This revolution in methodology and the new techniques it brings calls into question the received wisdom that better computer voice output will come from a better understanding of how humans produce speech. This paper discusses the relationship between this new technology of simulated speech and the traditional aims of speech science. The paper suggests that the goal of speech simulation frees engineers from inadequate linguistic and physiological descriptions of speech. But at the same time, it leaves speech scientists free to return to their proper goal of building a computational model of human speech production

RELATING PHONETIC AND PHONOLOGICAL CATEGORIES

Recent proposals to treat phonetic representations as the semantic interpretation of phonological representations are technically problematic to implement. The main difficulty is that phonological representations are discrete while phonetic representations are continuous which makes the standard method of describing semantic interpretation as a homomorphism between sortally equivalent algebras hard to generalize. The paper solves the technical problem by introducing a notion of homomorphisms. First, the operation of concatenation is defined in the usual way for strings and as `continuation' for continuous scalar-vector functions with finite support, and the set of phonetic representations is equipped with a measure. Next a.e. homomorphisms are rigorously defined and the semantic relationship between phonological and phonetic categories is made explicit in terms of these homomorphisms. Finally constant target (triphone) models, which play a central role in speech recognition, are reconstructed in this semantic framework