A new approach to English text-to-phoneme conversion using Delta, version 2

The Delta System, version 2 is being used to develop a new set of text-to-speech rules for English. This paper focuses on the text-to-phoneme portion of these rules. These text-to-phoneme rules are based on an earlier rule set developed by Hertz [J. Acoust. Soc. Am. Suppl. 1 69, S83 (1981)], but are much more elegant and complete, taking advantage of Delta's flexible facilities for building multilevel utterance representations and matching patterns against them. The rules convert an input text into an utterance representation containing the lexical, morphological, and phonological structure of the utterance. Sophisticated algorithms are used for identifying prefixes (productive and nonproductive ones), suffixes, and roots (including the roots of compound words), for predicting lexical stress, for assigning grammatical categories, and for predicting pronunciations. Portions of these algorithms will be described, with a focus on how the Delta programming language allows them to be expressed succinctly and clearly. The rules will be available for demonstration.