Abstract: The present invention automatically determines sound duration values, based on context, for phonetic symbols which are produced during text-to-speech conversion. The context-dependent and static attributes of the phonetic symbols are checked and specified. Then, the phonetic symbols are processed by a set of sequential duration-specification rules which set the duration value for each phonetic symbol.

Abstract: In a synthetic speech system intonation of a natural utterance is automatically applied to a synthesized utterance. The present invention applies the desired intonation of the natural utterance to the synthesized utterance by aligning voicing sections of the natural utterance to the synthesized utterance. The voicing sections are initially delineated by voiced versus unvoiced, based on default voicing specifications for the synthetic utterance and on pitch tracker analysis of the natural utterance, and an attempt is made to align individual sections thereby. If no initial alignment occurs then a further attempt is made by varying the default voicing specifications of the synthesized utterance. If alignment is still not achieved, then each of the utterances, natural and synthetic, is considered a single large voicing section, which thus forces alignment therebetween.