Analysis and synthesis of German F0 contours by means of Fujisaki's model

Abstract

This paper presents the adaptation of Fujisaki's quantitative model to the analysis of German intonation and its application to F 0 synthesis by rule. The parameter values of the model are determined by an automatic approximation of naturally produced F 0 contours. The algorithm is not primarily based on mathematical criteria but is subject to constraints that emerge from a linguistic interpretation of the model. The potential sources of variation of the parameter values are examined using statistical methods. A set of rules is formulated that capture the effects of both linguistic and speaker-dependent features. The rules generate artificial intonation contours which in turn can be related to linguistic features such as sentence mode or word accent. Acceptability of the rule-generated intonation patterns as well as the adequate modelling of linguistic prosodic properties are evaluated perceptually by both phonetically trained subjects and prosodically “naive” listeners. In general, utterances resynthesized with rule-generated F 0 contours are judged highly acceptable and natural by both groups of listeners. Detailed judgements with respect to word accent and sentence mode are obtained that help to improve several specific rules and contribute to a more adequate description of German intonation.