Listening-Test-Based Annotation of Communicative Functions for Expressive Speech Synthesis

This paper is focused on the evaluation of listening test that was realized with a view to objectively annotate expressive speech recordings and further develop a limited domain expressive speech synthesis system. There are two main issues to face in this task. The first matter in issue to be taken into consideration is the fact that expressivity in speech has to be defined in some way. The second problem is that perception of expressive speech is a subjective question. However, for the purposes of expressive speech synthesis using unit selection algorithms, the expressive speech corpus has to be objectively and unambiguously annotated. At first, a classification of expressivity was determined making use of communicative functions. These are supposed to describe the type of expressivity and/or speaker’s attitude. Further, to achieve objectivity at a significant level, a listening test with relatively high number of listeners was realized. The listeners were asked to mark sentences in the corpus using communicative functions. The aim of the test was to acquire a sufficient number of subjective annotations of the expressive recordings so that we would be able to create “objective” annotation. There are several methods to obtain objective evaluation from lots of subjective ones, two of them are presented.