Development and evaluation of Polish speech corpus for unit selection speech synthesis systems

Abstract

This paper presents the results of a set of experiments assessing the perceived quality of the Polish version of the BOSS unit selection synthesis system. The experiments aimed to evaluate the potential improvement of synthesis quality by three factors pertaining to corpus structure and coverage as well as levels of corpus annotation. The three factors affecting synthesis quality were (i) manual vs. automatic corpus annotation, (ii) coverage of CVC triphones in rich intonational patterns, and (iii) coverage of complex consonant clusters. Results indicate that a manual correction of automatic annotations enhances synthesis quality. Increased coverage of CVC sequences and consonant clusters also improved the perceived synthesis quality, but the effect was smaller than anticipated.