Usability of text-to-speech synthesis to bridge the digital divide in South Africa: Language practitioner perspectives

Abstract

We report on two sets of perceptual evaluations of our South African text-to-speech voices by language practitioners. In the first evaluation, we measure baseline quality in terms of how understandable and human-like the voices sound. We also determine baseline usability by asking a series of questions related to accessibility and mainstream application settings. In the second evaluation, we employ the same criteria to compare pronunciation improvements against the baseline. The results indicate success in many areas, but also illuminate room for improvement in others, especially in the cases of the African languages.