Speech technology for the visually impaired - the Swedish perspective

Fundamental speech research at the Department of Speech Communication & Music Acoustics, KTH, has lead to a multi-lingual text-to-speech system and a speech recognition device. Both are presently put to use by the visually impaired. To this date over five hundred text-to-speech systems are delivered, most of them to applications for the visually impaired. Some of these applications will be described including software for screen access, reading machines and a radio-distributed daily newspaper experiment. In some applications, simple speech coding techniques suffice, as in a cuing system that recently has been successfully introduced. Some present and future research topics, that will lead to improved speech technology aids for visually impaired persons, will also be discussed. Speech technology research in Sweden Fundamental speech research at the Department of Speech Communication and Music Acoustics, KTH, has lead to a multi-lingual text-tospeech system and a speech recognition device (Magnusson, Blomberg, Carlson, Elenius & Granstrijm, 1984). Both products are now put to use by the visually impaired. Present research topics include improved models for speech production especially modelling the glottal source and the interaction between the source and the vocal tract. Articulatory models are also studied. At Chalmers Technical University in Gothenburg, an experimental text-to-speech system has been built along fhese lines. I-bwever, it is still true that the factor limiting the speech quality today is not the model per se but the detailed phonetic knowledge implemented in the rule synthesis programs. A speech data hase has been created to study phonetic realizations in detail. Different reading styles and speaker characteristics are also studied in order to improve speech synthesis quality and flexibility. International perspective Speech technoloq has grown considerably during the last decade, both on the research and commercial developments. Several market projections around 1980 showed multi-billion dollar markets before 1990. * Contribution to the Workshop on "Communication Systems for the Blind", Florence, Italy, bbvember 18-20, 1986.