BEYOND INTELLIGIBILITY - THE PERFORMANCE OF TEXT-TO-SPEECH SYNTHESIZERS

Performance assessment tests using opinion scales and subjective measu res have long been used as the basis for rating the speech quality of telephony transmission systems. Recently these methods have been adapt ed to speech synthesiser evaluation and used to develop a standard tes t methodology which has been applied to most of the text-to-speech sys tems which are currently available in the market. In the course of thi s work a new reference has been defined. The procedure draws heavily u pon current CCITT(ITU) Recommendations relating to subjective evaluati on and enables comparisons to be made between results obtained in diff erent experiments. The results indicate that comparisons made using th e new reference system are consistent across subject groups and are to lerant to different types of speech material and opinion scoring metho ds.