On the effects of accent and language on low rate speech coders

Telecommunications networks are exposed to a plethora of accents and languages. Fundamental to current and future systems are low rate speech coders. The paper examines the problems associated with speech coding of different languages and accents. The investigations show that most low-rate (8 kb/s and below) speech coders show bias towards non-accented English. When the coders are used for heavily accented English or other languages, significant performance degradation is noted. The paper examines the reasons for such variations and some approaches for improving coder performance.