Web Services Based Hybrid Recognizer of Lithuanian Voice Commands

This paper presents the recently developed medical-pharmaceutical informative system with voice user interface. This is the first computerized system oriented towards healthcare services and industry where Lithuanian voice commands are used as a primary mean for control. Another essential property of the developed system is its hybrid nature: two different recognizers - an adapted commercial Spanish speech recognizer available from Microsoft and a locally developed HMM speech recognizer based on Lithuanian acoustic models - are operating in parallel. The recognition hypotheses produced by those recognizers are joined together using logical rules obtained using decision rules induction algorithms such as Ripper. All these measures and approaches allowed achieve very high speaker independent voice commands recognition accuracy acceptable for the system implementation in practice. The best achieved recognition was 98.9 % for 1000 Lithuanian voice commands. The paper presents optimization issues related with the development of the system.