汉语数码语音识别分析毕业设计摘要

汉语数码语音识别分析毕业设计论文

Abstract

This paper reports a high-performance MDSR system. In the MDSR system, MFCC (Mel Frequency Cepstrum Coefficient) is used as the main feature parameter of the speech. And the formant trajectory and the nasal feature are extracted to discriminate the confusable words. The feature-based real-time endpoint detection algorithm is proposed to reduce the requirement of system resource and improve the disturbance-proof ability. The two-stage recognition frame is adopted to enhance the discriminating ability, in which the candidate words are decided in the first stage and the confusable word pairs are discriminated in the second stage.

Mandarin digit string speech recognition are studied in this paper. Mandarin digit string speech recognition is of great value in the applications of speech-dialing telephone, remote controlling of consumer devices and industrial controlling, et al. Compared with the English digit speech recognition, the mandarin digit speech recognition is still underdeveloped. The reason is due to that the confusion among the mandarin digits is fairly high and the co-articulation is relatively serious. This paper utilizes the MFCC parameters and context-independent word-based continuous HMM as the acoustic models. The segment duration information is introduced in the form of duration-dependent transition probability. In order to output multiple candidates, the multi-candidate frame-synchronous algorithm is used as the search strategy.

Speaker adaptation is one of the effective approaches to improve the performance of speaker-independent speech recognition. This paper applies the MAP algorithm to the Mandarin digit speech recognition, and discusses several approaches that accelerate the adaptaion process as well as the effects on the unadapted speakers. The experiment shows that the MAP algorithm can considerably reduce the error rate of Mandarin digit speech recognition on the adapted speaker and cause little influence on the unadapted speakers.

Keywords : Mandarin digit (string) speech recognition speaker adaptation