On-Line, Real-Time Spoken Words Recognition System with Learning Capability of Speaker Differences.

Abstract

We have developed the LISTEN (LIMITED SPOKEN TEXT ENCODER) system which automatically recognizes spoken words in isolation for a limited vocabulary. This system is a subpart of the LITHAN (LISTEN-THINK-ANSWER) speech understanding system1, 2). This makes a great feature of the recognition in real time on a mini-computer. Owing to this development, it became capable of trying the various experiments on many speech data. There are other two features in this system : One is to learn the speaker differences by preliminary uttered vowels. The other is that the system is composed of two stages, i.e., phoneme recognition and word recognition. In the latter stage, the effect of coarticulation is taken into account. The system performance obtained the recognition rate of 98.0% on experiments of spoken digits that were uttered by 40 male adults. And also the system obtained the rate of 98.4% on preliminary learning by some spoken digits. When no learning procedure, however, the rate decreased to 95.8%.