Designing Syllable Models for an HMM Based Speech Recognition System

摘要

In this paper we present novel ways of incorporating syllable information into an HMM based speech recognition system. Syllable based acoustic modelling is appealing as syllables have certain acoustic-phonetic dependencies that can not be modeled in a pure phone based system. On the other hand, syllable based systems suffer from sparsity issues. In this paper we investigate the potential of different acoustic units such as phone, phone clusters, phones-in-syllables, demi-syllables and syllables in combination with a variety of back-off schemes. Experimental results are presented on the Wall Street Journal database. When working with traditional frame based features only, results only show minor improvements. However, we expect that the developed system will show its full potential when incorporating additional segmental features at the syllable level.