We proposed a new speech recognition method which integrated a VQ-distortion measure and a discrete HMM. This VQ-distortion based HMM uses a VQ-distortion measure at each state instead of a discrete output probability used by a discrete HMM. Although this method is regarded as a refined version of the VQ-distribution based recognition method proposed by Burton et al, it is also considered as a special case of a mixtured distribution density HMM. In this paper, we describe the relationship between the VQ-distortion based HMM and conventional HMMs, and compare their speech recognition performance through the experiments on speaker-independent spoken digit recognition. This new method overperformed traditional HMMs.

Keywords: HMM, VQ-distortion based HMM, spoken digit recognition