Efficient utilization of variable duration information in HMM based HWR systems
A. Kundu, Yang He, Mou-Yen Chen · 2002
We describe an MD-HMM (model discriminant HMM) based handwritten word recognition (HWR) system (called NEHMM-nonergodic HMM) whose system parameters are derived from the parameters of the VDHMM (variable duration HMM) system described by Chen, Kundu and Srihari (see IEEE Trans. on Image Proc., vol.4, no.12, p.1675-88, 1995). The new HMM achieves better experimental results by a more efficient utilization of variable duration information. However, more often the problem is 'reliable computation' of duration probabilities given limited databases. A scheme (VSLHMM-variable sequence length HMM) has been presented to avoid the computation of duration probabilities altogether without sacrificing the performance gain of the VDHMM system.