Many text recognition systems recognize text imagery at the character level and assemble words from the recognized characters. An alternative approach is to recognize text imagery at the word level, without analyzing individual characters. This approach avoids the problem of individual character segmentation, and can overcome local errors in character recognition. A word-level recognition syste...

In extensive experiments, the recognition score of a speaker independent isolated word speech recognition system based on a continuous density HMM (CDHMM) has been measured in the presence of real life noises in various SNRs. In all experiments the results show improvement in the mean recognition score when the subband adaptive filtering LMS method is used in comparison to the full-band LMS met...

In this paper, we describe new techniques to signi cantly reduce computational, storage and memory access requirements of a tied-mixture HMM based speech recognition system. Although continuous mixture HMMs o er improved recognition performance, we show that tied-mixture HMMs may o er signi cant advantage in complexity reduction for low-cost implementations. In particular, we consider two tasks...

Automatic Speech Recognition (ASR) has matured into a technology which is becoming more common in our everyday lives, and is emerging as a necessity to minimise driver distraction when operating in-car systems such as navigation and infotainment. In “noise-free” environments, word recognition performance of these systems has been shown to approach 100%, however this performance degrades rapidly...

Conventional HMMs have weak duration constraints. In noisy conditions, the mismatch between corrupted speech signals and models trained on clean speech may cause the decoder to produce word matches with unrealistic durations. This paper presents a simple way to incorporate word duration constraints by unrolling HMMs to form a lattice where word duration probabilities can be applied directly to ...

BACKGROUND So that portions of the classic Miller, Heise, and Lichten (1951) study could be replicated, new recorded versions of the words and digits were made because none of the three common monosyllabic word lists (PAL PB-50, CID W-22, and NU-6) contained the 9 monosyllabic digits (1-10, excluding 7) that were used by Miller et al. It is well established that different psychometric character...