Abstract: The study proposes an algorithm for noise cancellation by using recursive least square (RLS) and pattern recognition by using fusion method of Dynamic Time Warping (DTW) and Hidden Markov Model (HMM). Speech signals are often corrupted with background noise and the changes in signal characteristics could be fast. These issues are especially important for robust speech recognition. Robustness is a key issue in speech recognition. The algorithm is tested on speech samples that are a part of a Malay corpus. It is shown that the fusion technique can be used to fuse the pattern recognition outputs of DTW and HMM. Furthermore refinement normalization was introduced by using weight mean vector to obtain better performance. Accuracy of 94 % on pattern recognition was obtainable using fusion HMM and DTW compared to 80.5 % using DTW and 90.7 % using HMM separately. The accuracy of the proposed algorithm is increased further to 98 % by utilization the RLS adaptive noise cancellation.

Current speech recognition systems perform poorly on conversational speech as compared to read speech, arguably due to the large acoustic variability inherent in conversational speech. Our hypothesis is that there are systematic effects in local context, associated with syllabic structure, that are not being captured in the current acoustic models. Such variation may be modeled using a broader definition of context than in traditional systems which restrict context to be the neighboring phonemes. In this paper, we study the use of word- and syllable-level context conditioning in recognizing conversational speech. We describe a method to extend standard tree-based clustering to incorporate a large number of features, and we report results on the Switchboard task which indicate that syllable structure outperforms pentaphones and incurs less computational cost. It has been hypothesized that previous work in using syllable models for recognition of English was limited because of ignoring the phenomenon of re-syllabification (change of syllable structure at word boundaries), but our analysis shows that accounting for re-syllabification does not impact recognition performance.

Abstract: This paper is presents a pattern recognition fusion method for isolated Malay digit recognition using Dynamic Time Warping (DTW) and Hidden Markov Model (HMM). The aim of the project is to increase the accuracy percentage of Malay speech recognition. This study proposes an algorithm for pattern recognition fusion of the recognition models. The endpoint detection, framing, normalization, Mel Frequency Cepstral Coefficient (MFCC) and vector quantization techniques are used to process speech samples to accomplish the recognition. Pattern recognition fusion method is then used to combine the results of DTW and HMM which uses weight mean vectors. The algorithm is tested on speech samples that are a part of a Malay corpus. This paper has shown that the fusion technique can be used to fuse the pattern recognition outputs of DTW and HMM. Furthermore it also introduced refinement normalization by using weight mean vector to get better performance with accuracy of 94 % on pattern recognition fusion HMM and DTW. Unlikely accuracy for DTW and HMM, which is 80.5 % and 90.7 % respectively.