A Noise-Robust Continuous Speech Recognition System Using Block-Based Dynamic Range Adjustment

Yiming SUN  Yoshikazu MIYANAGA  

IEICE TRANSACTIONS on Information and Systems   Vol.E95-D    No.3    pp.844-852
Publication Date: 2012/03/01
Online ISSN: 1745-1361
DOI: 10.1587/transinf.E95.D.844
Print ISSN: 0916-8532
Type of Manuscript: PAPER
Category: Speech and Hearing
CMS,  CSR,  DRA,  noise-robust,  RSA,  

Full Text: PDF>>
Buy this Article

A new approach to speech feature estimation under noise circumstances is proposed in this paper. It is used in noise-robust continuous speech recognition (CSR). As the noise robust techniques in isolated word speech recognition, the running spectrum analysis (RSA), the running spectrum filtering (RSF) and the dynamic range adjustment (DRA) methods have been developed. Among them, only RSA has been applied to a CSR system. This paper proposes an extended DRA for a noise-robust CSR system. In the stage of speech recognition, a continuous speech waveform is automatically assigned to a block defined by a short time length. The extended DRA is applied to these estimated blocks. The average recognition rate of the proposed method has been improved under several different noise conditions. As a result, the recognition rates are improved up to 15% in various noises with 10 dB SNR.