tailieunhanh - báo cáo hóa học:" Research Article Compact Acoustic Models for Embedded Speech Recognition"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research Article Compact Acoustic Models for Embedded Speech Recognition | Hindawi Publishing Corporation EURASIP Journal on Audio Speech and Music Processing Volume 2009 Article ID 806186 12 pages doi 2009 806186 Research Article Compact Acoustic Models for Embedded Speech Recognition Christophe Levy Georges Linares and Jean-Francois Bonastre 339 Chemin des Meinajaries 84911 Avignon Cedex 9 France Correspondence should be addressed to Christophe Levy Received 12 March 2009 Revised 8 July 2009 Accepted 20 October 2009 Recommended by Joe Picone Speech recognition applications are known to require a significant amount of resources. However embedded speech recognition only authorizes few KB of memory few MIPS and small amount of training data. In order to fit the resource constraints of embedded applications an approach based on a semicontinuous HMM system using state-independent acoustic modelling is proposed. A transformation is computed and applied to the global model in order to obtain each HMM state-dependent probability density functions authorizing to store only the transformation parameters. This approach is evaluated on two tasks digit and voice-command recognition. A fast adaptation technique of acoustic models is also proposed. In order to significantly reduce computational costs the adaptation is performed only on the global model using related speaker recognition adaptation techniques with no need for state-dependent data. The whole approach results in a relative gain of more than 20 compared to a basic HMM-based system fitting the constraints. Copyright 2009 Christophe Levy et al. This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited. 1. Introduction The amount and the diversity of services offered by the latest generation of mobile phones and similar embedded devices has increased significantly during the last decade and these new .