14thAnnual Conference of the International Speech Communication Association

Lyon, France
August 25-29, 2013

Artificial Bandwidth Extension Based on Regularized Piecewise Linear Mapping with Discriminative Region Weighting and Long-Span Features

Nguyen Duc Duy, Masayuki Suzuki, Nobuaki Minematsu, Keikichi Hirose

University of Tokyo, Japan

Artificial Bandwidth Extension (ABE) has been introduced to improve perceived speech quality and intelligibility of narrow-band telephone speech. Most of the existing algorithms divided ABE into 2 sub-problems, namely extension of the excitation signal and that of the spectral envelope. In this paper, we propose a new method for spectral envelope extension based on REgularized piecewise linear mapping with DIscriminative region weighting And Longspan features (REDIAL). REDIAL is a revised version of SPLICE, a well-known method for speech enhancement. In REDIAL, however, discriminative model is introduced for space division step of the original SPLICE. The proposed REDIAL-based method approximates non-linear transformation from narrowband features to their wideband counterpart by a summation of piecewise linear transformations. The proposed method was compared with the widely used GMM-based method, through objective and subjective evaluations in both speaker-dependent and speaker-independent conditions. Both evaluations showed that the proposed method significantly outperforms the conventional GMM-based method.

Full Paper

Bibliographic reference.  Duy, Nguyen Duc / Suzuki, Masayuki / Minematsu, Nobuaki / Hirose, Keikichi (2013): "Artificial bandwidth extension based on regularized piecewise linear mapping with discriminative region weighting and long-Span features", In INTERSPEECH-2013, 3453-3457.