This article introduces fractional Fourier transform (FrFT) to speech enhancement, A novel algorithm is proposed for the estimation of FrFT order. The determination of the optimal FrFT order is a crucial issue for FrFT. We use the information of pitches, harmonies and formants in correlogram of Gammatone filterbank to get a few candidates of the transform order. The proposed method reduces the computation complexity in the searching of optimal transform order. The experimental results of speech enhancement show that the proposed method is superior to the conventional spectral subtraction in the sense of SNR improvement of the enhanced speeches and the Itakura-Saito distance of LPC coefficients.
['Duo-jia Ma', 'Xiang Xie', 'Jingming Kuang']
A novel algorithm of seeking FrFT order for speech enhancement