In this paper, speech-distortion weighted (SDW) inter-frame Wiener filters (IFWFs) are investigated for singlechannel noise reduction in a filter bank structure. The filters utilize a parameter µ that explicitly sets a trade-off between noise reduction and speech distortion and have traditionally been used in multi-channel applications under the term speechdistortion weighted multichannel Wiener filter (SDW-MWF). The application of these SDW-IFWFs relies on the estimation of interframe correlation (IFC) coefficients and it is shown that the IFC coefficients can be more robustly estimated using a secondary higher resolution filter bank (HRFB). It is then shown how realvalued scalar gains, which are optimal in the primary filter bank, can be applied directly in the HRFB instead of the inter-frame filtering in the primary filter bank, which leads to a more robust noise reduction performance for any value of µ. Computing these gains is also cheaper since matrix inversions are avoided and the primary filter bank is not needed in the actual implementation. Experimental results are given that support the claims, where the proposed methods are compared to relevant reference methods using measures such as the segmental SNR and the objective PESQ.

In this paper, an adaptive time-frequency analysis scheme is proposed along with a synthesis scheme using an asymmetric window. The proposed scheme is suitable for audio noise reduction with a low delay in the range of 0 to 4 ms. The main novelty of the paper is the adaptive analysis scheme that can adapt to the incoming signal independently in both time and frequency by employing a complex filter on a DFT modulated filter bank. A number of adaptive time-frequency schemes are described that are suitable for low delay and low computational complexity. The adaptive time-frequency scheme is used for the computation of noise reduction gain factors, which are then adopted in a nonadaptive analysis/synthesis scheme. The synthesis scheme uses an asymmetric window to achieve a good tradeoff between low delay and a sharp frequency response. Examples are given of the adaptive analysis and measurements of the synthesis scheme are given to show that the filter bank has a gain dependent nonlinear phase response. Finally, a noise reduction task is performed that shows good performance compared to reference implementations in terms of segmental SNR and PESQ.

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