Donald S. Williamson

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Binary time-frequency masking and model-based nonnegative matrix factorization (NMF) are two common approaches to speech separation. However, binary masking often suffers from poor perceptual quality, while NMF typically requires pretrained models for both speech and noise and frequently does not perform well. In this paper we examine whether a single or(More)
The phase response of noisy speech has largely been ignored, but recent research shows the importance of phase for perceptual speech quality. A few phase enhancement approaches have been developed. These systems, however, require a separate algorithm for enhancing the magnitude response. In this paper, we present a novel framework for performing monaural(More)
Speech separation systems usually operate on the short-time Fourier transform (STFT) of noisy speech, and enhance only the magnitude spectrum while leaving the phase spectrum unchanged. This is done because there was a belief that the phase spectrum is unimportant for speech enhancement. Recent studies, however, suggest that phase is important for(More)
Recent systems for automatically identifying the performing artist from the acoustic signal of music have demonstrated reasonably high accuracy when discriminating between hundreds of known artists. A well-documented issue, however, is that the performance of these systems degrades when music from different albums is used for training and evaluation.(More)
This study proposes an approach to improve the perceptual quality of speech separated by binary masking through the use of reconstruction in the time-frequency domain. Non-negative matrix factorization and sparse reconstruction approaches are investigated, both using a linear combination of basis vectors to represent a signal. In this approach, the(More)
Speech separation based on time-frequency masking has been shown to improve intelligibility of speech signals corrupted by noise. A perceived weakness of binary masking is the quality of separated speech. In this paper, an approach for improving the perceptual quality of separated speech from binary masking is proposed. Our approach consists of two stages,(More)
This paper presents an approach for improving the perceptual quality of speech separated from background noise at low signal-to-noise ratios. Our approach uses two stages of deep neural networks, where the first stage estimates the ideal ratio mask that separates speech from noise, and the second stage maps the ratio-masked speech to the clean speech(More)
As a means of speech separation, time-frequency masking applies a gain function to the time-frequency representation of noisy speech. On the other hand, nonnegative matrix factorization (NMF) addresses separation by linearly combining basis vectors from speech and noise models to approximate noisy speech. This paper presents an approach for improving the(More)
Traditional speech separation systems enhance the magnitude response of noisy speech. Recent studies, however, have shown that perceptual speech quality is significantly improved when magnitude and phase are both enhanced. These studies, however, have not determined if phase enhancement is beneficial in environments that contain reverberation as well as(More)