Change search
ReferencesLink to record
Permanent link

Direct link
A New Linear MMSE Filter for Single Channel Speech Enhancement Based on Nonnegative Matrix Factorization
KTH, School of Electrical Engineering (EES), Sound and Image Processing.
KTH, School of Electrical Engineering (EES), Sound and Image Processing.
KTH, School of Electrical Engineering (EES), Sound and Image Processing.
2011 (English)In: IEEE Workshop on Applications of Signal Processing to Audio and Acoustics, WASPAA 2011, IEEE , 2011Conference paper (Refereed)
Abstract [en]

In this paper, a linear MMSE filter is derived for single-channelspeech enhancement which is based on Nonnegative Matrix Factorization(NMF). Assuming an additive model for the noisy observation,an estimator is obtained by minimizing the mean square errorbetween the clean speech and the estimated speech components inthe frequency domain. In addition, the noise power spectral density(PSD) is estimated using NMF and the obtained noise PSD is usedin a Wiener filtering framework to enhance the noisy speech. Theresults of the both algorithms are compared to the result of the sameWiener filtering framework in which the noise PSD is estimatedusing a recently developed MMSE-based method. NMF based approachesoutperform the Wiener filter with the MMSE-based noisePSD tracker for different measures. Compared to the NMF-basedWiener filtering approach, Source to Distortion Ratio (SDR) is improvedfor the evaluated noise types for different input SNRs usingthe proposed linear MMSE filter.

Place, publisher, year, edition, pages
IEEE , 2011.
Keyword [en]
Speech enhancement, nonnegative matrix factorization, Linear MMSE filter
National Category
Engineering and Technology
URN: urn:nbn:se:kth:diva-42589DOI: 10.1109/ASPAA.2011.6082303ISI: 000298302900012ScopusID: 2-s2.0-83455182002OAI: diva2:447319
IEEE Workshop on Applications of Signal Processing to Audio and Acoustics. New Paltz, NY. October 16-19 2011
EU, European Research Council, 2008-214699

QC 20111116

Available from: 2012-10-31 Created: 2011-10-11 Last updated: 2013-09-16Bibliographically approved
In thesis
1. Speech Enhancement Using Nonnegative MatrixFactorization and Hidden Markov Models
Open this publication in new window or tab >>Speech Enhancement Using Nonnegative MatrixFactorization and Hidden Markov Models
2013 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Reducing interference noise in a noisy speech recording has been a challenging task for many years yet has a variety of applications, for example, in handsfree mobile communications, in speech recognition, and in hearing aids. Traditional single-channel noise reduction schemes, such as Wiener filtering, do not work satisfactorily in the presence of non-stationary background noise. Alternatively, supervised approaches, where the noise type is known in advance, lead to higher-quality enhanced speech signals. This dissertation proposes supervised and unsupervised single-channel noise reduction algorithms. We consider two classes of methods for this purpose: approaches based on nonnegative matrix factorization (NMF) and methods based on hidden Markov models (HMM).

 The contributions of this dissertation can be divided into three main (overlapping) parts. First, we propose NMF-based enhancement approaches that use temporal dependencies of the speech signals. In a standard NMF, the important temporal correlations between consecutive short-time frames are ignored. We propose both continuous and discrete state-space nonnegative dynamical models. These approaches are used to describe the dynamics of the NMF coefficients or activations. We derive optimal minimum mean squared error (MMSE) or linear MMSE estimates of the speech signal using the probabilistic formulations of NMF. Our experiments show that using temporal dynamics in the NMF-based denoising systems improves the performance greatly. Additionally, this dissertation proposes an approach to learn the noise basis matrix online from the noisy observations. This relaxes the assumption of an a-priori specified noise type and enables us to use the NMF-based denoising method in an unsupervised manner. Our experiments show that the proposed approach with online noise basis learning considerably outperforms state-of-the-art methods in different noise conditions.

 Second, this thesis proposes two methods for NMF-based separation of sources with similar dictionaries. We suggest a nonnegative HMM (NHMM) for babble noise that is derived from a speech HMM. In this approach, speech and babble signals share the same basis vectors, whereas the activation of the basis vectors are different for the two signals over time. We derive an MMSE estimator for the clean speech signal using the proposed NHMM. The objective evaluations and performed subjective listening test show that the proposed babble model and the final noise reduction algorithm outperform the conventional methods noticeably. Moreover, the dissertation proposes another solution to separate a desired source from a mixture with arbitrarily low artifacts.

 Third, an HMM-based algorithm to enhance the speech spectra using super-Gaussian priors is proposed. Our experiments show that speech discrete Fourier transform (DFT) coefficients have super-Gaussian rather than Gaussian distributions even if we limit the speech data to come from a specific phoneme. We derive a new MMSE estimator for the speech spectra that uses super-Gaussian priors. The results of our evaluations using the developed noise reduction algorithm support the super-Gaussianity hypothesis.

Place, publisher, year, edition, pages
Stockholm: KTH Royal Institute of Technology, 2013. xiv, 52 p.
Trita-EE, ISSN 1653-5146 ; 2013:030
Speech enhancement, noise reduction, nonnegative matrix factorization, hidden Markov model, probabilistic latent component analysis, online dictionary learning, super-Gaussian distribution, MMSE estimator, temporal dependencies, dynamic NMF
National Category
Electrical Engineering, Electronic Engineering, Information Engineering
urn:nbn:se:kth:diva-124642 (URN)978-91-7501-833-1 (ISBN)
Public defence
2013-10-18, Lecture Room F3, Lindstedtsvägen 26, KTH, Stockholm, 13:00 (English)

QC 20130916

Available from: 2013-09-16 Created: 2013-07-24 Last updated: 2013-10-09Bibliographically approved

Open Access in DiVA

fulltext(324 kB)218 downloads
File information
File name FULLTEXT02.pdfFile size 324 kBChecksum SHA-512
Type fulltextMimetype application/pdf

Other links

Publisher's full textScopusIEEEXplore

Search in DiVA

By author/editor
Mohammadiha, NasserGerkmann, TimoLeijon, Arne
By organisation
Sound and Image Processing
Engineering and Technology

Search outside of DiVA

GoogleGoogle Scholar
Total: 218 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 258 hits
ReferencesLink to record
Permanent link

Direct link