Robust speech recognition using near-field superdirective beamforming with post-filtering

McCowan, Iain; Marro, Claude; Mauuary, Laurent

doi:10.1109/icassp.2000.862084

Cited by 31 publications

(21 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The work of Omologo [5] and McCowan [6] indicated that microphone arrays can be an effective alternative to close-talking microphones for single talker ASR in environments characterised by noise or multiple acoustic sources. For multitalker environments such as meetings, talker overlap is extremely common.…”

Section: Introductionmentioning

confidence: 99%

A digital microphone array for distant speech recognition

Zwyssig

Lincoln

Renals

2010

2010 IEEE International Conference on Acoustics, Speech and Signal Processing

View full text Add to dashboard Cite

In this paper, the design, implementation and testing of a digital microphone array is presented. The array uses digital MEMS microphones which integrate the microphone, amplifier and analogue to digital converter on a single chip in place of the analogue microphones and external audio interfaces currently used. The device has the potential to be smaller, cheaper and more flexible than typical analogue arrays, however the effect on speech recognition performance of using digital microphones is as yet unknown. In order to evaluate the effect, an analogue array and the new digital array are used to simultaneously record test data for a speech recognition experiment. Initial results employing no adaptation show that performance using the digital array is significantly worse (14% absolute WER) than the analogue device. Subsequent experiments using MLLR and CMLLR channel adaptation reduce this gap, and employing MLLR for both channel and speaker adaptation reduces the difference between the arrays to 4.5% absolute WER.

show abstract

Section: Introductionmentioning

confidence: 99%

A digital microphone array for distant speech recognition

Zwyssig

Lincoln

Renals

2010

2010 IEEE International Conference on Acoustics, Speech and Signal Processing

View full text Add to dashboard Cite

show abstract

“…It also fundamentally differs from other multi-channel approaches in the way it makes use of spatial information. Instead of filtering the corrupted signal to retrieve the sources (McCowan et al, 2000;Low et al, 2004, Seltzer et al, 2004a) the time-frequency plane is partitioned into disjoint regions each assigned to a particular source. A key aspect of the model is the histogram peak detection.…”

Section: Discussionmentioning

confidence: 99%

Time-Frequency Masking: Linking Blind Source Separation and Robust Speech Recognition

Kühne¹,

Togneri²,

Nordholm³

2008

Speech Recognition

View full text Add to dashboard Cite

“…Let denote a threshold value of the LNS for the detection of transients at the beamformer output (i.e., accept if and accept otherwise). Then, the false alarm and detection probabilities are, respectively, defined by (18) (19) Since is approximately chi-square distributed with degrees of freedom (see Appendix A)…”

Section: A Detection Of Transients At the Beamformer Outputmentioning

confidence: 99%

“…This structure has been further analyzed by Marro et al [2]. McCowan et al used a near-field super-directive beamforming and investigated the effect of a Wiener post-filter on speech recognition performance [19]. They showed that in the case of nearfield sources and diffuse noise conditions, improved recognition performance can be achieved compared with conventional adaptive beamformers.…”

mentioning

confidence: 99%

Multichannel Post-Filtering in Nonstationary Noise Environments

Cohen

2004

IEEE Trans. Signal Process.

View full text Add to dashboard Cite

Abstract-In this paper, we present a multichannel post-filtering approach for minimizing the log-spectral amplitude distortion in nonstationary noise environments. The beamformer is realistically assumed to have a steering error, a blocking matrix that is unable to block all of the desired signal components, and a noise canceller that is adapted to the pseudo-stationary noise but not modified during transient interferences. A mild assumption is made that a desired signal component is stronger at the beamformer output than at any reference noise signal, and a noise component is strongest at one of the reference signals. The ratio between the transient power at the beamformer output and the transient power at the reference noise signals is used to indicate whether such a transient is desired or interfering. Based on a Gaussian statistical model and combined with an appropriate spectral enhancement technique, we derive estimators for the signal presence probability, the noise power spectral density, and the clean signal. The proposed method is tested in various nonstationary noise environments. Compared with single-channel post-filtering, a significantly reduced level of nonstationary noise is achieved without further distorting the desired signal components.Index Terms-Acoustic noise measurement, adaptive signal processing, array signal processing, signal detection, spectral analysis, speech enhancement.

show abstract

Robust speech recognition using near-field superdirective beamforming with post-filtering

Cited by 31 publications

References 6 publications

A digital microphone array for distant speech recognition

A digital microphone array for distant speech recognition

Time-Frequency Masking: Linking Blind Source Separation and Robust Speech Recognition

Multichannel Post-Filtering in Nonstationary Noise Environments

Contact Info

Product

Resources

About