Yohei Kawaguchi

Learn More
In this paper, we propose a head-orientation estimation method from multichannel acoustic signals. Sharpness of a DOA histogram which is extracted by using the sparseness based DOA estimation method varies depending on the head orientation of a speaker. The proposed method utilizes this phenomenon to estimate the head orientation of the speaker. The(More)
We propose a novel non-stationary and convolutive noise reduction method under reverberant environments. Unlike many multichan-nel noise reduction methods, the proposed method does not need pre knowledge of impulse response or direction of arrival (DOA) of the target source. The proposed method is composed of two processes. On the noise reduction process,(More)
We propose a new method to separate mass spectra into components of each chemical compound for explosives detection. In mass spectra , all components have no negative values. However, conventional factor analyses for basis decomposition use no constraints of non-negativity, and we can not apply these methods to mass spectra. The proposed method is based on(More)
We propose a novel beamforming method that is complementarily combined with the time-frequency domain independent component analysis (TF-ICA). Under reverberant environments, performance of TF-ICA is known to be limited. On the other hand, when time period in which there are only noise sources (noise-only period) is given, beamforming based on multichannel(More)
In this paper, we propose a novel acoustic-echo-reduction technique at a time-frequency domain, which is optimally combined with speech enhancement. Unlike conventional echo reduction techniques which minimizes only residual power of the far-end acoustic echo signal, the proposed method minimizes summation of the residual echo signal and distortion of the(More)
We propose an optimized speech enhancement method that combines acoustic echo reduction, speech dereverberation, and noise reduction in a unified framework. Normally, partial optimization of acoustic echo reduction, speech dereverberation, and noise reduction does not lead to total optimization. A cascade method of multiple functions causes mutual(More)