Hiroaki Yamajo
Nara Institute of Science and Technology
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Publication
Featured researches published by Hiroaki Yamajo.
IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences | 2005
Hiroshi Saruwatari; Hiroaki Yamajo; Tomoya Takatani; Tsuyoki Nishikawa; Kiyohiro Shikano
We propose a new two-stage blind separation and deconvolution strategy for multiple-input multiple-output (MIMO)-FIR systems driven by colored sound sources, in which single-input multiple-output (SIMO)-model-based ICA (SIMO-ICA) and blind multichannel inverse filtering are combined. SIMO-ICA can separate the mixed signals, not into monaural source signals but into SIMO-model-based signals from independent sources as they are at the microphones. After the separation by the SIMO-ICA, a blind deconvolution technique for the SIMO model can be applied even when each source signal is temporally correlated and the mixing system has a nonminimum phase property. The simulation results reveal that the proposed algorithm can successfully achieve separation and deconvolution of a convolutive mixture of speech, and outperforms a number of conventional ICA-based BSD methods.
Statistical Signal Processing, 2003 IEEE Workshop on | 2004
Hiroshi Saruwatari; Hiroaki Yamajo; Tomoya Takatani; Tsuyoki Nishikawa; Kiyohiro Shikano
We propose a new two-stage blind separation and deconvolution algorithm for multiple-input multiple-output (MIMO)-FIR system driven by colored sound sources, in which a new single-input multiple-output (SIMO)-model-based ICA (SIMO-ICA) and blind multichannel inverse filtering are combined. SIMO-ICA can separate the mixed signals, not into monaural source signals but into SIMO-model-based signals from independent sources. After SIMO-ICA, a simple blind deconvolution technique for the SIMO model can be applied even when each source signal is temporally correlated. The simulation results reveal that the proposed algorithm can successfully achieve the separation and deconvolution for a convolutive mixture of speech.
international symposium on neural networks | 2003
Hiroshi Saruwatari; Hiroaki Yamajo; Tomoya Takatani; Tsuyoki Nishikawa; Kiyohiro Shikano
We propose a two-stage blind separation and deconvolution (BSD) algorithm for a convolutive mixture of temporally correlated signals, in which a new single-input multiple-output (SIMO)-model-based ICA (SIMO-ICA) and blind multichannel inverse filtering are combined. SIMO-ICA consists of multiple ICAs and a fidelity controller, and each ICA runs in parallel under fidelity control of the entire separation system. SIMO-ICA can separate the mixed signals, not into monaural source signals but into SIMO-model-based signals from independent sources as they are at the microphones. After the separation by SIMO-ICA, a simple blind deconvolution technique based on multichannel inverse filtering for the SIMO model can be applied even when the mixing system is the nonminimum phase system and each source signal is temporally correlated. The experimental results obtained under the reverberant condition reveal that the sound quality of the separated signals in the proposed method is superior to that in the conventional ICA-based BSD.
2003 IEEE XIII Workshop on Neural Networks for Signal Processing (IEEE Cat. No.03TH8718) | 2003
Hiroshi Saruwatari; Hiroaki Yamajo; Tomoya Takatani; Tsuyoki Nishikawa; Kiyohiro Shikano
We propose a new two-stage blind separation and deconvolution algorithm for multiple-input multiple-output (MIMO)- FIR system driven by colored sound sources, in which a new single-input multiple-output (SIMO)-model-based ICA (SIMO-ICA) and blind multichannel inverse filtering are combined. SIMO-ICA can separate the mixed signals, not into monaural source signals but into SIMO-model-based signals from independent sources. After SIMO-ICA, a simple blind deconvolution technique for the SIMO model can be applied even when each source signal is temporally correlated. The simulation results reveal that the proposed algorithm can successfully achieve the separation and deconvolution for a convolutive mixture of speech.
ieee antennas and propagation society international symposium | 2005
Hiroshi Saruwatari; Hiroaki Yamajo; Tomoya Takatani; Tsuyoki Nishikawa; Kiyohiro Shikano
The paper describes a novel two-stage blind separation and deconvolution algorithm for a multiple-input multiple-output FIR system driven by colored sources, in which a new single-input multiple-output (SIMO)-model-based ICA (SIMO-ICA) and blind multichannel inverse filtering are combined. SIMO-ICA can separate the mixed signals, not into monaural source signals, but into SIMO-model-based signals from independent sources. After SIMO-ICA, all SIMO blind deconvolution can be applied, even when each source signal is temporally correlated. Experimental results reveal that the proposed algorithm can successfully achieve separation and deconvolution for a convolutive mixture of speech signals.
ICA | 2003
Hiroshi Saruwatari; Tomoya Takatani; Hiroaki Yamajo; Tsuyoki Nishikawa; Kiyohiro Shikano
Archive | 2003
Hiroaki Yamajo; Hiroshi Saruwatari; Tomoya Takatani; Tsuyoki Nishikawa; Kiyohiro Shikano
european signal processing conference | 2004
Hiroaki Yamajo; Hiroshi Saruwatari; Tomoya Takatani; Tsuyoki Nishikawa; Kiyohiro Shikano
Archive | 2004
Hiroshi Saruwatari; Tomoya Takatani; Hiroaki Yamajo; Kiyohiro Shikano
conference of the international speech communication association | 2003
Hiroaki Yamajo; Hiroshi Saruwatari; Tomoya Takatani; Tsuyoki Nishikawa; Kiyohiro Shikano