Mikio Tohyama

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Interaural cross-correlation coefficients (ICCCs) were measured in stereo-reproduced fields where a KEMAR (Knowles electric manikin for acoustic research) was located. These ICCCs were then compared with those in an ideal, diffuse sound field. The ICCCs in a reverberant field are not reproduced accurately using a conventional two-channel stereo-reproduction(More)
This paper investigates the significance of the magnitude or the phase in the short term Fourier spectrum for speech intelligibility as a function of the time-window length. For a wide range of window lengths (1/16-2048 ms), two hybrid signals were obtained by a cross-wise combination of the magnitude and phase spectra of speech and white noise. Speech(More)
We confirmed that a speaker's vocal individuality is contained in the inter-band correlations of narrow-band (1/4 or 1/8 octave bands) temporal envelopes. Two types of envelope correlation matrices (ECMs) were made for 53 speakers , using three utterances of an identical sentence (assuming a situation where a password for verification was stolen) so that(More)
This study investigates a signal theoretic approach to rendering acoustic events. Acoustic events modeling language (AEML) is an essential part of acoustic events rendering using an acoustic-data stream based on structured audio representation. This article mainly describes sinusoidal and envelope-modulation modeling for intelligible speech modification and(More)
The strength functions of isovector dipole resonances in the even oxygen isotopes 18∼24 O are calculated by using an extended version of the time-dependent Hartree-Fock theory known as the time-dependent density-matrix theory (TDDM). The results are compared with recent experimental data and also with a shell-model calculation. It is found that the observed(More)
Reverberation morphing from an impulse response is an inevitable 3D-audio technology as well as reverberation rendering for an immersive communication network. This paper proposes a method for reverberation morphing by relocating the poles and zeros of the transfer function. It assumes that the distance of the pole/zero locations from the unit circle in the(More)
An acoustic signal representation based on sinusoidal and envelope-modulation modeling is described. Such studies are crucial to acoustic events modeling for structured audio-signal representation and rendering through interactive networks. This paper confirmed that; (1) sinusoidal modeling is useful for constructing an intelligible speech using only a few(More)