Yamaha Corporation

Takashi Yamakawa

Koji Kushida

Yuji Ikegaya

Satoshi Ukai

Yasushi Shimizu

Masato Hata

Mai Koike

Kenichi Tamiya

Ken Iwayama

A sound collection method and a microphone array estimate at least one sound source direction and form a plurality of sound collection beams in the estimated plurality of sound source direction, using sound collection signals of a plurality of microphones. The number of sound source directions estimated is smaller than the number of sound collection beams formed.

Array microphone and sound collection method

A sound collection method includes estimating at least one sound source direction and forming a plurality of sound collection beams in the estimated plurality of sound source direction, using sound collection signals of a plurality of microphones. The number of sound source directions estimated is smaller than the number of sound collection beams formed.

A sound emission and collection device includes a speaker, a filter processing a sound emission signal, microphones, echo cancellers cancelling regression sound signals of the sound emitted by the speaker from the sound collection signals of the corresponding microphones, a first integration section integrating adaptive filter coefficients taken out from the plurality of echo cancellers, a reverberation time estimation section estimating the reverberation time for each frequency band in the space in which the speaker and the plurality of microphones are present on the basis of the integrated adaptive filter coefficient, and an arithmetic operation section specifying a frequency band having a long reverberation time from the sound emission signal based on the estimated reverberation time, calculating a filter coefficient for suppressing power of the specified frequency band, and setting the filter coefficient to the filter.

Sound emission and collection device, and sound emission and collection method

Whereas a high masking effect can be secured in a space to which a masking sound is emitted, the degree of a discomfort a person existing in the space suffers can be reduced. In superimposition processing, a CPUextracts sound signals in different intervals of a sound signal X-n of a human voice, superimposes the extracted sound signals on each other on the time axis, and outputs a resulting superimposed sound signal X-n. In shift and addition processing, the CPU 12 interchanges a sound signal, before a reference position, of a sound signal X-n and a sound signal, after the reference position, of the sound signal X-n (shift processing) and outputs a sound signal X-n obtained by adding together a shift-processed sound signal X'-n and the original, non-shift-processed sound signal X-n.

Masking sound generating apparatus, storage medium stored with masking sound signal, masking sound reproducing apparatus, and program

In a masker sound generation apparatus, an acquisition part acquires a sound signal, and a generation part generates a masker sound signal based on the acquired sound signal. Specifically, the generation part divides the sound signal acquired by the acquisition part into a plurality of sections each having a predetermined time length, then repeats a sorting process of sorting the divided sections as a process of changing the sequence of arrangement of the sound signal, and alters a manner of sorting the sections each time the sorting process is repeated.

Masker sound generation apparatus and program

A speaker array apparatus capable of performing directivity control with ease even when sound emission is performed based on audio signals of different frequency ranges. The speaker array apparatus includes a speaker unit for emitting high-frequency range sound, and another speaker unit for emitting low- and high-frequency range sound. A signal processed by a high pass filter is used for generation of both audio signals used by these speaker units to emit the high-frequency range sounds. Since both the audio signals are rotated in phase similarly to each other, the phases of audio signals supplied to both the speaker units are in coincidence with each other in high-frequency range, which makes it easy to carry out directivity control.

Speaker array apparatus and signal processing method therefor

A delay time calculation apparatus enabling all the speaker units of a delay array type speaker array to contribute to formation of a combined wavefront. Sound receiving points for acoustic waves output from the speaker units are set within a target area for the acoustic waves. For each speaker unit, an average value of differences between distances between the sound receiving points for the speaker units and other speaker units and distances between the sound receiving points for the speaker units and the speaker units is determined, and an average value of differences between distances from the other speaker units to sound receiving points for the other speaker units and distances from the speaker units to the sound receiving points for the other speaker units is determined. An average of the average values is converted into a delay time, thereby determining the delay time for each speaker unit.

Delay time calculation apparatus and method

A delay time calculation apparatus that enables all of speaker units constituting a speaker array to contribute to the formation of a combined wavefront directed to an area specified by a user. The delay time calculation apparatus includes a delay time calculation unit that calculates delay times of delayed audio signals supplied to the speaker units such that a ratio at which an evaluation object area is occupied by an area to which an acoustic wave output from each speaker unit reaches earlier than acoustic waves output from the other speaker units falls within a predetermined range. The evaluation object area is a target area to which a combined wavefront of acoustic waves output from the speaker units is directed, or is a perspective projection image of the target area onto a predetermined evaluation plane.

Delay time calculation apparatus, delay time calculation method, and storage medium storing program therefor

A speaker array system for outputting, with a simplified construction, sounds audible with a nearly uniform sound volume within an arbitrarily set area. The speaker array system includes a speaker array having speaker units, a delay unit for supplying the speaker units with delayed audio signals generated by adding delays to an input audio signal, an input unit for inputting area information representing a target area to which an acoustic service is provided using an acoustic beam emitted from the speaker array and which has a normal line extending in a direction different from a normal direction of a speaker surface of the speaker array, and a control unit for calculating delays to be applied to the delay unit. Based on the delays, acoustic waves output from adjacent ones of the speaker units toward the target area are made coincident with each other and an envelope is more distorted from a spherical surface so as to face the target area as the envelope propagates closer to the target area.

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Iwata, Japan

Takashi Yamakawa