公开(公告)号：US20220312095A1

公开(公告)日：2022-09-29

申请号：US17638811

申请日：2019-09-02

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Sakurako YAZAWA ,  Kazunori KOBAYASHI ,  Kenichi NOGUCHI

IPC: H04R1/08 ,  H04R1/40

Abstract: A microphone array is a microphone array including two or more microphone holders 1. The two or more microphone holders 1 each hold one microphone. The two or more microphone holders 1 are separatable from each other. The two or more microphone holders 1 are combinable in two or more combination manners different from each other such that the two or more microphone holders 1 are each in contact with any one of the other microphone holders 1 and a distance between the two respective microphones held by two of the microphone holders 1 that are in contact with each other is a predetermined distance.

公开(公告)号：US20210006892A1

公开(公告)日：2021-01-07

申请号：US16977002

申请日：2019-02-28

Applicant: Nippon Telegraph and Telephone Corporation

Inventor： Kimitaka TSUTSUMI ,  Kenichi NOGUCHI ,  Hideaki TAKADA ,  Yoichi HANEDA

IPC: H04R1/40 ,  H04R3/12

Abstract: An acoustic signal processing device 1 includes: a focal point position determination unit 12 that obtains a plurality of sets of initial focal point coordinates, coordinates of the virtual sound source, and a direction of directivity thereof, and for a pair of sets of initial focal point coordinates with different polarities among the plurality of sets of initial focal point coordinates, multiplies the sets of initial focal point coordinates by a rotation matrix based on the coordinates of the virtual sound source to thereby determine sets of focal point coordinates, the rotation matrix being specified from the direction of the directivity; a circular harmonic coefficient conversion unit 13 that calculates weights to be applied to multipoles including the sets of focal point coordinates from a circular harmonic coefficient; a filter coefficient computation unit 14 that, for each of the speakers in the speaker array, computes a weighted driving function to be applied to the speaker from the sets of focal point coordinates, polarities of the sets of focal point coordinates, and the weights to be applied to the multipoles; and a convolutional operation unit 15 that, for each of the speakers in the speaker array, convolves the weighted driving function for the speaker into the input acoustic signal to output the output acoustic signal for the speaker.

公开(公告)号：US20210335372A1

公开(公告)日：2021-10-28

申请号：US16332583

申请日：2017-09-13

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Ryosuke SUGIURA ,  Takehiro MORIYA ,  Noboru HARADA ,  Takahito KAWANISHI ,  Yutaka KAMAMOTO ,  Kouichi FURUKADO ,  Junichi NAKAJIMA ,  Jouji NAKAYAMA ,  Kenichi NOGUCHI ,  Keisuke HASEGAWA

IPC: G10L19/035 ,  G10L19/00

Abstract: Performance of an encoding process and a decoding process for a sound signal is enhanced. A representative value calculating part 110 calculates, for each frequency section by a plurality of samples fewer than the number of frequency samples of a sample sequence of a frequency domain signal corresponding to an input acoustic signal, from the sample sequence of the frequency domain signal, a representative value of the frequency section from sample values of samples included in the frequency section, for each of predetermined time sections. A signal companding part 120 obtains, for each of the predetermined time sections, a frequency domain sample sequence obtained by multiplying a weight according to a function value of the representative value by a companding function for which an inverse function can be defined and each of the samples corresponding to the representative value in the sample sequence of the frequency domain signal, as a sample sequence of a weighted frequency domain signal.

公开(公告)号：US20210105571A1

公开(公告)日：2021-04-08

申请号：US17050102

申请日：2019-04-15

Applicant: Nippon Telegraph and Telephone Corporation

Inventor： Kimitaka TSUTSUMI ,  Kenichi NOGUCHI ,  Hideaki TAKADA ,  Yoichi HANEDA

IPC: H04S7/00 ,  H04R3/12 ,  H04R5/04 ,  H04R5/02

Abstract: Provided is a sound image reproduction device, sound image reproduction method, and sound image reproduction program that can support monaural sound sources and is capable of imparting directivity to virtual sound sources in a space. An acoustic signal processing device (sound image reproduction device) 1 that generates virtual sound sources in a space using multiple loudspeakers arranged in a straight line, includes: a focal-point position determination unit 12 that determines the position of each virtual sound source to generate multiple virtual sound sources in a circular arrangement; a filter-coefficient determination unit 13 that calculates an impulse response vector for each loudspeaker by performing an inverse Fourier transform on a driving function for each loudspeaker that is used to generate a virtual sound source at the position of each virtual sound source and in which different weights are given to some of the virtual sound sources; and a convolution calculation unit 14 that calculates the convolution of one inputted acoustic signal with the impulse response vector for each loudspeaker and outputs each acoustic signal to the corresponding the multiple loudspeakers.

公开(公告)号：US20240245882A1

公开(公告)日：2024-07-25

申请号：US18681017

申请日：2021-08-04

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Hiroaki ITO ,  Hironobu CHIBA ,  Tatsuya KAKO ,  Kenichi NOGUCHI

IPC: A61M21/02 ,  A61M21/00 ,  H04S1/00 ,  H04S7/00

CPC classification number: A61M21/02 ,  H04S1/007 ,  H04S7/307 ,  A61M2021/0027 ,  H04S2400/15

Abstract: The signal processing device includes: a beat sound frequency determination unit that determines an optimal beat sound frequency of a user on the basis of a brain wave signal of the user; and a binaural beat signal generation unit that acquires an ambient environment sound, converts a sample acoustic signal prepared in advance into a binaural beat, on the basis of an optimal beat sound frequency, and mixes the binaural-beat-converted sample acoustic signal with the ambient environment sound, to generate a binaural-beat-converted ambient environmental sound signal.

公开(公告)号：US20210321192A1

公开(公告)日：2021-10-14

申请号：US17265673

申请日：2019-07-25

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Sakurako YAZAWA ,  Kazunori KOBAYASHI ,  Kenichi NOGUCHI ,  Shoichiro SAITO

IPC: H04R1/40

Abstract: Provided is a sound collection apparatus, including: a substantially spherical base on which at least N recess portions are provided in a surface thereof with a predetermined interval therebetween; and N microphones. N is an integer of 2 or greater. The microphones are installed on an inner bottom surface side of the recess portions one by one. Intervals between sound collecting portions of adjacent microphones are substantially equal to each other.