公开(公告)号：US20230410832A1

公开(公告)日：2023-12-21

申请号：US18033025

申请日：2020-11-05

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Ryosuke SUGIURA ,  Takehiro MORIYA ,  Yutaka KAMAMOTO

IPC: G10L21/0388 ,  G10L19/008

CPC classification number: G10L21/0388 ,  G10L19/008

Abstract: For each frame, an n-th channel compensated decoded sound signal {tilde over ( )}X′n is obtained that is a signal obtained by compensating a high frequency of an n-th channel purified decoded sound signal {tilde over ( )}Xn obtained by performing signal processing in a time domain on an n-th channel decoded sound signal {circumflex over ( )}Xn that is a decoded sound signal of each channel of stereo obtained by decoding a stereo code CS. At this time, for the each frame with respect to the each channel, an n-th channel high-frequency compensation gain ρn that is a value for bringing high-frequency energy of {tilde over ( )}X′n close to high-frequency energy of {circumflex over ( )}Xn is obtained, and for the each frame with respect to the each channel, a signal obtained by adding {tilde over ( )}Xn and a signal obtained by multiplying a high-frequency component of a monaural decoded sound signal that is obtained by decoding a monaural code CM that is a code different from the stereo code CS or a signal obtained by upmixing, for the each channel, the monaural decoded sound signal by the n-th channel high-frequency compensation gain ρn is obtained and output as the n-th channel compensated decoded sound signal {tilde over ( )}X′n.

公开(公告)号：US20230386480A1

公开(公告)日：2023-11-30

申请号：US18031588

申请日：2020-11-05

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Ryosuke SUGIURA ,  Takehiro MORIYA ,  Yutaka KAMAMOTO

IPC: G10L19/008

CPC classification number: G10L19/008

Abstract: There is provided a technology that improves, in a case where there is a sound signal obtained from a different code that is different from a code from which a decoded sound signal is obtained and that is derived from the same sound signal, the decoded sound signal by using the sound signal obtained from the different code. A signal (hereinafter, referred to as an upmixed common signal) obtained by upmixing a decoded sound common signal obtained by downmixing a decoded sound signal of each channel is subjected to signal purification using a signal (hereinafter, referred to as an upmixed monaural decoded sound signal) obtained by upmixing a monaural decoded sound signal to thereby generate a purified upmixed signal, and in each channel, the upmixed common signal is subtracted from the decoded sound signal and the purified upmixed signal is added thereto, to thereby generate a purified decoded sound signal.

公开(公告)号：US20230288247A1

公开(公告)日：2023-09-14

申请号：US18017025

申请日：2020-07-28

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Kenji ISHIKAWA ,  Yoshifumi SHIRAKI ,  Takehiro MORIYA ,  Kenichi HITACHI ,  Atsushi ISHIZAWA ,  Katsuya OGURI

IPC: G01H9/00 ,  G01B9/02001 ,  H04R23/00

CPC classification number: G01H9/00 ,  G01B9/0201 ,  H04R23/008

Abstract: An optical phase modulation amount measurement technology using sound without being affected by noise included in an average light intensity is provided. A sound measurement method includes an interference light generation step of obtaining first light including light subjected to light phase modulation by a sound measurement unit and second light including light subjected to light phase modulation by the sound measurement unit, which differs from the first light, from light emitted from a light source, a first light detection step of obtaining a first electrical signal from the first light, a second light detection step of obtaining a second electrical signal from the second light, and a differential signal generation step of obtaining a differential signal that is a difference between the first electrical signal and the second electrical signal, wherein a phase of the light subjected to light phase modulation included in the first light and a phase of the light subjected to the light phase modulation included in the second light are in an inverted relationship, and an optical phase modulation amount φs by sound is measured as a current Δi of the differential signal expressed by an equation Δi=βIA cos (φs+φ0) (where β is a predetermined constant, IA is an amplitude of an interference fringe, and φ0 is an optical phase modulation amount by an element other than sound).

公开(公告)号：US20210335375A1

公开(公告)日：2021-10-28

申请号：US17370060

申请日：2021-07-08

Applicant: Nippon Telegraph and Telephone Corporation

Inventor： Takehiro MORIYA ,  Yutaka KAMAMOTO ,  Noboru HARADA

IPC: G10L19/07 ,  G10L19/038

Abstract: A coding method and a decoding method are provided which can use in combination a predictive coding and decoding method which is a coding and decoding method that can accurately express coefficients which are convertible into linear prediction coefficients with a small code amount and a coding and decoding method that can obtain correctly, by decoding, coefficients which are convertible into linear prediction coefficients of the present frame if a linear prediction coefficient code of the present frame is correctly input to a decoding device. A coding device includes: a predictive coding unit that obtains a first code by coding a differential vector formed of differentials between a vector of coefficients which are convertible into linear prediction coefficients of more than one order of the present frame and a prediction vector containing at least a predicted vector from a past frame, and obtains a quantization differential vector corresponding to the first code; and a non-predictive coding unit that generates a second code by coding a correction vector which is formed of differentials between the vector of the coefficients which are convertible into the linear prediction coefficients of more than one order of the present frame and the quantization differential vector or formed of some of elements of the differentials.

公开(公告)号：US20210233549A1

公开(公告)日：2021-07-29

申请号：US17053681

申请日：2019-03-22

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Yutaka KAMAMOTO ,  Ryosuke SUGIURA ,  Takehiro MORIYA

IPC: G10L21/013 ,  G10L21/034 ,  G10L21/0364

Abstract: As pitch enhancement processing, a pitch enhancement apparatus obtains, for a time segment judged to be a time segment including a signal that is a consonant, for each time of the time segment, as an output signal, a signal including a signal obtained by adding a signal, which was obtained by multiplying a signal at a time that is an earlier time than the time by the number of samples T0 corresponding to a pitch period of the time segment, the pitch gain σ0 of the time segment, a predetermined constant B0, and a value that is greater than 0 and less than 1, and a signal at the time.

公开(公告)号：US20210090587A1

公开(公告)日：2021-03-25

申请号：US17053698

申请日：2019-04-23

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Yutaka KAMAMOTO ,  Ryosuke SUGIURA ,  Takehiro MORIYA

IPC: G10L21/0364 ,  G10L25/90 ,  G10L21/0332

Abstract: Provided is pitch enhancement processing having little unnaturalness even in time segments for consonants, and having little unnaturalness to listeners caused by discontinuities even when time segments for consonants and other time segments switch frequently. A pitch emphasis apparatus carries out the following as the pitch enhancement processing: for a time segment in which a spectral envelope of a signal has been determined to be flat, obtaining an output signal for each of times in the time segment, the output signal being a signal including a signal obtained by adding (1) a signal obtained by multiplying the signal of a time, further in the past than the time by a number of samples T0 corresponding to a pitch period of the time segment, a pitch gain σ0 of the time segment, a predetermined constant B0, and a value greater than 0 and less than 1, to (2) the signal of the time.

公开(公告)号：US20200162102A1

公开(公告)日：2020-05-21

申请号：US16618567

申请日：2018-04-20

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Ryosuke SUGIURA ,  Yutaka KAMAMOTO ,  Takehiro MORIYA ,  Noboru HARADA

IPC: H03M7/40

Abstract: An encoding/decoding technique is provided with which encoding can be performed using a small average number of bits even for a sequence of integer values including small non-zero values and having a distribution heavily biased toward small values. The present invention includes an integer encoding part 110 that, with respect to an inputted sequence of non-negative integer values x_n, n∈ {1, 2, . . . , N} (hereinafter referred to as an “integer sequence”), obtains a 1-bit code as a code corresponding to a run of integer values 0 of length L, a predetermined number which satisfies 2≤L≤2K−1, which is included in the integer sequence and obtains a (K×x_n)-bit or (K×x_n+1)-bit code as a code corresponding to a set of a run of integer values 0 of length from 0 to L−1 and one non-zero integer value x_n included in the integer sequence, where K is assumed to be an integer equal to or larger than 2.

公开(公告)号：US20200090664A1

公开(公告)日：2020-03-19

申请号：US16687144

申请日：2019-11-18

Applicant: Nippon Telegraph and Telephone Corporation

Inventor： Takehiro MORIYA ,  Noboru Harada ,  Yutaka Kamamoto ,  Yusuke Hiwasaki ,  Masahiro Fukui

IPC: G10L19/005 ,  G10L19/032 ,  G10L19/24 ,  G10L19/008 ,  G10L21/038 ,  G10L19/16

Abstract: In encoding, a frequency-domain sample sequence derived from an acoustic signal is divided by a weighted envelope and is then divided by a gain, the result obtained is quantized, and each sample is variable-length encoded. The error between the sample before quantization and the sample after quantization is quantized with information saved in this variable-length encoding. This quantization is performed under a rule that specifies, according to the number of saved bits, samples whose errors are to be quantized. In decoding, variable-length codes in an input sequence of codes are decoded to obtain a frequency-domain sample sequence; an error signal is further decoded under a rule that depends on the number of bits of the variable-length codes; and from the obtained sample sequence, the original sample sequence is obtained according to supplementary information.

公开(公告)号：US20190304476A1

公开(公告)日：2019-10-03

申请号：US16429590

申请日：2019-06-03

Applicant: Nippon Telegraph and Telephone Corporation

Inventor： Takehiro MORIYA ,  Yutaka KAMAMOTO ,  Noboru HARADA

IPC: G10L19/07 ,  G10L19/06 ,  G10L19/032

Abstract: A technology of accurately coding and decoding coefficients which are convertible into linear prediction coefficients even for a frame in which the spectrum variation is great while suppressing an increase in the code amount as a whole is provided. A coding device includes: a first coding unit that obtains a first code by coding coefficients which are convertible into linear prediction coefficients of more than one order; and a second coding unit that obtains a second code by coding at least quantization errors of the first coding unit if (A-1) an index Q commensurate with how high the peak-to-valley height of a spectral envelope is, the spectral envelope corresponding to the coefficients which are convertible into the linear prediction coefficients of more than one order, is larger than or equal to a predetermined threshold value Th1 and/or (B-1) an index Q′ commensurate with how short the peak-to-valley height of the spectral envelope is, is smaller than or equal to a predetermined threshold value Th1′.

公开(公告)号：US20180294881A1

公开(公告)日：2018-10-11

申请号：US15574319

申请日：2016-04-07

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Naotaka SHIBATA ,  Shigeru KUWANO ,  Yutaka KAMAMOTO ,  Takehiro MORIYA ,  Jun TERADA

IPC: H04B10/2575 ,  H04L29/06

Abstract: An optical communication system includes a signal processing apparatus and a wireless apparatus between which functions of a base station are divided, wherein a periodic symbol sequence including a cyclic prefix appended to a signal of a predetermined size to which an IFFT (Inverse Fast Fourier Transform) has been applied is transmitted between the signal processing apparatus and the wireless apparatus by means of digital RoF (Radio over Fiber) transmission, the signal processing apparatus and the wireless apparatus each include a transmission unit and a reception unit, the transmission unit includes: a compression size determination unit that acquires symbol information relating to a starting position of the symbol sequence and lengths of symbols constituting the symbol sequence, and that determines, based on the acquired symbol information, a compression size for each of symbols that are to be compressed; and a compression unit that compresses the symbol sequence in units of determined compression sizes, and the reception unit includes: an expansion size determination unit that determines an expansion size for each of symbols in the symbol sequence that are to be expanded; and an expansion unit that expands the symbol sequence in units of determined expansion sizes.