Patents by Inventor Kei Kikuiri

Kei Kikuiri has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20230410795
    Abstract: The related information presentation server 10 includes an acquisition unit 12 configured to acquire presentation information indicating lecture content by a lecturer, a detection unit 13 configured to detect a pre-registered keyword included in the presentation information acquired by the acquisition unit 12, and a presentation unit 14 configured to present related information related to the keyword detected by the detection unit 13 to a student. The presentation unit 14 is configured to determine a frequency of presenting the related information to the student based on at least one of a knowledge level of the student regarding the presentation content and a degree of difficulty of the keyword, and present the related information to the student in accordance with the determined frequency.
    Type: Application
    Filed: December 8, 2021
    Publication date: December 21, 2023
    Applicant: NTT DOCOMO, INC.
    Inventors: Mariko CHIBA, Junya TAKIUE, Sae IIJIMA, Taichi KATAYAMA, Kei KIKUIRI
  • Patent number: 11756556
    Abstract: An audio packet error concealment system includes an encoding unit for encoding an audio signal consisting of a plurality of frames, and an auxiliary information encoding unit for estimating and encoding auxiliary information about a temporal change of power of the audio signal. The auxiliary information is used in packet loss concealment in decoding of the audio signal. The auxiliary information about the temporal change of power may contain a parameter that functionally approximates a plurality of powers of subframes shorter than one frame, or may contain information about a vector obtained by vector quantization of a plurality of powers of subframes shorter than one frame.
    Type: Grant
    Filed: March 23, 2022
    Date of Patent: September 12, 2023
    Assignees: NTT DOCOMO, INC., JPMORGAN CHASE BANK, N.A., AS COLLATERAL AGENT
    Inventors: Kimitaka Tsutsumi, Kei Kikuiri
  • Patent number: 11749291
    Abstract: An audio signal processing system and method is executed by an audio signal processing device to decode an audio packet to obtain decoded audio and determine an occurrence of a discontinuity occurring with a sudden increase of an amplitude of the decoded audio obtained by decoding the audio packet. The audio packet may be received correctly after an occurrence of a packet loss, and corrected to improve subjective quality of the decoded audio, wherein correcting the discontinuity of the decoded audio comprises causing distances between ISF/LSF parameters corresponding to a frame in which a packet loss has occurred to be equal.
    Type: Grant
    Filed: January 13, 2022
    Date of Patent: September 5, 2023
    Assignee: NTT DOCOMO, INC.
    Inventors: Kimitaka Tsutsumi, Kei Kikuiri, Atsushi Yamaguchi
  • Patent number: 11749292
    Abstract: An audio signal transmission device for encoding an audio signal includes an audio encoding unit that encodes an audio signal and a side information encoding unit that calculates and encodes side information from a look-ahead signal. An audio signal receiving device for decoding an audio code and outputting an audio signal includes: an audio code buffer that detects packet loss based on a received state of an audio packet, an audio parameter decoding unit that decodes an audio code when an audio packet is correctly received, a side information decoding unit that decodes a side information code when an audio packet is correctly received, a side information accumulation unit that accumulates side information obtained by decoding a side information code, an audio parameter missing processing unit that outputs an audio parameter upon detection of audio packet loss, and an audio synthesis unit that synthesizes decoded audio from the audio parameter.
    Type: Grant
    Filed: November 1, 2021
    Date of Patent: September 5, 2023
    Assignee: NTT DOCOMO, INC.
    Inventors: Kimitaka Tsutsumi, Kei Kikuiri, Atsushi Yamaguchi
  • Patent number: 11562760
    Abstract: An objective of the present invention is to correct a temporal envelope shape of a decoded signal with a small information volume and to reduce perceptible distortions.
    Type: Grant
    Filed: June 5, 2020
    Date of Patent: January 24, 2023
    Assignee: NTT DOCOMO, INC.
    Inventors: Kei Kikuiri, Atsushi Yamaguchi
  • Publication number: 20220366924
    Abstract: The purpose of the present invention is to reduce distortion a frequency band component encoded with a small number of bits in a time domain and improve quality. An audio decoding device (10) decodes an encoded audio signal and outputs the audio signal. A decoding unit (10a) decodes an encoded sequence containing an encoded audio signal and obtains a decoded signal. A selective temporal envelope shaping unit (10b) shapes a temporal envelope of a decoded signal in the frequency band on the basis of decoding related information concerning decoding of the encoded sequence.
    Type: Application
    Filed: July 27, 2022
    Publication date: November 17, 2022
    Applicant: NTT DOCOMO, INC.
    Inventors: Kei Kikuiri, Atsushi Yamaguchi
  • Patent number: 11437053
    Abstract: The purpose of the present invention is to reduce distortion a frequency band component encoded with a small number of bits in a time domain and improve quality. An audio decoding device (10) decodes an encoded audio signal and outputs the audio signal. A decoding unit (10a) decodes an encoded sequence containing an encoded audio signal and obtains a decoded signal. A selective temporal envelope shaping unit (10b) shapes a temporal envelope of a decoded signal in the frequency band on the basis of decoding related information concerning decoding of the encoded sequence.
    Type: Grant
    Filed: July 31, 2019
    Date of Patent: September 6, 2022
    Assignee: NTT DOCOMO, INC.
    Inventors: Kei Kikuiri, Atsushi Yamaguchi
  • Publication number: 20220215846
    Abstract: An audio packet error concealment system includes an encoding unit for encoding an audio signal consisting of a plurality of frames, and an auxiliary information encoding unit for estimating and encoding auxiliary information about a temporal change of power of the audio signal. The auxiliary information is used in packet loss concealment in decoding of the audio signal. The auxiliary information about the temporal change of power may contain a parameter that functionally approximates a plurality of powers of subframes shorter than one frame, or may contain information about a vector obtained by vector quantization of a plurality of powers of subframes shorter than one frame.
    Type: Application
    Filed: March 23, 2022
    Publication date: July 7, 2022
    Applicant: NTT DOCOMO, INC.
    Inventors: Kimitaka Tsutsumi, Kei Kikuiri
  • Publication number: 20220139411
    Abstract: An audio signal processing device comprises a discontinuity detector configured to determine an occurrence of a discontinuity from a sudden increase of an amplitude of decoded audio obtained by decoding the first audio packet which is received correctly after an occurrence of a packet loss, and a discontinuity corrector for correcting the discontinuity of the decoded audio.
    Type: Application
    Filed: January 13, 2022
    Publication date: May 5, 2022
    Applicant: NTT DOCOMO, INC.
    Inventors: Kimitaka Tsutsumi, Kei Kikuiri, Atsushi Yamaguchi
  • Patent number: 11322163
    Abstract: An audio packet error concealment system includes an encoding unit for encoding an audio signal consisting of a plurality of frames, and an auxiliary information encoding unit for estimating and encoding auxiliary information about a temporal change of power of the audio signal. The auxiliary information is used in packet loss concealment in decoding of the audio signal. The auxiliary information about the temporal change of power may contain a parameter that functionally approximates a plurality of powers of subframes shorter than one frame, or may contain information about a vector obtained by vector quantization of a plurality of powers of subframes shorter than one frame.
    Type: Grant
    Filed: July 23, 2020
    Date of Patent: May 3, 2022
    Assignee: NTT DOCOMO, INC.
    Inventors: Kimitaka Tsutsumi, Kei Kikuiri
  • Patent number: 11270715
    Abstract: An audio signal processing device comprises a discontinuity detector configured to determine an occurrence of a discontinuity from a sudden increase of an amplitude of decoded audio obtained by decoding the first audio packet which is received correctly after an occurrence of a packet loss, and a discontinuity corrector for correcting the discontinuity of the decoded audio by changing, in a state buffer, a distance between elements of Immittance Spectral Pair/Immittance Spectral Frequency (ISF/LSF) parameters of a past frame.
    Type: Grant
    Filed: April 9, 2020
    Date of Patent: March 8, 2022
    Assignee: NTT DOCOMO, INC.
    Inventors: Kimitaka Tsutsumi, Kei Kikuiri, Atsushi Yamaguchi
  • Publication number: 20220059108
    Abstract: An audio signal transmission device for encoding an audio signal includes an audio encoding unit that encodes an audio signal and a side information encoding unit that calculates and encodes side information from a look-ahead signal. An audio signal receiving device for decoding an audio code and outputting an audio signal includes: an audio code buffer that detects packet loss based on a received state of an audio packet, an audio parameter decoding unit that decodes an audio code when an audio packet is correctly received, a side information decoding unit that decodes a side information code when an audio packet is correctly received, a side information accumulation unit that accumulates side information obtained by decoding a side information code, an audio parameter missing processing unit that outputs an audio parameter upon detection of audio packet loss, and an audio synthesis unit that synthesizes decoded audio from the audio parameter.
    Type: Application
    Filed: November 1, 2021
    Publication date: February 24, 2022
    Applicant: NTT DOCOMO, INC.
    Inventors: Kimitaka Tsutsumi, Kei Kikuiri, Atsushi Yamaguchi
  • Patent number: 11211077
    Abstract: An audio signal transmission device for encoding an audio signal includes an audio encoding unit that encodes an audio signal and a side information encoding unit that calculates and encodes side information from a look-ahead signal. An audio signal receiving device for decoding an audio code and outputting an audio signal includes: an audio code buffer that detects packet loss based on a received state of an audio packet, an audio parameter decoding unit that decodes an audio code when an audio packet is correctly received, a side information decoding unit that decodes a side information code when an audio packet is correctly received, a side information accumulation unit that accumulates side information obtained by decoding a side information code, an audio parameter missing processing unit that outputs an audio parameter upon detection of audio packet loss, and an audio synthesis unit that synthesizes decoded audio from the audio parameter.
    Type: Grant
    Filed: December 17, 2019
    Date of Patent: December 28, 2021
    Assignee: NTT DOCOMO, INC.
    Inventors: Kimitaka Tsutsumi, Kei Kikuiri, Atsushi Yamaguchi
  • Patent number: 11195538
    Abstract: An audio signal transmission device for encoding an audio signal includes an audio encoding unit that encodes an audio signal and a side information encoding unit that calculates and encodes side information from a look-ahead signal. An audio signal receiving device for decoding an audio code and outputting an audio signal includes: an audio code buffer that detects packet loss based on a received state of an audio packet, an audio parameter decoding unit that decodes an audio code when an audio packet is correctly received, a side information decoding unit that decodes a side information code when an audio packet is correctly received, a side information accumulation unit that accumulates side information obtained by decoding a side information code, an audio parameter missing processing unit that outputs an audio parameter upon detection of audio packet loss, and an audio synthesis unit that synthesizes decoded audio from the audio parameter.
    Type: Grant
    Filed: December 17, 2019
    Date of Patent: December 7, 2021
    Assignee: NTT DOCOMO, INC.
    Inventors: Kimitaka Tsutsumi, Kei Kikuiri, Atsushi Yamaguchi
  • Patent number: 11176955
    Abstract: An audio signal transmission device for encoding an audio signal includes an audio encoding unit that encodes an audio signal and a side information encoding unit that calculates and encodes side information from a look-ahead signal. An audio signal receiving device for decoding an audio code and outputting an audio signal includes: an audio code buffer that detects packet loss based on a received state of an audio packet, an audio parameter decoding unit that decodes an audio code when an audio packet is correctly received, a side information decoding unit that decodes a side information code when an audio packet is correctly received, a side information accumulation unit that accumulates side information obtained by decoding a side information code, an audio parameter missing processing unit that outputs an audio parameter upon detection of audio packet loss, and an audio synthesis unit that synthesizes decoded audio from the audio parameter.
    Type: Grant
    Filed: December 17, 2019
    Date of Patent: November 16, 2021
    Assignee: NTT DOCOMO, INC.
    Inventors: Kimitaka Tsutsumi, Kei Kikuiri, Atsushi Yamaguchi
  • Patent number: 11158331
    Abstract: An audio signal transmission device for encoding an audio signal includes an audio encoding unit that encodes an audio signal and a side information encoding unit that calculates and encodes side information from a look-ahead signal. An audio signal receiving device for decoding an audio code and outputting an audio signal includes: an audio code buffer that detects packet loss based on a received state of an audio packet, an audio parameter decoding unit that decodes an audio code when an audio packet is correctly received, a side information decoding unit that decodes a side information code when an audio packet is correctly received, a side information accumulation unit that accumulates side information obtained by decoding a side information code, an audio parameter missing processing unit that outputs an audio parameter upon detection of audio packet loss, and an audio synthesis unit that synthesizes decoded audio from the audio parameter.
    Type: Grant
    Filed: December 17, 2019
    Date of Patent: October 26, 2021
    Assignee: NTT DOCOMO, INC.
    Inventors: Kimitaka Tsutsumi, Kei Kikuiri, Atsushi Yamaguchi
  • Publication number: 20200357416
    Abstract: An audio packet error concealment system includes an encoding unit for encoding an audio signal consisting of a plurality of frames, and an auxiliary information encoding unit for estimating and encoding auxiliary information about a temporal change of power of the audio signal. The auxiliary information is used in packet loss concealment in decoding of the audio signal. The auxiliary information about the temporal change of power may contain a parameter that functionally approximates a plurality of powers of subframes shorter than one frame, or may contain information about a vector obtained by vector quantization of a plurality of powers of subframes shorter than one frame.
    Type: Application
    Filed: July 23, 2020
    Publication date: November 12, 2020
    Applicant: NTT DOCOMO, INC.
    Inventors: Kimitaka Tsutsumi, Kei Kikuiri
  • Publication number: 20200302945
    Abstract: An objective of the present invention is to correct a temporal envelope shape of a decoded signal with a small information volume and to reduce perceptible distortions.
    Type: Application
    Filed: June 5, 2020
    Publication date: September 24, 2020
    Applicant: NTT DOCOMO, INC.
    Inventors: Kei Kikuiri, Atsushi Yamaguchi
  • Patent number: 10762908
    Abstract: An audio packet error concealment system includes an encoding unit for encoding an audio signal consisting of a plurality of frames, and an auxiliary information encoding unit for estimating and encoding auxiliary information about a temporal change of power of the audio signal. The auxiliary information is used in packet loss concealment in decoding of the audio signal. The auxiliary information about the temporal change of power may contain a parameter that functionally approximates a plurality of powers of subframes shorter than one frame, or may contain information about a vector obtained by vector quantization of a plurality of powers of subframes shorter than one frame.
    Type: Grant
    Filed: September 20, 2018
    Date of Patent: September 1, 2020
    Assignee: NTT DOCOMO, INC.
    Inventors: Kimitaka Tsutsumi, Kei Kikuiri
  • Publication number: 20200234723
    Abstract: An audio signal processing device comprises a discontinuity detector configured to determine an occurrence of a discontinuity from a sudden increase of an amplitude of decoded audio obtained by decoding the first audio packet which is received correctly after an occurrence of a packet loss, and a discontinuity corrector for correcting the discontinuity of the decoded audio.
    Type: Application
    Filed: April 9, 2020
    Publication date: July 23, 2020
    Applicant: NTT DOCOMO, INC.
    Inventors: Kimitaka Tsutsumi, Kei Kikuiri, Atsushi Yamaguchi