Patents by Inventor Masakiyo Fujimoto

Masakiyo Fujimoto 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).

  • Audio signal section estimating apparatus, audio signal section estimating method, and recording medium
    Patent number: 9208780
    Abstract: The processing efficiency and estimation accuracy of a voice activity detection apparatus are improved. An acoustic signal analyzer receives a digital acoustic signal containing a speech signal and a noise signal, generates a non-speech GMM and a speech GMM adapted to a noise environment, by using a silence GMM and a clean-speech GMM in each frame of the digital acoustic signal, and calculates the output probabilities of dominant Gaussian distributions of the GMMs. A speech state probability to non-speech state probability ratio calculator calculates a speech state probability to non-speech state probability ratio based on a state transition model of a speech state and a non-speech state, by using the output probabilities; and a voice activity detection unit judges, from the speech state probability to non-speech state probability ratio, whether the acoustic signal in the frame is in the speech state or in the non-speech state and outputs only the acoustic signal in the speech state.
    Type: Grant
    Filed: July 15, 2010
    Date of Patent: December 8, 2015
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Masakiyo Fujimoto, Tomohiro Nakatani
  • VOICE ACTIVITY DETECTION APPARATUS, VOICE ACTIVITY DETECTION METHOD, PROGRAM THEREOF, AND RECORDING MEDIUM
    Publication number: 20120173234
    Abstract: The processing efficiency and estimation accuracy of a voice activity detection apparatus are improved. An acoustic signal analyzer receives a digital acoustic signal containing a speech signal and a noise signal, generates a non-speech GMM and a speech GMM adapted to a noise environment, by using a silence GMM and a clean-speech GMM in each frame of the digital acoustic signal, and calculates the output probabilities of dominant Gaussian distributions of the GMMs. A speech state probability to non-speech state probability ratio calculator calculates a speech state probability to non-speech state probability ratio based on a state transition model of a speech state and a non-speech state, by using the output probabilities; and a voice activity detection unit judges, from the speech state probability to non-speech state probability ratio, whether the acoustic signal in the frame is in the speech state or in the non-speech state and outputs only the acoustic signal in the speech state.
    Type: Application
    Filed: July 15, 2010
    Publication date: July 5, 2012
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORP.
    Inventors: Masakiyo Fujimoto, Tomohiro Nakatani