Patents by Inventor Tomofumi Nakatani

Tomofumi Nakatani 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).

  • Patent number: 5347612
    Abstract: After sampling a voice signal by a microphone (31), a voice interval is detected by a voice interval detector (32). Then, the voice signal is processed by a frequency analyzer (33) having a predetermined number of channels at a predetermined time interval, whereby a corresponding portion of the voice signal is quantized at each channel. Then, quantized data obtained from these channels are binary converted (34) to thereby form a frame comprised of a series of binary data. Each data of this frame corresponds to one of the channels, and preferably it is set to be an integral multiple of a computer calculation unit (e.g., 4 bits, 8 bits, etc.). When forming a combination frame by superimposing two or more of such frames, the combination frame is divided into layers, whereby it is so structured that each bit is represented by a binary number in each layer.
    Type: Grant
    Filed: July 16, 1990
    Date of Patent: September 13, 1994
    Assignee: Ricoh Company, Ltd.
    Inventors: Junichiroh Fujimoto, Seigo Yasuda, Tomofumi Nakatani
  • Patent number: 5150413
    Abstract: When subjected to frequency analysis and plotted in a frequency spectral distribution, a voice signal typically includes a monotonously and relatively slowly changing component and a relatively rapidly changing component. For the recognition of voice sound, the relatively rapidly changing component contains phonemic information and thus is more important. In order to extract such a relatively rapidly changing component containing phonemic information from a voice signal, the voice signal is first subjected to frequency analysis to obtain a frequency spectral distribution, which is then sampled from one end to the other and then in the reversed order in timed sequence repetitively to produce a periodic waveform. Then, the thus obtained periodic waveform is filtered to remove the relatively slowly changing component thereby extracting the relatively rapidly changing component.
    Type: Grant
    Filed: October 2, 1989
    Date of Patent: September 22, 1992
    Assignee: Ricoh Company, Ltd.
    Inventors: Tomofumi Nakatani, Shogo Nakamura
  • Patent number: 5091947
    Abstract: A voice recognition apparatus includes a coefficient memory for storing at least one coefficient for correcting a degree of similarity which is obtained by either one of the speaker-independent recognition and the speaker-dependent recognition. The apparatus also includes a voice identification circuit for comparing the degrees of similarity of the candidates obtained by either one of the speaker-independent recognition and the speaker-dependent recognition with corrected degrees of similarity of the candidates related to the other recognition type which are obtained by performing a predetermined operation to the degree of similarity of each candidate which is supplied from the other recognition type. Then the voice identification decides one candidate having the highest degree of similarity to be an identification result.
    Type: Grant
    Filed: August 13, 1990
    Date of Patent: February 25, 1992
    Assignee: Ricoh Company, Ltd.
    Inventors: Takashi Ariyoshi, Toshiki Kawamoto, Seigou Yasuda, Syoji Kuriki, Tomofumi Nakatani
  • Patent number: 4945557
    Abstract: An automatic dialing apparatus for use in a telepone or facsimile machine sends out a dial signal to an external network automatically. A detachable telephone number memory, which stores a telephone number together with an area code, is detachably mounted on a telephone unit which includes a memory storing an area code of the district in which the telephone unit is located. The area code of the telepone number data supplied from the telephone number memory is deleted if that area code agrees with the area code stored in the memory of the telephone unit. An automatic dialing apparatus is preferably constructed to carry out dialing automatically responsive to a voice. In the preferred embodiment of such a voice activated dialing apparatus, a telephone number is input through a keyboard and a corresponding identifier, typically the name of a subscriber, is voiced and its voice signal is stored in association with the telephone number.
    Type: Grant
    Filed: April 5, 1989
    Date of Patent: July 31, 1990
    Assignee: Ricoh Company, Ltd.
    Inventors: Kunihiro Kaneuchi, Toshiki Kawamoto, Tomofumi Nakatani
  • Patent number: 4928302
    Abstract: A voice actuated dialing apparatus has a feature extraction part for extracting a feature of an input data, a storage for storing registered standard patterns and corresponding telephone numbers of destination subscribers, a pattern matching part for comparing a standard pattern of the feature extracted by the feature extracting part with the registered standard patterns so as to recognize a predetermined one of the registered standard patterns which matches the standard pattern of the extracted feature, a speech synthesis part for outputting a speech corresponding to the predetermined standard pattern read out from the storage for confirmation of a result of the recognition, and a dialing circuit for dialing to a predetermined one of the registered telephone numbers corresponding to the predetermined standard pattern in a voice-dialing mode.
    Type: Grant
    Filed: November 1, 1988
    Date of Patent: May 22, 1990
    Assignee: Ricoh Company, Ltd.
    Inventors: Kunihiro Kaneuchi, Seigou Yasuda, Takashi Ariyoshi, Tomofumi Nakatani, Hiroshi Aizawa
  • Patent number: 4833717
    Abstract: A voice spectrum analyzing method and system subjects a voice signal to frequency analysis by passing the voice signal through a filter bank containing a plurality of band pass filters each having a different band pass filter range to produce a voice spectral pattern over a predetermined frequency range. The voice spectral pattern is sampled at a predetermined sampling time interval successively, and each of the sampled voice spectral patterns is stored for a predetermined time period. While the voice spectral pattern is retained, it is scanned once in a predetermined time sequence, thereby forming an approximate periodic signal from a series of the scanned voice spectral voice patterns. And the periodic signal thus formed is then digitized and filtered through a digital high pass filter, thereby obtaining a high frequency component from the periodic signal which indicates a feature parameter of the voice signal.
    Type: Grant
    Filed: November 20, 1986
    Date of Patent: May 23, 1989
    Assignee: Ricoh Company, Ltd.
    Inventors: Shogo Nakamura, Tomofumi Nakatani
  • Patent number: 4634966
    Abstract: A frequency spectral distribution of sound signal has a plurality of discrete data at respective channels where sampling takes place. Such a spectral distribution, defining a parallel signal, is converted into a time series signal which is used to produce a peak-detected signal and a zero-cross signal. Then, based on the timing of the zero-cross signal, the peak-detected signal is compared with the original parallel signal to process the original parallel signal to be binary-valued. The present invention provides a simple hardware structure having the above-described function.
    Type: Grant
    Filed: March 19, 1985
    Date of Patent: January 6, 1987
    Assignee: Ricoh Company, Ltd.
    Inventors: Tomofumi Nakatani, Shogo Nakamura