Patents by Inventor Hisashi Ibaraki

Hisashi Ibaraki 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).

  • Coding method and apparatus
    Patent number: 4788598
    Abstract: A coding method includes the steps of dividing an image into a plurality of blocks each consisting of a plurality of picture elements, dividing gray scale information of each intrablock picture element into three components, i.e, (1) a reference level representing a position of a signal level of an intrablock picture element in a whole dynamic range of gray scale representation, (2) a level difference representing a distribution range of the signal levels of the intrablock picture elements, and (3) a level designating signal representing a level of each intrablock picture element within the distribution range, and independently coding the three components.
    Type: Grant
    Filed: October 28, 1986
    Date of Patent: November 29, 1988
    Assignee: Nippon Telegraph and Telephone Corp.
    Inventors: Hiroshi Ochi, Makoto Kobayashi, Hisashi Ibaraki, Tetsuji Yamamoto
  • Halftone picture processing apparatus
    Patent number: 4722008
    Abstract: A halftone picture processing apparatus has devices for dividing and storing an image signal in the form of blocks each of which consists of a plurality of pixels, for setting at least one path for accessing the pixels in each block, calculating the number of changes in image signals which satisfies predetermined conditions, the changes occurring between succeeding pixels in each block along the path, and detecting a halftone region in accordance with the number of changes in image signals.
    Type: Grant
    Filed: January 8, 1986
    Date of Patent: January 26, 1988
    Assignee: Nippon Telegraph & Telephone Corporation
    Inventors: Hisashi Ibaraki, Makoto Kobayashi, Hiroshi Ochi