Patents by Inventor Masao Kohchi

Masao Kohchi 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).

  • Method and apparatus for acquiring luminance information and for evaluating the quality of a display device image
    Patent number: 6885369
    Abstract: A method for evaluating the quality of an image, for extracting a luminance gradient displayed on a display device and for evaluating local luminance unevenness caused therein. The method includes the steps of: subdividing the image to be used as an evaluation object into a plurality of pixels; acquiring a first luminance information by calculating the difference between the sum of luminance values of predetermined pixels and the luminance value of a predetermined pixel, the predetermined pixels forming a first pixel group surrounding the predetermined pixel; acquiring a second luminance information by calculating the difference between the sum of luminance values of predetermined pixels and the luminance value of the predetermined pixel, the predetermined pixels constituting a second pixel group; acquiring a third luminance information by adding the first luminance information and the second luminance information; and evaluating the luminance of a screen photographed based on the third luminance information.
    Type: Grant
    Filed: February 13, 2002
    Date of Patent: April 26, 2005
    Assignee: International Business Machines Corporation
    Inventors: Kohsei Tanahashi, Masao Kohchi
  • Method and apparatus for acquiring luminance information and for evaluating the quality of a display device image
    Publication number: 20020118878
    Abstract: A method for evaluating the quality of an image, for extracting a luminance gradient displayed on a display device and for evaluating local luminance unevenness caused therein. The method includes the steps of: subdividing the image to be used as an evaluation object into a plurality of pixels; acquiring a first luminance information by calculating the difference between the sum of luminance values of predetermined pixels and the luminance value of a predetermined pixel, the predetermined pixels forming a first pixel group surrounding the predetermined pixel; acquiring a second luminance information by calculating the difference between the sum of luminance values of predetermined pixels and the luminance value of the predetermined pixel, the predetermined pixels constituting a second pixel group; acquiring a third luminance information by adding the first luminance information and the second luminance information; and evaluating the luminance of a screen photographed based on the third luminance information.
    Type: Application
    Filed: February 13, 2002
    Publication date: August 29, 2002
    Applicant: International Business Machines Corporation
    Inventors: Kohsei Tanahashi, Masao Kohchi