Patents by Inventor Manabu Joh

Manabu Joh 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).

  • Color image processing apparatus which performs different image processings depending on region of color image
    Patent number: 6731400
    Abstract: A data processing part in a printer controller performs multivalued dither processing whereby image data is processed for images of characters and thin lines with a high definition, and for pictures with a high color gradation, and the image quality deterioration at the boundary region between an edge region and a non-edge region can be avoided. The data processing part performs discrimination of an edge region, a non-edge region, and a boundary region between the edge and non-edge regions. Furthermore, the data processing part performs multivalued dither processing by using a prepared dot distribution type dither matrix for the edge region, a prepared dot concentration type dither matrix for the non-edge region and a prepared dot distribution and concentration mixing type dither matrix for the boundary region.
    Type: Grant
    Filed: October 29, 1997
    Date of Patent: May 4, 2004
    Assignee: Hitachi, Ltd.
    Inventors: Toshiaki Nakamura, Manabu Joh, Tatsuki Inuzuka