Patents by Inventor Doo-Eui Hong

Doo-Eui Hong 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).

  • Apparatus for quantizing a digital image by using an error diffusion coefficient and threshold modulation in zigzag quantization
    Patent number: 6614556
    Abstract: A threshold modulation method, includes the steps of: a) determining whether an input pixel value is greater than a threshold of a current input pixel from the original digital image; b) determining whether an output image value is a predetermined high level or low level based on the threshold; c) if the input pixel value is greater than the threshold and the output image value is the predetermined high level, modulating the threshold of the adjacent pixel; d) if the input pixel value is greater than the threshold and the output image value is the predetermined low level, modulating the threshold of the adjacent pixel; e) if the input pixel value is not greater than the threshold and the output image value is the predetermined low level, modulating the threshold of the adjacent pixel; and f) if the input pixel value is not greater than the threshold and the output image value is the predetermined high level, modulating the threshold of the adjacent pixel.
    Type: Grant
    Filed: November 22, 1999
    Date of Patent: September 2, 2003
    Assignee: Sindoricoh Co., Ltd.
    Inventors: Doo-Eui Hong, Choon-Woo Kim, Gyung-Nam Boo