Patents by Inventor Robert H. Risch

Robert H. Risch 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).

  • Constrained digital halftoning
    Patent number: 6603573
    Abstract: A method and apparatus for halftoning digital images renders color data subject to constraints on the number of colorants which can be deposited on a single pixel and constraints on consecutive pixels rendered with the same color. The color data to be rendered is mapped into a second data set in an achievable color gamut space. Then, using a digital halftoning method in the achievable color gamut space, the second data set is rendered, so that the constraints are satisfied.
    Type: Grant
    Filed: October 30, 1998
    Date of Patent: August 5, 2003
    Assignee: International Business Machines Corporation
    Inventors: Roy L. Adler, Marco Martens, Joan L. Mitchell, Nenad Rijavec, Robert H. Risch, Charles P. Tresser, Chai W. Wu