Patents by Inventor Robert V. Klassen

Robert V. Klassen 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 vector error diffusion with output color control
    Patent number: 5621546
    Abstract: A method and apparatus perform vector error diffusion and result in reduced graininess of a color halftone image representing a continuous tone image. The method controls the output colors while reducing the visibility of the error diffusion pattern inherent in forming a bilevel image. Specifically, the method involves influencing the dot pattern correlation using vector error diffusion and takes into account the effects caused by the interactions of dot patters for all of the different color components.
    Type: Grant
    Filed: November 2, 1993
    Date of Patent: April 15, 1997
    Assignee: Xerox Corporation
    Inventors: Robert V. Klassen, Reiner Eschbach, Krishna A. Bharat
  • Method and apparatus for generating and displaying freeform strokes of varying or constant width using adaptive forward differencing
    Patent number: 5341467
    Abstract: Method and apparatus for generating and displaying a freeform stroke of varying or constant width by generating points along a centerline curve and right and left offset curves of the freeform stroke using an adaptive forward differencing technique.
    Type: Grant
    Filed: December 30, 1991
    Date of Patent: August 23, 1994
    Assignee: Xerox Corporation
    Inventor: Robert V. Klassen
  • Method and apparatus for generating and displaying freeform strokes
    Patent number: 5325477
    Abstract: A method and apparatus for generating and displaying points along a centerline curve and right and left offset curves of a freeform stroke, wherein the distances from the centerline curve to the right and left offset curves vary in the same parameter as the horizontal and vertical coordinates of the centerline curve. Preferably, the centerline curve is a spline curve and the points along the centerline curve are generated using a subdivision technique in accordance with predetermined termination criteria.
    Type: Grant
    Filed: December 2, 1991
    Date of Patent: June 28, 1994
    Assignee: Xerox Corporation
    Inventor: Robert V. Klassen