Patents by Inventor Patrick D. Charles

Patrick D. Charles 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).

  • Patent number: 5602941
    Abstract: This disclosure relates to an image processing system which relies upon quantization and dithering techniques to enable an output device, which has a given number of output levels, to accurately reproduce a image which is generated by an input device, which has a greater or equal number of input levels. Generally, neither the number of input nor output levels need to be a power of two. The present invention is implemented in a number of different embodiments. These embodiments generally rely upon an image processor which, depending on the particular implementation, includes memory devices and an adder, a comparator, or a bit shifter. Additional embodiments use an image adjustment system or an image modification system to refine the raw input levels of the input device, in order to create an improved output image. Also, the particular embodiments of the image processors can be used in connection with imaging systems having bi-tonal, monochromatic, or color input and output devices.
    Type: Grant
    Filed: May 21, 1993
    Date of Patent: February 11, 1997
    Assignee: Digital Equipment Corporation
    Inventors: Patrick D. Charles, Robert S. McNamara, Robert A. Ulichney
  • Patent number: 5307292
    Abstract: A fractal-based or "patchwork" method for analyzing topographic data simulates covering the surface of a specimen surface with triangular patches in order to determine the relative surface area which is a function of patch size or scale of observation or interaction. The specimen surface has X and Y horizontal axes and a vertical Z axis. Height data is obtained for each point of a grid network of points on the surface, the points being arranged in parallel rows and the rows being spaced. The specimen surface is defined with triangles having a surface area equal to a preselected patch area value. The total area of the planar triangles is calculated to obtain a total measured area of value. The area of the specimen surface in the X-Y plane that is defined by the triangles is calculated to obtain a total measured area value. The total measured area value is divided by the total projected area value to obtain a relative area value.
    Type: Grant
    Filed: June 24, 1992
    Date of Patent: April 26, 1994
    Assignee: Christopher A. Brown
    Inventors: Christopher A. Brown, William A. Johnsen, Patrick D. Charles