Patents by Inventor Stuart L. Claassen

Stuart L. Claassen 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: 7366746
    Abstract: Finite response filters (FIRs) are divided into partial filters that filter a same portion of image data to generate partial filtered results. The partial filtered results may be saved and later retrieved to generate complete filter outputs.
    Type: Grant
    Filed: February 12, 2004
    Date of Patent: April 29, 2008
    Assignee: Xerox Corporation
    Inventors: Stuart L. Claassen, Jon Q. J. Pocock
  • Patent number: 6567094
    Abstract: A distributed digital imaging processing system having a number of processing units and circular FIFO buffers connected together using data transforming streams. Processing units read data from buffers using a transforming read streams. These read streams reorder the buffer data to form patches representing neighborhood pixels and may provide the same data multiple times. After processing a patch, a processing unit writes the resultant patch into a buffer using a transforming write stream which reorders the data into the storage format of the buffer. Several buffers can feed a single processor and one processor can feed several buffers. All the details of each data stream (buffer, current buffer location, patch size, access pattern) are stored in a table entry, along with a pointer to the data stream that it must follow in the buffer to avoid the hazards of reading and writing data out of order.
    Type: Grant
    Filed: September 27, 1999
    Date of Patent: May 20, 2003
    Assignee: Xerox Corporation
    Inventors: Donald J. Curry, David B. Kasle, James L. Ball, Todd W. Thayer, Stuart L. Claassen
  • Patent number: 6148376
    Abstract: An apparatus and method for an improved stack comprises an advantageous indexing scheme and stack arrangement allowing more efficient performance of stack operations. The most-recently-used stack item appears at the top of the stack and the least-recently-used item is at the bottom of the stack. Values in between the top and bottom items are ordered from top to bottom with succeedingly less recently used items. An indexing scheme is used to indirectly reference locations of the stack items in the stack. A set of registers is used to reference the locations of the stack items in an embedded memory array. The registers function as pointers to the memory array locations. To promote an item to the top of the stack, the item is identified as the most-recently-used and the contents of the other registers are changed to specify the new locations, e.g. these pointers are shifted down one.
    Type: Grant
    Filed: September 30, 1996
    Date of Patent: November 14, 2000
    Assignee: Apple Computer, Inc.
    Inventor: Stuart L. Claassen
  • Patent number: 6028962
    Abstract: A system and method for efficient image encoding begins by loading a series of image blocks. A current block is compared with an immediately preceding image block for coincidence, and coded as matching or nonmatching based on the comparison results. The system further compares the nonmatching image blocks with a stack containing a list of the most recently encountered image blocks. Image blocks matching an entry in the list are coded by reference to the appropriate entry in the list. In the event a match is still unavailing, the system determines if the image blocks may be categorized as a bilevel text block, a bilevel image block, a block containing only one gray pixel, or a block containing multiple gray pixels. Each nonmatching block is classified according this classification criteria.
    Type: Grant
    Filed: May 10, 1996
    Date of Patent: February 22, 2000
    Assignee: Apple Computer, Inc.
    Inventors: Stuart L. Claassen, Kok S. Chen, Riaz A. Moledina
  • Patent number: 5903675
    Abstract: A system and method for efficient image compression begins by segmenting an input image into a current and previous window using a loading module. An encoding module compares the current and the previous window. If the current window does not match the previous window, the encoding module alters the dimensions of the current and previous windows and repeats the comparison. If a match is found, the encoding module instructs the loading module to continue to segment the image using the altered window dimensions. In this manner, the system's segmenting is in step with the natural cycle of repetition in the input image.
    Type: Grant
    Filed: December 20, 1996
    Date of Patent: May 11, 1999
    Assignee: Apple Computer, Inc.
    Inventors: Riaz A. Moledina, Stuart L. Claassen, Kok S. Chen
  • Patent number: 5596352
    Abstract: A printer and a method for printing is described in which bleed between secondary color regions having different colors is minimized by the formation of a border strip which has a color which is common to both secondary color regions. In a printer assembly which includes a print head for depositing ink onto a media, an improved image may be formed by processing the data before the image is printed such that a border strip is formed between adjoining regions of different secondary colors. The border strip is printed in a color which is common to both of the secondary color regions. Thus, because the color which is common to both secondary color regions is printed in the border region, the contrast between the three areas of different colors is minimized. In addition, the reduced volume of ink within the border strip further minimized ink bleed. Thus, a border strip which is significantly less visible to the naked eye, is formed which minimizes bleed between the two secondary color regions.
    Type: Grant
    Filed: September 23, 1993
    Date of Patent: January 21, 1997
    Assignee: Apple Computer, Inc.
    Inventors: Anitta L. Bliss, Stuart L. Claassen
  • Patent number: 5506609
    Abstract: A method is described for optimizing printing a first print dot, a second print dot, a third print dot, and a fourth print dot adjacent to each other on a sheet of paper. The method first determines whether the first, second, third, and fourth print dots to be printed are in black color. If any one of the first, second, third, and fourth print dots is in the black color, then the respective one of first, second, third, and fourth print dots needs to be double printed with the black color. If the first and second print dots are in the black color and the third and fourth print dots are color print dots, then the first and second print dots are printed with the black color and the third color print dot is printed during a first print pass by the printer.
    Type: Grant
    Filed: June 30, 1993
    Date of Patent: April 9, 1996
    Assignee: Apple Computer, Inc.
    Inventors: Stuart L. Claassen, Joseph Ku, Anitta L. Bliss
  • Patent number: 4748453
    Abstract: A method of depositing spots of liquid ink upon selected pixel centers on a substrate having poor ink absorptive properties so as to prevent the flow of liquid ink from one spot to an overlapping adjacent one. The line of information is printed in at least two passes so as to deposit spots of liquid ink on selected pixel centers in a checkerboard pattern wherein only diagonally adjacent pixel areas are deposited in the same pass. On the second pass the complementary checkerboard pattern is deposited. Ink is not deposited on horizontally or vertically adjacent pixel areas during the single pass since the spots on these adjacent areas have overlapping portions.
    Type: Grant
    Filed: July 21, 1987
    Date of Patent: May 31, 1988
    Assignee: Xerox Corporation
    Inventors: Larry W. Lin, Stuart L. Claassen, Chein-Hwa Tsao
  • Patent number: RE43301
    Abstract: An apparatus and method for an improved stack comprises an advantageous indexing scheme and stack arrangement allowing more efficient performance of stack operations. The most-recently-used stack item appears at the top of the stack and the least-recently-used item is at the bottom of the stack. Values in between the top and bottom items are ordered from top to bottom with succeedingly less recently used items. An indexing scheme is used to indirectly reference locations of the stack items in the stack. A set of registers is used to reference the locations of the stack items in an embedded memory array. The registers function as pointers to the memory array locations. To promote an item to the top of the stack, the item is identified as the most-recently-used and the contents of the other registers are changed to specify the new locations, e.g. these pointers are shifted down one.
    Type: Grant
    Filed: October 10, 2002
    Date of Patent: April 3, 2012
    Assignee: Apple Inc.
    Inventor: Stuart L. Claassen