Patents Represented by Attorney, Agent or Law Firm Michelle W. Waites
  • Patent number: 6563955
    Abstract: A method and apparatus for compressing digital image data to improve the efficiency of serial data transmission is disclosed. More specifically, the present invention accomplishes image transmission by providing multiple image processing modules, and then selecting the module that will process the entire in the most efficient manner, based upon the content of the data contained in the image. Image content is analyzed using hierarchical vector quantization.
    Type: Grant
    Filed: November 13, 1998
    Date of Patent: May 13, 2003
    Assignee: Xerox Corporation
    Inventor: Ricardo L. de Queiroz
  • Patent number: 6400844
    Abstract: An improved technique for compressing a color or gray scale pixel map representing a document using an MRC format includes a method of segmenting an original pixel map into two planes, and then compressing the data or each plane in an efficient manner. The image is segmented by separating the image into two portions at the edges. One plane contains image data for the dark sides of the edges, while image data for the bright sides of the edges and the smooth portions of the image are placed on the other plane. This results in improved image compression ratios and enhanced image quality.
    Type: Grant
    Filed: December 2, 1998
    Date of Patent: June 4, 2002
    Assignee: Xerox Corporation
    Inventors: Zhigang Fan, Ming Xu
  • Patent number: 6334001
    Abstract: A method and apparatus for compressing a mixed raster content image that represents a color or gray scale a document is disclosed. The pixel map is decomposed into a three-plane representation—a reduced-resolution “upper” plane, a reduced-resolution “lower” plane, and a high-resolution binary selector plane. An iterative smoothing technique is then used to pre-process the upper and lower planes using the information contained in the selector plane, thereby reducing the amount of data that will be subjected to further processing.
    Type: Grant
    Filed: December 7, 2000
    Date of Patent: December 25, 2001
    Assignee: Xerox Corporation
    Inventors: Ricardo L. de Queiroz, Reiner Eschbach, William A. Fuss, Robert R. Buckley
  • Patent number: 6275620
    Abstract: An improved technique for processing a color or gray scale pixel map representing a document is disclosed. The pixel map is decomposed into a three-plane representation, a reduced-resolution “upper” plane, a reduced-resolution “lower” plane, and a high-resolution binary selector plane. The “upper” and “lower” planes contain the color or gray scale for the page as well as the continuous tone pictures that are contained on the page. The selector plane stores information for selecting from either the foreground plane or background plane during decompression. Information contained in the selector plane is first used to pre-process the upper and lower planes to reduce the amount of data on each of the other two planes that will be subjected to further processing. Each of the pre-processed planes is compressed using a compression technique optimal for the type of data that resides upon it.
    Type: Grant
    Filed: December 7, 2000
    Date of Patent: August 14, 2001
    Assignee: Xerox Corporation
    Inventors: Ricardo L. de Queiroz, Reiner Eschbach, William A. Fuss, Robert R. Buckley
  • Patent number: 6268939
    Abstract: The present invention is directed to a method and apparatus for improving the efficiency of color correcting subsampled luminance and chrominance based data. More specifically, the present invention is directed to a method of applying a full conversion between color spaces for one pixel in a selected pixel block. Chrominance values are assigned to the remaining pixels based upon their luminance values relative to the luminance value of the converted pixel. The invention may be used to convert between various types of color spaces, and may be used in the processing of both device dependent and device independent data.
    Type: Grant
    Filed: January 8, 1998
    Date of Patent: July 31, 2001
    Assignee: Xerox Corporation
    Inventors: R. Victor Klassen, Thyagarajan Balasubramanian
  • Patent number: 6256421
    Abstract: A method and apparatus for efficiently transmitting digital image data is disclosed. More specifically, the present invention accomplishes fast data transmission by analyzing the content of input data, and then retrieving data that closely matches that which would be produced if the data were subjected to some form of data compression from storage. The retrieved data is transmitted to the retrieving device, thereby eliminating the need for very time consuming data compression processes.
    Type: Grant
    Filed: December 7, 1998
    Date of Patent: July 3, 2001
    Assignee: Xerox Corporation
    Inventor: Ricardo L. de Queiroz
  • Patent number: 6239886
    Abstract: The present invention is directed to a method and apparatus for improving the efficiency of color correcting subsampled luminance and chrominance based data. More specifically, the present invention is directed to a method of applying a full conversion between color spaces for one pixel in a selected pixel block. Chrominance values are assigned to the remaining pixels based upon their luminance values relative to the luminance value of the converted pixel. The invention may be used to convert between various types of color spaces, and may be used in the processing of both device dependent and device independent data.
    Type: Grant
    Filed: January 8, 1998
    Date of Patent: May 29, 2001
    Assignee: Xerox Corporation
    Inventors: R. Victor Klassen, Thyagarajan Balasubramanian
  • Patent number: 5826139
    Abstract: A method and apparatus for reproducing high quality images using an electrophotographic printing machine is disclosed.More specifically, the present invention is used to change the location, shape and size of a process control patch. Process control patches may be used to improve the quality of an image prior to printing. The intensity of light reflected from the control patch is measured, and the measurements are used to change parameters such as magnitude of electrostatic charge, and toner concentration, before the latent image developed. Adjusting these parameters at this time will allow the printing apparatus to reproduce images having superior quality than previously available.
    Type: Grant
    Filed: September 30, 1996
    Date of Patent: October 20, 1998
    Assignee: Xerox Corporation
    Inventors: Aron Nacman, Roger W. Budnik, Guru B. Raj
  • Patent number: 5794176
    Abstract: A method and apparatus for positioning paper in a feed path by providing continuous feedback of copy sheet registration parameters is disclosed. More specifically, the present invention is directed to a system which compares measured sheet registration information with an ideal value stored in a microprocessor. These measured registration parameters are averaged and pertinent information is fed back to the control system of the copy sheet registration device. The information that has been fed back is then used to adjust the orientation of subsequent copy sheets, thereby allowing for ideal placement of the copy sheet onto the photoreceptor for successful transfer of a developed image.
    Type: Grant
    Filed: September 24, 1996
    Date of Patent: August 11, 1998
    Assignee: Xerox Corporation
    Inventor: William D. Milillo
  • Patent number: 5781451
    Abstract: A method and apparatus for using one moving system to transmit output data in a pattern that is dependent upon the motion of another moving system is disclosed. More specifically, the present invention enables a line writing device, such as a raster output scanner or a thermal inkjet array, to transmit imaging data to a target, typically an imaging member or a recording medium, in a pattern that is dependent upon the motion of the target. Thus, if motion of the target is altered due to wear and tear, malfunctioning of the printing machine, or for any other reason, the line writing device will adjust its data transmission rate to cause the imaging data to strike its target in the appropriate location.
    Type: Grant
    Filed: January 21, 1997
    Date of Patent: July 14, 1998
    Assignee: Xerox Corporation
    Inventors: Robert M. Lofthus, Stuart A. Schweid
  • Patent number: 5777319
    Abstract: A method of accomplishing rotational alignment of laser arrays relative to an external optical axis is described. The method uses the laser polarization, which is oriented relative to the axis of the array, as the means of determining the laser array rotational orientation. The method can be rapidly executed in a manual or automatic procedure, has accuracy of better than 0.1 degree, and can be used to orient a laser array at any chosen angle with reflect to an external optical axis.
    Type: Grant
    Filed: March 26, 1997
    Date of Patent: July 7, 1998
    Assignee: Xerox Corporation
    Inventor: John R. Andrews
  • Patent number: 5709505
    Abstract: Disclosed is a process for removing contaminants from a contaminated area of the subsurface which comprises providing a borehole in the contaminated area; placing in the borehole a perforated riser pipe inside of which is situated a vacuum extraction pipe with an opening situated within the perforated riser pipe, wherein a packing is situated in a portion of the annular space between the vacuum extraction pipe and the perforated riser pipe; applying a vacuum to the vacuum extraction pipe to draw gases and liquid from the subsurface into the perforated riser pipe below the packing and from the riser pipe into the vacuum extraction pipe and transport both the gases and the liquid to the surface as a common stream; forming from the common stream a stream which is primarily liquid and a stream which is primarily gaseous; and removing contaminants from at least one of the liquid stream and the gaseous stream. Also disclosed is an apparatus for carrying out the disclosed process.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: January 20, 1998
    Assignee: Xerox Corporation
    Inventors: Richard A. Williams, Ronald E. Hess, Michael T. Salotti, John F. Thomasser, Scott M. Huber, Eliott N. Duffney, Alfonso R. Mancini
  • Patent number: H1805
    Abstract: This invention discloses a method and apparatus for properly placing copy sheets from a high speed copy machine into an exit tray. The invention utilizes a variable speed motor to control the rollers which reside at the end of the paper path. One or more paper guides mounted to the drive rollers, enable the motor to operate over a wide range of speeds, yet still work efficiently. The motor accelerates to its highest speed as the copy sheet enters the nip between the drive and idler rollers, and is decelerated to its slowest speed as the trailing edge of the copy sheet exits the nip. The trailing edge of the copy sheet then moves off of the roller and onto the paper guide. The speed of the motor can then be increased without having to wait for the copy sheet to move into the output area. This substantially reduces the period of time required to reproduce copies.
    Type: Grant
    Filed: June 17, 1996
    Date of Patent: October 5, 1999
    Assignee: Xerox Corporation
    Inventors: Jason P. Rider, Russell C. Rackett, Joseph S. Vetromile, Geoffrey C. Williams