Douglas Neil Curry

US Patent:

6346993, Feb 12, 2002

Filed:

Feb 5, 1999

Appl. No.:

09/244767

Inventors:

Douglas N. Curry - Menlo Park CA

Assignee:

Xerox Corporation - Stamford CT

International Classification:

H04N 146

US Classification:

358 19, 358534, 358536, 358456, 358298, 358454

Abstract:

An image generating system that warps both the image data and halftone screens of a halftone screen system to minimize moirà patterns. Merely warping image data to minimize moirà patterns results in offsets within the image data which should have a corresponding adjustment or warp in halftone screens used in the image generating system to render the color image separation layers. Therefore, the image generating system provides moirà pattern minimization by warping screens of the halftone screen system to correspond to the warping of the image data. The image generating system uses line screens for halftoning the chromatic image separation layers of color images and a hexagonal dot screen for halftoning the luminescent image separation layer. The halftone screen system uses the relatively large average screen displacement angles offered by line screening while providing a dynamic tone range performance similar to that of the performance of dot screening.

US Patent:

6519055, Feb 11, 2003

Filed:

Mar 30, 2000

Appl. No.:

09/539493

Inventors:

Douglas N. Curry - Menlo Park CA
Donald J. Curry - Menlo Park CA

Assignee:

Xerox Corporation - Stamford CT

International Classification:

G06K 1500

US Classification:

358 21, 358 302, 358 327, 358462, 382300, 347253

Abstract:

A hyperacuity printing system for rendering bitmapped image data on a photosensitive recording medium, the bitmapped image data being rendered as an array of pixels across the photosensitive recording medium in a fastscan direction, and an orthogonal slowscan direction. This system includes a data source for supplying grayscale input image data and a scanning device for rendering grayscale output image data onto the recording medium. The scanning device has a device for writing scan spots on the recording medium. Further included in this system is transformation circuitry for transforming the grayscale input image data into grayscale output image data. The transformation circuitry includes a halftoner, a thresholder, and a selection device, where the selection device selects either the thresholder or the halftoner to provide the grayscale output image data. Finally, included is a modulating device coupled between the transformation circuitry and the scanning device for intensity modulating each of the scan spots in accordance with the grayscale output image data.

US Patent:

6608701, Aug 19, 2003

Filed:

Jul 7, 1999

Appl. No.:

09/348378

Inventors:

Robert P. Loce - Webster NY
Michael Branciforte - Rochester NY
Fritz F. Ebner - Rochester NY
Douglas N. Curry - Menlo Park CA
Yeqing Zhang - Penfield NY
Leon C. Williams - Walworth NY

Assignee:

Xerox Corporation - Stamford CT

International Classification:

G06K 936

US Classification:

358 309, 358 314

Abstract:

A compact rendering processor for processing image data including a multi-bit halftone region generates high addressability pixels. The compact rendering processor includes a tagging sub-processor operating on the image data to identify a target pixel and a neighboring pixel to determine a fill-order. The compact rendering processor also includes a rendering sub-processor that converts the target pixel into a high addressability pixel based upon the fill-order. Optionally, a diffusion sub-processor can be included to diffuse an error resulting from the conversion of the target pixel into a high addressability pixel to other pixels within the image data.

US Patent:

6707481, Mar 16, 2004

Filed:

Jan 19, 2000

Appl. No.:

09/487544

Inventors:

Robert T. Krivacic - San Jose CA
Alan G. Bell - Palo Alto CA
Douglas N. Curry - Palo Alto CA

Assignee:

Xerox Corporation - Stamford CT

International Classification:

B41J 247

US Classification:

347239, 347255

Abstract:

A light source modulator and method of modulating a light source use a lower bandwidth input signal during rendering of image data, which is less susceptible to systematic error. The modulation scheme improves the efficiency of use of high speed memory by limiting a number of intensity level transitions to a single transition per output pixel. In conjunction with the limitation of transitions per rendering of each output pixel, data is provided to the modulator that indicates an intensity level to be provided by the modulator and a timing of a transition to that intensity level. In accordance with the exemplary embodiments of the invention, an intensity level may be a minimum intensity level, a maximum intensity level and at least one intermediate intensity level which is intermediate between the minimum and maximum intensity levels.

US Patent:

6771827, Aug 3, 2004

Filed:

Dec 23, 1998

Appl. No.:

09/219850

Inventors:

Douglas N. Curry - Menlo Park CA

Assignee:

Xerox Corporation - Stamford CT

International Classification:

G06K 946

US Classification:

382239, 382232, 382233

Abstract:

A compression and decompression system and process for optimally compressing and decompressing multibit per pixel image regions based on the type of data contained in the image region, e. g. , whether the image region contains continuous tone data, including data to be halftoned, or non-continuous tone data, including antialiased text and lineart data. Segmented bytemap data blocks are processed to provide both low spatial resolution continuous tone data and high spatial resolution non-continuous tone data. However, the high spatial resolution non-continuous tone data is generated by quantizing and packing the high resolution bytes across an edge and discarding the high resolution bytes along the edge, i. e. , the multibit data is discarded only in directions parallel to the edges of marks to be rendered in the image data. Additional information indicating the directions of the edges in the image data are stored to aid in decompression.

US Patent:

6798541, Sep 28, 2004

Filed:

Jun 29, 2001

Appl. No.:

09/681967

Inventors:

Douglas N. Curry - Palo Alto CA

Assignee:

Xerox Corporation - Stamford CT

International Classification:

H04N 140

US Classification:

358 299, 358 19, 358 301, 358 307, 382299

Abstract:

The result of integrating a halftone dot-shape can be clustered. When the edge of the halftone dot-shape extends across a âverticalâ edge of a window, the window is altered until the edge of the halftone dot-shape no longer crosses either vertical edge of the altered window. The image density of the portion of the halftone dot-shape contained within the altered window is determined. The block of image density of the portion of the halftone dot shape contained within the altered window is aligned with the right edge, the left edge, split between the left and right edges, or clustered in the âcenterâ of the altered window. An amount of the determined block that extends into the original sample window is determined. This amount extending into the original window determines the amount of image density to be generated in the final output image based on that sample location of the window.

US Patent:

6853754, Feb 8, 2005

Filed:

Aug 25, 2003

Appl. No.:

10/646766

Inventors:

Douglas N. Curry - Menlo Park CA, US

Assignee:

Xerox Corporation - Stamford CT

International Classification:

G06K009/36

US Classification:

382237, 382239, 382169, 382318

Abstract:

A compression and decompression system and process for optimally compressing and decompressing multibit per pixel image regions based on the type of data contained in the image region, e. g. , whether the image region contains continuous tone data, including data to be halftoned, or non-continuous tone data, including antialiased text and lineart data. Segmented bytemap data blocks are processed to provide both low spatial resolution continuous tone data and high spatial resolution non-continuous tone data. However, the high spatial resolution non-continuous tone data is generated by quantizing and packing the high resolution bytes across an edge and discarding the high resolution bytes along the edge, i. e. , the multibit data is discarded only in directions parallel to the edges of marks to be rendered in the image data. Additional information indicating the directions of the edges in the image data are stored to aid in decompression.

US Patent:

6970259, Nov 29, 2005

Filed:

Nov 28, 2000

Appl. No.:

09/722362

Inventors:

Teresa F. Lunt - Palo Alto CA, US
Matthew K. Franklin - Davis CA, US
David L. Hecht - Palo Alto CA, US
Thomas A. Berson - Palo Alto CA, US
Mark J. Stefik - Portula Valley CA, US
R. Drew Dean - Cupertino CA, US
Alan G. Bell - Palo Alto CA, US
Thomas M. Breuel - Brisbane CA, US
Todd A. Cass - San Francisco CA, US
Douglas N. Curry - Palo Alto CA, US
Daniel H. Greene - Sunnyvale CA, US
Robert T. Krivacic - San Jose CA, US

Assignee:

Xerox Corporation - Stamford CT

International Classification:

G06K001/00

US Classification:

358 114, 358 328, 358 115, 382100, 382135, 713176, 713186

Abstract:

A print management system includes a policy that determines a protection level for a document to be printed. The document is printed using forgery detection and deterrence technologies, such as fragile and robust watermarks, glyphs, and digital signatures, that are appropriate to the level of protection determined by the policy. A plurality of printers are managed by a print management system. Each printer can provide a range of protection technologies. The policy determines the protection technologies for the document to be printed. The print management system routes the print job to a printer that can apply the appropriate protections and sets the appropriate parameters in the printer. Copy evidence that can establish that a document is a forgery and/or tracing information that identifies the custodian of the document and restrictions on copying of the document and use of the information in the document are included in the watermark that is printed on the document. A document can be verified as an original or established as a forgery by inspecting the copy evidence and/or tracing information in the watermark.