Eastman-kodak Company

Xerox Corporation

Wenjin Zhou

Yongchun Lee

Eric Michael Gross

Mark A Scheuer

Bruce A Link

George O Simmons

John J Alescio

James R Pamper

A scanner for digitizing a document includes a digitizer for digitizing the document into a first color space; a circuit for converting the digitized data into a second color space having a luminance channel and two chrominance channels; a multiplexer having text, approximate actual color of a uniform area and a predetermined color as input for selecting either the text, approximate actual color or the predetermined color as outputs; and multiplexer control input which determines which of the outputs will be selected as actual output based on a uniform area of the document.

High-speed scanner having image processing for improving the color reproduction and visual appearance thereof

An automatic method for processing a color form includes: a) scanning the color form in color space, forming a digital color image, and converting the digital color image into a two-dimensional binary image in chrominance space; and b) conducting a color form dropout process. Also, an automatic color dropout system includes: 1) a color detection system, including means for: (1a) scanning a color document and providing a digital image; (1b) converting the color digital image into luminance-chrominance space; (1c) detecting a background gray level, and assigning it to a Background Value; (1d) measuring color distribution; (1e) detecting the colors present; (1f) generating a color dropout table for each color; and 2) a color dropout system, including means for: (2a) scanning a color form document and providing a digital image; (2b) converting the digital image into luminance-chrominance space; (2c/d) storing and accessing the color dropout table; (2e) applying a color dropout map to the digital image; and (2f) replacing a pixel value with the Background Value.

System and method for image processing by automatic color dropout

Photoreceptor charge control for obviating the adverse effects of photoreceptor variation inherent in the photoreceptor as the result of the manufacturing process. The voltage values around the periphery of the photoreceptor commonly referred to as the V,belt signature are measured. The readings for each of the ESVs are averaged (to find the mean) and the deviations from the mean are smoothed using a 41-term weighting function that properly removes the high frequency reading spikes while retaining the low frequency belt signature. Center weighted averaging of 41 points (n, . . . n&plusmn;20) where n is a measured point on the photoreceptor that is averaged with the previous twenty readings together with the next twenty readings is initiated a few mm past the photoreceptor seam and ends a few mm before the seam&mdash;no phase shift. The readings are taken approximately every 3 mm around the periphery of the photoreceptor.

Photoreceptor charge control

Growing community of inventors

Rochester, NY, United States of America

Wenjin Zhou