Xerox Corporation

Ronald E Jodoin

Robert P Loce

Reiner Eschbach

Ying-wei Lin

Michael S Cianciosi

R Victor Klassen

Martin Edward Banton

Peter A Crean

James D Rees

Daniel W Costanza

James J Appel

William L Lama

Thomas J Hammond

Wei Zhu

Henry P Jankowski

Abd-El-Fattah A Ibrahim

The present invention is a method and apparatus for automatic image segmentation using template matching filters. The invention generally segments differing binary textures or structures within an input image by passing one or more structures while removing other structures. More particularly, the method and apparatus segment a stored binary image using a template matching filter that is designed to pass therethrough, for example, text regions while removing halftone regions.

Method and apparatus for automatic image segmentation using template matching filters

Arrays of light emitting diodes, and LED printbars and electrophotographic marking machines that use arrays of light emitting diode, that have active area geometries that produce compact irradiance profiles. Compact irradiance profiles are achieved by placing the diode electrodes along the outer periphery of the light emitting active areas. When used with gradient index lenses, such light emitting diodes produce light spots having more compact irradiance profiles. When such light emitting diodes and gradient index lenses are incorporated into LED printbars, and when those printbars are used in expose stations of electrophotographic marking machines, improved composite images can result.

High resolution printbar pixel geometries

The present invention is a method for antialiased rendering (AAR) of an image. First, tagging methods for identifying antialiased pixels were described, the methods being employed separately or in concert with one another. After identifying AAR pixels, a fill order is determined and applied using a fill order algorithm that preferably employs a pixel window that is a subset of the larger window employed for pixel identification.

Method to enable the recognition and rendering of antialiased images

Method and apparatus for automatic image segmentation using template

The present invention is a method and apparatus for compensating for position error inherent in a raster output scanning printing system by adjusting the intensity of image exposure to effect a correction in the output image. The invention is particularly well suited to compensate for position errors arising from a plurality of sources by first summing the errors and then applying a single compensating adjustment to the intensity of individual scan rasters based upon the position error thereof.

Method and apparatus for compensating for raster position errors in

A method and apparatus for converting the resolution of an input image to a higher resolution that is a noninteger multiple of the input resolution. The method and apparatus employ either an interlocked or noninterlocked clustering arrangement of output pixels in order to assign to each output pixel a reference value determined from the signal levels of the input image. In addition, the method and apparatus include a template-based enhancement filter to further refine modify or alter the assigned signal level prior to its output as a higher resolution image.

Area mapping employing reference clusters for high quality noninteger

The present invention is a method and apparatus for mapping digital image data using paired erosion-based filters. One filter of the pair creates a superset of the output image data and the other a subset of the output image data, and combinatorial logic is then applied to the superset and subset data to obtain the mapped image data. In one embodiment a plurality of erosion-based filters are used where one filter of the pair is extensive and the other filter is antiextensive, each pair generating a sample phase of a high resolution output image.

Method and apparatus employing erosion-based filter pairs for image

The present invention is a an apparatus for enhancing the output along edges of charged area developed regions in a tri-level imaging system employing a pulse width and position modulated signal ROS for exposure. The invention enables the identification and selective alteration of video data used to drive the ROS so as to extend the developed regions by a selected amount and eliminate digitization artifacts present in the image to be printed. The extension of the charged area developed regions is accomplished by reducing or trimming the width of the exposure pulses in adjacent areas to enable development within a portion of those regions.

Method and apparatus for enhancing charged area developed regions in a

The present invention is a method and apparatus for the enhancement of 1 bit per pixel image signals to produce a multiple-bit per pixel form. A binary input image is passed through a plurality of filters to generate level slices. The filters are stack filters implemented as look-up table or template-based filters, morphological filters, or any similar binary-to-binary filters that could be used to generate level slices. Each of the N-1 filters is used to produce the slices, where N is the number of possible gray-scale levels desired in the output image. Once the slices are generated, the resulting binary image data therein is recombined, by adding or stacking, to produce the desired multiple-bit per pixel output.

Stack filters for 1-to-N bit image processing in electronic printers

The present invention is a an apparatus for enhancing the output along edges of discharged area developed regions in a tri-level imaging system employing a pulse width and position modulated signal ROS for exposure. The invention enables the identification and selective alteration of video data used to drive the ROS so as to extend the developed regions by a selected amount and eliminate digitization artifacts present in the image to be printed. The extension of the discharged area developed regions is accomplished by extending the width of, or adding separate, exposure pulses in adjacent areas to enable development within a portion of those regions.

Method and apparatus for enhancing discharged area developed regions in

A multiple diode laser array used in a ROS scanning system is modified to reduce the effects of undesirable spatial exposure variation at the surface of certain type of layered, semi-transparent photoreceptors. The spatial absorption variation is later manifested as a 'plywooding' pattern formed on output prints derived from the exposed photoreceptor. The laser array is modified to form a merged scanning beam at the photoreceptor surface of two or more diode outputs, each output operating at a different wavelength than the other. In one embodiment, a plurality of diodes, each at a different wavelength, are sequentially addressed, and an image of each diode is scanned across the photoreceptor which results in an exposure distribution that would be similar to that formed by an incoherent beam.

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Pittsford, NY, United States of America

Ronald E Jodoin