Xerox Corporation

Raymond J Clark

Stuart Alan Schweid

Jeng-nan Shiau

Leon C Williams

Roger Lee Triplett

Timothy Patrick Foley

Frank Berkelys Tamarez Gomez

Paul S Bonino

Zhigang Fan

David Jon Metcalfe

Martin L Frachioni

Robert P Loce

Reiner Eschbach

David Allen Mantell

Michael E Farrell

Peter A Crean

William A Fuss

Daniel Davies

David E Rumph

Michael Branciforte

Dale T Platteter

Farzin Blurfrushan

Terri A Clingerman

Isaak Rivshin

Michael W Marchetti

A method of printer operation identifies inkjets to operate in each scanline to eject sneeze drops or, in an alternative approach, identifies the cross-process direction scanlines within a page to be printed by the printer where each inkjet ejects sneeze drops. The methods use a binary grayscale code counter that generates a sequence of binary grayscale code numbers and every other output of the sequence is bit reversed to spread the sneeze drops over the pages of the printer output so the sneeze drops are not perceptible to a human observer.

Methods for operating printhead inkjets to attenuate ink drying in the inkjets during printing operations

A method and system compensates for malfunctioning inkjets using contone values for an image prior to the contone values being rendered for printing of the image. The method generates contone values for color space components in a compensation level for each malfunctioning inkjet. The contone values in each compensation level are modified with reference to a profile selected for each malfunctioning inkjet and with reference to the modification of the contone values in the vicinity of each malfunctioning with the compensative level. The modified contone values of each compensation level are merged with the contone values in the vicinity of each malfunctioning inkjet. The contone values are then rendered and used to operate inkjets for forming an ink image on an ink receiving member.

System and method for compensating for malfunctioning inkjets

A printer detects malfunctioning ejectors during printing of three-dimensional objects or two-dimensional printed matter. The printer operates the printhead or printheads in the printer to form convex drops of material on a substrate. A camera is positioned to minimize light reflections from the substrate into the camera. The camera is configured to generate image data of the light reflected from the substrate and specularly from the convex drops on the substrate. A controller analyzes the image data to identify malfunctioning inkjets.

System for detecting malfunctioning ejectors in three-dimensional object printing using specular reflectance

An apparatus detects inoperative ejectors during printing of three-dimensional objects. The apparatus operates the printhead or printheads in the printer to form test pattern on a substrate. A pneumatic sensor directs a pneumatic stream towards substrate and measures the pneumatic impedance. The impedance differences between area where the test pattern is formed and bare areas are analyzed to identify inoperative inkjets.

System for detecting inoperative ejectors in three-dimensional object printing using a pneumatic sensor

An apparatus detects inoperative inkjets during printing. The apparatus includes a light transmitting substrate onto which a test pattern of material is ejected. A light source directs light into the substrate and an optical sensor generates image data of a surface of the substrate. Light propagates through the substrate unless it reaches a position where the material is present on the surface. Thus, the material emits light so a contrast exists between the surface of the substrate and the material emitting light. By comparing the image data to the positions of the light emitting areas on the surface, inoperative inkjets are detected.

System for detecting inoperative inkjets in printheads ejecting clear ink using a light transmitting substrate

An inkjet printer estimates ink usage in the printer with reference to image pixels and a history of inkjet firing for each inkjet. The printer includes an apparatus that generates an ink mass for each image pixel with reference to the image pixel and a predetermined number of previously ejected image pixels and identifies a total ink mass measurement for a printhead with reference to the ink masses generated for the image pixels of an image to be printed by the inkjet printer.

System and method for estimating ink usage in an inkjet printer

Disclosed is a processor-implemented method for processing images. The processor receives image data of a color space defined by input provided to a system by a user, determines at least one color attribute of the pixels in the received image correlating to at least perceptual image characteristics, determines statistics using the attribute(s), and analyzes the statistics to classify the image into a category. Based on at least the category, a billing structure for the image is determined. For example, chroma and/or hue of pixels can be used to create histograms, whose data is used to determine a degree of color and/or content of an image, which is categorized. Color space components of received pixels can also be statistically analyzed. Such determinations consider billing based on human perception of use of color. Billing for color images in this manner satisfies the user and increases use of color output (e.g., printing).

Method and system for billing based on color component histograms

The present application provides a mixed resolution, interleaving-based, cross-channel data flow and data format for a printer image path. The architecture provides pixel data for a colorant of a given writing channel at its nominal (full) resolution, while pixel data for other colorants is provided at lowered resolution. Pixel data for a primary channel at its full resolution is interleaved with data for other secondary channels at lower resolution. Known sub-sampling or compression techniques can be used to lower the resolution of the secondary channels. The data at the different resolutions is generated by the digital front end (DFE), which distributes the data for each writing channel at the time it is needed. Preferably, the low resolution data is sent first to the writer, followed by high resolution data, so that data buffering is minimized.

Data architecture for mixed resolution interleaved cross-channel data flow and format

Systems and methods are described that facilitate identifying objects in a document (e.g., a PDF document) for automatic image enhancement (AIE). A PDF document is 'chunked' or segmented into chunks, and boundaries between chunks are identified as real or imaginary. Chunks sharing imaginary boundaries are combined, while real boundaries are retained, to generate 'de-chunked' objects. These objects are then classified, and an AIE application is executed on objects meeting pre-specified classification criteria. In this manner, objects of r which AIE is not desired are not subjected to the AIE application, thereby saving time and processing resources associated with enhancing the document.

PDF de-chunking and object classification

A system renders print jobs via a marking engine. A raster image processor receives the job from the input module and renders it to one or more raster images. One or more contone image processors receive the one or more raster images to perform cross-channel image processing to render the raster images into a form compatible with the marking engine, wherein the output is partially sub-partitioned by color separation. An image refactoring and distribution network completes the sub-partitioning by separation of the rendered contone raster images by color separation and distributes each color sub-partition to a marker channel module specific to each color sub-partition. A marking engine receives the color sub-partitioned image data, marks the image onto a substrate and outputs a hardcopy of the image.

Distributed data flow for page parallel image processing within printing systems

A method and apparatus are provided for determining a weighted average measured reflectance parameter R for pixels in an image for use in integrated cavity effect correction of the image. For each pixel of interest P in the image, an approximate spatial dependent average A , B of video values in a region of W pixels by H scan lines surrounding the pixel of interest P is computed by convolving video values V of the image in the region with a uniform filter. For each pixel of interest P a result of the convolving step is used as the reflectance parameter R . The apparatus includes a video buffer for storing the pixels of the original scanned image, and first and second stage average buffers for storing the computed approximate spatial dependent averages A , B . First and second stage processing circuits respectively generate the first and second stage average values A , B by convolving the video values of the image in a preselected region with a uniform filter.

Method and apparatus for implementing integrated cavity effect correction in scanners

A method and apparatus are disclosed for distinguishing noisy continuous tone document types from other document types such as halftone or text, in order to maintain reliable image segmentation. In both cases a Range of Video microclassifier is added to the other microclassifiers (Sij, estimated halftone frequency, etc.) to disqualify noisy continuous tone images from being incorrectly classified as other document types such as halftone or text document types.

Method and apparatus for distinguishing between noisy continuous tone document types and other document types to maintain reliable image segmentation

A system and method classify a pixel of image data as one of a plurality of image types. A first image characteristic value for the pixel, a second image characteristic value for the pixel, a third image characteristic value for the pixel, and a fourth image characteristic for the pixel is determined. Some of these determinations may be resolution dependent. The values from these determination are utilized in assigning an image type classification to the pixel. An auto-segmentation circuit enables classifying a pixel as a continuous tone and detecting a gradient in the window of pixels of which the pixel is a member. A filter enhances the image data of the pixel tone when a gradient indicating that image data within the window of pixels is changing at a rate greater than a predetermined threshold is detected or lowpasses the image data of the pixel tone when a gradient indicating that image data within the window of pixels is changing at a rate less than a predetermined threshold is detected.

Method and system for classifying and processing of pixels of image data

A system and method classify a pixel of image data as one of a plurality of image types. A first image characteristic value for the pixel, a second image characteristic value for the pixel, a third image characteristic value for the pixel, and a fourth image characteristic for the pixel is determined. Some of these determinations may be resolution dependent. The values from these determination are utilized in assigning an image type classification to the pixel. Moreover, if at least one of the image characteristic values is greater than a predetermined threshold value the pixel is classified as a halftone peak value. The system includes a plurality of microclassifiers for determining a distinct image characteristic value of the pixel; a plurality of macroreduction circuits connected to the plurality of microclassifiers for performing further higher level operations upon the distinct image characteristic values of the pixel to produce reduced values; and a classification circuit to classify the pixel as an image type based on the reduced values from the macroreduction circuits. The system also includes a circuit to detect flat peaks without detecting multiple peaks and a rectangular blur filtering system.

A system and method electronically image process a pixel belonging to a set of digital image data with respect to a membership of the pixel in a plurality of image classes. This process uses fuzzy classification to determine a membership value for the pixel for each image classes and generates an effect tag for the pixel based on the fuzzy classification determination. The pixel is image processed based on the membership vector of the pixel. The determination of the membership value also includes the determination of the halftone frequency of the pixel. The present process injects random noise into the frequency estimate before classification to avoid having a sharp shift in the pixel classification population as the ripple in the frequency microclassifier crosses the quantization threshold.

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Webster, NY, United States of America

Raymond J Clark