Inventors list

Assignees list

Classification tree browser

Top 100 Inventors

Top 100 Assignees


Edul N. Dalal, Webster US

Edul N. Dalal, Webster, NY US

Patent application numberDescriptionPublished
20090268218HYPOCHROMATIC IMAGING - Color management constraints on the use of selected hypocolorant(s) and a black colorant in the rendering of a given pixel reduce ink or toner usage and/or reduce pressure on an ink limit. Additionally, the enforcement of this mutual exclusivity between the black and the selected hypocolorant(s) allows screen frequencies and angles to be shared between halftone screens used for the black colorant and a selected hypocolorant. This reduces the likelihood of objectionable moiré associated with the use of hypocolorant colorants in addition to the conventional CMY(K) colorants. In some embodiments, color management constraints prevent the use of black colorant for pixels beyond a threshold lightness or luminance. This constraint allows the use of the selected hypocolorants in the region of color space beyond the threshold. The threshold can be a function of hue and/or chroma. In some embodiments the threshold is a constant.10-29-2009
20100119158POSITIONAL DISTORTION COMPENSATION - A de-warp map is generated by applying principal component analysis (PCA) to vectors describing aspects of identified features of an object in an image. PCA provides vectors and coefficients describing curvature or image warping at selected points in the image. Estimates of the warping of the image generally are generated by interpolation and/or extrapolation from the vectors and coefficients provided by PCA. In some applications only two features need be identified. For example, the complicated curvature of the facing pages of an open book can be characterized by two vectors describing positions of top and bottom edges of the book. In such applications PCA can reduce to vector subtraction to determine a basis vector, vector addition and scaling to determine an average vector and simple assignment of known coefficient values. The de-warping map can be used to generate a de-warped version of the image.05-13-2010
20100124362DETECTING IMAGE QUALITY DEFECTS BY MEASURING IMAGES PRINTED ON IMAGE BEARING SURFACES OF PRINTING DEVICES - Systems and methods for implementing use of customer documents in maintaining image quality or image quality consistency of printing devices are provided. The system may include a marking engine constructed to print images on an image bearing surface of the print device; one or more color measuring devices for measured toner images formed on the image bearing surface corresponding to the one or more relevant pages, and an image analyzer configured to generate reference images and to compare measured image data with the reference images. The image analyzer may also be configured to analyze input image data for a document and to identify one or more relevant pages of the document that may provide information regarding the state of the printing system to generated reference image data. Comparisons between the color separations of the reference image data and measured image data images may be realized for determining defects.05-20-2010
20100177330JOB-SPECIFIC PRINT DEFECT MANAGEMENT - A print defect management device that supports job-specific print defect management automatically assesses print job pages to determine the severity of image quality defects likely to occur on one or more selected printers. Views of identified troubled pages may be rendered to include approximations of color and image quality defects based on the original page image data, and each printer's color rendition data and defect data, thereby allowing troubled pages for one or more selected printers to be viewed prior to printing. Suggested changes may be automatically or manually applied. Once satisfied with the image quality of print job pages rendered for a specific printer, a user may submit the print job to the same printer, thereby assuring that the user's image quality expectations are met in the printed product. The device may support job-specific print defect management with both local and/or remote printers via LAN, WAN and/or Internet based connectivity.07-15-2010
20100189348SPOT COLOR TABLE COMPENSATION - Spot color tables, or spot color emulation colorant recipes are updated using information generated during a first and second process color related system calibration. Rather than separately calibrate, through trial and error, individual spot color emulation colorant recipes, information from the first and second general system calibrations is used to adjust spot color recipes. In one embodiment, processing an existing or initial spot color recipe through both a first system model and a second system model generates a device independent color difference. A colorant difference is then determined by transforming a predicted color difference according to estimated partial derivatives of aspects of the second system model, wherein the partial derivatives relate changes in colorant amounts to changes in parameter values of a machine independent color space.07-29-2010
20100265522SYSTEMS AND METHODS FOR FORMING A TINT OF A SPOT COLOR - Systems and methods are provided for rendering tints of spot color objects or target colors between a spot color and a second color in image forming devices. In particular the systems and method provided allow for a sweep of a spot color to be rendered accurately, without discontinuities when transitioning from the tint to the solid spot color. The systems and method will prevent discontinuities even if the solid spot color has been modified by a user.10-21-2010
20100284615SPATIALLY BASED TRANSFORMATION OF SPOT COLORS - Colorant recipes for spot colors, or colors associated with vector graphic objects, are transformed to compensate for spatial variation in a rendering device. Inverted Jacobians of color production performance can be used to transform color deviations into colorant recipe changes. The colorant recipe changes are applied to original colorant recipes to provide the transformed colorant recipes. Jacobians can be determined by exercising a system model according to perturbations of the colorant recipes. Alternatively, test patches or strips based on perturbed original colorant recipes can be rendered and measured and the Jacobians can be based on such measurements. Alternatively, spatially dependent tone reproduction curves can be used to transform the colorant recipes associated with the vector graphic objects. Image processing systems can include a spatial variation information determiner, a spatial compensation information determiner and a colorant recipe transformer.11-11-2010
20100310272TWO-COLOR IOI DRUM MODULE ENABLING N-COLOR MONOCHROME, HIGHLIGHT, FULL COLOR, PHOTOTONE COLOR AND EXTENDED COLOR ARCHITECTURES - A xerographic marking device includes an intermediate transfer unit, a media transport path and at least one two-color image-on-image (IOI) drum module. Each two-color IOI drum module includes in a process order around a photoreceptor; a) a first charging unit; b) a first exposure unit; c) a first development unit; d) a second charging unit; e) a second exposure unit; and f) a second development unit, wherein the intermediate transfer unit receives a first toned image and a second toned image from the photoreceptor in a single transfer and transfers those toner images to print media to produce a toned image on print media. In various embodiments, specific color pairings are provided.12-09-2010
20110032544Optimal patch code design via device characterization - A method for optimally using color patch codes or color barcodes for transmitting machine-readable information, via device characterization, is disclosed to comprise characterizing a printing device and optionally a sensing device for identifying a number of recognizably spaced printer output colors; deriving a code book, by relating the printer output colors and their corresponding input values to information elements; and using the code book for encoding and decoding the information to be transmitted. The recognizably spaced printer output colors are in terms of a color space relevant to a color patch code or color barcode sensing device, and are related to the corresponding marking device input values.02-10-2011
20110032546SYSTEMS AND METHODS FOR ESTIMATING THE COLOR OF COATED PRINTS - A method for estimating the color of a coated print includes: measuring the color of an uncoated print with a color measuring device; and estimating the color of the print when coated by a coating process based on the uncoated color measurement using a function that correlates uncoated color measurements and coated color measurements; and adjusting at least one parameter of the printing process based on the coated color estimation. The correlating function may be derived by measuring the color of a plurality of uncoated color patches; measuring the color of the plurality of patches after the patches have been coated by the coating process; and correlating the color of the coated patches with the uncoated patches based on the coated and uncoated color patch measurements.02-10-2011
20110032573System and Method of Halftone Printing of Image Spot Colors Using Ranked Ordered Pairing of Colorants and Halftone Screens - Systems and methods of halftoning an image for extended-colorant printing image spot colors are provided which perform a quality ranking of a plurality of periodic halftone screens to be used in halftoning the image and an objectionability ranking of the colorants used to produce the one or more image spot colors. Halftone screen-to-colorant assignments are then made using a ranked ordered pairing of the ranked screens and ranked colorants. The image is halftoned using these assignments and the results can be printed or saved for future printing. Pixel tags can be used to identify the ranked ordered halftone screen-to-colorant assignments.02-10-2011
20110096330MINIMIZING SPECTROPHOTOMETER IMPACT ON SPOT COLOR ACCURACY - Differences between an offline spectrophotometer and an inline spectrophotometer can result in differences between a hardcopy target color and a printed reproduction of that color. The inline spectrophotometer is inside of a printer and configured to measure printer output. As such, the inline spectrophotometer cannot conveniently measure the hardcopy target color. A printing error or an instrument offset can be determined and passed to a color correction module that updates the device dependent color specification associated with the given spot color. This color specification may be stored, for example, in the printer controller, and used when a document subsequently calls for that spot color, thereby providing accurate color reproduction from that particular printer incorporating that particular inline spectrophotometer.04-28-2011

Patent applications by Edul N. Dalal, Webster, NY US