Abstract: A comparison is made between image data and a predetermined image pattern and data on a specific area is extracted from the image data based on the comparison result, and dot data is added at a position away from an end of the specific area subjected to the signal-level reduction by as much as a predetermined distance.

Abstract: A method for estimating three-dimensional structure from a two-dimensional image (502) includes obtaining first and second vanishing points (120, 122); comparing image patches (202) along first and second virtual lines (204, 208) extending from the first and second vanishing points (120, 122), respectively, and through a pixel; generating values for each of the first and second virtual lines (204, 208) based on the comparison of the image patches (202); accumulating the values for each the pixel in the two-dimensional image (502); and determining a corner pixel (106) based on a highest of the accumulated values.

Abstract: Before page description data are input to a raster image processor (RIPa) that plots an overprint of a shading object in process colors in the nonzero overprint mode, the page description data are converted into robustized page description data wherein minimum values of process colors are replaced with small values which are not of 0. The robustized page description data are input to the RIPa.

Abstract: A method of reducing blurring in an image of size greater than M columns by N rows of pixels, comprises deriving a blur kernel k representing the blur in the image, and deriving an inverse blur kernel k?1. The inverse blur kernel is given by (I) where h(m) is the sum of the first m terms of the series (II) ? is the Dirac delta, m is greater than 1, and h(m) is a two dimensional matrix of size M×N. The two dimensional matrix h(m) is convolved with the image over the whole image in the image pixel domain to produce an image with reduced blur. The method may be applied to a video sequence allowing the sequence of images to be deblurred in real time.

Abstract: In a method for designing a halftone screen configured to reduce artifacts in a printed image, artifacts due to a process variation resulting from printing of the image through use of a halftone screen design are modeled and the halftone screen is designed to have threshold values that substantially reduce the artifacts due to the process variation.

Abstract: A method has been developed for detecting defects in printed images. The method includes operating a printer to print a first printed image and a second image, where the second image is a duplicate of the first printed image. The method further includes generating image data that correspond to the first printed image and the second printed image, and identifying image defects using differences between the image data generated for the first image and the image data generated for the second image.

Abstract: A method for minimizing cross-process non-uniformities in solid and heavy shadow regions of printed documents is provided. The method includes marking with a marking engine an image on an image bearing surface moving in a process direction; generating profile data of the image by sensing an optical characteristic of the image in a cross-process direction; adjusting at least one control actuator of the marking engine so as to shift the characteristic of a subsequent marked image in the cross-process direction to at least a target value; and generating a spatially varying tone reproduction curve to smooth the characteristic of the subsequent marked image towards the target value.

Abstract: An apparatus and a method are described for processing and reproducing a document including both text and half-tone images without generating undesirable image artifacts. A band-pass FIR filter with a predetermined frequency response is used to transform pixels in an input image to sharpen text edge and smooth pre-half-toned areas, and perform error diffusion and cluster dot screening methods on the transformed pixels. The FIR filter has unity gain at DC to preserve image brightness. An integrated error diffused cluster-dot screening approach is used to suppress moiré and other image artifacts, while providing a robust, crisp output.

Abstract: A method and apparatus for adjusting estimated ink pile height to reduce the frequency and effects of a defect known as a halo defect. An estimated ink pile height profile of ink to be deposited on a surface in an area of image data having a foreground and a background is determined. The estimated ink pile height profile has a foreground color area including a top color component and at least one non-top color component in the foreground. Then, the estimated height profile is adjusted if the difference between the pile heights of the foreground and background is greater than a threshold condition.

Abstract: Color separation systems and methods improve color constancy and smoothness of a color lookup table (LUT) for a printer. A plurality of nodes of the LUT may be defined in colorimetric space, and the nodes out of the printer gamut may be mapped to the printer gamut surface. All possible colorant combinations are then determined that produce each node in the LUT in a device independent color space based on an inversion of the spectral based printer model. Next, a specific image quality metric combination based on a color inconstancy index (CII) and a gray component replacement (CGR) strategy is defined. And a colorant combination is determined for each and every node in the LUT based on this metric. A smoothing filter may be used to smooth the lookup table.

Abstract: This disclosure provides methods, systems and apparatus for jointly optimizing node locations and corresponding output value of a color look-up-table (LUT) associated with an imaging device. According to one exemplary method, initially a set of LUT node locations are generated by solving a first optimization problem and subsequently, a set of LUT node values are generated by solving a second optimization problem.

Abstract: An unnatural color change which occurs when combining trapping and spatial filter processing is suppressed. When image data is input, it is determined whether to perform trapping at the position of the pixel of interest of the input image data, and trapping is performed for the input image data. In addition, spatial filter processing is performed for the pixel of interest of the input data, an output of the trapping and that of the filter processing are weighted, and image data to be output is calculated.

Abstract: A 2-pixel averaging unit (101) halves an input image in the subscanning direction, and a multi-level error diffusion unit (102) performs multi-level error diffusion processing. A 2-pixel reconstruction unit (103) replaces each pixel with two pixels adjacent in the subscanning direction. A density value exchange unit (104) exchanges pixel values adjacent in the subscanning direction in each of 2×2 pixel blocks arranged in a checkered pattern in the image after replacement. High-density blocks each serving as a set of high-density dots and low-density blocks each serving as a set of low-density dots can be generated as 2×2 pixel blocks. The exposure region can be concentrated in PWM conversion.

Abstract: An image processing apparatus stores pixel data of an input image in a storage apparatus after performing resolution conversion encoding, and performs a pixel interpolation process after reading out the pixel data stored in the storage apparatus and performing resolution conversion decoding. The image processing apparatus determines, when resolution conversion encoding the pixel data of the input image, whether a resolution of the pixel data will decrease due to the pixel interpolation process, based on attribute information indicating an attribute of the pixel data, and performs processing to decrease the resolution of the pixel data in the resolution conversion encoding, if it is determined that the resolution will decrease.

Abstract: The problem of the present invention is to be capable of executing color shift correction processing also in consideration of a mechanical inclination component in an image forming device. For solving the problem, the image forming device according to the present invention comprises information processing unit, first measurement requesting unit, holding unit of curve information, notifying unit of curve information, receiving unit of a measurement pattern image, measurement processing unit, determining unit of a result of the measurement processing, and second measurement requesting unit.

Abstract: An image processing apparatus includes a dividing unit configured to divide image data into pieces of print scan image data for the plurality of print scans, a quantization unit configured to quantize the pieces of print scan image data, and a generation unit configured to generate pieces of print data for the plurality of print scans on the basis of the quantized pieces of print scan image data. In a case where a density represented by the pieces of print scan image data is a low density, the quantization unit quantizes the pieces of print scan image data so that they are mutually exclusive in the plurality of print scans.

Abstract: The technology disclosed relates to methods and devices that compensate for displacements in a pattern or deformations of a workpiece. In particular, this relates to using timing to compensate for displacements along a first axis along the scanning direction while using resampling, interpolation or a similar method to compensate for displacements along a second axis that is substantially orthogonal to the first axis. The scanning direction may be an actual direction of movement of the scanning head or it may be a direction perpendicular to an orientation of an image projected onto a workpiece.

Abstract: Aspects of the present invention are related to systems and methods for determining a skew angle associated with a document image. According to a first aspect of the present invention, a rotation vector may be estimated for at least one layer in a vertical-edge buffer and a horizontal-edge buffer. According to a second aspect of the present invention, a rotation vector may be estimated directly from the vertical-edge buffer and the horizontal-edge buffer using a fixed-sized, progressively constrained histogram.

Abstract: A method for controlling the printing of overlapping swathes, the swathes extending perpendicular to a succession of print lines; for each print line a transition is defined between one swathe and the next, with the location of the transition in the print line varying between print lines, for example varying pseudo-randomly or as a curve extending in the swathe direction.

Abstract: In a method to correct a registration error in a printing process, data of first and second images to be printed are subjected to a raster image process via which at least first and second raster graphics are generated. Control data for a print member or two respective print members are formed from the first and the second raster graphics. A recording medium is printed in a first printing process with the control data of the first image. The recording medium is subjected to a treatment via which the recording medium and the first image deform along at least one deformation axis. The recording medium is printed by the print member with the control data of the second image in a second printing process.

Abstract: A patch is printed on a printing medium, and ink discharge amount information is acquired from a colorimetric value that is acquired by measuring a printed patch. According to the information, color correction is performed on image data to be processed for printing, using a correction table that corresponds to a designated type of printing media.

Abstract: A method of providing calibration data for a printer includes printing a calibration target using the printer. The target includes a plurality of patch sets, each including a plurality of test patches, each patch having a respective color. Scanned patch data for one of the sets are received from a spot scanner. The scanned patch data values are compared to respective aims to determine a reproduction error value for the scanned patch set. A processor automatically determines which of the sets should be scanned next using the calculated reproduction error value. The process is repeated until all sets have been scanned, or until the reproduction error value is less than or equal to a selected threshold. Calibration data are automatically generated using the scanned patch data.

Abstract: A switching controller system and method for improving graininess in an image during a profile construction. A switching control strategy can be employed to construct an ICC destination profile by switching between a first controller (e.g., a 3-input 4-output controller) and a second controller (e.g., a 3-input 3-output controller) based on a color space region that requires a graininess minimization. The first controller dynamically modifies the CMYK values until reaching a subset of LAB values contained in the ICC profile. The second controller varies three colorants and holds a remaining colorant of the CMYK values until reaching the remaining LAB values in the ICC profile. Such an approach reduces the graininess and provides an improved smoothness with respect to the image during the ICC profile construction.

Abstract: A first screen group and a second screen group are stored in an image forming apparatus. In the first screen group, the first region expands with increasing gradation value based on a first rule. In the second screen group, the first region expands with increasing gradation value based on an independent second rule different from the first rule. A screen selector relocates a first portion and a second portion such that the first portion and the second portion are joined by a second region that is not a toner adhesion control target, when the first portion and the second portion are adjacent as a result of the selection of the screen in each unit region of the input image. The first portion includes the screen included in the first screen group, and the second portion includes the screen included in the second screen group.

Abstract: A method and a system with which the quality of an image derived from or addressed to a chain of appliances can be modified. Formatted information related to defects of the appliances is employed. The method and system: compile directories of sources of formatted information related to the said appliances, search automatically for the formatted information related to the appliances, and modify the image automatically by image-processing software and/or image-processing components by taking into account the obtained formatted information. The formatted information can be modified as a function of variable characteristics of the image to be processed and/or the appliances. With the method and system it is possible to process images derived from appliances that have diverse origins and that have been commercialized gradually over time. Such a method and system are applicable to processing of photographic or video images and in optical instrumentation, industrial controls, robotics, metrology, etc.

Abstract: In an image processing apparatus according to one embodiment, an edge correcting unit replaces a signal level of a target pixel with a maximum value of signal levels of a plurality of peripheral pixels when a sum of the signal level of the target pixel and the edge information is more than the maximum value, and the edge correcting unit replaces the signal level of the target pixel with a minimum value of the signal levels of the plurality of peripheral pixels when a sum of the signal level of the target pixel and the edge information is less than the minimum value.

Abstract: An optical scanning device includes a light source that emits first and second light beams, and an optical splitter to which the first and second light beams deflected by an optical deflector are incident. Principal rays of the first and second light beams incident to the optical splitter are nonparallel to each other in a plane orthogonal to a main-scanning direction. Transmitted light from the optical splitter out of the first light beam and reflected light from the optical splitter out of the second light beam are guided to corresponding scanning target surfaces, and transmitted light from the optical splitter out of the second light beam and reflected light from the optical splitter out of the first light beam reach none of the scanning target surfaces.

Abstract: Methods for reducing dimensionality of hyperspectral image data having a number of spatial pixels, each associated with a number of spectral dimensions, include receiving sets of coefficients associated with each pixel of the hyperspectral image data, a set of basis vectors utilized to generate the sets of coefficients, and either a maximum error value or a maximum data size. The methods also include calculating, using a processor, a first set of errors for each pixel associated with the set of basis vectors, and one or more additional sets of errors for each pixel associated with one or more subsets of the set of basis vectors. Utilizing such errors calculations, an optimum size of the set of basis vectors may be ascertained, allowing for either a minimum amount of error within the maximum data size, or a minimum data size within the maximum error value.

Abstract: The invention relates to the processing of a digital object that comprises: cancelling the noise of an original object (I) of a first type containing noise in order to obtain a noise-free object (J) of the first type; obtaining an object with a quasi-white noise of the first type from a difference (B) between the original object and the noise-free object; applying to the noise-free object (J) a first processing (t1) that comprises a neighboring processing for obtaining a transformed object (K) of a second type, the first processing being such that it would structure the noise contained in the original object if it was applied to said original object; applying to the noise object a second white processing (t2) for obtaining a quasi-white transformed noise object (C) of the second type; and inserting into the transformed object (K) the transformed noise object.

Abstract: An image forming system includes a pseudo-halftoning device; an image forming apparatus that forms a toner image on a recording medium; and a reading apparatus that read the toner image on the recording medium, in which the pseudo-halftoning device is such that pseudo-halftoning is performed on a target image by using a threshold matrix set including a plurality of threshold matrices, one threshold matrix for use is selected from the threshold matrix set according to a position of the target image to be used in the pseudo-halftoning performed on the target image, the threshold matrices in the threshold matrix set are identical with one another in periodic structure but different from one another only in a gradation characteristic, and a threshold matrix to be used is determined based on toner-image information data obtained by reading the toner image by the reading apparatus.

Abstract: Techniques for automatic exposure correction of images are provided. In particular, the exposure of an input image may be improved by automatically modifying a non-linear function that characterizes the luminance of shadow, mid-tone, and highlight portions of the image. The input image may be segmented into a number of regions and each region is assigned a zone, where the zone indicates a specified range of luminance values. An initial zone assigned to a region of the image may be changed in order to reflect an optimal zone of the region. Based, in part, on the optimal zones for each region of the image, luminance modification parameters may be calculated and applied to the non-linear function in order to produce a modified version of the input image that improves the appearance of overexposed and/or underexposed regions of the input image.

Abstract: A method for compensation of banding in a marking platform includes: initiating a signature learning mode; establishing a timing reference after marking modules have achieved constant velocity; marking a test pattern over multiple intervals of a lowest fundamental frequency among marking modules; obtaining image data for the test pattern from a sensor; and processing the image data in relation to the timing reference to form banding profiles for multiple banding sources. Alternatively, the method may include: initiating a cycle up stage in a phase learning mode; establishing a timing reference after marking modules have achieved constant velocity; marking a test pattern over multiple intervals of a lowest fundamental frequency among marking modules; obtaining banding image data for the test pattern from a sensor; and processing the image data with banding signatures in relation to the timing reference to form phase estimates for each banding signature. Additional embodiments are also provided.

Abstract: An image processing apparatus includes an image reading unit that reads an image of a document as color image data including pieces of color component data; a dot-component removing unit that removes dot components by smoothing each color component data; a high-frequency-color identifying unit that identifies, of colors represented by dot-removed color component data obtained by the smoothing, a high-frequency color satisfying a predetermined high-frequency condition; an individual-density-conversion-information generating unit that generates, for each high-frequency color, individual-density conversion information for converting each color component data such that a color near the high-frequency color becomes substantially the same as the high-frequency color; and a color-component-data converting unit that converts, based on the individual-density conversion information, each color component data in a part of the color image data, the part being data in which a color represented by the dot-removed color com

Abstract: An image forming apparatus includes: a storing section, an image forming section to form a measurement image to output a measurement chart, and a control section for inputting density information indicating densities at positions of the measurement image, to calculate a correction value corresponding to each position based on the density information, to store the value in association with an output condition including a screen condition indicating a screen processing at the time of outputting the chart, to determine the output condition of the image data, to read the value corresponding to the output condition, and to correct the image data based on the value, wherein the image forming section forms an image based on the corrected image data, and when no correction value corresponding to the screen condition of the input image data is stored in the storing section, the control section inhibits the correction from being executed.

Abstract: As set forth herein, computer-implemented methods and systems facilitate halftoning using boundaries and centers of a polygonal tiling with a parameterized spot function that operates within the tiles. Defining the halftone structure includes defining the polygonal tiling with a specification of the polygon boundaries and center, and setting and applying parameters of the spot function, which utilizes center-to-boundary distances. The tiling can be defined explicitly, by defining a tile structure, or providing centers, one per polygon, and vertices for the polygons. The vertices and centers are used to generate the polygon boundaries. The polygonal tiling can be regular (e.g., repetitive) or irregular, and can also be varied in a manner adapted to the image content or to data that is being embedded.

Abstract: According to the present invention, there is provided a color image forming apparatus which includes image forming units forming images, each for each color component, and superimposes the images of the color components on one another to form a color image. The image forming apparatus includes a scan line changing unit shifting the position of each pixel in a sub scanning direction for each color component of halftone image data to be processed so as to cancel a shift amount of a scan line on an image carrier in each of the image forming units in the sub scanning direction; an interpolation inhibited area determining unit determining an interpolation inhibited area in the image data; and an interpolation unit applying an interpolation process for smoothing a pixel-level shift caused by shifting of image data by the scan line changing unit to the image data excluding the interpolation inhibited area.

Abstract: Provided is a 3-colorant DOD (dot-off-dot) periodic halftone geometry used to render an image. The DOD 3-colorant halftone geometry includes a base colorant halftone screen with hexagonally tiled halftone dots arranged in a hexagonal pattern, the hexagonally tiled halftone dots having a first fundamental frequency vector Vh1, a second fundamental frequency vector Vh2, and a third fundamental frequency vector Vh3, where Vh3 is substantially equivalent to Vh1+Vh2.

Abstract: The systems and methods presented herein provide for calibrating a print engine of a printing system. The printing system prints image data on a print medium and scans the printed image data. Color values of the scanned image data are then measured and various tints of color values and their transition locations are identified. A calibration module estimates the original optical densities of the identified color value tints and generates a target optical density for each of the identified color value tints using the estimated original optical densities to determine print irregularities in the color values of the scanned image data. The calibration module then generates a halftone screen based on the mean optical densities and applies the generated halftone screen to the print engine to calibrate the print engine.

Abstract: An image forming apparatus includes DMA control units each of which is provided with DMA controllers. Each DMA controller is provided with a plurality of data buffers respectively corresponding to different addresses in a subscanning direction. Each of a predetermined number of pixel data in a main scanning direction is stored in an associated one of the data buffers. Pixel data stored in each of the data buffers are output to an image memory based on the address in the subscanning direction, which corresponds to the associated data buffer.

Abstract: A method, system, and computer program product for estimating exposure modulation in an image printing system is disclosed. The method includes determining a banding profile for an image printing system by a processor; determining an adjusted exposure modulation profile based on the banding profile using a least squares estimation by the processor; and printing an output based on the adjusted exposure profile.

Abstract: Some embodiments of the invention provide a non-linear image-enhancement method to enhance an image that includes a number of picture elements. The non-linear enhancement method adjusts the brightness value of each pixel in the image and adjusts at least one chromatic value of each pixel in the image based on the adjustment to the brightness value of that pixel.

Abstract: The invention enables creating a mark-able document for a user to mark, and recognizing and processing the user-marked mark-able document to generate an accurate user-readable result that has broad application. The application program used to create, process, and generate a printed output based on the processing includes an array of functionality to create a wide variety of mark-able documents.

Abstract: A host apparatus, an image forming apparatus, and a diagnosis method for the image forming apparatus, the diagnosis method including: storing a printing image generated from print data according to a printing command; and generating a diagnosis image for the printing image based on the stored printing image and a defect image corresponding to a predetermined defect of the image forming apparatus.

Abstract: Certain embodiments provide an image reading apparatus including: a monochrome CCD sensor including a first photo-diode array; plural color CCD sensors each including a second photodiode array; an AD converter configured to apply analog-to-digital conversion to each of analog outputs from the second photodiode array and the first photodiode array; a delay processing unit configured to delay at least one of color image data of plural colors from the AD converter and interpolate, with delayed any one or more of the color image data, a blank of image data that is to be read on a line in a sub-scanning direction; and an inter-line correction unit configured to correct, by the intervals and a set reduction magnification, a positional deviation in the sub-scanning direction between the monochrome image data and the color image data, respective timings of which are aligned on the line by the delay processing unit.

Abstract: An image processing apparatus includes a scanning unit configured to scan at least one of two surfaces of a printed material on both of which information is printed and to obtain a density image representing intensity distribution of diffuse reflection light from the scanned surface and a gloss image representing intensity distribution of specular reflection light from the scanned surface, a mask image generating unit configured to generate a mask image for the scanned surface based on the obtained gloss image, and a show-through removing unit configured to perform mask processing on the density image using the generated mask image to generate a show-through-removed image that does not include show-through information for the scanned surface.

Abstract: Methods disclosed permit the identification of frame buffer pixels for trapping. In some embodiments, flags associated with pixels in the frame buffer may be used to provide an indication of pixels for trapping. A first bit in a flag associated with a pixel may be set when the pixel is painted. In some embodiments, the method discloses a process for setting the value of a second bit in the flag to determine if the pixel associated with the flag lies on an object boundary. The pixel is identified as a candidate for trapping based on the value of the at least one flag.

Abstract: A method for predicting an appearance of a rendering by a printer of a digital halftone representation of a continuous-tone image includes calculating a predicted absorptance value of a dot of a rendered halftone of the digital halftone representation. The dot corresponds to a pixel of the digital halftone representation. The predicted absorptance value is based on a configuration of pixel values of pixels in an immediate neighborhood of the pixel, and on a weighted contribution of a pixel value of each pixel in an outer neighborhood of the pixel. The method may be incorporated into a halftoning technique. Relating computer program product and data processing system are also disclosed.

Abstract: A method of adjusting line data is provided, where a dot pattern for one line is represented by dot data indicative of dot formation and blank data indicative of no dot formation. The method includes: determining whether X or more blank data are arranged consecutively, the X or more blank data including adjacent blank data adjacent to dot data on at least one side of the dot data, where X is an integer greater than or equal to one (X?1); and converting Y consecutive blank data including the adjacent blank data into dot data if it is determined that the X or more blank data are arranged consecutively in the determining step, where Y is an integer greater than or equal to one and less than or equal to X (X?Y?1).

Abstract: A data processing apparatus for registering image data includes a network processing unit configured for acquiring image data through a network, an image correction unit for analyzing the image data, extracting a background image and a subject image from the image data, and correcting the extracted background image according to a correction condition, and a database unit for storing the corrected image data such that the image data is associated with the corrected image data.

Abstract: An image forming apparatus comprising an image forming unit that forms an image based on a processing batch, a measurement unit, which interrupts the processing batch to form a density pattern by controlling the image forming unit, and which obtains density adjustment data by measuring the density pattern, and an adjustment unit that adjusts the density of the image based on the density adjustment data. When the measurement unit performs a density measurement before formation of a first color page of a processing batch, which includes monochrome and color pages, the adjustment unit adjusts the density of each color page using new density adjustment data obtained through the density measurement performed before the formation of the first color page, and the adjustment unit adjusts the density of each monochrome page using old density adjustment data obtained before the density measurement performed before the formation of the first color page.