Abstract: A printing apparatus comprises a processor comprising registers, and a memory configured to store image data. The processor is configured to load portions of the image data into the registers and perform toner explosion compensation on the portions of the image data loaded in the registers, excluding image data loaded in boundary positions in the registers.

Abstract: Methods and apparatus are provided for electronically trapping a selected digital color image pixel. A plurality of pixels that surround the selected pixel are identified, a colorant value of each of the surrounding pixels is compared with a corresponding colorant value of the selected pixel, one of the surrounding pixels is identified to control trapping of the selected pixel, and the selected pixel is trapped based on a relationship between a colorant value of the selected pixel and a corresponding colorant value of the identified controlling pixel.

Abstract: An image processing method for adding noise-like texture to the print through the manipulation of halftone screens. The method injects noise into halftone thresholds arrays rather than directly into the image. The method operates by creating a halftone threshold array of suitable size to support the desired noise characteristics. A textured pattern of a corresponding size is created having the desired noise characteristics and boundary transitions. The texture pattern is applied to the halftone threshold array by an amount determined by a noise amplitude control curve. The incoming contone image is then processed with the modified halftone screen.

Abstract: A method includes receiving a plurality of objects included within a print job. A first object of the plurality of objects and a second object of the plurality of objects are processed to define a first overlapping region between the first and second objects. The first object is modified to remove the first overlapping region, thus generating a modified first object.

Abstract: A printing method includes the step of printing an image of a plurality of pixels by discharging a plurality of size-varying ink droplets each representing a tone of the corresponding pixel.

Abstract: A method of controlling a printer to print of an image, the printer having a predetermined marking material printed dot size, the method comprising the steps of rasterizing the image and defining halftone super pixels within the image, calculating the average density of the marking material within the super pixels, selecting a pattern for marking the pixels within the super pixels as a function of the printed dot size so as to expand the distribution of printed densities printable by the printer.

Abstract: A method, associated software and resulting printing plate having both solid and halftone areas comprising ink cells. Ink cells may be provided in the solid areas according to a first pattern with a first density and size of cells per unit area, and in the halftone areas superposed on selected numbers of halftone dots. The selection of halftone dots with superposed ink cells may be according to a second pattern with a second density and size of cells in the halftone area that is a function of halftone dot size and that may or may not be be related to the first pattern.

Abstract: An image processor includes: memory storing data including pixel values; memory storing dither matrixes corresponding to dot size and having cells with individual threshold values; a generator generating quantized data including dots corresponding to cells by comparing the data with a dither matrix, and showing that a given sized dot is formed; a calculator calculating a duty ratio of first sized dots to second sized dots based on quantized data; a determining unit determining whether the duty ratio satisfies a predetermined condition; and a threshold updater updating the dither matrixes if the condition is satisfied, at least one update being based on duty ratio; the threshold values being to: form larger dots around the dither matrix center; decrease dot size as a distance between a cell and the dither matrix center increases; and decrease dot density as the distance between a cell and the dither matrix center increases.

Abstract: The present invention is directed to a system and method for halftone screening. A system for halftone screening includes means adapted to receive image data having a desired number of tonal levels representative of a continuous tone image and means adapted to compress the received image data from a desired number of tonal levels to image data having a lesser number of tonal levels. The system further includes a memory including a look-up table, the look-up table including each of the lesser number of tonal levels and an array containing screen frequency data for each of the lesser number of tonal levels. The system still further includes means adapted for communicating the image data containing each of the lesser number of tonal levels to the look-up table, whereby corresponding screen frequency data is output therefrom.

Abstract: Uneven image density produced by photoreceptors, in which uneven electrification and sensitivity coexist, is limited economically and space efficiently. For each segment of the surface of the photoreceptor, individual memorizing of slope information K1 defining the slope of when a pixel gradation is approximately linear-transformed into exposure amount and, based upon K1 per segment, individual transforming of pixel gradation into the exposure amount (individual exposure amount transformation) is performed.

Abstract: An image forming apparatus, for forming an image with using distributions of two or more types of dots having different densities per unit area in a same hue, including: a threshold value matrix; and a dot formation determining section for carrying out comparison between a pixel value at a target pixel in the input image and a threshold value corresponding to the target pixel in the threshold value matrix, and for determining, whether to form or not to form any one of the two or more types of dots, wherein threshold values in the threshold value matrix are configured so that a frequency of dot formation is lower, for gradation regions in which a dot density of any of the two or more types of dots is low and/or high, than that for gradation regions in which the dot density is in average level.

Abstract: Method, apparatus and program product generates a threshold array that contains at least one halftone cell having overlapping or dissimilar dots.

Abstract: The technique of the invention sequentially supplies dot data to multiple dot formation elements, which are actuated to create dots simultaneously on multiple pixel arrays arranged at preset intervals, and thereby completes a resulting output image on an output medium. The procedure temporarily stores received dot data in a memory, reads out only dot data of the multiple pixel arrays, on which dots are to be created simultaneously by the multiple dot formation elements, converts the read-out dot data into high-resolution dot data, and supplies the converted high-resolution dot data in an order of actual dot formation to the multiple dot formation elements. Dots are sequentially created according to the supplied high-resolution dot data to give a high-quality image. Only the dot data of the multiple pixel arrays, on which dots are to be created simultaneously by the multiple dot formation elements, are set to the current object of resolution enhancement.

Abstract: Various exemplary embodiments include an electrostatographic printing apparatus and a method of correcting one or more associated uniformity profiles. In various exemplary embodiments the apparatus includes first and second actuators. In various exemplary embodiments the method includes measuring an image and generating at least one corresponding TRC, generating a charge profile, subtracting a reference patch density from a patch value to obtain a difference profile, converting the difference profile to a ROS intensity profile and an LED intensity profile, and iteratively repeating the steps of measuring, generating, subtracting and converting until within an acceptable range.

Abstract: A computer program and method for generating from a 1-bit image data file a multiple-bit image data file, which, when displayed on a computer display screen, resembles an image that would appear on an output medium as a result of an output device printing the 1-bit file, the program being operable to carry out, and the method comprising, the steps of: receiving a 1-bit image data file and first and second values that characterize actual regions of the output medium that would be marked by the output device when printing single and consecutive “on” pixels of the 1-bit file; calculating from the “on” pixels and the first and second values, proportions of corresponding notional rectangular regions of the output medium that would be marked by the output device when printing the “on” pixels; and setting values of the pixels of a multiple-bit image data file according to the calculated proportions.

Abstract: For obtaining a color reproduction range of a printer closer to the color reproduction range of the positive film, a mere addition of a specific color recording material in the same manner as the recording materials of other colors is insufficient, and, for a specific color showing a large gap from the color reproduction range of the positive film, an application amount different from that of the recording materials of other colors is required for such specific color, in consideration of color developing property. Therefore, in case of forming an image on a recording medium with recording materials of basic colors of cyan, magenta and yellow and recording materials of specific colors different in hue from such basic colors, a maximum application amount per unit area is made larger in at least a recording material of specific color than the application amount of the recording materials of the basic colors.

Abstract: If an ink for a particular color (for example, red) having an excellent color developing characteristic is used in addition to inks for three primary colors of subtractive color mixture, the high color reproducibility is to be maintained for a long period. To accomplish this, at least one (for example, a yellow ink) of the inks of two colors between which the hue angle of red, included in the three primary colors, is sandwiched is applied to an area of a printing medium to which a red ink is applied so that the inks overlap each other. Thus, the yellow ink, having a high weatherability, is applied to an area on the printing medium to which only the red ink, having a low weatherability, is otherwise applied. It is therefore possible to improve the weatherability while maintaining the color developing characteristic at a high level.

Abstract: To enable a necessary image data to be easily found out based on image sizes of a plurality of index images displayed in a list format and to enable contents of original images displayed as index images to be easily understood, in the case of generating an index image of an image data having an original image size larger than a standard size, a rate of reduction to the original image is increased so that the entire index image is accommodated in an index image display area while maintaining a relative dimensional relationship with index image sizes of image data having other original image sizes.

Abstract: A method for printing images on a substrate wherein the image has a textured, three-dimensional appearance is described. The printing method comprises printing a graphic design consisting of very fine lines having varying width, shape and orientation. This process is effective on the first surface of a pre-metalized substrate and on the second surface of a clear substrate. The lines are printed using an ink which even after drying or curing has a thickness (height above the film) to produce the desired textured effect. A layer of reflective ink is then printed over the entire boundary of the printed substrate, including over the clear ink. A protective layer of pigmented ink may then be printed over the reflective ink to protect the decorative substrate from abrasion. This printing process method may be used to make labels (both flat and formed) for any decorative application.

Abstract: A method for converting an original halftone bitmap image to a color converted halftone bitmap image. A set of asymmetrical morphological filters is provided. The original halftone bitmap image is segmented into blocks and for each block: apply the set of morphological filters to the original halftone bitmap image to produce a set of modified halftone bitmap images; estimate the percent dot area of the original halftone bitmap image and the set of modified halftone bitmap images; a predetermined dot-gain to the percent dot area of the original halftone bitmap image to produce a modified percent dot area; select the modified halftone bitmap image whose percent dot area is closest to the modified percent dot area to produce a block of the color corrected halftone bitmap image; and replace the original halftone bitmap image with the combined blocks of selected modified halftone bitmap image.

Abstract: In a computer generation of a dither mask for conversion of a continuous-tone image into a halftone image, a pixel array having a size in accordance with the dither mask is partitioned into blocks. Initial pixel values are determined such that the occurrences of pixel values will be substantially uniform in the blocks. A pair of exchange target pixels are selected at random from the pixels in one of the blocks and function values of a predetermined evaluation function that indicates a characteristic of the pixel value configuration of the pixels in this block are computed for the two cases where pixel values are exchanged among the exchange target pixels and where not exchanged. These function values are compared to judge whether exchange should be performed.

Abstract: A digital halftoning technique for controlling a spot function is disclosed. A method for generating a spot for use in halftoning according to the present invention includes defining a spot function that combines two functions selected to provide a predetermined spot shape for use in a halftone cell and scaling the spot function using a scaling function that varies according to a value of a first and second spot function ordinate. Asymmetric modulation of spot functions is used to control the touching of adjacent spots, and to change the shape of the spots with the gray region.

Abstract: A method for compressing/restoring image data free from degradation of image quality caused by compression/decompression, a method for compressing image data at high compression ratio, and its restoring method are disclosed. In the image data compressing method, image elements contained in a digital image read from a sheet of paper are extracted (S02), each of the extracted image elements (51-53) is subjected to data compression by a compression method corresponding to the type of the image element (S03-S05), and the compressed image element data (54-56) are stored.

Abstract: To enable a necessary image data to be easily found out based on image sizes of a plurality of index images displayed in a list format and to enable contents of original images displayed as index images to be easily understood, in the case of generating an index image of an image data having an original image size larger than a standard size, a rate of reduction to the original image is increased so that the entire index image is accommodated in an index image display area while maintaining a relative dimensional relationship with index image sizes of image data having other original image sizes.

Abstract: A method for generating a dispersed cluster screen defining a stable environment for printing an image is provided. The method initiates with generating a pattern of cluster centroids. Then a cluster growth sequence is defined. Next, a cluster is grown around the cluster centroid according to the cluster growth sequence. A computer readable medium having program instructions for generating a dispersed cluster screen and an image forming device configured to print an image according to a dispersed cluster screen technique are also provided.

Abstract: A printer host has a marginless printing mode designation accepting portion for accepting a marginless printing mode designation, a marginless printing condition setting portion for setting an expand printing region of a size that is larger than a size of actual printing paper to be printed, a renderer for converting drawing data, which is stored in a spool file, to a printing command so that a printer performs printing on this expanded printing region, a halftone processing portion, and a data-to-command conversion portion.

Abstract: There are disclosed a halftone dot producing apparatus in which a phase of halftone dots is freely set up in at least one color plate of the color plates. The halftone dot producing apparatus has an image pixel position deriving section for deriving pixel positions (i, j) associated with values G (i, j) of multi-tone level image data, a threshold pixel position set up section for setting up the pixel position of the associated threshold table to a position in which the pixel position is shifted by the phase (?i, ?j), a threshold table selection section for selecting the threshold table, a threshold set up section for setting up a threshold associated with the pixel position of the threshold table in accordance with the selected threshold table, and a comparison section for comparing the threshold set up by the threshold set up section with the value G (i, j) to produce value D (i, j) of halftone dot image data.

Abstract: An image data of M-gradations in a pixel is converted into multivalued image data of N-gradations (M>N>2) in a pixel. A remarked pixel converted into the multivalued data is determined whether to be a predetermined gradation TJ (N>TJ>2) in which a tone jump occurs. When the remarked pixel converted into the multivalued data is determined to be the predetermined gradation TJ, it is determined whether a pixel of the predetermined gradation TJ exists in pixels being adjacent to the remarked pixel. When the pixel of the predetermined gradation exists, the gradation of the remarked pixel is changed to the gradation other than the predetermined gradation so as to prevent the tone jump, and an average density after multivalued image data conversion is preserved.

Abstract: An electrophotographic apparatus reproduces a picture by expressing a gradation of the picture by use of halftone spots which are each formed by dot pictures within a plurality of pixels. The electrophotographic apparatus has a picture reproducing engine for forming the dot pictures by attaching toner to virtual dot areas each within the pixel, and an image processing unit for causing (i) growth of halftone spots of a first group in a first data range of input image data to increase a gradation of the dot pictures, and (ii) growth of halftone spots or a second group in a second data range of the input image data, which is adjacent to higher gradation level side of the first data range to further increase the gradation of the dot pictures. The gradation of the dot pictures is simply increased by the image processing unit without decrease at a boundary between the first and second data ranges.

Abstract: A method for color correcting an original halftone bitmap image by a predefined color correction function to produce a color corrected halftone bitmap image comprising: providing an original halftone bitmap image; estimating the dot area percentage of the original halftone bitmap image in a set of sub-image blocks; calculating an aim dot area percentage, based on a predefined color correction function, for each sub-image block in the original halftone bitmap image, calculating the number of halftone bitmap image pixels to convert to on or off states to produce a modified original halftone bitmap image that has the aim dot area percentage where said value is designated by N, for each sub-image block in the original halftone bitmap image, and converting N pixels in the original halftone bitmap image to either on or off states depending on whether the aim dot area percentage is greater or less than the dot area percentage of the original halftone bitmap image respectively, for each sub-image block in the origina

Abstract: Disclosed are an image processing apparatus that can decrease image quality deterioration caused by misjudgment of a halftone-dot area when its resolution is beyond an appropriate range etc., in the case where judgment of a halftone-dot area is based on the number of isolated pixels present in a predetermined area, and an image forming apparatus that utilizes the image processing apparatus. A white isolated pixel detection unit 442 (and a black isolated pixel detection unit) includes a plurality of filters 4421 and 4422 that each can detect an isolated pixel in a halftone-dot of a different size. When output is made indicating that a target pixel is an isolated pixel detected by at least one of the filters, the target pixel is judged to be an isolated pixel.

Abstract: An image recording apparatus (2000) is disclosed, which comprises forming elements (2002) for forming an image, a memory (2006) indicating relative desirability of utilising the forming elements (2002) for forming the image, and processing means (2008) for computing image recording signals using input image signals (2012) and the stored data. The use of a particular forming element is thereby biased dependent upon the relative desirability data of other forming elements, the corresponding input signal for the particular forming element, and a term for the particular forming element.

Abstract: Image content may be generated in high resolution by performing raster operations, and half-toning is then performed on the image content. Due to such a sequence, a substantially consistent image may be generated on different printers irrespective of the degree of half-toning. Another aspect of the present invention enables the computation requirements to be reduced by storing in a temporary buffer the image data (paint, destination, source) used multiple times.

Abstract: The present invention reduces the granularity of the dots for the entire density range by optimally setting formation amounts of a low-density dot and of a high-density dot per unit area. For this purpose, the formation amounts of the low-density dot and of the high-density dot in accordance with the density level are determined in such a way that as the density level rises, the formation amount of the low-density dot is gradually increased up to a first peak amount (200%) and, after reaching the first peak, gradually decreased, and in a range of density levels higher than a predetermined density level at which the low-density dot is formed to a specified amount (200%), as the density level rises, the formation amount of the high-density dot is gradually increased up to a second peak amount (100%) smaller than the first peak amount.

Abstract: A dot gain calibration system comprising a dot gain measurements database, a network for communicating data between the database and at least one printing location, a dot gain measurement device at the printing location for measuring dot gain on a printed sheet and communicating the measured dot gain, a tone reproduction curve generator configured with an input to receive current printing parameters and required target values from the printing location and information from the database, therefrom to generate tone reproduction parameters to be used in printing to compensate for dot gain.

Abstract: A system and method for scaling and enhancing color text images utilizes a binary scaling and text enhancing technique by first converting an input color text image to a binary image, i.e., black-and-white image. The scaled and text enhanced image is subsequently converted back to a color image by selectively inserting colors into the binary image to produce a color text image that has been scaled and text enhanced. The conversion of the input color text image to a binary image allows the system and method to use one of a number of conventional binary scaling and text enhancing techniques.

Abstract: A combined dot density and size modulation system uses dispersed dot halftoning in conjunction with dot size modulation to produce a halftone image in which both the density and size of the dots are modulated to control overall gray level. The dot density and size modulation system offers advantages over pure dot density modulation systems or pure dot size modulation systems because it allows an extra degree of flexibility which can be used to increase the visual quality of the halftoned pattern and/or increase the robustness of the halftoning to printer artifacts and variations. An input pixel value is used to independently produce a dot density value and a dot size value. The dot density value and dot size values may be obtained from, e.g., look up tables that have been optimized for print quality and printer stability. Dispersed dot halftoning is used to provide a halftone value for the desired pixel location using the dot density value. The dispersed dot halftoning may be, e.g.

Abstract: An electrophotographic image forming apparatus uses a halftone spot consisting of multiple dot images formed in pixel areas so as to represent a gray scale and to reproduce an image. It has a halftone processor for generating image reproduction data for each pixel by referring to a transformation table wherein gray level data for the image and correlated image reproduction data are stored.

Abstract: A circuit and method for multi-bit processing of a gray scale image in a printer. In the multi-bit processing circuit, a divider divides the gray component value of each pixel in a multi-bit image by the resolution of the printer and outputs the quotient. A remainder calculator outputs the remainder of the division for the input of the gray component value. A half-tone table stores half tone values corresponding to thresholds for pixels. A comparator compares the remainder with a corresponding threshold half tone value received from the half-tone table and outputs a binary bit according to the comparison result. A position controller controls the half-tone table to repeatedly output the threshold half tone value of each pixel. An adder adds the quotient received from the divider to the gray component of the binary processed output of the comparator, pixel by pixel and outputting a multi-bit dithered image.

Abstract: When one-to-one correspondence is made between each pixel of an original image and each element of a threshold matrix, a density of each pixel in an output image is represented by binary or multivalue, and a dot pattern of which the size corresponds to the threshold matrix is divided into small blocks, the threshold matrix is created such that the number of dots in each of all the blocks is made equal in all gray levels, the dot patterns in the plural blocks are made mutually the same in all the gray levels, and at a boundary of the blocks where the dot patterns are made mutually the same, the dots are increased while taking conformity of the dot patterns, or the threshold matrix is created such that order of dot increase is controlled between the blocks where the dot patterns are made mutually the same and the other blocks.

Abstract: The data required to specify an image which is to be printed by a printing device, such as an ink-jet or laser printer, can be substantially reduced by omitting the data specifying the dot size or amplitude modulation (AM). Instead, the processor of the printing device determines the dot density in the immediate vicinity of each dot and, from that density measurement, calculates the appropriate dot size and modulates the dot size accordingly when driving the print head or print laser.

Abstract: Disclosed is a method, system, and program for reducing toner in an image comprised of raster pel data. A determination is made of pels surrounding subject pels. For each subject pel, a sub-pulse width power is generated to charge a sub-pel region within the subject pel based on a pattern of the surrounding pels of the subject pel. Further, for each subject pel, position information is generated indicating an alignment of the sub-pel region in the pel. The position information is used to position the sub-pel region produced by the sub-pulse width power in the pel.

Abstract: An image processing apparatus includes an edge detecting unit which identifies an area of given image data as a gradation sequence area and a character/line art area and which outputs edge information of the character/line art, a level converting unit which generates a strength modulation signal so as to emphasize an edge of the character/line art area, a laser driver which outputs a laser drive signal in order to form a picture dot larger than a standard size in response to the strength modulation signal. Further, according to the present invention, it is possible to print an image with emphasizing an edge portion of a character/line art by a laser printer.

Abstract: A printer-system for printing or recording images using a plurality of dots having different densities. The printer system includes a head for producing at least 2 different types of dots having different densities per unit area, an input unit for receiving input tone data with respect to each of the pixels in an original image, a threshold value storage unit for storing threshold values, a multi-valuing unit for determining the on-off state of a dot and the type of the dot to be created at each pixel, and a dot creation unit for driving the printer head. Print image quality is degraded for example when, around any specific input tone value, there are abrupt changes in the number density of large dots to small dots. The multi-valuing unit, employing error diffusion techniques, changes the threshold values for selecting the type of dot printed to control the relative density of large dots at each input tone value and thus regulates the print image quality.

Abstract: An image-writing device writes a dot image onto an image-receiving body in such a way that the dots align at a certain screen angle. The dots are written by an array of writing elements such as light-emitting diodes. The image-writing device has a memory that stores compensation parameters that compensate for non-uniformity of the writing elements. The compensation parameters are also calculated to produce dots with approximately uniform widths as viewed in the screen-angle direction. When driven according to the compensation parameters, the writing elements produce a dot image that is comparatively free of dot-width irregularities aligned in the screen-angle direction, which is the direction in which such irregularities are most noticeable.

Abstract: This invention relates to an ink jet system (10) and to a corresponding method of use suitable for rendering the printing characteristics homogeneous upon changes in working conditions, such as the type of printing medium, inks and ambient conditions. The object is attained through optical means (24) suitable for detecting the quantity of light reflected by appropriate patterns and a control unit (21) suitable for processing the data corresponding to the quantity of light reflected in order to identify the real dimensions of the ink droplets (dot size) on the printing medium and for transmitting them to the print management programs or print drivers (67b). The system (10) and method guarantee total independence from the working conditions, with the result that the images printed will be uniform no matter what the conditions.

Abstract: A high addressable multibit screening device and method for use in a PDL interpreter environment achieve improved printing resolution and quality. A PDL interpreter receives a PDL document from a host source, which identifies one or more objects that can be fully toned (black) or partially toned (line art or images). Each of these objects can be processed differently. Fully toned objects are processed within the interpreter and directly output in a predetermined output. Partially toned objects are sent to a high addressable screening module within the interpreter for processing prior to outputting in a desired output format. The high addressable screening module screens the partially toned objects to obtain multibit screened data for output.

Abstract: An optical printer has a DMD as a spatial light modulator. An optical image corresponding to a picture frame is projected from the DMD onto a photographic paper in a variable size to print the picture frame in a designated print size. When a maximum print size is designated, image data stored in three color image memories is entirely converted into mirror drive data for driving all micromirrors of the DMD in accordance with the image data. When a smaller print size is designated, the image data is thinned to reduce the image data size in correspondence with the smaller print size. Also a smaller area of the DMD is selected as an active area in which micromirrors are driven in accordance with the thinned image data, to print a picture in the smaller print size.

Abstract: An apparatus for generating a high quality image from a digital video signal includes a system for gamma correcting the digital video signal with a digital look up table and for converting the resultant digital signal to an analog video signal. Another circuit generates a triangular wave reference pattern signal and a comparator compares the analog video signal with the triangular wave reference pattern signal to form a pulse-width-modulated signal. A raster scanning print engine producing, for example, a laser beam, scans over a recording medium in accordance with the pulse-width-modulated signal, thereby forming an image of high quality on the recording medium of a print engine. This apparatus can also be used with an analog video signal by first converting the analog video signal to a digital video signal with an analog to digital converter.

Abstract: A multi-tone image processing method and apparatus in which mutually dissimilar tone levels are realized by changing the additive condition of recording energy by means of different recording positions, even when the number of recording operations within a specific range is identical. For example, in an electrophotographic apparatus, when the number of irradiation by a light spot within a specific range remains constant as the irradiation position is changed in the specific range, there is a change in the additive condition of the optical energy within said specific range. Thus, the area rendered visible within the aforesaid specific range also changes, thereby changing the tone level.