Abstract: A system and method for selective color-correction when applying three-dimensional texture to a printed substrate hinges either on a metric that is elicited from the image, or as determined by an operator. The metric may be associated with the human visual acuity curve for textural information. Other textural metrics may also be used.

Abstract: A method of printing with a CMYKF or specialized CMYK printer comprising the steps of characterizing the CMYK gamut of the printer, characterizing the CMYKF or specialized CMYK gamut of the printer, morphing the L*a*b* data associated with the CMYK gamut into L*a*b*(*) data associated with the CMYKF gamut with pre-selected control points, constructing a L*a*b* to L*a*b*(*) transform function in accordance with the morphing step, and utilizing the L*a*b* to L*a*b*(*) transform function for printing with the printer.

Abstract: A method and apparatus for processing gray level image data. Gray level image data is subjected to plural separate halftone screen processing to form plural separate halftone processed screen gray level image data. The current pixel is also analyzed for contrast index. In response to analysis of the contrast index blending coefficients for processing of the halftone screen modified image data is made. The respective halftone outputs of the screen processings are multiplied by the respective blending coefficient. The resulting blended halftone gray value of the current pixel as well as neighboring pixels are then subjected to a threshold criterion test to determine if this represents a substantially binary image file such as might occur in a saturated text image file. The blended halftone gray value data for the current pixel is subjected to gray level edge enhancement processing to replace certain binary pixels adjacent an edge to reduce anti-aliasing effects.

Abstract: An edge enhancement processing system and method for modifying image data at certain pixel locations to include gray scale image data so as to reduce jaggedness in the image. An adjustable threshold device establishes a binary pixel value for an incoming current gray level pixel in accordance with a thresholding criterion. An operator accessible input to the thresholding device is used by the operator to adjust the threshold value in the thresholding criterion. A current binary pixel formed in accordance with the thresholding criterion and neighboring pixels also so formed in accordance with the thresholding criterion are examined in accordance with predetermined criteria for determining adjustment of the current pixel to a gray scale value to reduce edge jaggedness of the image. Generally, adjustment of the thresholding value is made in instances where under color removal and/or gray component replacement is employed.

Abstract: A method and apparatus for processing image data representing a color separation or mono-color image includes processing the color separation image data or mono-color image data in accordance with first and second or more halftone screen processings at different screen angles and obtaining results of the processings and combining the results of the processings to generate composite image data of the first and second or more halftone screen processings. The resulting print of the composite image data forms relatively pleasing rosettes or diamond structures in the particular color.

Abstract: A method and apparatus for generating a multicolor image using halftone screens employs a dot structure dot growth pattern for one or more of the colors and a line structure dot growth pattern for at least two or more of the other colors.

Abstract: Gloss, differential gloss, and image relief of a printed image may be controlled by utilizing a combination of technologies in the appropriate manner. These technologies include the use of transparent toner overcoats, negative transparent toner masks, variable screen transparent toner screen masks, UV coaters, and post-press belt fusing. Unlike conventional systems, which may increase gloss at a cost of also increasing image relief, the present invention may produce an image having a controlled gloss, differential gloss, and image relief.

Abstract: By using a high or low viscosity transparent toner, with respect to the other color toners, and different amounts of transparent toner lay-down, the gloss of an image printed by an electrophotographic device may be adjusted. By also applying the transparent toner as a negative mask, the differential gloss of the image may be reduced while still adjusting the gloss of certain portions of the image. Further, because different gloss levels may appear different at different viewing angles, transparent toner may be laid down to encode a transparent image within the image being printed. Such a transparent image may be useful as, for example, an authentication means for a document. Additionally, by varying the gloss levels on particular aspects of a printed image, multiple images of different gloss levels, which are prominent at different viewing angles can be made, thereby, a three-dimensional image effect can be achieved on the printed page.

Abstract: A printer for printing color toner images on a receiver member of any of a variety of textures. The printer has a number of tandemly arranged electrophotographic image-forming modules respectively including a plurality of imaging subsystems to form a colored toner image transferred to a receiver member, the transfer of toner images from each of the modules forming a color print of the receiver member which is fused to form a desired color print. The image quality of the color print is produced by control of nonoperational co-optimization of fusing parameters and imaging subsystem parameters enabling printing on the variety of textures of receiver member.

Abstract: A copier or a printer 10 includes a controller 16/30 with a rendering algorithm that groups sets of adjacent pixels into sets of adjacent cells where each cell corresponds to a halftone dot of an image. The algorithm operates in conjunction with a gray scale printhead 22. In sending data to the printhead, the controller 16 parses a scanned image and set the exposure for each pixel in accordance with a growth and density program. The algorithm selectively grows halftone dots from zero size to a desired size equal to or less than a maximum size. It repeats this step for the rest of the pixels until the cell is at its desired size and at an initial density. If a higher density is desired, the algorithm selectively adjusts the fully grown cells by sequentially increasing the level of exposure of each pixel in the cell. The image is developed with developer including a hard magnetic carrier and toner.

Abstract: In an electrostatographic recording apparatus and method of forming images on a charge retentive surface such as a photoconductive member using a single writer source, the surface is uniformly charged by a corona charger to a predetermined voltage potential level. An image frame is then exposed on a pixel by pixel basis with varying amounts of exposure by the source for at least some pixels to form a tri-state type of latent image on the image frame including a charged area developable (CAD) latent image having at least some exposed pixels at various different sub-levels of exposure within the CAD latent image, a discharged-area developable (DAD) latent image having at least some exposed pixels at various different sub-levels of exposure within said discharged area developable image, and a background area The DAD and CAD latent images are then developed with toners of two different colors by two different developer sources.

Abstract: A method and apparatus of reproducing an image in which an original image is scanned to produce a digital representation of the original image as a plurality of original pixels regularly located within the original image and each having a grey level value. Replacement pixels randomly located within boundaries of the original image are generated. The grey level values of the original pixels are interpolated and an interpolated grey level value is assigned to each of the replacement pixels. A reproduction of the original image is generated using only the replacement pixels and their assigned interpolated grey level values.

Abstract: A method and apparatus for reproducing an original image includes a scanner or other image source for generating digitized raw image data for each pixel of an image. For each pixel, the raw image data is transformed into a rendering gray level value by comparing the raw image data value with threshold values from a threshold mask set. There are various threshold mask sets that may be used in accordance with a dot type that is selected based on a calculated local contrast index. The dot type being either a mixed dot type or one of a fixed threshold or a partial dot type. A printer or display is controlled to print the digitized image signal by rendering the dot regions in accordance with the selected dot type for each dot region, so that an original image that may contain different types of image regions is satisfactorily reproduced.

Abstract: A method and apparatus for processing image data representing plural colors for output to a color display device such as a printer or soft display. A block of digital image data signals is generated representing rasterized image data of at least two colors. The block of digital image data is compressed and stored in a compressed form. The compressed image data is then expanded losslessly and output to a color display device.

Abstract: A method and apparatus for reproducing an original image includes a scanner or other image source for generating digitized raw image data for each pixel of an image. For each pixel, the raw image data is transformed into a rendering gray level value by comparing the raw image data value with threshold values from a threshold mask set. There are various threshold mask sets that may be used in accordance with signals related to a toner particle size.

Abstract: A method and apparatus for reproducing an original image includes a scanner or other image source for generating a digitized raw image data for each pixel area of an image. For each pixel the raw image data is transformed into a gray level rendering value pixel by comparing the raw image data value with threshold values from threshold mask sets. Tone adjustment means is provided for generating a tone corrected rendering gray level pixel value for each pixel. A printer or display is controlled to print the digitized image signal by rendering the dot regions in accordance with the tone corrected gray level rendering pixel value. Thus after a print is made a tone correction adjustment maybe made and in response to this tone adjustment a new print can be made using rendering image data in buffer memory without the need for rescanning of the image.

Abstract: A method and apparatus for processing image data of pixels to be rendered for efficient storage in a memory or efficient transmission wherein a grey level value of a rendered pixel is represented by multiple bits including a most significant bit (MSB) and a least significant bit (LSB). The method and apparatus provide for modifying of the density values of successive pixels in accordance with an error diffusion operation. The modified density values are then subject to a thresholding operation wherein the thresholding operation employs position of a pixel to determine the digital value of the LSB of the rendered pixel. There is thereby provided a pattern structure to the LSB data. The rendered pixel values may then be compressed to provide for efficient storage in a memory or for efficient transmission over a communication pathway.

Abstract: Apparatus for producing a screen halftone image provides for segmentation of images by optical density, busyness, segment size, and/or propensity to contouring; and for printing the segments which have high optical density, are more busy, and/or have a lesser propensity to contouring at a relatively high screen frequency; and for printing segments which have low optical density, are less busy, and/or have a greater propensity to contouring at a relatively low screen frequency. Both screen frequencies are printed at the same apparent screen angle to reduce texturing. Small segments are assigned the same screen frequency as the surrounding segment.

Abstract: A method and apparatus for modifying a digitized image in which the digitized image is received as input pixel values for a plurality of pixels, first selects an unprocessed one of the pixels to be a current pixel. The current pixel is modified by adding a total error value and a screen frequency component to the input pixel value of the current pixel to produce a modified current pixel value. The modified current pixel value is thresholded to produce an output pixel value for the current pixel, which becomes a processed pixel. The output pixel value is then mapped into an image range, and a total error incurred for the processed pixel caused by the mapping is determined. The total error incurred is distributed to at least one of the other of the plurality of pixels that is an unprocessed pixel. The procedure is repeated for each pixel in the plurality of pixels to provide a modified digitized image.

Abstract: A method and an arrangement for reproducing an original image that has one or more different image type regions. The arrangement has a scanner which scans and digitizes the original image into pixels, a controller coupled to the scanner to receive the digitized original image, and which produces a first signal corresponding to a gray level halftoned representation of the digitized original image, and a printer coupled to the controller to receive the first signal and which produces a gray level halftoned reproduction of the original image. The controller operates the printer in a default mode when the original image contains a text region or a halftone region, this default mode including either contour suppression applied to every pixel of the original image, or using an output screen that is a higher frequency than a screen of the original image.