Abstract: Provided are a method, system, and program for generating threshold values in a dither matrix. A dither matrix of threshold values is generated.

Abstract: A method and system of processing a document, includes analyzing a characteristic of a first pixel in a document and at least one second pixel positioned near the first pixel, classifying a value of the first pixel in accordance with the analysis, and modifying the value of the first pixel based upon the classification.

Abstract: A multiple beam printer system having N laser beams receives print job information from a print host. A rendering application uses a threshold array to generate halftone image data from the print job. The threshold array is defined based on a spot function. The defined screen is non-orthogonal and includes Y pels in a direction that is perpendicular to a scanning direction of the laser beams where Y is an integer multiple of N. A distance between screen dots in pels is preferably equal to an integer multiple of N. The screen dot may be defined by a supercell encompassing two screen dots and having an odd number of pels in a direction that is parallel to the scanning direction. The spot function may include a snap feature that snaps a screen dot to the nearest printer grid pel. The spot function may include scaling to compensate for the distortion of the non-orthogonal screen dot.

Abstract: A method and system for generating halftone tables, using a spot function, subdivides the pixels within the halftone cell of a halftone matrix into a plurality of sub-pixels, determines the value of the spot function corresponding to the position of each of the sub-pixels within the halftone matrix, repeats the subdividing and determining for all of the sub-pixels in the halftone matrix, ranks the values for the entire halftone matrix, normalizes the ranked values, generates a cumulative histogram based upon the normalized values, and stores the cumulative histogram as a halftone table.

Abstract: A method (and system) of multi-bit halftoning includes comparing values of an image to threshold values of a halftone threshold matrix, and generating output values that provide a greater than minimum level of contrast.

Abstract: A method (and system) for changing spatial resolution of an image includes systematically creating an image scaling look-up table including at least one pixel replacement pattern and applying a scaling algorithm to modify the image using the image scaling look-up table, thereby allowing a user to scale binary images with easy control of dot gain, output bit depth and other printer parameters.

Abstract: A method and system obtains a linear combination in accordance with an image processing algorithm using at least one lookup table that is indexed by at least one subset of bits from a set of pixels in an image.

Abstract: A method and system for calibrating a color input or output device by simultaneously solving non-linear and linear transformations includes minimizing any error between two sets of corresponding data set of the color device.

Abstract: Techniques for generating dither masks are provided. A dither mask is generated by selecting a sequence of at least three original patterns comprising pixels of at least one of a first color and a second color. At least two patterns are interpolated to generate interpolated patterns in the sequence between the at least three original patterns. If a pattern having at least one specified characteristic exists in the sequence, the steps of interpolating between at least two patterns, and determining if a pattern having at least one specified characteristic exists in the sequence, are repeated. The interpolation is between at least one pattern from each side of the pattern having at least one specified characteristic in the sequence.

Abstract: A halftone spot function, for determining a shape of a halftone spot as a function of the intensity of an image being printed, is generated by creating one or two line segments forming a part of the shape of the spot function or by creating a number of contour lines that are interpolated to form the function. A halftone spot pattern is generated as a number of supercells, each of which includes a number of halftone spots, each defined within a halftone spot cell by a halftone spot function, with the supercell being defined to include a number of device pixels, each of which is fully inked of left without ink, a number of spot cells in each direction, and offset distance establishing angles of the lines dividing the spot cells from one another.

Abstract: Pages of books are copied without distortion due to curvature of the page near the book binding or the distortion in a copied page is corrected using the spacing of equidistant bars on tape strips applied to the top and bottom edges of a page before copying. The tape is preferably transparent and rather narrow and easily attached to a page to be copied. The first step in the distortion correction procedure is to locate the bars at the top and bottom of the page. The distortion of the spacing between the imaged bars is computed based on the known distance between the equidistant bars. The computed distortion of the spacing is then input to a distortion correction algorithm. The output of the distortion correction algorithm generates a corrected image. This image may also optionally delete the bars so that they are not printed in the copy. The corrected image is then copied.

Abstract: A method and system embeds an image into two images by performing a digital halftoning process on a Cartesian product of color spaces.

Abstract: A method (and structure) for conducting a survey, includes, for each question in the survey, establishing a bin for each of a possible response to the question. For each bin, a perturbing mechanism is established that perturbs a content of the bin. The perturbing mechanism has a statistical parameter having a known value. An estimation for the distribution of the survey answers is obtained by averaging the perturbed contents of the bins and subtracting the corresponding known statistical parameter value.

Abstract: Nonlinear optimization is applied to resource allocation, as for example, buffer pool optimization in computer database software where only the marginal utility is known. The method for allocating resources comprises the steps of starting from an initial allocation, calculating the marginal utility of the allocation, calculating the constraint functions of the allocation, and applying this information to obtain a next allocation and repeating these steps until a stopping criteria is satisfied, in which case a locally optimal allocation is returned.

Abstract: A method, computer program product and system for detecting and compensating for color misregistration. A black/white edge or a solid color edge on a target may be scanned. A black/white edge may refer to a black image, e.g., black text, on a white surrounding background having a rapid spatial transition from black to white. A solid color edge may refer to a solid color image, e.g., solid color text, on a white surrounding background having a rapid spatial transition from color to white. A curve of gray values versus spatial pixel positions for each color channel, e.g., red, green and blue color channels, may be generated. A misregistration error may then be calculated by calculating the offset between the color channel curves. The misregistration error may then be used to calibrate the scanner to compensate for the detected color misregistration.