Abstract: Methods are provided for determining toner colors to be combined to form a target color at a location on a receiver. In one aspect, a method includes determining a fluorescent toner color to be provided at the location based upon the density and hue angle of the target color; determining one or more reflective toner colors to be provided with the determined fluorescent toner color at the location to form the target color and the amount of the fluorescent toner color is decreased as the target color density increases.

Abstract: Systems are provided for determining toner color having a processor that generates a fluorescent toner color image that when printed using a corresponding fluorescent toner will generate a diffuse fluorescent color light that reduces the extent to which noise induced variations in density in a noise evident portion of a toner print are observable. The processor further adjusts reflective toner color images used to form the toner print so that the reflective toner color images combine with the fluorescent color image to form a target color image.

Abstract: Apparatus for depositing a texture on a receiver includes a data source that provides multilevel input tint data values. A lossy compressor produces compressed multilevel tint data values from the multilevel input tint data values. A decompressor produces multilevel decompressed tint data values from the compressed multilevel tint data values. A texture memory receives those values from the decompressor and provides corresponding multilevel texture pixel data values. A print engine deposits at each of a plurality of pixel sites on the receiver an amount of texture-forming material corresponding to the respective multilevel texture pixel data value. A loader loads into the texture memory a texture set including multilevel texture pixel data values for each of a plurality of textures, and each texture in the texture set corresponds to a respective selected range of multilevel decompressed tint data value.

Abstract: A composite color toner image can be enhanced by applying a separate fluorescing toner image over it to provide an enhanced color toner image having a “pinkish” fluorescing effect. This separate fluorescing toner image is obtained using visible fluorescing dry magenta toner particles. Each of these toner particles consists essentially of a polymeric binder phase and a visible fluorescing colorant that emits at one or more peak wavelengths of at least 510 nm and up to and including 590 nm and that is dispersed within the polymeric binder phase.

Abstract: Methods are provided for automatic cross-track density correction for a print engine having a print head that forms lines of picture elements on a receiver based upon lines of pixel values. In one aspect of the method, the print engine is caused to print a first print having a plurality of different areas along a cross-track direction with target densities and data is received from which measured densities for different ones of the plurality of different areas can be determined. A line density adjustment function is based upon a functional relationship between a cross track position of different ones of the areas and a difference between the measured density and the target density at the different ones of the areas. A production print is subsequently printed according to lines of pixel values for the production print modulated by the line density adjustment function.

Abstract: One or more printers or printing systems are connected to a scanning device. Each printer includes one or more color modules that are used during a printing operation. A printer prints a target for each color module or color channel. The printed targets are then scanned by the scanning device. The printed targets may be rotated to any angle and then scanned by the scanning device. The scanned raster data is processed by a controller to detect non-uniformities in at least one density image and to generate one or more correction profiles for the printer. When an image is to be printed, one or more controllers receive the image data and use the one or more correction profiles to correct or compensate for the non-uniformities during the exposure process.

Abstract: Screened hardcopy reproduction apparatus for applying toner to a receiver using a print engine that may not apply toner uniformly, so the toner applied to the receiver has a non-uniformity. A controller receives an input pixel level and a corresponding input pixel location; a tone-reproduction unit calculates an output pixel level from the input pixel level and a corresponding output pixel location from the input pixel location; a compensator calculates a compensated pixel level from the output pixel level and the output pixel location; and a screening unit calculates a screened pixel level and a screened pixel location from the compensated pixel level, the output pixel location, and a selected screening pattern. The print engine applies an amount of the toner corresponding to the screened pixel level and the non-uniformity to the receiver at a toner location corresponding to the screened pixel location to compensate for the non-uniformity.

Abstract: Correction data is produced for density errors in prints produced using a printer. While printing a test image, the periods of rotation of one or more rotatable imaging members arranged along a receiver feed path in the printer are measured using respective period sensors. The printed test image is measured along a selected measurement direction and a reproduction error signal representing deviation from aim density is determined. For each period sensor, the autocorrelation of the reproduction error signal for the corresponding period is determined. If the determined autocorrelation exceeds a selected threshold, the reproduction error signal is decomposed at the corresponding period to extract the variation from the measured component. The remaining error signal is separated by frequency terms. The variations from the data at measured periods and the remaining error signal are used to produce a correction signal.

Abstract: A computer implemented method of producing personalized documents comprising the steps of inputting handwritten alphanumeric characters which are then mapped into at least one set of text characters. A textural document is entered into the computer and is transcribed into a set of text characters corresponding to the input handwritten alphanumeric characters. The document can be printed and will contain text in the handwriting of the person whose alphanumeric characters were used as input.

Abstract: Methods are provided for automatic cross-track density correction for a print engine having a print head that forms lines of picture elements on a receiver based upon lines of pixel values. In one aspect of the method, the print engine is caused to print a first print having a plurality of different areas along a cross-track direction with target densities and data is received from which measured densities for different ones of the plurality of different areas can be determined. A line density adjustment function is based upon a functional relationship between a cross track position of different ones of the areas and a difference between the measured density and the target density at the different ones of the areas. A production print is subsequently printed according to lines of pixel values for the production print modulated by the line density adjustment function.

Abstract: Printers are provided having a print engine having a print head that forms lines of picture elements on a receiver based upon lines of pixel values and a controller that causes the print engine to print a first print having a plurality of different areas along a cross-track direction with target densities and that receives data from which measured densities for different ones of the plurality of different areas can be determined. The controller determines a line density adjustment function based upon a functional relationship between a cross-track position of different ones of the areas and a difference between the measured density and the target density at the different ones of the areas and subsequently prints a production print according to lines of pixel values for the production print modulated by the line density adjustment function.

Abstract: Apparatus for depositing a texture on a receiver includes a data source that provides multilevel input tint data values based on a job specification. A lossy compressor produces compressed multilevel tint data values from the multilevel input tint data values. A decompressor produces multilevel decompressed tint data values from the compressed multilevel tint data values. A texture memory receives those values from the decompressor and provides corresponding multilevel texture pixel data values. A print engine deposits at each of a plurality of pixel sites on the receiver an amount of texture-forming material corresponding to the respective multilevel texture pixel data value. A loader loads into the texture memory a texture set including multilevel texture pixel data values for each of a plurality of textures, and each texture in the texture set corresponds to a respective selected range of multilevel decompressed tint data value.

Abstract: Apparatus for depositing a texture on a receiver includes a data source adapted to receive a job specification and provide corresponding texture identification data values. A texture memory receives the texture identification data values from the data source and provides corresponding multilevel texture pixel data values. A loader loads into the texture memory a texture set including multilevel texture pixel data values for each of a plurality of textures, each texture in the texture set corresponding to one or more of the texture identification data values. A print engine deposits at each of a plurality of pixel sites on the receiver an amount of texture-forming material corresponding to the respective multilevel texture pixel data value.

Abstract: Apparatus for depositing a texture on a receiver includes a data source that provides multilevel input tint data values. A lossy compressor produces compressed multilevel tint data values from the multilevel input tint data values. A decompressor produces multilevel decompressed tint data values from the compressed multilevel tint data values. A texture memory receives those values from the decompressor and provides corresponding multilevel texture pixel data values. A print engine deposits at each of a plurality of pixel sites on the receiver an amount of texture-forming material corresponding to the respective multilevel texture pixel data value. A loader loads into the texture memory a texture set including multilevel texture pixel data values for each of a plurality of textures, and each texture in the texture set corresponds to a respective selected range of multilevel decompressed tint data value.

Abstract: Compensation is performed for nonuniformity in a printer. The printer has a photoreceptor and a print head with a plurality of different light sources, each light source capable of producing a plurality of different levels of light. A plurality of stored gain control signals for each light source are related to the light output of that light source. Print job data includes screened pixel levels and a halftone screen specification. The stored gain control signals are adjusted based on the halftone screen specification. The screened pixel levels are modified using the adjusted gain control signals to provide engine pixel levels. Those levels are provided to corresponding light sources to expose the photoreceptor in respective pixel areas with light corresponding to the compensated pixel levels.

Abstract: Electrophotographic (EP) streaking compensation is performed. A tonescale is measured for each column and a per-column gain computed to compensate for variations. An adjustment tonescale is determined and a per-column adjustment-tonescale gain computed to correct for remaining error after the per-column gain is applied. The two corrections are used together to provide improved compensation quality.

Abstract: Methods of improving image quality by reducing grain and texture in a printed image are provided. According to one embodiment, a method of reducing grain and texture in an image includes the steps of providing a light color toner and a dark color toner, providing an aperiodic micrononuniformity map, using the aperiodic micrononuniformity map to determine an acceptable domain that includes a plurality of combinations of the light color toner and the dark color toner, and forming an image by selecting one combination of the light color toner and the dark color toner from the plurality of combinations of the light color toner and the dark color toner.

Abstract: Screened hardcopy reproduction apparatus for applying toner to a receiver using a print engine that may not apply toner uniformly, so the toner applied to the receiver has a non-uniformity. A controller receives an input pixel level and a corresponding input pixel location; a tone-reproduction unit calculates an output pixel level from the input pixel level and a corresponding output pixel location from the input pixel location; a compensator calculates a compensated pixel level from the output pixel level and the output pixel location; and a screening unit calculates a screened pixel level and a screened pixel location from the compensated pixel level, the output pixel location, and a selected screening pattern. The print engine applies an amount of the toner corresponding to the screened pixel level and the non-uniformity to the receiver at a toner location corresponding to the screened pixel location to compensate for the non-uniformity.

Abstract: A method of calculating compensation data for compensating for spatial print engine non-uniformity of an image applied by a print engine to a receiver. A test target has two test areas of different output densities, each with a single output pixel level. A relationship between output density and output pixel level for the print engine is determined, and is used to calculate the output pixel level for each test area from the respective output density. The test target is printed, and the reproduced densities of the test areas are measured at a plurality of different locations in each area. A processor is used to calculate the compensation data using the measured densities. The compensation data defines a relationship between an output pixel location on the receiver, an output pixel level, and a compensated pixel level.

Abstract: A system with for capturing and storing an image of a user's handwritten alphanumeric characters. The characters are stored in memory in association with a standard alphanumeric character set such as an ASCII character set. A text document can then be transcribed into the stored handwritten alphanumeric characters for resembling a handwriting of the user. The characters can be represented by mathematical functions such as Taylor Series or McLauren Series and can be digitally reproduced based on the stored functions.