An image forming apparatus performs a halftone process using plural dither matrices. Generated is calibration data to calculate a color registration error amount corresponding to a primary scanning directional position of an image forming available width. An image area dividing unit determines an image boundary position that is identical to any of matrix boundaries of plural dither matrices arranged in an image forming target area, and divides the image forming target area into plural image adjustment areas using the image boundary position. A correction processing unit corrects secondary scanning directional positions of the plural image adjustment areas, using respective correction amounts calculated with the calibration data. Further, the image area dividing unit determines the image boundary position using a remainder left by dividing in the primary scanning direction the number of pixels of the image adjustment area by the number of pixels of the dither matrix.

An image forming apparatus performs a halftone process using plural dither matrices. Generated is calibration data to calculate a color registration error amount corresponding to a primary scanning directional position of an image forming available width. An image area dividing unit determines an image boundary position that is identical to any of matrix boundaries of plural dither matrices arranged in an image forming target area, and divides the image forming target area into plural image adjustment areas using the image boundary position. A correction processing unit corrects secondary scanning directional positions of the plural image adjustment areas, using respective correction amounts calculated with the calibration data. Further, the image area dividing unit determines the image boundary position using a remainder left by dividing in the primary scanning direction the number of pixels of the image adjustment area by the number of pixels of the dither matrix.

A printing apparatus includes a print execution section and a controller. The print execution section includes: a printing head having nozzles arranged in a first direction; a head driver that drives the printing head to discharge ink from the nozzles thereby forming dots on a printing medium; and a movement mechanism that moves the printing medium relative to the printing head in any of the first direction and a second direction intersecting with the first direction. The controller obtains a piece of object image data, generates, by using the object image data, a plurality of pieces of dot data indicating formation states of the dots for pixels, and prints a printing image by causing the print execution section to execute discharge of the ink and movement of the printing medium by use of the pieces of dot data.

An example computer-readable medium storing machine-readable instructions that, when executed by a processor, cause the processor to receive an image, identify a first color region in the image, the first color region having a color level below a color level threshold, and fortify the first color region.

An example computer-readable medium storing machine-readable instructions that, when executed by a processor, cause the processor to receive an image, identify a first color region in the image, the first color region having a color level below a color level threshold, and fortify the first color region.

In some examples, luminance-biased sharpening for thermal media printing may include converting an input image to a grayscale luminance representation. For each pixel of a plurality of specified pixels of the converted input image, a sharpening lightness value may be determined. Further, a ratio of the sharpening lightness value to a corresponding original lightness value may be determined. A resulting sharpened pixel may be determined by applying a corresponding value of the determined ratio to each of the specified pixels. A dark correction factor may be applied to the resulting sharpened pixels that are darkened and a light correction factor may be applied to the resulting sharpened pixels that are lightened. Based on application of the dark correction factor and the light correction factor, a sharpened output image corresponding to the input image may be generated.

Provided are an image processing apparatus, a control method, and a control program to more accurately remove the shading from the image including the shading. An image processing apparatus includes a storage device to store a shading pattern in which a condition of gradation values of a target pixel and a plurality of pixels having a predetermined positional relationship with respect to the target pixel are set, an acquisition module to acquire a multiple value image, a binary image generation module to generate a binary image from the multiple value image, a detection module to detect a pixel satisfying the condition set in the shading pattern from the multiple value image as a part of a shading, a shading removal pattern generation module to generate a shading removal pattern for removing the detected shading, based on the multiple value image, a shading removal image generation module to generate a shading removal image by applying the shading removal pattern to the binary image, and an output device to output the shading removal image or information generated using the shading removal image.

An information processing apparatus includes: a processor configured to execute a first smoothing process of smoothing a black component of a color conversion table, calculate other color components of the color conversion table using the black component for which the first smoothing process is executed, and execute a first update process of updating the color conversion table based on the black component for which the first smoothing process is executed and the calculated other color components.

An information processing apparatus includes: a processor configured to execute a first smoothing process of smoothing a black component of a color conversion table, calculate other color components of the color conversion table using the black component for which the first smoothing process is executed, and execute a first update process of updating the color conversion table based on the black component for which the first smoothing process is executed and the calculated other color components.

A method for correcting in-track position errors in a digital printing system having a linear printhead includes printing a test target including a plurality of alignment marks. A data processing system is used to automatically analyze a captured image of the printed test target to determine a measured in-track position for each of the alignment marks. The measured in-track positions for the alignment marks are compared to reference positions to determine measured in-track position errors. An in-track position correction function is determined responsive to the measured in-track position errors, wherein the in-track position correction function specifies in-track position corrections to be applied as a function of cross-track position. A corrected digital image is determined by resampling an input digital image responsive to the in-track position correction function.