A look-up table for use in a printing system is created. The printing system prints an input image in a print color space. The look-up table is created by accessing a predetermined look-up table representing a mapping of color values of an input color space to ink-vectors of a print color space; applying a p-by-q halftone threshold matrix to each ink-vector of the predetermined look-up table to generate a p-by-q halftone cell for each ink-vector; and creating a further look-up table which maps, at least a sample of, the color values of input color space to the at least one halftone cell.

In some examples, a supply component for a printing device includes a memory device comprising a plurality of corrective data to produce a corresponding plurality of color tables each customized for a respective media type of a plurality of media types, wherein a respective corrective data of the plurality of corrective data corresponds to nodes of a reference color table for the printing device that is able to accept the plurality of media types for printing. The respective corrective data includes a plurality of residual values to transform the nodes of the reference color table to a customized color table for use with a selected media type of the plurality of media types.

In some examples, a print cartridge includes a memory device comprising quantized coefficients derived from a lossy compression, at a selected step size, of a difference color table including a plurality of difference nodes in which each difference node represents a difference value that is a difference of a value of a node of a color table and a value of a corresponding node of a reference table, the quantized coefficients useable to produce a reconstructed difference color table including a first set of difference nodes each representing a difference value that is within an error threshold at the selected step size, and a second set of difference nodes each representing a difference value that is outside an error threshold at the selected step size. The memory device further comprises corrective information to correct the second set of difference nodes of the reconstructed difference color table.

In some examples, a print cartridge includes a memory device comprising quantized coefficients derived from a compression of a difference table including a plurality of difference nodes in which each difference node represents a value that is a difference of a value of a node of a color table and a value of a corresponding node of a reference table, the quantized coefficients useable to produce a reconstructed difference table, and a plurality of residue nodes in which each residue node represents a value that is a difference of a value of a node of the color table and a value of a corresponding node of the reconstructed difference table.

The present invention relates to a method of generating “expanded color chart” representing various ink combination, for profiling a multi-color printing device or printer, using “reduced set of color chart”, printed using the printer, where a. The expanded color chart is computed by applying “Error Correction” function to the expanded color chart predicted using a theoretical model of color prediction for a given ink combinations in the expanded chart. b. Error Correction function is computed/modelled as function of the variance/difference observed between the color values predicted by the theoretical model and the actual values measured for the ink combinations in the printed “reduced set of color chart”.

In a color printing environment, functions for printing color management are dissociated. An abstraction layer is also provided to facilitate setting and evaluation of all factors relating to color print and prediction.

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.

A transform wrapper is stored on a memory device and the memory device may be included in a printer cartridge. The transform wrapper may dynamically build a transform map for a printer based on metadata stored at the memory device. The metadata may indicate at least one of a type of depositing material, transform map, print media and printer.

An image processing apparatus according to the present invention includes an image forming unit configured to form an image, a measuring unit configured to measure the formed image, a control unit configured to control execution of a single-color calibration to be performed to correct reproduction characteristics of a single-color formed by the image forming unit based on a measuring result of a single-color image formed with a single-color recording agent and execution of a multi-color calibration to be performed to correct reproduction characteristics of a multi-color image formed by the image forming unit based on a measuring result of a multi-color formed with a plurality of recording agents, and a selection unit configured to select whether to cause the control unit to perform the multi-color calibration after completing the single-color calibration or cause the control unit to perform any one of the single-color calibration and the multi-color calibration.

An image forming apparatus includes: a scanner to read each of a first output product serving as a model and a second output product output from the image forming apparatus; a memory that stores a color conversion lookup table to be used when color conversion is performed from a RGB color system into a CMYK color system; and circuitry to correct the color conversion lookup table based on a number of pixels and an amount of change per hue, using read information on the first output product, and re-correct the corrected color conversion lookup table, using read information on the second output product.