In an image recording apparatus, when an image is recorded on a recording medium, the recording medium passes through a head part only once. Before the image is recorded, a value of a color component of at least some of pixels included in the image is corrected in order to reduce color mixing unevenness. At that time, on the basis of respective values of two reference color components among a plurality of color components of a correction target pixel, a value of one target color component included among the two reference color components is corrected. Alternatively, on the basis of respective values of three reference color components among the plurality of color components, a value of one target color component or respective values of two target color components included among the three reference color components are corrected.

A method for closed-loop color control in printing machines using a computer includes initially coating a printing substrate with opaque white to set up closed-loop color control in the course of a print job, subsequently applying process colors and, in the process, color measurement strips onto the opaque white, recording the opaque white and the color measurement strips using a measuring device, and, based on data recorded by the measuring device, performing closed-loop color control for process colors and opaque white using the computer. The measuring device is an inline measuring device and is initially calibrated at a fixed position of the printing substrate, then the application of opaque white is adjusted and, when a deviation stays below a maximum deviation, closed-loop control of both the opaque white and the process colors is done using the computer by taking measurements in the color control strip.

Certain examples relate to the processing of spot colors within a printing pipeline. In these example, a palette of spot colors indicated in a print job is determined. The palette is mapped to a set of vectors in a colorant-dependent color space based on a comparison of target spectral characteristics for the spot colors and measured spectral characteristics of the printing system. The set of vectors is used to assign vectors to print-resolution areas of the print job before halftoning.

First, a color close to a prediction target color is selected as a similar color from among a plurality of sample colors for which spectral reflectances of a plurality of patches are obtained. Next, for a similar color, a relational equation representing the relationship between the spectral reflectances of a solid patch (a patch with the highest ink density) and the spectral reflectances of a color prediction target patch is obtained. Finally, the spectral reflectances of the solid patch for the prediction target color are applied to the relational equation, by which predicted values of spectral reflectances of the color prediction target patch for the prediction target color are obtained.

A learning device includes an acquiring unit and a learning unit. The acquiring unit acquires an image and correction information designated for printing the image. The learning unit performs machine learning on recommended correction information that indicates correction content recommended for the print target image in printing the print target image, based on the data set in which the image is associated with the correction information.

There are provided a printing system, a method of generating a halftone processing rule, a method of acquiring a characteristic parameter, image processing device and method, a halftone processing rule, a halftone image, a method of manufacturing a printed material, an ink jet printing system, and a program which are capable of reducing an operation load of a user and acquiring a halftone processing rule appropriate for the printing system. A characteristic parameter acquisition chart including a pattern for acquiring characteristic parameters related to characteristics of the printing system is output, and the output characteristic parameter acquisition chart is read by image reading means. The characteristic parameters are acquired by analyzing the read image of the characteristic parameter acquisition chart, and halftone processing rules that define the processing contents of halftone processes used in the printing system are generated based on the acquired characteristic parameters.

An image processing apparatus includes a control unit configured to control execution of monochromatic calibration and multi-color calibration, and a registration unit configured to register paper types of paper to be used at time of execution of the monochromatic calibration, a monochromatic target value set for each of the paper types used for the monochromatic calibration, paper types of paper to be used at time of execution of multi-color calibration, and a multi-color target value set for each of the paper types used for the multi-color calibration. The image processing apparatus executes the multi-color calibration, after executing the monochromatic calibration, via the control unit by using paper of a paper type selected from common paper types out of the registered paper types and the monochromatic target value and the multi-color target value set for the selected paper type.

An image processing control apparatus includes a hardware processor. The hardware processor obtains: read image data obtained through reading a color sample and shown in a first color system; original image data corresponding to the color sample and shown in a second color system; and region-by-attribute information indicating a first region corresponding to spot-color printing and a second region corresponding to decoration printing, the first and second regions being in the original image data. The hardware processor determines a color conversion parameter for color conversion of the first region and a color conversion parameter for color conversion of a third region different from the first and second regions in the original image data by using the read image data. The hardware processor determines a color conversion parameter for color conversion of the second region according to predetermined values shown in the second color system.

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”.

An image processing apparatus includes a processor configured to generate a second color chart from a first color chart. The second color chart includes multiple color samples selected from multiple color samples included in the first color chart, and the second color chart is generated in such a manner that a color sample included in the second color chart is located in the second color chart at a position at least maintaining a partial-adjacency relationship in the first color chart.