An image processing apparatus includes circuitry configured to receive a designation of a to-be-corrected color that is a process color or a special color different from the process color and is to be corrected; identify, on the basis of the designation, a tone correction pattern, and generate rendering data of the tone correction pattern to be used for forming an image on a recording medium; obtain a standard value of the to-be-corrected color; and correct the to-be-corrected color on the basis of a difference between a color measuring result obtained from measuring a color of the image, of the tone correction pattern formed on the recording medium and the standard value.

A color printing system includes a color management server and one or more printing devices. The color management server manages color printing resources among the printing devices. A test chart is printed at a printing device and used to capture calibration measurement data. Calibration settings are defined for the calibration measurement data. A tone reproduction curve (TRC) is generated based on the calibration measurement data and the calibration settings. The TRC is stored with the TRC settings and calibration measurement data to be used at a printing device. ICC profiles are shared between printing devices following a match calibration operation between the printing devices. An ICC profile is transferred from one printing device to another. If the ICC profile is updated, then the updated ICC profile is transferred to the matched printing device.

A color adjustment system includes circuitry to register job data for requesting printing a document file in a memory, register color sample data associated with the job data in the memory, cause a printing apparatus to print out the document file corresponding to the job data as a first printed matter, cause a reading apparatus to read the first printed matter to acquire first read image data, and generate an input profile based on the first read image data and the color sample data.

A control apparatus includes a controller. The controller obtains a job which is executed by a print apparatus and which is corresponded to document image data. The controller obtains read image data of a color sample corresponding to the document image data from a scanner. The controller determines whether correction of the scanner and/or the print apparatus is necessary based on the read image data. The controller corrects the scanner and/or the print apparatus based on a result of determination. The controller generates a color conversion parameter regarding a color conversion of the document image data based on a profile corresponding to the scanner and/or the print apparatus after correction, the document image data, and the read image data.

An information processing apparatus includes processing circuitry. The processing circuitry detects an abnormality in an image reading apparatus from a first spectral reflectance and a second spectral reflectance, the first spectral reflectance being generated based on data read from a reference white plate installed in the image reading apparatus, the second spectral reflectance being generated before generation of the first spectral reflectance, and identifies a cause of an abnormality in the image reading apparatus in a case where the processing circuitry detects the abnormality.

For determining a match factor regarding color match of a printed product with target values for colors, measuring fields of a printout are spectrally measured and actual measured values of the printout recorded. The target values are compared with actual measured values by determining for the printed product a color value axis from a unique color value as a start point to a second unique color value as end point and interpolation points between the first and second unique color values; determining target values for start and end points and interpolation points; determining actual measured values for start and end points and interpolation points of the printout from the actual measured values; determining a distance value representing the distance between target value and actual measured value for each start point, end point, and interpolation point; and calculating and outputting the match factor as statistical average of the distance values.

Color values are measured for a set of color targets printed by a reference printing device on a medium of a reference media type. A different printing device prints a subset of the set of color targets on another medium of this reference media type. The color values of the subset of color targets printed by the different printing device are measured, and the different device calibrated based on the measured color values for both the set that the reference printing device printed and the subset that the different device printed. The different printing device can then also be calibrated for a different media type, based on a transformation of the set of color targets printed by the reference printing device on a medium of the different media type relative to the set of color targets printed by the reference device on the medium of the reference media type.

A method is described in which sets of corresponding colorimetric values are obtained. In a set, a colorimetric value is associated with a device color. A number of device colors are selected according to the color differences between colorimetric values associated with the same device color. A color calibration pattern is elaborated for a printer to be calibrated using the selected device colors and calibration is performed using the sets of colorimetric values.

A method includes obtaining first color information for each of a plurality of first samples of a first target color with a color measurement device connected to a computing device including a display. A digital color image of at least one first target color is displayed on the display. An offset value for each first target color is determined such that the digital color image of each first target color matches the corresponding first target color on each of the first samples. A second sample including a second target color is scanned to obtain second color information. A processor of the computing device determines, using the offset values of the first target colors, an interpolated offset for the display such that the digital image of the second target color matches the second target color.

An object of the present disclosure is to implement, at a low cost, highly accurate color calibration in a printing apparatus that performs printing using fluorescent ink. One embodiment of the present invention is an image processing apparatus that includes: a processing unit configured to perform processing relating to color calibration in a printing apparatus that prints an image on a printing medium using fluorescent printing material; and an execution unit configured to perform calibration processing of the printing apparatus based on a measured value that is obtained by measuring a patch chart for obtaining information on an amount of application of the fluorescent printing material in the printing apparatus, wherein a patch included in the patch chart is printed with the fluorescent printing material and subtractive color mixture printing material and at least one dot of the subtractive color mixture printing material covers a dot of the fluorescent printing material.