A method for processing an object for printing, the object comprising a plurality of properties defined at each of a plurality of locations within the object, each property represented by a metamer set of possible combinations of proportions of at least one of a set of printing materials, the method comprising: selecting a combination of the metamer sets of a given location within an object that provides all of the plurality of properties defined for the given location.

An example system in accordance with an aspect of the present disclosure includes a halftone engine and a gray value engine. The halftone engine is to apply halftoning to an image recursively across a plurality of levels of image scales and spatial resolutions, to generate a pattern that is at least quasi-periodic across the plurality of levels. The gray value engine is to substitute gray values recursively for at least a portion of the halftoning.

A printing method for performing printing while complementing black with composite black, the printing method including: printing a test pattern having a plurality of patch images for which composite mode varies, this test pattern being printed for each dot size of the black to be complemented; causing a user to select a desired patch image from among the plurality of the patch images included in the printed test pattern, the selection being made for each of the dot size of the black ink to be complemented; and performing printing while complementing the black to be complemented with the composite black generated on a basis of the composite mode corresponding to the desired patch image selected correspondingly to the dot size of the black ink to be complemented.

An image capturing unit captures an image including an embedded image that is printed on the basis of image data in which at least a color component has been modulated according to additional information. An adjustment unit adjusts a white balance of the image captured by the image capturing unit on the basis of an adjustment value associated with the embedded image. A processing unit processes image data of the image captured by the image capturing unit whose white balance has been adjusted by the adjustment unit to read the additional information in the image captured by the image capturing unit.

An embodiment of the present disclosure provides a method for processing an image. The method comprise: determining weights corresponding to candidate colors for a target color based on an original color of a pixel in the image; selecting a target color of the pixel from the candidate colors based on the weights; and converting the original color of the pixel into the target color to obtain a target image. According to the embodiment of the present disclosure, by determining the weights of the candidate colors, the image can be converted into the target image comprising only the candidate colors, thereby using a limited number of candidate colors to represent the target image.

An example method comprises setting a mixture of a plurality of print supplies of a print device to use for a process black print based on a plurality of supply levels corresponding to the plurality of print supplies. The example method further comprises initiating execution of the process black print of a print job by the print device using the set mixture of the plurality of print supply as overlapping colorant with the black print supply of the print device.

An image processing apparatus includes a processor configured to: store a first color patch used in using metallic toner and a second color patch used in using CMYK toner other than the metallic toner without using the metallic toner; receive a first colorimetric value obtained by measuring color of the first color patch and a second colorimetric value obtained by measuring color of the second color patch; calculate a third colorimetric value on a basis of the first colorimetric value obtained by measuring the color of the first color patch and the second colorimetric value obtained by measuring the color of the second color patch, and generate a profile to be used to convert an input color value into an output color value, the profile being generated on a basis of the third colorimetric value; and calculate the third colorimetric value that ranges from the first colorimetric value to the second colorimetric value in response to a total amount of CMYK toner being lower than or equal to a threshold, the total amount of the CMYK toner resulting from color conversion of the input color value performed by using the profile, and calculate the third colorimetric value that coincides with the first colorimetric value in response to the total amount exceeding the threshold.

An example image forming apparatus includes a print engine to form an image by using toners of different colors, a memory to store toner quantity information of the different colors of toners, and a processor to perform a print job by reducing a use of a toner with a small toner residual quantity ratio when a difference in a residual quantity ratio of the toner for each color is greater than or equal to a determined value on the basis of the stored toner quantity information.

A method is disclosed. According to some examples, the method comprises determining, by processing circuitry, a first element set to be associated with a print addressable location, the first element set comprising a first plurality of elements, wherein each element of the first plurality of elements identifies a print colorant or print colorant combination and is associated with a probability that the print colorant or print colorant combination identified by that element is to be applied to the associated print addressable location. The method may comprise determining, by processing circuitry, a second element set to be associated with the print addressable location, the second element set comprising a second plurality of elements, wherein each element of the second plurality of elements identifies a print agent or print agent combination and is associated with a probability that the print agent or print agent combination identified by that element is to be applied to the associated print addressable location. The method may comprise determining, by processing circuitry, a combined element set based on the first element set and the second element set. An apparatus and a machine-readable medium are also disclosed.

In a document represented by CMYK process colors, a color that a user wishes to remove is prevented from remaining without being removed by specified color removal, and even a color that the user does not wish to remove by rights is prevented from being removed.