In an example, a method includes accessing an initial prediction of a granularity metric for a halftone pattern. A correction factor to apply to the initial prediction may be determined, the correction factor being determined from a correction factor model defining a relationship between initial predictions of granularity metrics and human perceptions of granularity. The method may further include generating, using processing circuitry, a revised prediction of the granularity metric for the halftone pattern using the correction factor.

In an example, a method comprises: receiving, at a raster image processor, image data representing a print job, the image data representing an area to be printed using a process color separation and an area to be printed using a spot color; producing at the raster image processor, a first rasterized image representing a layer of the print job having the process color and a second rasterized image representing a layer of the print job having the spot color; receiving at an emulator, the second rasterized image; and representing, by the emulator, the second rasterized image as a plurality of constituent process color separation layers.

A signal processing apparatus includes first and second processors that read and execute a program, and a memory. The first processor is configured to process plural color signals at one time and output the plural color signals in parallel. The memory is configured to temporarily store the plural color signals output from the first processor. The second processor is configured to sequentially read and process plural color signals processable at one time from the memory. The first and second processors are configured to process the plural color signals in units of bands including plural lines; after completion of processing of a first band, processing of a second band starts; and the first processor is configured to start processing the second band at a time point before completion of processing of the first band by the second processor, and at which color signals of the first band remain in the memory.

Example color resources are generated. A first luminosity amount of a greyscale color in a greyscale color space is determined. The greyscale color corresponds with a transformation of a source color in a first color space converted to the greyscale color. The source color corresponding with a depletion color in a second color space, and the depletion color has a second luminosity amount. A target color in a color resource is generated via adjusting a black channel amount in the depletion color to match the second luminosity amount with the first luminosity amount. The target color to correspond with the source color in the color resource.

Methods, systems and computer readable media for color management are described. In some implementations, the method can include accessing one or more buildup curves associated with a combination of a substrate, one or more colorants and a colorant dispenser. The method can also include accessing a design file specifying a design and including one or more layer files each specifying a layer color. The method can further include generating, for each layer color, a corresponding colorization recipe based on the one or more buildup curves. The method can also include creating a production job instruction/metadata file having a link to the design instruction/metadata file and including parameters associated with the colorant dispensing job to be carried out using the design instruction/metadata file.

In a direct stimulus value reading type colorimetric photometer, first, second, and third colorimetric optical systems have spectral responsivities approximate to first, second, and third parts of the color matching function, respectively. A deriving unit derives a colorimetric value corresponding to a case in which the color matching function is selected as an evaluation function for colorimetry and a photometric value corresponding to a case in which the spectral luminous efficiency is selected as an evaluation function for photometry (i.e. “CASE”) from three signals. The spectral luminous efficiency is not consistent with any one of the first, second, and third parts. A fourth colorimetric optical system may have spectral responsivity approximate to the spectral luminous efficiency, and the deriving unit may derive the colorimetric value corresponding to the CASE from a fourth signal.

An image processing apparatus includes a correction factor calculating unit configured to calculate a correction factor for correcting a difference in pixel values corresponding to a difference between a spectral sensitivity and a preset reference spectral sensitivity in a predetermined wavelength range at a pixel of interest, based on image data generated by an image sensor, the image sensor having a plurality of pixels on which color filters of a plurality of colors with different spectral transmittances are respectively disposed, the color filters forming a predetermined array pattern, the correction factor calculating unit being configured to calculate the correction factor for each of the plurality of pixels on which at least a predetermined color filter of the color filters is disposed.

An image forming apparatus having a plurality of imaging units prints, in a case that a print job received from an information processing apparatus is a print job for printing a chart for adjustment, the chart based on the print job, and decides, based on the chart, which of the plurality of imaging units is to be used to perform colorimetry of a printed product on which the chart has been printed. The image forming apparatus changes a conveyance path of the printed product to use the decided imaging unit for the colorimetry of the printed product, and notifies the information processing apparatus of a result of the colorimetry by the decided imaging unit.

An information processing apparatus of the present invention determines whether or not there is a bias in jobs distributed to a plurality of printers to be used in a distributed printing system. In addition, in a case where there is a bias in distributed jobs, the information processing apparatus decides a color correction target to be applied to a printer having a small number of distributed jobs and resulting in an unused state, applies the decided color correction target to the printer having a small number of jobs, to thereby decide a timing of performing color adjustment on the printer having a small number of jobs. The printer having a small number of jobs and resulting in an unused state is subjected to color adjustment at the decided timing.

The image processing apparatus (10) includes an image matching unit (14) that performs a process of matching a positional relationship between read image data which is any one of the first read image data (24) and second read image data obtained by color conversion of the first read image data (24) and original document image data (20) of the target printed matter (22); a statistical processing unit (16) that generates statistical information that reflects a distribution of read image signal values of the read image data in each image region of the read image data corresponding to an image region having the same original document image signal values in the original document image data (20); and a mismatching detection unit (18) that detects color mismatching between the original document image data (20) and the target printed matter (22) on the basis of the statistical information.