It is guaranteed that a designated color that is a target of spot color matching is converted correctly into a destination color thereof at the time of output. In a case where drawing data for causing an image output apparatus to perform drawing of an image is generated, whether a designated color in a first color space, which is included in an input image, is converted into a destination color in a second color space, which can be handled by the image output apparatus, is determined at the time of output of the image. Then, in a case where it is determined that the conversion is performed, control is performed such that color adjustment is not performed for at least the designated color of colors included the input image.

In an example implementation, a method of providing image registration information in a digital printing press includes imaging a printed page on an impression drum of a digital printing press, determining image registration information from printed content on the page, and displaying a graphical visualization of the image registration information on a user interface screen of the digital printing press.

With this invention, color shifting correction is performed first based on shifting amount information indicating a shifting amount with respect to the scanning direction on an image carrier of each image forming unit, and halftone processing is then performed, thus suppressing generation of moiré due to the color shifting correction, and forming a high-quality image. To this end, an image forming engine has color shifting amount storage units C, M, Y, and K (black) which store actual shifting amounts with respect to ideal scan directions on image carriers C, M, Y, and K in image forming units C, M, Y, and K. Color shifting correction amount arithmetic units C, M, Y, and K calculate color shifting correction amounts for respective color components on the basis of the stored color shifting amounts. Color shifting correction units C, M, Y, and K perform color shifting correction by converting coordinates upon reading out image data from bitmap memories C, M, Y, and K on the basis of the calculated color shifting correction amounts, and then perform tone correction. Data after tone correction undergo halftone processing by halftone processors. C, M, Y, and K. PWM processors C, M, Y, and K generate PWM signals for scanning, and output them to exposure units C, M, Y, and K of the respective image forming units.

An image forming system includes: a reading unit configured to read a test image, the test image having a determination image formed by overlapping a plurality of colors and a plurality of reference images formed with each of a plurality of reference colors; and a determination unit configured to determine a first color value of each of the plurality of reference colors based on a reading result of the reference images, determine a second color value of a plurality of pixels included in the determination image based on a reading result of the determination image, and determine whether an image defect has occurred based on an angle of a second vector corresponding to the second color value of the plurality of pixels with respect to a first vector corresponding to the first color value of each of the plurality of reference colors.

An image forming system includes: a reading unit configured to read a test image, the test image having a determination image formed by overlapping a plurality of colors and a plurality of reference images formed with each of a plurality of reference colors; and a determination unit configured to determine a first color value of each of the plurality of reference colors based on a reading result of the reference images, determine a second color value of a plurality of pixels included in the determination image based on a reading result of the determination image, and determine whether an image defect has occurred based on an angle of a second vector corresponding to the second color value of the plurality of pixels with respect to a first vector corresponding to the first color value of each of the plurality of reference colors.

Examples of an apparatus and method for use with a printing system are described herein. A correction to be applied to a printing system during print calibration is obtained. A distortion is applied to the correction. A relationship between an expected and measured output of the printing system is determined based on the print performed at least in part on the distorted correction. The printing system is calibrated on the basis of the determined correction.

An information processing apparatus includes: a processor configured to execute a first smoothing process of smoothing a black component of a color conversion table, calculate other color components of the color conversion table using the black component for which the first smoothing process is executed, and execute a first update process of updating the color conversion table based on the black component for which the first smoothing process is executed and the calculated other color components.

An information processing apparatus includes: a processor configured to execute a first smoothing process of smoothing a black component of a color conversion table, calculate other color components of the color conversion table using the black component for which the first smoothing process is executed, and execute a first update process of updating the color conversion table based on the black component for which the first smoothing process is executed and the calculated other color components.

A printing apparatus includes a printing unit, a colorimetry unit, a data generation unit configured to generate color chart data, and a printing colorimetry control unit configured to control printing performed by the printing unit and colorimetry performed by the colorimetry unit, where the data generation unit acquires, from a first image represented by a first print job, a position of a first spot color contained in the first image and generates the color chart data having the first spot color patch disposed at a position corresponding to a position of the first spot color in the first image, and the printing colorimetry control unit causes the printing unit to print the color chart that is based on the color chart data and causes the colorimetry unit to measure the color of the color chart printed on the printing medium by the printing unit.

A printing apparatus includes a printing unit, a colorimetry unit, a data generation unit configured to generate color chart data, and a printing colorimetry control unit configured to control printing performed by the printing unit and colorimetry performed by the colorimetry unit, where the data generation unit acquires, from a first image represented by a first print job, a position of a first spot color contained in the first image and generates the color chart data having the first spot color patch disposed at a position corresponding to a position of the first spot color in the first image, and the printing colorimetry control unit causes the printing unit to print the color chart that is based on the color chart data and causes the colorimetry unit to measure the color of the color chart printed on the printing medium by the printing unit.