A method for reproducing an out-of-gamut spot color includes determining a color gamut for a color printer, and specifying a spot color by color coordinates in a three-dimensional color space. A first target color is determined corresponding to a color having a minimum color difference to the specified spot color, and a second target color is determined corresponding to a color on the color gamut surface having a hue value equal to a hue value of the specified spot color. A path is defined on the color gamut surface connecting the first target color and the second target color, wherein a control parameter is used to specify a relative position along the defined path. A control parameter prediction function is provided which computes a predicted control parameter value as a function of color coordinates. The predicted control parameter value is used to determine an aim color for reproducing the spot color.

A method for reproducing an out-of-gamut spot color includes determining a color gamut for a color printer, and specifying a spot color by color coordinates in a three-dimensional color space. A first target color is determined corresponding to a color having a minimum color difference to the specified spot color, and a second target color is determined corresponding to a color on the color gamut surface having a hue value equal to a hue value of the specified spot color. A path is defined on the color gamut surface connecting the first target color and the second target color, wherein a control parameter is used to specify a relative position along the defined path. A control parameter prediction function is provided which computes a predicted control parameter value as a function of color coordinates. The predicted control parameter value is used to determine an aim color for reproducing the spot color.

An apparatus for processing an image, includes circuitry configured to: input a first image indicating a target color; input a second image formed by an image forming device to be subjected to adjustment; determine types of objects; and compare the first image and the second image and generate, for each of the types of the objects, a color conversion parameter, based on a correspondence between a chromaticity value in the first image and a chromaticity value in the second image.

An apparatus for processing an image, includes circuitry configured to: input a first image indicating a target color; input a second image formed by an image forming device to be subjected to adjustment; determine types of objects; and compare the first image and the second image and generate, for each of the types of the objects, a color conversion parameter, based on a correspondence between a chromaticity value in the first image and a chromaticity value in the second image.

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.

An apparatus includes a specifying unit that specifies a color; an input unit that inputs an image; a converting unit that converts a color in the image, which has a hue within a predetermined range with respect to the specified color, into a color of a predetermined hue and converts a color in the image, which has a hue outside the predetermined range with respect to the color, into black; a printing unit that prints the image subjected to the converted color; and a counting unit that separately counts a number of sheets when the printed image includes the color of the predetermined hue and a number of sheets when the printed image does not include the color of the predetermined hue.

An apparatus includes a specifying unit that specifies a color; an input unit that inputs an image; a converting unit that converts a color in the image, which has a hue within a predetermined range with respect to the specified color, into a color of a predetermined hue and converts a color in the image, which has a hue outside the predetermined range with respect to the color, into black; a printing unit that prints the image subjected to the converted color; and a counting unit that separately counts a number of sheets when the printed image includes the color of the predetermined hue and a number of sheets when the printed image does not include the color of the predetermined hue.

An optical writing device, and a method of controlling the optical writing device. The optical writing device and the method includes controlling speed of operation of a light deflector based on image magnifying-power information in a sub-scanning direction parallel to a direction in which a surface of a photoconductor moves, and controlling a prescribed write clock frequency such that a number of clock pulses of write light will become a target number of pulses over a period where the write light scans an area within a prescribed distance in a main scanning direction, the target number of pulses being maintained even when the speed of operation of the light deflector is changed in the controlling the speed of operation of the light deflector. The write clock frequency controller maintains the target number of pulses even when the speed of operation of the light deflector is changed by the light-deflector controller.

A multilayer identification document including a first layer including a color component of a color image and a second layer including a grayscale component of the color image, wherein the grayscale component is laser-engraved on the second layer. The color component is printed on the first layer and defines a multiplicity of voids in a preselected arrangement. The color component and grayscale component are at least partially superimposed to yield a hybrid color image.