An information processing apparatus includes a recognition unit that recognizes an object which is included in an image and is expressed using a single color, and a conversion unit that performs conversion on a pixel, which is included in the image and corresponds to a designated color, into a specific color, and, in a case where a color of an area, which is in contact with an outer edge of the recognized object, is designated and a difference between the color of the recognized object and the specific color is smaller than a first reference, performs conversion on a pixel of the outer edge into a color other than the specific color.

Image analysis and processing may include a multiple-tone-control (MTC) unit configured to obtain a tone-control gain lookup table, a plurality of MTC gain lookup tables, wherein the input image is divided into a plurality of blocks and wherein the plurality of MTC gain lookup tables includes a respective MTC gain lookup table corresponding to each respective block from the plurality of blocks, MTC grid parameters, MTC weighting parameters, a tone-control gain based on the tone-control gain lookup table, a MTC gain based on at least one MTC gain lookup table from the plurality of MTC gain lookup tables, the MTC grid parameters, and the MTC weighting parameters, and an output value based on the tone-control gain and the MTC gain.

An image processing device includes an image reader that reads an image, a first determiner that determines whether character crushing occurs when the image is binarized, a second determiner that determines a rate of a photographic region in the image, and a controller that performs conversion into monochrome N-gradation image data based on determination results of the first and second determiners.

An image forming system according to one aspect of the present disclosure includes an image distribution device and a printing device. The image distribution device distributes print image data, which includes frame image data including an image applied commonly to a plurality of print materials and variable data including information changed on a print material basis, to an external device via a network. The frame image data is configured to enable a setting that a special color setting is required. When the setting indicating that a special color setting is required is made for the frame image data, the printing device uses a color profile associated with the setting to combine the frame image data and the variable data and form the print image.

A color chart is for performing color adjustment on an image forming apparatus. The color chart includes identification information and a color adjustment patch. The identification information is on an image forming apparatus to which color adjustment is to be applied. The color adjustment patch includes a plurality of color patches for performing color adjustment on the image forming apparatus indicated by the identification information.

An image forming apparatus includes an image forming device that forms an image on a recording medium and circuitry that controls the image forming device. The image forming device forms an invisible image with an invisible material on the recording medium and forms a visible image with a visible material on the invisible image. Each of first and second adhesion amounts includes respective adhesion amounts of the visible material and the invisible material per unit area in a portion, in which the visible image is formed on the invisible image, of the composite image. The second adhesion amount is smaller than the first adhesion amount. The controller adjusts the amount of the invisible material included in the second adhesion amount to be smaller than that included in the first adhesion amount, to cause the image forming device to form the image according to the second adhesion amount.

An image forming apparatus includes: a scanner to read each of a first output product serving as a model and a second output product output from the image forming apparatus; a memory that stores a color conversion lookup table to be used when color conversion is performed from a RGB color system into a CMYK color system; and circuitry to correct the color conversion lookup table based on a number of pixels and an amount of change per hue, using read information on the first output product, and re-correct the corrected color conversion lookup table, using read information on the second output product.

The occurrence of image quality adverse effects, such as interference fringes and color bleeding, is suppressed for an object including a spot color adjustment-target color. In a case where a spot color adjustment function is made use of, the same color separation table is caused to be applied uniformly, instead of switching color separation tables to be applied to an adjustment-target color depending on whether the object attribute is text/line/graphics, or image.

Image analysis and processing may include a multiple-tone-control (MTC) unit configured to obtain a tone-control gain lookup table, a plurality of MTC gain lookup tables, wherein the input image is divided into a plurality of blocks and wherein the plurality of MTC gain lookup tables includes a respective MTC gain lookup table corresponding to each respective block from the plurality of blocks, MTC grid parameters, MTC weighting parameters, a tone-control gain based on the tone-control gain lookup table, a MTC gain based on at least one MTC gain lookup table from the plurality of MTC gain lookup tables, the MTC grid parameters, and the MTC weighting parameters, and an output value based on the tone-control gain and the MTC gain.

The occurrence of image quality adverse effects, such as interference fringes and color bleeding, is suppressed for an object including a spot color adjustment-target color. In a case where a spot color adjustment function is made use of, the same color separation table is caused to be applied uniformly, instead of switching color separation tables to be applied to an adjustment-target color depending on whether the object attribute is text/line/graphics, or image.