Abstract: An information processing apparatus includes: circuitry that converts: a total-amount restriction value that is input into a value corresponding to a gradation value; for each of colors of color materials included in an image forming apparatus, convert a gradation value of color information into a value of a color material amount normalized using a gradation value of the color of the color information; perform total-amount restriction on the normalized and converted value of the color material amount of the each of the colors based on the converted value corresponding to the gradation value; and convert the value of the color material amount of the each of the colors after the total-amount restriction into the gradation value of the each of the colors.

Abstract: An image processing device includes: a first contamination detection circuit to detect contamination on an image reading device using a first relative threshold value calculated from a standard deviation of pixel values of a same-density region in a read image obtained by the image reading device, the image reading device reading a reference image formed on a recording medium by a line head including a plurality of inkjet heads and that has density regions of a plurality of gradations; a second contamination detection circuit to detect contamination on the image reading device using a second relative threshold value calculated from a standard deviation of pixel values of an area in the read image, the area being divided for each of the plurality of inkjet heads; and a contamination processing circuit to eliminate an influence of the contamination on the read image when at least one of the first contamination detection circuit or the second contamination detection circuit determines the contamination.

Abstract: An information processing apparatus includes: circuitry that converts: a total-amount restriction value that is input into a value corresponding to a gradation value; for each of colors of color materials included in an image forming apparatus, convert a gradation value of color information into a value of a color material amount normalized using a gradation value of the color of the color information; perform total-amount restriction on the normalized and converted value of the color material amount of the each of the colors based on the converted value corresponding to the gradation value; and convert the value of the color material amount of the each of the colors after the total-amount restriction into the gradation value of the each of the colors.