Patent ID: 8849142

Claim:
An image forming device comprising: a fixing unit configured to fix a first image to be fixed onto a sheet, the first image to be fixed being supported on the sheet; a target fixing temperature varying unit configured to vary a target fixing temperature during a time period in which a fixing process is performed; and a gradation processing unit configured to apply a gradation process to first image information, wherein the target fixing temperature varying unit is configured to vary the target fixing temperature for the sheet to which the fixing process is applied, depending on a presence or an absence of a halftone process, and depending on a type of the gradation process to be utilized, the gradation processing unit is configured to perform plural types of gradation processes, and the gradation processing unit is able to apply a dither method as a first one of the plural types of the gradation processes, and when the type of the gradation process to be utilized is the dither method, the target fixing temperature varying unit varies the target fixing temperature, depending on a type of the dither method, and depending on a first line density.