Patent ID: 7598971

Claim:
A color image forming apparatus comprising: a plurality of image forming parts each of which forms an image; a transfer part which transfers in order images of a plurality of colors formed by the plurality of image forming parts; a first conversion part which offsets a coordinate value of the image in a sub-scanning direction to convert the coordinate value of the image, based on misregistration information to correct a mechanically caused misregistration of the image, for executing a misregistration correction in a unit of a pixel; a second conversion part which adjusts a gradation level of pixels in a sub-scanning direction to convert a gradation level of the image, based on the misregistration information, for executing a misregistration correction in a unit less than a pixel; and a judgment part which judges whether to execute the misregistration correction in the unit less than a pixel by the second conversion part on an object pixel, based on pixels around the object pixel.