Patent ID: 8643910

Claim:
An image forming apparatus comprising: an acquiring unit that acquires image data expressing an image region included in an image with a first value and a background region included in the image with a second value; a segmenting unit that segments the image region expressed with the first value in the acquired image data into a plurality of segments arranged in a fast scanning direction; a converting unit that converts a value of at least one of the plurality of segments arranged in the fast scanning direction into the second value; an output unit that generates an image signal on the basis of the image data, in which the value of the at least one segment is converted, and outputs the image signal; an exposure unit that exposes a charged image bearing member to light according to the output image signal by scanning the light thereto in the fast scanning direction so as to form a latent image; and a developing unit that forms the image by developing the formed latent image using an invisible toner that absorbs infrared light or ultraviolet light; a memory that stores a plurality of image patterns each having the plurality of segments, each image pattern expressing at least one of the plurality of segments arranged in the fast scanning direction with the second value and expressing the remaining segment or segments with the first value; a transfer unit that transfers the image formed by the developing unit to a transfer medium; a first measuring unit that measures an amount of the invisible toner that forms the image transferred to the transfer medium by the transfer unit; and a selecting unit that selects an image pattern having a larger number of segments expressed with the first value than the image region, in which the value of the at least one segment is converted by the converting unit, from the plurality of image patterns stored in the memory if the amount of the invisible toner measured by the first measuring unit is smaller than a first threshold value, wherein the converting unit converts values of the plurality of segments in accordance with the image pattern selected by the selecting unit.