Patent ID: 8238772

Claim:
An image forming apparatus which forms a color image by using a plurality of color toners in accordance with an electrophotographic process, the apparatus comprising: a toner consumption amount detection unit that detects a toner consumption amount of each of the plurality of color toners; a decision unit that decides upon a color for forming a patch by comparing the detected toner consumption amount of each of the plurality of color toners to a threshold which is changed in accordance with input image data; a forming unit that forms the patch, by using a toner of the decided color, outside of an area to form a color image in accordance with the input image data; a patch density detection unit that detects a density of the formed patch; and an adjustment unit that adjusts a printing density based on the detected density of the formed patch, wherein the decision unit decides upon the color for forming the patch by choosing the color that has a larger detected toner consumption amount in comparison to other colors.