Patent ID: 7692804

Claim:
An image forming apparatus operable in a first image formation mode for forming an image on an image bearing member by using developer under a first predetermined image forming condition and a second image formation mode for forming an image on an image bearing member by using developer under a second image forming condition which is different from the first predetermined image forming condition, wherein said apparatus is set so that the amount of consumption of developer for forming an image in the second image formation mode is smaller than the amount of developer used for forming an identical image in the first image formation mode, said apparatus comprising: a storing device that stores setting information for setting the second image forming condition corresponding to a plurality of levels of an amount of usage of the image bearing member; a controller configured to set said image forming apparatus in the first image formation mode or the second image formation mode; and an image processing controller configured to discriminate the size of a concentrated pixel area in image information when the second image formation mode is set and to perform first and second image density lowering processes on image information presenting pixel areas of different sizes, depending on the discriminated size of the pixel area, wherein in a state in which said controller is configured to set said image forming apparatus in the second image formation mode, an image density lowering process performed on the image information by said image processing controller is changed depending on the discrimination result of said image processing controller in such a manner that the first image density lowering process is performed so that image information representing pixels in pixel areas of a first size of the image to be formed has a first image density, and the second image density lowering process is performed so that image information representing pixels in pixel areas of a second size of the image to be formed has a second image density lower than the first image density, and wherein said controller sets an image forming condition for a first size of the image and a second size of the image as the second image forming condition by using the setting information, stored in said storing device, corresponding to the amount of usage of the image bearing member.