Patent attributes
An image processing apparatus, comprising: an exposing device for exposing an image forming material so as to form a latent image on the image forming material based on image data; a developing device for developing and visualizing the latent image on the exposed image forming material so as to form an image; a measuring device for measuring the image density of the image on the developed image forming material; a calibrating device for forming a table to define a relation between an image signal and image density on the basis of plural different test image data and measured-image densities thereof; a storing device for storing a characteristic change model indicating a characteristic change of at least one of the exposing device and the developing device with time; a difference calculating device to calculate a density difference on the basis of the characteristic change model between the time of forming the table and the time of forming an image based on image signal of diagnostic image data; and a correcting device for correcting the table on the basis of the density difference calculated by the difference calculating device.