Patent ID: 6462838
Filing Date: 2002-10-08
Classification: G06K,H04N

Abstract:
An apparatus for forming an image comprising:an error diffusion circuit adapted to apply an error diffusion method to input image data having N gradations so as to convert it into image data having M gradations and output the same, wherein said error diffusion circuit includes a converter for comparing said image data having N gradations with at least one threshold value which can be varied and converting said image data into image data having M gradations; a printing device adapted to receive said image data having M gradations outputted from said error diffusion circuit and print an image on the basis thereof; and a controller for setting parameters to be used for data processing to be carried out in said error diffusion circuit, said parameters being set in accordance with an image density of at least one test pattern printed in said printing device; wherein said threshold value is set by said controller in accordance with the image density of said test pattern.