Color error diffusion

Abstract

An error diffusion circuit and method for adoptively compensating for the distortion of brightness and color with respect to neighboring pixels. An error diffusion circuit of a color image printer having a circuit for scanning color documents and generating C-M-Y (cyan-magenta-yellow) signals from an input pixel includes a color determining portion for adding the C-M-Y signals to a diffusion error to generate a current pixel value, comparing the current pixel value with sequentially supplied error look-up data to determine an address of error look-up data having the smallest error as output pixel color information, and applying the output pixel color information to the printer; an error storage portion for storing the smallest error out of errors calculated from the color determining portion as an error for a current pixel, reading out the stored error when a next pixel is processed, and providing the read error as neighboring pixel error information to the color determining portion so as to generate the diffusion error; a neighboring pixel color information storage portion for storing the output pixel color information as neighboring pixel color information of the next pixel; and an error look-up table storage portion for storing error values generated when printing the input pixel according to the output pixel color information and providing the error values as the error look-up data to the color determining portion.