IMAGE PROCESSING METHOD, PRINTING SYSTEM AND PRINTER

摘要

PROBLEM TO BE SOLVED: To provide an image processing method and image processor capable of obtaining satisfactory image quality by reducing gradation characteristic distortion from an intermediate density area to a high density area. SOLUTION: This image processing method for using an error diffusion method to convert a multiple gradation input image signal into a binary output image signal comprises a density determination processing process for determining whether the input image signal whose density is smaller than predetermined prescribed density; an error diffusion processing process for using a predetermined dot generation restriction matrix to restrict a dot generation position and to binarize the dot generation position by the error diffusion method when the input image signal is determined to be smaller than the predetermined prescribed density in the density determination processing process; and a dither processing process for using the dot generation restriction matrix to determine whether to generate dots at the position of a pixel under consideration when the input image signal is determined to be larger than the predetermined prescribed density in the density determination processing process. COPYRIGHT: (C)2005,JPO&NCIPI