Patent ID: 7515318

Claim:
An image processing method for performing a predetermined conversion process with respect to input image data corresponding to each of pixels constituting an image to be formed on a recording medium by plural species of dots which can display an identical hue and are different in at least one of a density and a diameter, said method comprising: a first generation step for generating independent multi-level data corresponding to the respective plural species of dots on the basis of input image data corresponding to a target pixel; and a second generation step for generating data relating to an amount of generation of the plural species of dots with respect to the target pixel on the basis of a relationship between the independent multi-level data, corresponding to the respective plural species of dots, generated in said first generation step, wherein said first generation step includes: (A) a conversion step of converting input image data into independent data corresponding to the plural species of dots, (B) an addition step of adding an error obtained through a predetermined manner to the converted data, and (C) a step of generating independent multi-level data corresponding to the plural species of dots by quantizing the data obtained in said addition step, and wherein the error is calculated on the basis of the data obtained in said addition step and the data obtained in said second generation step.