Halftone process giving specified characteristics to particular dot patterns, and generating and evaluating a dither matrix therefor

摘要

A printing method for performing a halftone process on image data representing input tone values of pixels constituting an original image to determine dot formation on each print pixel of a print image to be formed on a print medium, generating dot data representing the determined dot formation, and forming a dot on each of the print pixels for generating the print image according to the dot data. The step of generating the print image includes mutually combining dots formed on print pixels belonging to each of a plurality of pixel groups in a common print area, the plurality of pixel groups having a physical difference at dot formation, the dot formation being performed with respect to each of the pixel groups. A plurality of pixel groups having a physical commonality for the dot formation among the plurality of pixel groups constitute a pixel group family. The halftone process is configured to give specified characteristics with a first dot pattern being formed on print pixels of the print image, a second dot pattern being formed on print pixels belonging to each of the plurality of pixel groups, and a third dot pattern being formed on print pixels belonging to the pixel group family.