Patent ID: 7878613

Claim:
A method of generating print data for printing by a plurality of times of scanning of a print head arranging a plurality of nozzles to a given region on a print medium, said method comprising the step of: generating print data for printing in each of the plurality of times of scanning, by thinning print data for printing on the given region with use of a plurality of mask patterns corresponding to the plurality of times of scanning, respectively, wherein each of the plurality of mask patterns corresponding to the plurality of times of scanning arranges print permitting areas that permit printing based on the print data and print non-permitting areas that do not permit printing based on the print data in a scanning direction, in correspondence with each of the plurality of nozzles, and the print permitting areas are not adjacent to each other in the scanning direction, wherein a ratio of the print permitting areas in the mask pattern corresponding to end nozzles of the printing head is smaller than a ratio of the print permitting areas in the mask pattern corresponding to central nozzles of the printing head, and wherein each of the plurality of mask patterns arranges the print permitting areas aperiodically in the scanning direction.