Patent ID: 7898687

Claim:
A printer including a print head having nozzles that are arranged in a plurality of lines and that form dots by discharging ink onto a medium used for printing, wherein the printer prints out an image on the medium by one scanning operation using the print head, the printer comprising: a printing image data acquisition device that acquires printing image data that include image information of the image and information regarding a print position of the image; an N-level processing device that converts the printing image data that include image information having the number of addressable luminance levels M (M is natural number and M≧2) into printing image data that include image information having the number of addressable luminance levels N (N is natural number, and M≧N≧2); a dot forming information generating device that generates, on the basis of the printing image data, dot forming information that is information indicating a state of dots, formed by nozzles that constitute the print head, with respect to the printing image data; a print position information modification device that modifies, on the basis of the dot forming information, print position information that is information regarding the print position in the printing image data so that all or substantially all the nozzles that constitute the print head form a predetermined number of dots or more at every predetermined print timing during a period when printing is continuously performed; and a printing device that prints out an image on the medium using the print head on the basis of the printing image data having the number of addressable luminance levels N.