Patent ID: 7965419

Claim:
A printing apparatus that performs printing on a print medium, comprising: a dot data generator that performs a halftone process on image data representing a tone value of each of pixels constituting an original image to determine a status of dot formation on each of print pixels of a print image to be formed on the print medium, for generating dot data representing the determined status of dot formation, and a print image generator that forms a dot on each of the print pixels for generating the print image according to the dot data, wherein the print image generator is configured to generate the print image by mutually combining dots formed on print pixels belonging to each of a plurality of pixel position groups in a common print area, the print image generator has a printing head and generates the print image by forming dots on each of the print pixels during forward scan and backward scan of the printing head, while performing a main scan of the printing head, the plurality of pixel position groups includes a first pixel position group for which dots are formed during the forward scan of the printing head and a second pixel position group for which dots are formed during the backward scan of the printing head, the dot data generator is set such that the halftone process is configured to provide each of dot patterns with a predetermined characteristic, each of the dot patterns including dot patterns formed on the print pixels belonging to each of the plurality of pixel position groups, the predetermined characteristic is either one of blue noise characteristics and green noise characteristics, and the halftone process is configured such that any first correlation coefficients are higher than any of second correlation coefficients at least for tone levels with relatively low dot density, wherein the first correlation coefficients are coefficients between each of spatial frequency distributions of the dot patterns formed on the print pixels belonging to each of the plurality of pixel position groups and spatial frequency distribution of the print image, and the second correlation coefficients are correlation coefficients between each of spatial frequency distributions of dot patterns formed on print pixels belonging to each of any of other plurality of the pixel position groups that form print images by mutually combining in a common print area and the spatial frequency distribution of the print image.