Image processing apparatus, printing apparatus, and image processing method

摘要

Nozzles in a print head are arrayed in a density of 600 dpi. Moreover, a dither matrix has a size of 16 pixels×16 pixels in 600 dpi. The dither matrix is repeatedly used. In the meantime, each of rectangles represents an HS processing unit. WHS=3 pixels. As a consequence, the relationship of a least common multiple below is established in a nozzle array direction: 3×WD=16×WHS. In this case, the cycle of interference unevenness can be prolonged to the least common multiple between WD and WHS, that is, 48 pixels (3WD). In this manner, the size of the dither matrix is not an integral multiple of the HS processing unit width, so that the cycle of interference unevenness can be prolonged more than the size of the dither matrix. Thus, the interference unevenness can be hardly recognized.

主权项

1. An image processing apparatus that generates print data used for performing printing of an image on a printing medium by using a printing element array in which a plurality of printing elements are arrayed, said apparatus comprising:
a correction unit configured to, for each of processing units corresponding to a plurality of printing element groups, respectively, which are obtained by dividing the plurality of printing elements in the printing element array, correct image data of an image which corresponds to the printing elements in the printing element group, according to print characteristics of the printing elements in the printing element group; and a quantizing unit configured to quantize the image data corrected by said correction unit by using a dither matrix representing a plurality of thresholds that are respectively associated with data of pixels forming an image to be printed on an area having a predetermined size in an array direction of the plurality of printing elements in the print medium, wherein a plurality of areas are successively arranged in the array direction, and the dither matrix is used for each area having the predetermined size, wherein a number of pixels in the area having the predetermined size in the array direction is larger than and not multiple of a number of pixels in the array direction corresponding to the plurality of printing elements in the printing element group.