| 摘要 |
PROBLEM TO BE SOLVED: To improve graininess in a three-dimensional image to be visually recognized by unaided stereoscopic viewing.SOLUTION: A print image for stereoscopic viewing, which is visually recognized as a three-dimensional image, is printed when observed by unaided eyes through an optical member for stereoscopic viewing which has constant pitches in a lateral view direction. A dither mask to be used for halftone processing of the print image is set so that each of the following dot distributions (1) and (2) has such a noise characteristic that there is a peak on a high frequency side in a spatial frequency domain: (1) a dot distribution in M pieces of single-pixel groups, which are composed respectively as a set of pixels in individual area of M pieces of areas arrayed for every pitch of the optical member for stereoscopic viewing; and (2) a dot distribution in at least one complex pixel group, which is composed of pixels, in at least one area selected from M pieces of areas, and at least a part of pixels included in the selected area and the other areas adjacent in the lateral view direction. |
