SCREENING METHOD, SCREENING APPARATUS AND PRINTED MATTER

摘要

PROBLEM TO BE SOLVED: To provide a screening method by which generation of moire can be suppressed more than that of the conventional method even when color print is made. SOLUTION: An image means 3 receives image data of an original being a print object. A screen image generating means 2 generates a screen image comprising only high frequency components with a prescribed frequency or more and an image with multi-value gradation resulting from planarizing the gradation histogram of pixels. A screen image generating means 4 compares the gradation of the screen image with the gradation of a pixel at a position corresponding to the original image, writes a prescribed value decided to set ink for print to pixels at corresponding positions on the screening image when the gradation of pixels on the original image is the gradation of pixels on the screening image or more, and when not, writes a prescribed value decided not to set ink for print to pixels at corresponding position on the screening image to generate the screening image.