METHOD AND DEVICE FOR GENERATING VISUAL CODE USING MULTI-LEVEL IMAGE

摘要

PROBLEM TO BE SOLVED: To generate a code by using natural images. SOLUTION: Sheets 1 and 2 as code images and a target as an objective image are multi-level images. These respective images are inputted by an image input part 10. A pixel control part 20 adjusts the contrast of the sheets 1 and 2 so as to maximize the rate (restriction satisfying rate) meeting prescribed conditions required in advance. Then, arrangement of transparent sub-pixels is controlled by each pixel to match the transparency of it with that of the pixel of the corresponding target. When the transparency cannot be matched, an approximation is adopted to distribute errors caused by it to the surroundings.