| 摘要 |
In a first process, initial dot pattern of a predetermined dot rate “a” is created in a first process, and a gradation value corresponding to the dot rate “a” is arranged as a threshold value in the position of the pixel of the threshold value matrix corresponding to the initial dot pattern. Then in a second process, the initial dot pattern or the dot pattern having occurred prior to the second computation is used as the dot pattern of dot rate “b”, and new dots including the dots of the dot pattern of dot rate “b” is generated or any of the dots is removed from the dot pattern of the dot rate “b” by the error diffusion method. Thus, the dot pattern of the next dot rate “b′” with its dot rate having been increased or decreased in the aforementioned procedure is generated. |
