| 摘要 |
<P>PROBLEM TO BE SOLVED: To suppress deterioration of reproducibility due to binarization of a fine line or a character of a low gradation-level. <P>SOLUTION: A dither matrix 221 is formed by arranging four sub matrices of 4×4 pixels, and a threshold value of the sub matrix is set so that dot for two or more pixels is not disposed in any column in a lateral direction, a longitudinal direction and a diagonal direction in the sub matrix when the four-pixels dot is turned on in the sub matrix. That is, in the dither matrix 221, at the time of a growth step of the dot due to the increase in an input value (a pixel value of an image as a target of binarization), the one-pixel dot is disposed in the all columns in the lateral direction and the longitudinal direction at the earliest stage, and further, the dot is distributed without unevenly disposing two or more pixels dot in any column in the diagonal direction at the stage. <P>COPYRIGHT: (C)2012,JPO&INPIT |
