| 摘要 |
PURPOSE:To obtain reduced data having satisfactory reproducibility and high quality by intentionally diffusing the position of a representative picture element to be extracted in each picture element area based on the area position and executing thinning out. CONSTITUTION:A picture element position is designated, the picture element area to which the designated picture element belongs is judged, and it is judged whether the designated picture element is the representative picture element or not based on the area position of the decided area. Namely, the position of the representative picture element in each picture element area is not determined either to be the uniformly same position or regardless of the area position in the picture element area but determined based on the area position of the picture element area. Consequently, the periodicity of each picture element area and that of the representative picture element become different, interference can be prevented, and it can be avoided that a completely white or completely black picture is obtained when dither binarization is executed at every picture element area. Thus, the thinning out of the picture data having the satisfactory picture reproducibility and the high picture quality can be executed. |
