| 摘要 |
<P>PROBLEM TO BE SOLVED: To reduce image quality deterioration in a boundary of an area in the case of performing error diffusion processing for every area divided from an image. <P>SOLUTION: A halftone processing part 625 performs the error diffusion processing by scanning a noticed picture element so that a scanning direction of a pixel in an odd row or column and a scanning direction of a pixel in an even row or column may become reverse in a horizontal or longitudinal direction of the area for very area of the image divided into the plurality of areas. A diffusion coefficient selection part 650 sets a diffusion coefficient set for diffusing a quantization error at the time of quantizing a pixel in the vicinity of the noticed picture element over the noticed picture element in accordance with a position of the noticed picture element in a current processing area of the error diffusion processing. A error diffusion processing part 630 quantizes the noticed picture element to which the quantization error is added in accordance with the diffusion coefficient set, and stores the quantization error of the noticed picture element in a quantization error memory 640 for referring to the quantization error in the error diffusion processing of the current processing area. The error diffusion processing part 630 also stores the quantization error of the noticed picture element in accordance with the position of the noticed picture element in an error buffer 670 for referring to the quantization error in the error diffusion processing of an unprocessed area processed after processing of the current processing area. <P>COPYRIGHT: (C)2012,JPO&INPIT |
