| 摘要 |
<P>PROBLEM TO BE SOLVED: To acquire angle data which correctly reflects direction of a color change for an edge point appearing on a color image. <P>SOLUTION: Color difference Cx, Cy is calculated for each direction of X and Y for an interest pixel using image data in a mask centered around the pixel with taking each pixel constituting the color image sequentially into consideration. Furthermore, for the pixel of which summation of the color differences is a predetermined value or more, the color difference is determined for each of two directions E1, E2 passing through the pixel and corresponding to a first quadrant and a second quadrant of the XY coordinate system, and it is determined that the color change is generated in the direction with a large color difference. An angle (edge code) indicating the direction causing the color change is calculated based on the determination result and the color difference Cx, Cy. <P>COPYRIGHT: (C)2007,JPO&INPIT |
