PURPOSE: To enable a user to directly designate his intended color with one operation without wavering with respect to the picture processing system like a CAD system or a multimedia system which has the function to plot a line, a surface, or the like.

CONSTITUTION: A color data conversion part 205 converts a video signal 205a, which is obtained by picking up the image of an arbitrary object by an object image pickup part 206, to an RGB data 207a. A color averaging processing part 207 averages RGB data 207a to generate monochromatic RGB data 209c. A shape data color editing part 209 colors shape data 209a, which is taken out from a shape data storage part 202, with RGB data 209c, and a shape data display part 210 displays picture data 211a, which is obtained by processing for display output of this data 209a, to a graphic input/output device 211. Thus, the user can directly designate his intended color with one operation without wavering.