| 摘要 |
PROBLEM TO BE SOLVED: To enable even a general user who does not has the knowledge of the constitution and colors of an image to perform processes for converting a color image and a multi-valued black-and-white image into a more attractive black-and-white image with expressing power and giving effects of pen drawing. SOLUTION: A two-dimensional color image stored in a source image area 3a1 of a RAM 3 is converted into a black-and-white multi-valued image, which is stored in an image area 3a2 for processing; and the histogram of the stored black-and-white multi-valued image is generated, the peak of lightness of the stored black-and-white multivalued image is detected, and on the basis of the generated histogram and the detected peak of lightness, the lightness of the black-andwhite multi-valued image is converted by using a lightness averaging conversion table 3c and a lightness conversion table 3d. |
