1. An image processing method of adding a white-outline to an outline of a character image with which a predetermined pattern is synthesized, comprising the steps of: generating the predetermined pattern; inputting an image signal; sharpening an edge of the character image represented by the image signal; creating data for adding a white-outline to the outline of the character image; and synthesizing the predetermined pattern with the sharpened character image in accordance with the created data so that the white-outline can be added to the outline of the character image.