Image processing apparatus and image processing method

Upon adding a visible electronic signature to an electronic file, deterioration in visibility of characters is prevented by arranging a character image data of a portion overlapping with a region of the visible electronic signature in an upper position layer above the visible electronic signature. There are included a step for extracting a character image data from an image data, a step for generating a character image layer data in which only the character image data is described on a transparent background if a region where the visible electronic signature is arranged and the region of the character image data overlap with each other, and a step for generating an electronic file with a layered structure having the character image layer data, the visible electronic signature and the image data in that order from an upper position of the layered structure.