1. An image processing method comprising: an inputting step of inputting an image signal of a region read by an image reader; a region-selecting step of selecting a part of the read region; a detecting step of detecting a background-color region in accordance with the image signal of the read region input by the inputting step and an image signal of the selected region selected by the region-selecting step; and a background-color-removing step of removing a background color contained in the selected region in accordance with the level of an image signal of the background-color region detected by the detecting step.