1. An image processing method for detecting a direction of an image including a character area, inputted into a computer, said method comprising: a binary image generation step of generating a binary image of said image; a tile image generation step of generating a tile image by applying a predetermined value to tiles, each corresponding to a predetermined size area in said binary image; a character area extraction step of extracting an area in said binary image, corresponding to an area in a circumscribed rectangle surrounding connected pixels having the same value in said tile image, as a character area; and a direction detection step of recognizing a direction of characters included in said character area and thereby detecting the direction of said image.