1. An image processing method comprising: using a processor to: detect a plurality of data regions from input image data in a first step, rotate said input image data in accordance with inclination of an image within said input image data in a second step, detect whether said rotated data region protrudes from said input image data previous to rotation in a third step, and extract an area of a size identical to a size of said input image data and having a best relative position with respect to said data regions in a fourth step, when protrusion is detected at said third step.