Patent attributes
An image reading apparatus determines an inclination amount corresponding to an inclination angle of a leading edge of an original document in a conveyance direction, and determines the length of the original document in the conveyance direction. The image reading apparatus sets a first value as a set value in a case that the length of the original document is a first length and sets a second value larger than the first value as the set value in a case that the length of the original document is a second length shorter than the first length. If the inclination amount is smaller than the set value, inclination correction for correcting the image represented by the image data is performed such that the inclination amount is reduced, and if the inclination amount is larger than the set value, the inclination correction is not performed.