IMAGE READING APPARATUS, IMAGE READING METHOD, AND IMAGE READING PROGRAM

摘要

Provided is a technique for enabling lossless image data to be acquired even when a document is not in a rectangular shape. An image reading apparatus having a reading unit that reads an image of a document comprises: a skew angle calculation unit that calculates, on the basis of image data of the image read by the reading unit, a skew angle to be used for correcting the inclination of the document; a circumscription area detection unit that generates a first skew-corrected image obtained by rotating the image on the basis of the skew angle and scans the first skew-corrected image generated, thereby detecting a circumscribing quadrangle included in the first skew-corrected image and circumscribing the image of the document; and an image cutting-out unit that cuts out, on the basis of the coordinates of the four corner points of the circumscribing quadrangle, a cut-out document image from the image read by the reading unit.