Patent attributes
Provided is an image reading apparatus, including a reading portion which reads an image and generates gradation values of each pixel, a calculation portion which calculates a coefficient group that allows the gradation values of each pixel generated as the reading portion reads a reference image, to be close to the gradation values of the pixels which correspond to image data forming the reference image, divides plural regions including an overlapped part in which the reference images are overlapped with each other, and calculates the coefficient group in each region, and a correction portion which corrects the gradation values of each pixel generated as the reading portion reads a correction target image, and corrects the gradation values of the correction target which correspond to the gradation values of the pixels of the overlapped part using the coefficient group.