A representative pixel value calculation unit (120) divides an image represented by raw data (D0) into a plurality of blocks and calculates representative pixel values (S) for each block. A detection unit (130) detects an object block which is a block including a blown-out highlight or a blocked-up shadow, from among the plurality of blocks. A B-detection unit (134) of the detection unit (130) performs a first detection processing for obtaining one of a difference between a color represented by the representative pixel values and gray, and a value that can approximately represent the difference, as a characteristic value, and for detecting, as the object block, a block in which the characteristic value is equal to or smaller than a first threshold. Consequently, blown-out highlights or blocked-up shadows included in an image can be detected at higher speed, and the omission of detection can be prevented.