A digital camera includes an object detecting unit which analyzes an analysis target image including a through image data taken in from an image pickup device to compose a shot of an object, a shot image, or a reduced image, based on a feature appearing in an image representing a subject of shooting, and detects at least one main object captured in the analysis target image, a subject information extracting unit which extracts, for each image of object detected by the object detecting unit, subject information including a position in a screen corresponding to the analysis target image and its expansion, and a tag data writing unit which writes the subject information, as a part of tag data corresponding to the shot image, to a storage medium, thereby enabling use of the information acquired by object detection at the time of shooting, also after the acquisition of the image.