PROBLEM TO BE SOLVED: To provide a technology capable of extracting an area capturing an object portion with high accuracy from a medical biological image capturing the motion of a structure in a body.SOLUTION: An image processor including an extraction part, a detection part and a correction part is adopted. Here, the extraction part respectively extracts capture positions at which a specific part set in advance of an object portion is captured from a plurality of frame images constituting a medical dynamic image capturing the object portion in a body. The detection part detects mismatched capture positions at which spatial relation related to the plurality of capture positions is not matched with the trend of the movement of the specific part among the plurality of capture positions extracted by the extraction part. The correction part corrects the mismatched capture positions detected by the detection part.
