A dynamic image processor which measures a position of a structure in a plurality of frame images obtained by dynamic imaging, the dynamic image processor including a hardware processor which calculates an evaluation value indicating similarity to the structure for each position in each of the frame images, extracts at least one position candidate of the structure from each of the frame images based on the evaluation value, extracts a plurality of position candidates from at least one of the frame images, stores a plurality of route candidates in a storage by chronologically linking the position candidate extracted from each of the frame images to be a route candidate, determines one of the route candidates as a movement route of the structure, and determines the position candidate included in the determined route as the position of the structure in each of the frame images.
