Method and device for extracting a specified image subject including an extracting condition of an extracting algorithm of a subsequent stage so as to be adapted to an extraction result by the extracting algorithm of a precedent stage, when specified image subject extracting algorithms are successively implemented. At the time of performing the specified image subject extracting algorithms in each stage by parallel processing, the method and device manage extraction states of each step and qualify extraction processing conditions in the subsequent stage in accordance with the extraction states in the precedent stages. The method and device perform a vote in an N-dimensional space of image characteristic quantity for each extraction area by the specified image subject extracting algorithm and then perform weighting of degree of certainty as the specified image subject based on an aggregation value of the vote within a section area for aggregation in the N-dimensional space.