1. An image processing apparatus comprising: face-image detecting means for detecting a region of a face image from an image supplied thereto; face-direction detecting means for detecting a direction that a face in the face image detected by the face-image detecting means is facing; feature-position detecting means for detecting feature positions corresponding to features of the face from the face image detected by the face-image detecting means and the direction of the face detected by the face-direction detecting means; feature-value calculating means for calculating feature values at the feature positions detected by the feature-position detecting means; mapping means for mapping the feature values calculated by the feature-value calculating means, using predetermined mapping functions; and recognizing means for recognizing whether the face detected by the face-image detecting means is a registered face, using the feature values mapped by the mapping means and feature values registered in advance.