a method for automatically locating instances of a specified image structure in digital images , comprising the steps of : providing a digital image ; detecting simple features associated with the specified image structure in the digital image ; for each detected feature , searching , in its spatial neighborhood , for a second or a plural of other features associated with the specified image structure ; for each pair of plural of features detected , using an eigenvector classifier to distinguish the wanted features and the unwanted features by matching the eigenvector representation that is constructed from a set of training profiles ; and labeling those image regions that are found to be consistent with the specified image structure in the classifying step .