Patent ID: 8116575

Claim:
A computer implemented method for detecting an anomaly, comprising an act of causing a processor to perform operations of: generating a model for a normal class using a training image, the normal class representing normal objects in a common class, wherein the operation of generating a model for the normal class further comprises operations of: receiving a plurality of images representing the normal class, each image having an object in a common class; identifying a set of geometric landmarks in the object for use in registering the images; registering the images by warping the images so that the geometric landmarks coincide in each of the images in a warped configuration, the images now being a set of training images; performing an Eigenspace analysis on the training images to construct a low-dimensional image subspace model of the normal class; computing a distance between each of the training images and the low-dimensional image subspace model; and generating a probability distribution of distances from the normal class to the subspace model; receiving a novel image having an object in the common class; identifying a set of geometric landmarks in the object in the novel image for use in registering the image; registering the novel image by warping the image so that the geometric landmarks coincide in the novel image and the training image, resulting in a warped novel image having an object; generating a probability distribution of distances from an anomalous class to the subspace model; determining if the object in the warped novel image is anomalous by further performing operations of: computing a distance between the warped novel image and a subspace model; identifying a point of intersection between the probability distribution of the normal class and the probability distribution of the anomalous class, the point of intersection defining a threshold to be used in determining a likelihood of being anomalous; and determining if the distance satisfies the threshold to classify the object as anomalous or normal; and notifying an operator if the object in the warped novel image is determined to be anomalous.