In this paper, a new method to compute eigenimages in principal component a
nalysis (PCA) based vision systems is presented. It is called the mosaic im
age method. Tn this method, the object is represented as a collection of fe
atures and their relative positions (topology). This is a local and global
method. Although this method is created to account for the occlusion proble
m, it is found that the resulting representation is better than that obtain
ed using the traditional optimum representation. A simple algorithm for rec
ognition based on the new representation is proposed. Extensive experiments
are conducted. More than 110,000 test images with varying degree of occlus
ion are used to test the proposed method. It is found that the new method c
an accommodate up to 53% occluded parts with a recognition rate of more tha
n 95%. To our knowledge, this is the best result in the presence of occlusi
on ire PCA-based vision systems. (C) 1999 Pattern Recognition Society. Publ
ished by Elsevier Science Ltd. All rights reserved.