On the use of the Karhunen-Loeve transform and expansion matching for generalized feature detection

A novel generalized feature extraction method based on the expansion matching (EXM) method and the Karhunen-Loeve (KL) transform is presented. This yields an efficient method to locate a large variety of features with a single pass of parallel filtering operations. The EXM method is used to design optimal detectors for different features. The KL representation is used to define an optimal basis for representing these EXM feature detectors with minimum truncation error. Input images are then analyzed with the resulting KL bases. The KL coefficients obtained from the analysis are used to efficiently reconstruct the response due to any combination of feature detectors. The method is successfully applied to real images and extracts a variety of arc and edge features as well as more complex junction features formed by combining two or more arcs or line features.