Correlation-based rotational signature of planar binary objects

摘要

In this paper we introduce the affine spatial overlap operation denned as a generalization of the two-dimensional convolution and cross-correlation operations. Our attention is focused on the rotational overlap operation and some of its mathematical properties as well as its application to shape description. Based on the auto-rotational overlap operation, a one-dimensional signature is proposed as a shape representation for planar binary objects with bounded support. We provide illustrative examples of its digital computation using different binary objects. In addition, physical realization of the 2-D rotational overlap operation is demonstrated with a hybrid optical-digital system for real time processing. The experimental setup uses a microcomputer controlled high-precision rotatory stage for performing analog rotations at the input plane of an incoherent two lens correlator architecture.