A Survey of Visual Preprocessing and Shape Representation Techniques

Abstract. This survey summarizes many recent theories and methods proposed for visual preprocessing and shape representation. The survey brings together research from the fields of biology, psychology, computer science, electrical engineering, and most recently, neural networks. This report was motivated by the need to preprocess images for a sparse distributed memory (SDM), but the techniques presented herein may also prove useful for applying other associative memories to visual pattern recognition. The material of this survey is divided into three sections 1) an overview of biological visual processing. 2) methods of preprocessing (extracting parts of shape, texture, motion, and depth), and 3) shape representation and recognition (form invariance, primitives and structural descriptions, and theories of attention). Work reported herein was supported in part by Cooperative Agreement NCC 2-408 betwee