Some Experiments in Image Vectorization

The application of vectorization algorithms to digital images derived from natural scenes is discussed. It is argued that the fractal nature of these scenes precludes some of the savings in storage expected from vector over raster representation, although considerable savings still result. Experimental results are given. Algorithms for contour following, line thinning, and polygonal approximation well adapted to complex images are presented. Finally, the Map Manipulation System, an experimental program package designed to explore the interaction between vector and raster information, is described briefly. Introduction It is often convenient to transform digital images between raster format, in which the images are represented by two-dimensional arrays of intensity values, and some vector code, such as a set of polygonal approximations to the contours of homogeneous regions. Both representations have their advantages, and in many applications they coexist [ l ] . In this paper we refer to the operation of going from raster t