Information on the shape of an object is extracted by generating an image of the object, encoding and ordering the boundary points of the image, selecting points on the outermost portions of the boundary, partitioning the boundary at the selected points into segments of either a first or second kind...http://www.google.co.uk/patents/US4771469?utm_source=gb-gplus-sharePatent US4771469 - Means and method of representing an object shape by hierarchical boundary decomposition
