1. A method for representing an object appearing in an image, comprising: identifying at least one object outline; determining a curvature scale space representation for said outline to generate peak coordinates for the outline curvature scale space representation, wherein said peak coordinates are determined using a plural stage filter that produces derivative curves representative of said outline by convolving said object outline; and ordering said peak coordinates, by selecting highest peak value and associated highest peak coordinates and ordering remaining peak coordinates in decreasing peak height, to generate a shape descriptor for said outline.