1. A method comprising: determining a shape context of a point on a surface of a scanned ear impression model; comparing said shape context with each of a plurality of average shape contexts of an ear impression shape atlas, wherein said ear impression shape atlas is a reference ear impression having a plurality of labeled regions corresponding to a plurality of anatomic features, and each of said plurality of average shape contexts is determined as an average of individual shape contexts determined for a plurality of points in a corresponding one of said plurality of labeled regions on said ear impression shape atlas; and determining as a function of said step of comparing that said point on said surface of said ear impression model is within a region on said surface of said ear impression model corresponding to one of said plurality of labeled regions on said ear impression shape atlas.