1. A method of processing image data, comprising the steps of: storing a three-dimensional cloud of points related to a scene; selecting a profile definable in a two-dimensional surface; and matching said profile with said cloud of points, within a plurality of regions thereof, thus obtaining a plurality of sets of data representing successive matched surface portions, wherein the matching step further comprises the steps of: defining a starting position of the profile in said cloud, and a range in the cloud, said range being adjacent to said starting position, and extending along a direction of extension away from said two-dimensional surface; determining a direction of matching, along which said profile substantially fits with cloud points within said range, said direction of matching and said profile defining a first set of data representing a matched surface portion, and an end position of the profile; and selectively repeating the defining and determining steps, with the starting position being derived from a preceding end position, until a selected condition is met.