1. A method of pattern matching for recognition of objects within an image using a model defined by a set of one or more model primitives representative of large scale structures of an archetype, the method comprising steps of: deriving at least one target primitive representative of a large scale structure of the image; and for each target primitive: identifying any model primitives that at least partially match the target primitive; and for each identified model primitive, calculating a figure of merit indicative of a degree of correspondence between the target primitive and the model primitive.