16. A method of automatically identifying portions of an image of a physical scene as depicting physical objects of predefined types in the physical scene, the method comprising the steps of: generating a set of image features from two-dimensional image data that was obtained by two-dimensionally imaging the physical scene; generating a set of geometric features from three-dimensional image data that was obtained by three-dimensionally measuring the physical scene coincidentally with the two-dimensional imaging of the physical scene; generating correspondences between image features in the generated set of image features and geometric features in the generated set of geometric features; identifying, based on a first subset of the image features, a first portion of the image of the physical scene as depicting a physical object of a first predefined type; selecting a first subset of the geometric features that corresponds to the first subset of the image features based on the generated correspondences; and determining, based on the first subset of the geometric features, that the identified first portion of the image does not actually depict a physical object of the first predefined type.
16. A method of automatically identifying portions of an image of a physical scene as depicting physical objects of predefined types in the physical scene, the method comprising the steps of: generating a set of image features from two-dimensional image data that was obtained by two-dimensionally imaging the physical scene; generating a set of geometric features from three-dimensional image data that was obtained by three-dimensionally measuring the physical scene coincidentally with the two-dimensional imaging of the physical scene; generating correspondences between image features in the generated set of image features and geometric features in the generated set of geometric features; identifying, based on a first subset of the image features, a first portion of the image of the physical scene as depicting a physical object of a first predefined type; selecting a first subset of the geometric features that corresponds to the first subset of the image features based on the generated correspondences; and determining, based on the first subset of the geometric features, that the identified first portion of the image does not actually depict a physical object of the first predefined type. 20. The method of claim 16 , wherein the correspondences between images features and geometric features comprise correspondences between multiple different geometric features and a single image feature.