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Framework for Representing and Reasoning about Three-Dimensional Objects for Vision



E Walker, Martin Herman, T Kanade


The capabilities for representing and reasoning about three-dimensional objects are essential for knowledge-based, 3D photo-interpretation system that combine domain knowledge with image processing, as demonstrated by such systems as 3D Mosaic and Acronym. Three-dimensional representation of objects is necessary for many additional applications such as robot navigation and 3D change detection. Geometric reasoning is especially important, since geometric relationships between objects parts are a rich source of domain knowledge. A practical framework for geometric representation and reasoning must incorporate projections between a 2D image and a 3D scene, shape and surface properties of objects, and geometric and topological relationships between objects. In addition, it should allow easy modification and extension of the system''s domain knowledge and be flexible enough to organize its reasoning efficiently to take advantage of the current available knowledge. We are developing such a framework, called the 3D FORM (Frame-based Object Recognition and Modelling) System. This system uses frames to represent objects such as buildings and walls, geometric features such as lines and planes, and geometric relationships such as parallel lines. Active procedures attached to the frames dynamically compute values as needed. Since the order of processing is controlled largely by accessing objects'' slots, the system performs both top-down and bottom-up reasoning, depending on the current available knowledge. The FORM system is being implemented using the CMU-built Framekit tool in Common Lisp [3]. Examples of interpretation using a simple model of building as rectangular prism are presented.
Ai Magazine
9 No. 2


Geometric Reasoning, World Modeling


Walker, E. , Herman, M. and Kanade, T. (1988), Framework for Representing and Reasoning about Three-Dimensional Objects for Vision, Ai Magazine, [online], (Accessed April 12, 2024)
Created June 29, 1988, Updated October 12, 2021