Compositionality, MDL Priors, and Object Recognition

Images are ambiguous at each of many levels of a contextual hi(cid:173) erarchy. Nevertheless, the high-level interpretation of most scenes is unambiguous, as evidenced by the superior performance of hu(cid:173) mans. This observation argues for global vision models, such as de(cid:173) formable templates. Unfortunately, such models are computation(cid:173) ally intractable for unconstrained problems. We propose a composi(cid:173) tional model in which primitives are recursively composed, subject to syntactic restrictions, to form tree-structured objects and object groupings.