Robust Photo Retrieval Using World Semantics
Hugo Liu, Henry Lieberman · 2002
Photos annotated with textual keywords can be thought of as resembling documents, and querying for photos by keywords is akin to the information retrieval done by search engines. A common approach to making IR more robust involves query expansion using a thesaurus or other lexical resource. The chief limitation is that keyword expansions tend to operate on a word level, and expanded keywords are generally lexically motivated rather than conceptually motivated. In our photo domain, we propose a mechanism for robust retrieval by expanding the concepts depicted in the photos, thus going beyond lexical-based expansion. Because photos often depict places, situations and events in everyday life, concepts depicted in photos such as place, event, and activity can be expanded based on our “common sense ” notions of how concepts relate to each other in the real world. For example, given the concept “surfer ” and our common sense knowledge that surfers can be found at the beach, we might provide the additional concepts: “beach”, “waves”, “ocean”, and “surfboard”. This paper presents a mechanism for robust photo retrieval by expanding annotations using a world semantic resource. The resource is automatically constructed from a large-scale freely available corpus of commonsense knowledge. We discuss the challenges of building a semantic resource from a noisy corpus and applying the resource appropriately to the task. 1.