TY - CONF T1 - Pictorial query trees for query specification in image databases T2 - Fourteenth International Conference on Pattern Recognition, 1998. Proceedings Y1 - 1998 A1 - Soffer,A. A1 - Samet, Hanan A1 - Zotkin,Dmitry N KW - Automation KW - complex queries KW - Computer science KW - content-based retrieval KW - Database systems KW - database-image objects KW - Educational institutions KW - Electrical capacitance tomography KW - grammars KW - Image databases KW - Image matching KW - parsing KW - pictorial query trees KW - Postal services KW - query specification KW - query-image objects KW - spatial constraints KW - syntax KW - visual databases AB - A technique that enables specifying complex queries in image databases using pictorial query trees is presented. The leaves of a pictorial query tree correspond to individual pictorial queries that specify which objects should appear in the target images as well as how many occurrences of each object are required. In addition, the minimum required certainty of matching between query-image objects and database-image objects, as well as spatial constraints that specify bounds on the distance between objects and the relative direction between them are also specified. Internal nodes in the query tree represent logical operations (AND, OR, XOR) and their negations on the set of pictorial queries (or subtrees) represented by its children. The syntax of query trees is described. Algorithms for processing individual pictorial queries and for parsing and computing the overall result of a pictorial query tree are outlined JA - Fourteenth International Conference on Pattern Recognition, 1998. Proceedings PB - IEEE VL - 1 SN - 0-8186-8512-3 M3 - 10.1109/ICPR.1998.711383 ER -