A PRIME-NUMBER-BASED MATRIX STRATEGY FOR EFFICIENT ICONIC INDEXING OFSYMBOLIC PICTURES

In the previous approaches to represent pictorial data, as the complex ity of the representation strategy is increased, the more spatial rela tionships can be represented, which also results in a more complex str ategy for query processing and a limited types of queries that can be answered. In this paper, we propose an efficient iconic indexing schem e called Prime-Number-based Matrix (PN Matrix) for symbolic pictures, which combines the advantages of the 2D C-string and the 9DLT matrix. Basically, the proposed strategy can represent those complex relations hips which are represented in 2D C-strings in a matrix, and an efficie nt module-based operation can be used to support pictorial query, spat ial reasoning and similarity retrieval. In the proposed scheme, we cla ssify 169 spatial relationships between two objects in 2D space into f ive spatial categories, and define a category rule for each of those f ive spatial categories. Those category rules are module-operation-base d; therefore, they are efficient enough as compared to the previous ap proaches. Following those category rules, we propose algorithms to eff iciently support spatial reasoning, picture queries and similarity ret rieval based on a data structure of a Prime-Number-based Matrix (PN Ma trix). (C) 1997 Pattern Recognition Society. Published by Elsevier Sci ence Ltd.