A Prime-Number-based Matrix strategy for efficient iconic indexing of symbolic pictures

摘要

In the previous approaches to represent pictorial data, as the complexity of the representation strategy is increased, the more spatial relationships can be represented, which also results in a more complex strategy for query processing and a limited types of queries that can be answered. In this paper, we propose an efficient iconic indexing scheme 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 relationships which are represented in 2D C-strings in a matrix, and an efficient module-based operation can be used to support pictorial query, spatial reasoning and similarity retrieval. In the proposed scheme, we classify 169 spatial relationships between two objects in 2D space into five spatial categories, and define a category rule for each of those five spatial categories. Those category rules are module-operation-based; therefore, they are efficient enough as compared to the previous approaches. Following those category rules, we propose algorithms to efficiently support spatial reasoning, picture queries and similarity retrieval based on a data structure of a Prime-Number-based Matrix (PN Matrix).