A generalized prime-number-based matrix strategy for efficient iconic indexing of symbolic pictures

In this paper. we propose an efficient iconic indexing strategy called gene ralized prime-number-based matrix (GPN Matrix) for symbolic pictures, in wh ich each spatial relationship between any two objects is represented as a p roduct of some prime numbers from a set of 12 prime numbers and is recorded in a matrix. In the proposed strategy, we classify 169 spatial relationshi ps between two objects in 2D space into five spatial categories, and define a generalized category rule (based on module operations) for each of those five spatial categories. As compared to the prime-number-based matrix (PN Matrix) strategy (Chang and Yang, 1997), in which each spatial relationship between any two objects is represented as a product of some prime numbers from a set of 17 prime numbers, the GPN Matrix strategy has a smaller stora ge space requirement than the PN Matrix strategy. which also improves the q uery processing time. (C) 2001 Elsevier Science B.V. All rights reserved.