| Abstract: | The spatial relationships among pictorial objects are important spatial characteristics in image database systems. Based on the concept of 9-DLT representation, we propose a new method for effective storage utilization and picture retrieval. First, we transform a symbolic picture into a set of triples associated with pairwise spatial relationships among objects. Then, an associated normalized signature record with nine attributes is specified. Finally, each normalized record of this image database can be well allocated by using our proposed multiple key hashing scheme and can be fast accessed for spatial match retrieval. The performance formula for spatial picture retrieval is presented and the theoretically optimal solutions to the bit lengths of all the attributes are derived in certain case. Also, we give a systematic method to solve the feasible bit lengths for the attributes based on the method proposed by Chang. © 1997 John Wiley & Sons, Inc. |
