A Mult ichannel Storage Arrangement Scheme of Pictorial Databases for Concurrent Spatial Match Retrieval

K e y w o r d s 9 D L T representation, Parallel spatial match query, Pictorial database. 1. I N T R O D U C T I O N The fast progress of computer hardware and software technologies stimulates the endless requests for computer applications. In the last two decades, computers were taking a fast influence on people's life. Especially for the past few years, computers supported more powerful capability of picture-oriented applications such as multimedia applications for entertainment products, digital map of navigation supports system on an aircraft, and pattern recognition in artificial intelligent applications. Many picture-oriented applications involve lots of similar picture searching, and this kind of retrieval is known as spatial match retrieval [1,2]. There is much research related to the topic of spatial match retrieval such as [3-6]. A spatial match query is a searching request that retrieves pictures from a pictorial database by specifying some spatial relationships among the objects of a picture. The spatial relationships only focus on the bearings among objects without considering the distance. In practice, a real picture is denoted by a symbolic picture which extracts the spatial characteristics from the real picture. Therefore, the operational targets of spatial match query are symbolic pictures which, in the meanwhile, can further be used to facilitate the similar picture searching. Figure 1 is a simple symbolic picture. In that figure, A, B, C, D, and E are five different icons, and each icon represents an atom that relates to the object in the real picture. The spatial 0898-1221/00/$ see front mat ter (~) 2000 Elsevier Science Ltd. All rights reserved. Typeset by A h/eS-TEX PII: S0898-1221 (00)00057-2 240 C.-C. CHANG AND J.-J. SHEN match query which is relevant to the symbolic picture in Figure 1, might contain some spatial specification. For instance, A is to the north of B and to the northwest of C, and so on. For the sake of processing convenience, Chang et al. [2] proposed the 2D-string method, and Chang and LiE [7] proposed a 9-DLT representation to store the symbolic picture into a list form.