The advantages of using a formal specification are in its precise definition of object properties and its declarative description of operations of a system. The Z notation is used widely in the literatures of formal system designs and the researches of language semantics. In line with the rapid growing of multimedia computation researches, we use the Z notation to design a multimedia database supports the reuse of multimedia presentations. In this paper, a formal specification of the database is presented. The database consists of two layers: the frame layer and the resource layer . A frame group in the first layer is the basic presentation unit to be reused. A resource group in the second layer is a collection of resources to be used by a frame, or a frame group. In the hierarchy, we use four type of links to group frames and/or resources. The database is built on the top of a commercial object- oriented database server and run under a windowing system.
Proceedings of 1996 International Computer Symposium -- International Conference on Distributed Systems, Software Engineering, and Database Systems，頁52-59