Metadata model for interactions of 3D objects

Fast development of software and hardware technologies, especially in the visualization field, drives the growth of advanced applications that employ three dimensional user interfaces. Cost and time efficient development of new interactive three dimensional systems requires reusable interactive 3D objects. Such objects have to be self-contained and associated with metadata, because metadata is required to automate searching for objects with specific properties. Object geometry and semantic metadata can be built with existing metadata standards like MPEG-7, while there is no solution for object interaction metadata. In the paper, a new approach to interaction metadata, called multimedia interaction model (MIM), is presented. With MIM an interaction is described not as communication between objects, but as a reaction of one object to events that happen in a three dimensional world. Following this point of view, interaction is decomposed into three elements: event, condition and action. Metadata descriptions that correspond to each of these interaction elements have different structures and employ a specific set of description tools. Such decomposition makes the MIM approach applicable to almost any interaction, which in effect allows using MIM as a universal tool for describing object interaction properties.