Color Time Petri Net for Interactive Adaptive Multimedia Objects

A composite multimedia object (cmo) is comprised of different media components such as text, video, audio and image, with a variety of constraints that must be adhered to. The constraints are 1) rendering relationships that comprise the temporal and spatial constraints between different components, 2) behavioral requirements that include the security and fidelity constraints on each component and, 3) user interactions on a set of related media components. Different users have different capabilities (e.g. age), characteristics (e.g. monitor size) and credentials (e.g. subscription to service). Our objective is to author an interactive adaptive cmo that renders itself correctly to different users. Therefore, it is important to guarantee the consistency of the cmo specifications in all possible scenarios. In this paper, we include the user interaction with temporal and spatio-temporal behavior in the specification of the adaptive cmo. We then check the consistency of user interaction specifications by transforming the specifications into a color time Petri net model. We perform a reachability analysis on the Petri net to identify inconsistencies. We then resolve the identified inconsistencies to have a consistent Petri net. A consistent Petri net presents an error-free interactive cmo that can adapt to different users, by guaranteeing that link user interactions are reachable for all eligible users.