Providing support for interaction with consistent multimedia presentations

Multimedia presentations are generally specified in terms of spatial and temporal relations between the media objects involved. Creation of these presentations, and interactions with them during their play-out, require an effective mechanism for handling the specifications dynamically. These specifications could result in inconsistencies, which need to be checked and resolved. Moreover, consistent presentations could become inconsistent due to interactions during the playout. Our main contribution is the design of an algorithm which aids in resolving these consistency issues dynamically and efficiently. The other salient features of our approach are a new composite spatio-temporal operator and an effective relaxation policy. We have developed a prototype which helps to study the effectiveness of the proposed approach. Thus, this paper presents an interactive multimedia presentation mechanism, which maintains a consistent and complete set of constraints during authoring and play-out of the presentation.