Modeling temporal aspects of visual and textual objects in multimedia databases

In this paper we face the problem of modeling temporal aspects of visual and related textual entities in multimedia databases, within the framework of an object-oriented temporal data model. We distinguish two different time aspects in multimedia visual data: the intrinsic time, i.e., the time managed according to the sequence of frames composing a visual data item, and the extrinsic time, i.e., the (valid) time of the real world represented by the visual data item. We propose also a three-layered approach for composing temporal visual data. Relationships between visual data and related textual data are then considered: we propose here a taxonomy for temporal textual observations on visual data, based on their temporal properties. Iii relating textual temporal data and visual data, rye consider rite existing constraints among their valid times, possibly given at different granularities and with indeterminacy.