Video applications usually involve a large number of moving objects. Moving objects refer to semantic real-world entity definitions that are used to denote a coherent spatial region and be automatically computed by the continuity of spatial low-level features, such as color and motion. Spatial and temporal relationships among these objects should be efficiently supported and retrieved within a video authoring tool. In this paper we present several spatial, temporal and spatio-temporal relationships of interest and propose efficient indexing scheme, based on multidimensional spatial data structures, for video applications that involve objects. So, we emphasize on analyzing and interpreting video object motions for advanced video
application. To realize this objective the research in this field
is subdivided into two main directions: (1) Moving objects
description at the low levels: using the spatio-temporal
relationships to analyze and present the video object motions.
(2) Moving object description at the semantic level: Actions,
events and interactions of moving objects.