Parametric description of object motion using EMUs

Large scale deployment of digital multimedia applications requires effective and efficient image and video representations for indexing. We present a hierarchical representation of video objects based on their motion. The proposed representation enables both low and semantic level description of object motion. At the low level, we consider a parametric description of the dominant motion of video objects, and define elementary motion units (EMU) where the dominant motion of the object is coherent and does not undergo considerable change. A group of EMUs forms an action unit which carries semantic information. Interactions between objects are also considered by calculating the relative motion between objects in an object-based framework. Experimental results for retrieval of EMUs based on similarity of dominant object motion are demonstrated.