Spatio-temporal Block Model for Video Indexation Assistance

In the video indexing framework, we have developed a user assistance system in order to define concept models (i.e semantic index) according to features automatically extracted from the video. Because the manual indexing is a long and tedious task, we propose to focus the user attention on pre-selected prototypes that a priori correspond to the searched concepts. The proposed system is decomposed in three steps. In the first one, some basic spatio-temporal blocks are extracted from the video, a particular block being associated to a particular property of one feature. In the second step, a Question/Answer system allows the user to define links between basic blocks in order to define concept block models. And finally, some concept blocks are extracted and proposed as prototypes of the concepts. In this paper, we present the two first steps, particularly the block structure, illustrated by an example of video indexing that corresponds to the concept running in