VIREO/ECNU @ TRECVID 2013: A Video Dance of Detection, Recounting and Search with Motion Relativity and Concept Learning from Wild

The VIREO group participated in four tasks: instance search, multimedia event recounting, multimedia event detection, and semantic indexing. In this paper, we will present our approaches and discuss the evaluation results. Instance Search (INS): We submitted four runs in total, experimenting three search paradigms for particular objects retrieval: (1) an elastic spatial consistency checking method; (2) a background context weighting strategy; and (3) a re-ranking step based on objects mining. The first two approaches are similar as last year [1], while the last one is our new exploration. Our submissions are all based on BoW model and tailored for the INS task. In particular, we use Delaunay Triangulation (DT) to address the complex spatial transformations for non-planar and non-rigid queries; the lack of information for small query objects is tackled with context modeling; and object mining augments the results by exploring frequent instances in TV series. - F X NO vireo dt 2: BoW method + elastic spatial checking via DT. This run corresponds to our paradigm (1), which models elastic spatial structures as deformable graphs.