Multigraph-Based Query-Independent Learning for Video Search

Most of the existing learning-based methods for video search take query examples as ¿positive¿ and build a model for each query. These methods, referred to as query-dependent, only achieve limited success as users are mostly reluctant to provide enough query examples. To address this problem, we propose a novel query-independent learning approach based on multigraph to video search, which learns the relevance information existing in the query-shot pairs. The proposed approach, named MG-QIL, is more general and suitable for a real-world video search system as the learned relevance is independent of any queries. Specifically, MG-QIL constructs multiple graphs, including a main-graph covering all the pairs and a set of subgraphs covering the pairs within the same query. The pairs in the main-graph are connected in terms of
relational similarity
, while the pairs in the subgraphs for the same query are connected in terms of
attributional similarity
. The relevance labels are then propagated in the multiple graphs until convergence. We conducted extensive experiments on automatic search tasks over the TRECVID 2005-2007 benchmark and the results show a superior performance to state-of-the-art approaches to video search. Furthermore, when applied to video search reranking, MG-QIL can also achieve significant and consistent improvement over a text search baseline.