Query sensitive dynamic web video thumbnail generation

With the fast rising of the video sharing websites, the online video becomes an important media for people to share messages, interests, ideas, beliefs, etc. In this paper, we propose a novel approach to dynamically generate the web video thumbnails according to user´s query. Two issues are addressed: the video content representativeness of the selected video thumbnail, and the relationship between the selected video thumbnail and the user´s query. For the first issue the reinforcement based algorithm is adopted to rank the frames in each video. For the second issue the relevance model based method is employed to calculate the similarity between the video frames and the query keywords. The final video thumbnail is generated by linear fusion of the above two scores. Compared with the existing web video thumbnails, which only reflect the preference of the video owner, the thumbnails generated in our approach not only consider the video content representativeness of the frame, but also reflect the intention of the video searcher. In order to show the effectiveness of the proposed method, experiments are conducted on the videos selected from the video sharing website. Experimental results and subjective evaluations demonstrate that the proposed method is effective and can meet the user´s intention requirement.