This paper presents our approach and results in the Search and Anchoring in Video Archives task at MediaEval 2015. The Search part aims at returning a ranked list of video segments that are relevant to a textual user query. The Anchoring part focuses on the automatic selection of video segments, from a list of videos, that can be used as anchors to encourage further exploration within the archive. Our approach consists in structuring each video into a hierarchy of topically focused fragments, to extract salient segments in the videos at dierent levels of details with precise jump-in points for them. These segments will be leveraged both to answer the queries and to create anchor segments, relying on content based analysis and comparisons. The algorithm deriving the hierarchical structure relies on the burstiness phenomenon in word occurrences which gives an advantage over the classical bag-of-words model.
['Anca-Roxana Simon', 'Guillaume Gravier', 'Pascale Sébillot']
IRISA at MediaEval 2015: Search and Anchoring in Video Archives Task.