PKU-ICST at TRECVID 2012: Known-item Search Task

We participate in all two types of known-item search task of TRECVID 2012: automatic search and interactive search. This paper presents our approaches and results. We adopt three kinds of text information, which are XML documents, ASR and OCR. And we index and search the three kinds of pre-processed text individually with Lucene. In addition, the results are combined and re-ranked by two re-ranking approaches. We achieve the good performances, and official evaluation shows that our team is ranked 1 st in both automatic search and interactive search.