In this paper we describe our retrieval system and experiments performed for the automatic search task in TRECVid 2007. We submitted the following six automatic runs:
• F A 1 DCU-TextOnly6: Baseline run using only ASR/MT text features.
• F A 1 DCU-ImgBaseline4: Baseline visual expert only run, no ASR/MT used.
Made use of query-time generation of retrieval expert coefficients for fusion.
• F A 2 DCU-ImgOnlyEnt5: Automatic generation of retrieval expert coefficients for fusion at index time.
• F A 2 DCU-imgOnlyEntHigh3: Combination of coefficient generation which combined the coefficients generated by the query-time approach, and the index-time approach, with greater weight given to the index-time coefficient.
• F A 2 DCU-imgOnlyEntAuto2: As above, except that greater weight is given to the query-time coefficient that was generated.
• F A 2 DCU-autoMixed1: Query-time expert coefficient generation that used both visual and text experts.