The NNI query-by-Example system for MediaEval 2014

In this paper we describe the system proposed by NNI (NWPU- NTU-I2R) team for the QUESST task within the Mediaeval 2014 evaluation. To solve the problem, we used both dy- namic time warping (DTW) and symbolic search (SS) based approaches. The DTW system performs template match- ing using subsequence DTW algorithm and posterior repre- sentations. The symbolic search is performed on phone se- quences generated by phone recognizers. For both symbolic and DTW search, partial sequence matching is performed to reduce missing rate, especially for query type 2 and 3. Af- ter fusing 9 DTW systems, 7 symbolic systems, and query length side information, we obtained 0.6023 actual normal- ized cross entropy (actCnxe) for all queries combined. For type 3 complex queries, we achieved 0.7252 actCnxe.