Resource Constrained Multimedia Event Detection

We present a study comparing the cost and efficiency tradeoffs of multiple features for multimedia event detection. Low-level as well as semantic features are a critical part of contemporary multimedia and computer vision research. Arguably, combinations of multiple feature sets have been a major reason for recent progress in the field, not just as a low dimensional representations of multimedia data, but also as a means to semantically summarize images and videos. However, their efficacy for complex event recognition in unconstrained videos on standardized datasets has not been systematically studied. In this paper, we evaluate the accuracy and contribution of more than 10 multi-modality features, including semantic and low-level video representations, using two newly released NIST TRECVID Multimedia Event Detection (MED) open source datasets, i.e. MEDTEST and KINDREDTEST, which contain more than 1000 hours of videos. Contrasting multiple performance metrics, such as average precision, probability of missed detection and minimum normalized detection cost, we propose a framework to balance the trade-off between accuracy and computational cost. This study provides an empirical foundation for selecting feature sets that are capable of dealing with large-scale data with limited computational resources and are likely to produce superior multimedia event detection accuracy. This framework also applies to other resource limited multimedia analysis such as selecting/fusing multiple classifiers and different representations of each feature set.