JRS at Synchronization of Multi-user Event Media Task

The event synchronisation task addresses the problem of aligning media (i.e., photo and video) streams (“galleries”) from different users temporally and identifying coherent events in the streams. Our approach uses the visual similarity of image/key frame pairs based on full matching of SIFT descriptors with geometric verification. Based on the visual similarity and the given time information, a probabilistic algorithm is employed, where in each run a hypothesis is calculated for the set of time offsets with respect to the reference gallery. From the gathered hypotheses, the final set of time offsets is calculated as the medoid of all hypotheses.