  We introduce VOCALExplore, a system designed to support users in building
domain-specific models over video datasets. VOCALExplore supports interactive
labeling sessions and trains models using user-supplied labels. VOCALExplore
maximizes model quality by automatically deciding how to select samples based
on observed skew in the collected labels. It also selects the optimal video
representations to use when training models by casting feature selection as a
rising bandit problem. Finally, VOCALExplore implements optimizations to
achieve low latency without sacrificing model performance. We demonstrate that
VOCALExplore achieves close to the best possible model quality given candidate
acquisition functions and feature extractors, and it does so with low visible
latency (~1 second per iteration) and no expensive preprocessing.
