  Unsupervised video summarization plays an important role on digesting,
browsing, and searching the ever-growing videos every day, and the underlying
fine-grained semantic and motion information (i.e., objects of interest and
their key motions) in online videos has been barely touched. In this paper, we
investigate a pioneer research direction towards the fine-grained unsupervised
object-level video summarization. It can be distinguished from existing
pipelines in two aspects: extracting key motions of participated objects, and
learning to summarize in an unsupervised and online manner. To achieve this
goal, we propose a novel online motion Auto-Encoder (online motion-AE)
framework that functions on the super-segmented object motion clips.
Comprehensive experiments on a newly-collected surveillance dataset and public
datasets have demonstrated the effectiveness of our proposed method.
