  We propose an unsupervised visual tracking method in this paper. Different
from existing approaches using extensive annotated data for supervised
learning, our CNN model is trained on large-scale unlabeled videos in an
unsupervised manner. Our motivation is that a robust tracker should be
effective in both the forward and backward predictions (i.e., the tracker can
forward localize the target object in successive frames and backtrace to its
initial position in the first frame). We build our framework on a Siamese
correlation filter network, which is trained using unlabeled raw videos.
Meanwhile, we propose a multiple-frame validation method and a cost-sensitive
loss to facilitate unsupervised learning. Without bells and whistles, the
proposed unsupervised tracker achieves the baseline accuracy of fully
supervised trackers, which require complete and accurate labels during
training. Furthermore, unsupervised framework exhibits a potential in
leveraging unlabeled or weakly labeled data to further improve the tracking
accuracy.
