  Despite great recent advances in visual tracking, its further development,
including both algorithm design and evaluation, is limited due to lack of
dedicated large-scale benchmarks. To address this problem, we present LaSOT, a
high-quality Large-scale Single Object Tracking benchmark. LaSOT contains a
diverse selection of 85 object classes, and offers 1,550 totaling more than
3.87 million frames. Each video frame is carefully and manually annotated with
a bounding box. This makes LaSOT, to our knowledge, the largest densely
annotated tracking benchmark. Our goal in releasing LaSOT is to provide a
dedicated high quality platform for both training and evaluation of trackers.
The average video length of LaSOT is around 2,500 frames, where each video
contains various challenge factors that exist in real world video footage,such
as the targets disappearing and re-appearing. These longer video lengths allow
for the assessment of long-term trackers. To take advantage of the close
connection between visual appearance and natural language, we provide language
specification for each video in LaSOT. We believe such additions will allow for
future research to use linguistic features to improve tracking. Two protocols,
full-overlap and one-shot, are designated for flexible assessment of trackers.
We extensively evaluate 48 baseline trackers on LaSOT with in-depth analysis,
and results reveal that there still exists significant room for improvement.
The complete benchmark, tracking results as well as analysis are available at
http://vision.cs.stonybrook.edu/~lasot/.
