  A long-term visual object tracking performance evaluation methodology and a
benchmark are proposed. Performance measures are designed by following a
long-term tracking definition to maximize the analysis probing strength. The
new measures outperform existing ones in interpretation potential and in better
distinguishing between different tracking behaviors. We show that these
measures generalize the short-term performance measures, thus linking the two
tracking problems. Furthermore, the new measures are highly robust to temporal
annotation sparsity and allow annotation of sequences hundreds of times longer
than in the current datasets without increasing manual annotation labor. A new
challenging dataset of carefully selected sequences with many target
disappearances is proposed. A new tracking taxonomy is proposed to position
trackers on the short-term/long-term spectrum. The benchmark contains an
extensive evaluation of the largest number of long-term tackers and comparison
to state-of-the-art short-term trackers. We analyze the influence of tracking
architecture implementations to long-term performance and explore various
re-detection strategies as well as influence of visual model update strategies
to long-term tracking drift. The methodology is integrated in the VOT toolkit
to automate experimental analysis and benchmarking and to facilitate future
development of long-term trackers.
