  Everyone "knows" that compressing a video will degrade the accuracy of object
tracking. Yet, a literature search on this topic reveals that there is very
little documented evidence for this presumed fact. Part of the reason is that,
until recently, there were no object tracking datasets for uncompressed video,
which made studying the effects of compression on tracking accuracy difficult.
In this paper, using a recently published dataset that contains tracking
annotations for uncompressed videos, we examined the degradation of tracking
accuracy due to video compression using rigorous statistical methods.
Specifically, we examined the impact of quantization parameter (QP) and motion
search range (MSR) on Multiple Object Tracking Accuracy (MOTA). The results
show that QP impacts MOTA at the 95% confidence level, while there is
insufficient evidence to claim that MSR impacts MOTA. Moreover, regression
analysis allows us to derive a quantitative relationship between MOTA and QP
for the specific tracker used in the experiments.
