Usage #1 (Queue Management)
You can draw a specific recording area and count waiting time of the first visitor in queue, so you can get the average processing time.
You can combine multiple sensors to create a complete picture of the queue and know the queue time of each visitor.
Usage #2 (Popularity Checking)
You can use one sensor and set multiple area to record the staying time of visitors inside each area respectively. As a result, you can know the popularity by comparing the average staying time and number of visitors
In exhibition, You can check how many people walk path your booth and how many people enter your booth so to create a Turn-in ratio (Total people walking pass: No. of people entering)