some detail about the nvtracker generating unique ID for each object ?

After reading documentation, I don’t find the part about how the nvtracker generate the unique ID for each object in tracking.
so I want to know it.
Any message is appreciated!

The low level lib provide the capability to generate Tracker Id, currently DS has 3 low level lib used IOU NvDCF and KLT algorithms, you can refer section 2.2 for more details [url][{"num"%3A56%2C"gen"%3A0}%2C{"name"%3A"XYZ"}%2C106%2C223%2C0][/url]