Using VMS like Network Optix with deepstream

I would like to implement something like this
Passing video frames from a video management system to deepstream test app to detect person or vehicles
Can someone help ?
VMS like network optix has options to implement custom plugins which can extract video frames. In this case how can I pass those video frames to deepstream app and detect objects

We have several implementations in Source Group
Please check if you can apply your case to existing one. Probably utilizing RTSP is the choice.