https://team.openipc.org/ipcam_dms/ (note the english translated link)
Be sure to firewall your cameras on your router to only intranet, do not let them access internet or they phone home
(you can let them sync time by capturing ITP requests and running your own service on your router)
But if you've hardened it even a little bit with something as easy as not letting it communicate off your intranet, well that can prevent ugly discoveries later
If you need offsite remote camera access you can always carve out a tunnel
This seems to be a thing for the commercial broadcast space:
* https://en.wikipedia.org/wiki/VISCA_Protocol
As opposed to the more security (residential?) camera protocol of:
* https://en.wikipedia.org/wiki/ONVIF
* Comparison: https://ikancorp.com/choosing-the-right-ptz-control-protocol...
We also got hammered by a patent troll because apparently, the math behind stitching fisheye lenses into a flat video plane is somehow patented.