Just in case anyone else finds this topic - I’ve also tried zoneminder, motioneye, shinobi, kerberos, blueiris (docker + wine ) and tried out NX Witness after finding this thread. The NX Witness support was pretty quick in getting back to me with this response:
Our partner Digital Watchdog sells and supports Network Optix’ IPVMS platform under the brand name DW Spectrum. You can get pricing and purchase licenses from the following online resellers:
Please note that DW Spectrum licenses do NOT work with Nx Witness. You will need to install DW Spectrum prior to activating the licenses that you purchase.
Looking at those links, seems like the per-camera license is ~$65-$80 depending on the day.
I’m still figuring out some more details from DW right now (how licenses work, api’s available, etc), but for the most part this looks like a really robust ideal software to run on a linux system with tons of support behind it. Granted i’m about 3 days into my 30 day trial, but i’m cautiously optimistic .