Open source software for generic POE NVR surveillance hardware?

Hello all, long time lurker and viewer…

I think the title says most of what I am asking. Does anyone know of any projects to replace the software that ships with almost every generic Chinese NVR device? I know it is a lot more secure to buy cameras, isolate them on another network and use another computer to host them but you just can’t compete with the cost-effectiveness of some of these kits…

The one I am looking at uses a Hi3536D processor/chipset. Any insight from anyone else who has tried this would be appreciated.

Thanks,
Newlove

Edit: I found this, but it isn’t quite what I am looking for, more just for making minor changes to existing FW, but its something: github -dot- com/zzHAMZAzz/Custom-Firmware-For-Chinese-CCTV-DVR