Typically cameras just output the H.264/H.265 stream(s) via rtsp, and optionally a video analytics metadata stream. The part that records video from one or more

Typically cameras just output the H.264/H.265 stream(s) via rtsp, and optionally a video analytics metadata stream. The part that records video from one or more cameras can be separate and is called a network video recorder (NVR). This split allows you to store several cameras' stuff in one place that is better physically protected and in a better form factor for having a hard drive, access a bunch of cameras' data easily under one UI even if they're made by different manufacturers, etc. I'm working on an open-source NVR: https://github.com/scottlamb/moonfire-nvr https://github.com/scottlamb/moonfire-nvr that is secure, will run on a Raspberry Pi 4, and has a good recording schema. I wouldn't describe the UI as nice yet, but I'd welcome help in making it so! There are some other open source NVRs (I see someone mentioned Shinobi). Probably a couple reasonably-priced commercial software options (people like Blue Iris, but it's Windows-only). Some commercial NAS devices have NVR support (eg Synology). Dedicated NVRs from manufacturers like Dahua/Hikvision (but my experience is they're awful). YMMV.