Your camera has an SD card and says ONVIF, so why can't the NVR see the recordings?

[spb-andrey]

This one comes up a lot and the answer is never in the product listing.

ONVIF isn't one thing, it's a set of profiles, and cameras implement the ones they feel like. Almost everything with a network port does Profile S, which covers the live stream, discovery and basic settings. That's what people mean when a listing says ONVIF.

Reading what's already recorded on the camera's own card is Profile G. Different profile, different services (Recording, Search and Replay), and it's uncommon on cheap hardware. So the card fills up perfectly well and the only thing that can open those files is the vendor's own app, which is usually the reason someone wanted an NVR in the first place.

Two ways to find out before you buy. The conformance database on onvif.org lists what each model was actually certified for, and if a model isn't there at all, then ONVIF on the box is just the vendor's word. If the camera is already on your desk, point any ONVIF client at it and look at what GetServices returns. No Search and Replay in that list means no software is ever going to browse that card.

Worth knowing what you're missing, because Profile G is genuinely useful. The interesting part isn't playback, it's ANR. The camera keeps recording to its card while the network is down, and when the link comes back the recorder pulls the missing stretch and stitches it into the main archive. Cheap cameras leave you with a hole in your timeline instead, and you find out about it months later.

If your camera doesn't have it, the workaround most people land on is FTP. Nearly all of them can upload clips to a server you run, and while that's not the same thing (the camera decides when to send, and rarely retries if your server was down), it at least gets footage off the card and into one place.