Dahua NVR's support the same API as the cameras (along with supporting a channel# > 1).
I didn't know about this Dahua Integration partner program (DIPP) and that the link you provided listed a newer version of the
HTTP API (2.78) that I would love to get my hands on. Unfortunately that link requires a login, which I assume can only be obtained by being an Integration Partner.
They list 3 requirements for the lowest level of a "partner" (Silver).
- Sign the DIPP agreement and NDA
- Participate co-marketing activities with Dahua
- Regular support during the project
Compared to the old version of the API doc which has been publicly available for a long time, this kinda sucks. Sure hope we can find this API doc in the wild.