Have a OWSOO or Floureon D6008D-F CCTV DVR?

For an RTSP stream, try:

rtsp://<IP ADDRESS>:8854/live<CHANNEL NO>.264?user=<USERNAME>&passwd=<PASSWORD>

And sometimes the channel number is twice what you think (I think 1 = CH1 low quality, 2 = CH1 high quality, 3 = CH2 low quality, etc.).

Discovered by using Chrome / Vivaldi to inspect the page source once logged into the admin console at the IP address of the DVR (Which uses NETWORK logins as per the on-screen setup, not ADMIN logins!).