From searching this forum I don't believe anybody's tried using ViewCam with Victure cameras. These are ultra-cheap Chinese cameras, that I think are just rebadged other brands (but I don't know which).
I'm using four PC420 cameras, and two PC730 cameras. All are set to ONVIF with static IPs. All work fine if accessed using VLC.
To cut a long story short, the PC420 cameras works fine in ViewCam with a "Manual Configuration" profile, and "RTSP (video and audio)" set as the format. Nothing else needs completing in the prefs dialog boxes.
I cannot get the PC730 cameras to work. I just see "Connecting..." forever, then sometimes , "No key frames recently". I've tried every configuration I can think of in the ViewCam preferences window.
VLC's info window when playing the streams shows exactly the same for both cameras:
H264 - MPEG-4 AVC (part 10) (h264) / PCM ALAW (alaw)
.. but with one difference. The troublesome PC730 cameras have 25 frame rate, while the PC420 cameras have 20.