VLC Player - Failed to open VDPAU backend libvdpau_nvidia.so
Solution 1:
The issue in this case was with the snap install of VLC player.
Removing the snap install with:
sudo snap remove vlc
Following it up with:
sudo apt-get remove --purge *vlc*
Install VLC with apt:
sudo apt-get install vlc
For another issue I had with openGL rendering of the video output, I removed/purged the 390.77 driver and added the ppa:graphics-driver
and installed 415.18.
Example of good log history after fix:
VLC media player 3.0.4 Vetinari (revision 3.0.4-0-gf615db6332)[000055963f262570] main libvlc: Running vlc with the default interface. Use 'cvlc' to use vlc without interface. [00007fb868c09430] avcodec decoder: Using NVIDIA VDPAU Driver Shared Library 415.18 Thu Nov 15 21:34:27 CST 2018 for hardware decoding
[00007fb868cc1d60] avcodec decoder: Using NVIDIA VDPAU Driver Shared Library 415.18 Thu Nov 15 21:34:27 CST 2018 for hardware decoding