I’ve run into problems getting VLC to work with miscellaneous devices on Manjaro and I believe I’ve finally figured out that some of the dependencies to the plugins weren’t getting installed. Here is how I figured this out.
Gives the error about “VLC is unable to open the MRL…”
Make sure your user is a member of the “video” group. If so, then run VLC in debug mode:
vlc v4l2:///dev/video0 --extraintf=http:logger --verbose=2 --file-logging --logfile=vlc-log.txt
In my vlc-log.txt log file there is was a line that indicated that the libv4l2 was not loading due to a dependency issue (you will probably find lots of other dependencies that could also be fixed). The specific line was:
main warning: cannot load module `/usr/lib/vlc/plugins/access/libv4l2_plugin.so' (libzvbi.so.0: cannot open shared object file: No such file or directory)
I then searched for that specific file with:
pacman -F libzvbi.so.0
Then simply installed it with
sudo pacman -S zvbi
vlc v4l2:///dev/video0 works and I can use my Celestron USB Microscope.