Viridian is a front-end for an Ampache server (see http://ampache.org). Viridian is written for Python 3 using the PyGTK bindings.
Up until version 1.2 Viridian was released under the GPL 3, that has changed going forward to the BSD 3 Clause license. (see LICENSE for more details).
You can run Viridian out of this directory by simply invoking it over the command line
$ ./viridian
You can also install it with
# python setup.py install
If you have used Viridian before and found that an update has messed it up, open Viridian and go to Edit -> Preferences -> System and hit "Reset Everything."
You can also do this manually by executing
~$ rm -r ~/.viridian