If you have a DVD copied to hard disk:
> dvdbackup -M -i /dev/scd0 -o directory
you can play it using
> ogle directory/DVDVOLUME
(where DVDVOLUME depends on the disc).
You cannot select this directory in the okle GUI though,
since the open dialog allows you to select only _files_,
not _directories_. This despite the fact that ogle would be
able to play this URL if it got it.