Cover thumbnailer is a small Python script which displays music album covers in nautilus, preview of pictures which are in a folder and more.

The script fits in nautilus like any other thumbnailer of the GNOME thumbnail factory; so you don't have to run it manually to generate thumbnails.

sudo add-apt-repository ppa:flozz/flozz
sudo apt-get update
sudo apt-get install cover-thumbnailer

You got it installed, now that his is configured, the Ubuntu menu select:

System> Preferences> Cover Thumbnailer

Add button to add folders to customize

 reset

killall nautilus

if you've noticed this change xD I hope that works for them to get worked mie source
I see that this software is not the manager

LINKS HOME

http://software.flogisoft.com/cover-thumbnailer/en/#screenshots