gpicview is a gui image viewer, similar to microsoft's image viewer.
You can preview, rotate an image etc.

Documentation

homepage http://lxde.sourceforge.net/gpicview/

Configuration

pacman -S xdg-utils
xdg-mime default gpicview.desktop `grep 'MimeType=' /usr/share/applications/gpicview.desktop | sed -e 's/.*=//' -e 's/;/ /g'`