[Trisquel-users] Re : Pictures in backgrounds

[lcerf]

You can select a background in your home folder.  Writing in  
/usr/share/backgrounds requires administrative permissions.  If have such  
permission and really want to copy a file to /usr/share/backgrounds, open a  
terminal in the folder containing the file ("back.jpg" in my example) and  
execute:
$ sudo cp back.jpg /usr/share/backgrounds