Changing login screen wallpaper

By trying the answer of Senio I had no luck. But with little modification I hit the jackpot :

sudo -i
xhost +SI:localuser:lightdm
su lightdm -s /bin/bash
gsettings set com.canonical.unity-greeter draw-user-backgrounds 'true'
gsettings set com.canonical.unity-greeter background 'path-to-image'
exit

path-to-image is actually the path where the image you want as log in screen wallpaper is stored e.g. : /usr/share/backgrounds/x.jpg

I tested it and it's working

I found this page which offers some tips regarding this problem : Ubuntu13.04 LighDM

Cheap and dirty solution: Got to Terminal, then:

sudo nautilus

Then use Nautilus to copy your preferred background to

/usr/share/backgrounds/

Then rename the image that is being used to backup-imagenameold.png Then rename your preferred image to the filename of the original background.

I know it's not clean or lean, but it does the job asap ;)

Cheers, Rüssel

Its very simple.

1. Open a terminal

2. become root and change current folder

   sudo su
   cd /usr/share/backgrounds/
   

3. Copy the picture file to this location

4. Change the file name to warty-final-ubuntu.png

That will change the login screen background image.

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