Yes, I run Linux Mint on two of my “home” machines. Also gentoo, slack, debian (and derivatives) and centos. Speaking to Vincent Batts, who is self proclaimed to be “OS agnostic”, makes me ponder trying to be even more OS agnostic myself, as long as that OS is either unix or something better. With Linux Mint, it took some time to discover where the login background images were called from and how to change them. Read on for a simple, yet non-elegant solution.
One bizzare thing about linux Mint is that many people will point you to Menu->Preferences->System Settings->Administration->Login Window to change the background images on the login page. Once there, after authentication one will be presented with the following screen:
One can see that “Mint-X” is the default theme, an that it would seem like one could change the backgrounds right there:
This of course, does not work. A number of recent blog posts and forums on the internet seem to point to files that do not exist on my Mint system (17.1 Cinnamon) or do nothing to change the background image.
Let me be clear, you can change the theme, and therefore the pictures, but if one wishes to add their own pictures, it becomes a problem. Where do the pictures go and how does one make Mint use them for the theme?
So, in Mint 17.1, the crude solution is to either choose a location for your pictures (probably your ~/backgrounds) or put them in the default location. If you are using the default theme, the default location for pictures is ( again on Mint 17.1): /usr/share/backgrounds/linuxmint-rebecca/
I put my desired pictures in that directory (a group I purchased from David Lanham, which are really great images). Now one needs to edit the file: /usr/share/mdm/html-themes/Mint-X/slideshow.conf
One must also be root to do this, so sudo vim /usr/share/mdm/html-themes/Mint-X/slideshow.conf (if you use emacs or nano or binary, that is fine also). In that file you will find a group of lines looking like this (they are uncommented):
You will note all of them say: file:///usr/share/backgrounds/linuxmint-rebecca/<some image>. Simply replicate those lines, but replace <some image> with your image filenames. Now comment out those default lines (by adding an octothorpe (#)) to the beginning of them so they look like:
Save and exit that file and now you will have your images on the login screen. Of course, you can delete those default lines and add your own if you wish, you are not required to comment out the old ones and leave them in place.