@netbox, you ere right, it is done via VLC
@Gary, I had completely forgotten that I had made
this little tutorial in April last year for the basic setup. But there are a few more things you have to do:
1. set your normal desktop background to a single picture - any pic from your picture files. If you have a folder with several pictures that change e.g. every 15 minutes, the picture change will knock out the video on the sceen.
2. In VLC, you have to click on this Icon (e.g. in Playlist) in order to get the loop.
3. Make a playlist of your setup and put a shortcut at a place where you can access it easily - e.g. your dock or in a toolbar. That way you can easily start the video from the shortcut when you reboot or when it gets knocked out - which happens sometimes for some reason that I have not yet determined.
I have set that shortcut to open in Admin mode (in Priorities > advanced) hoping that the VLC process gets a higher priority and that lower priority processes cannot knock it out. But I am not 100% sure whether that has the dsesired effect. Seems to do the trick by me, but that may be accidental
4.
If you want to get out of it, right click on the VLC icon in the taskbar and Close VLC. In case you later want to use VLC for "normal" operation, you have to reset the Output to Default and Save it.
5. What also amazed me in the process was that a scrrenshot pasted into Paint would be animated like. It is .png format picture with 241KB. I did not know that .png could be animated like .gif .
6. You should also know that your screen will then operate in basic mode and any settings you may have made (e.g. increase the DPI) will not work. I have also noticed that the Magnifier works only in Dock mode, but that is probably not a big problem for most people.