This is a slideshow in HTML / JS which shows random images / videos of an existing files list.
Online version available here.

• Random slideshow of HTML5 videos webm / mp4 / ogg and any images, including gif ;
• Keyboards controls (prev, next, pause, increasing/decreasing timer) ;

• UI for custom variables, and maybe more user-ajustable stuff (max-height, min-width, bottom or top, etc.) ;

I didn't find any soft able to display pictures including gif properly in a slideshow. XnView for instance isn't able to loop gif and will skip to the next file at the end of the animation.

Like i said, it's in html/js. Details and editable variables can be found in the js/main.js file. I'll copy details here too :

HOW IT WORKS
You need a .txt with one filepath you want to see / line. It can be any image format including gif, and any video format supported by html5. In Windows for instance, you can use something like this on a directory : dir "D:\Documents\Images" /A-D /S /b /-p /o:gen >List_Files.txt

NB : If you're using the script locally via file://, you may need to follow these advices.

CONTROLS
Left arrow : Previous file
Right arrow : Next file (random if not already existing)
Up/Down arrow : Increase/Decrease the timer
Spacebar : Pause (be careful to unfocus the "Browse" button first) Echap : Display/Hide the config window

Note the code is probably not great. I didn't code for a while.