I want my computer to be in hibernation/sleep mode, and in this state, show a video/slideshow on the output screen. It’s not practical for me to switch the input with a raspberry pi or something, I just need it to run from the same system, perhaps dual booting into an operating system that’s purely for a video/slideshow?
Or maybe having the thing play from the kernel on boot, so I can then press a button to continue launching into windows, and I always just restart back into that state by default?
Or a separate computer just for the screensaver and use some type of switch with 2 inputs to share a monitor. A Pi is cheap enough to be used for looping video or slide show