First off, I've been browsing here for some time, but I've just registered so I'm sorry if I'm breaking any etiquette or conventions on posting.

I ran across goofwear's tool to extract videos and photos from Samsung Motion Photos and thought it was useful. But I really wanted something that I'd be able to throw a whole album of motion photos at, rather than doing one at a time with this or the share app. I looked at the .bat file they used and implemented the same technique in C, so it could quickly process many photos. It's written with some direct Win32 API calls, so it's pretty much Windows only though making a cross platform command line version without the open dialog would be trivial. It is a simple program though, so it should work fine on Linux or Mac through Wine.

Here's the exe.
See the main page of that Github repository for more complete instructions and full source.