free safe mp4 to jpg converter

I need a simple, easy to use, free piece of software that does nothing more than convert every frame of a series of short (2 min max) mp4 files into a folder of jpg files.

On a previous computer I used the DVDFreeStudio subapp, and it worked fine. I thought I'd use that again -- but now the install software is being flagged by Malwarebytes as PUP, and I'm concerned they've added stuff to the install I don't want.

Am I overreacting, and should just ignore the PUP flag? Or is there a safer alternative out there?

Edit: I should add that I have a bunch I'd like to run a batch on, and I VASTLY prefer GUI to command line.