How can I stop Finder from converting and loading videos to display in movie icons? I want movies to be displayed simply as movie icons.

But currently, and for the past few years, Finder loads (and if it is a strange format converts) the video and then displays an icon showing a still from the movie. That is very very annoying. How can I switch that off?
To turn off the Finder's icon preview feature:


Right click on the desktop > Choose 'Show View Options'
Uncheck 'Show icon preview'