The Best Illusion of the Year contest is sponsored by the Vision Science Society, an international organization dedicated to the study of vision and the brain.
This year's winner is akin to the Blue Dress brain-teaser that divided your social media feeds into warring factions not so long ago.
"Splitting Colors" by Belgian Mark Vergeer took first prize.
Second prize went to the "Ambiguous Garage Roof" by Kokichi Sugihara.
In third place, was "The Day it Rained on Lowry," Michael Pickard's animation of the classic painting "Returning from Work."
To see all the finalists, click here.