What Colour Are These Circles? Mind-Boggling Optical Illusion Is Viral

A mind-bending optical illusion recently shared on Twitter has gone viral - and it's making people question their own eyes. The 'Confetti' illusion was created by David Novick, a computer and information science engineer. It shows 12 circles with multi-coloured horizontal stripes.

Take a quick glance at the picture, and the circles will appear green, red and purple. Look a little more carefully, and you will realise that all the 12 circles are the same light brown colour.

"A three-color confetti illusion with spheres, which appear to be yellowish, reddish, and purpleish but in fact have exactly the same light-brown base color," wrote Mr Novick while sharing the optical illusion on Twitter. He added that shrinking the image would result in an increase in the effect.

A three-color confetti illusion with spheres, which appear to be yellowish, reddish, and purpleish but in fact have exactly the same light-brown base color (RGB 255,188,144). Shrinking the image increases the effect. Original png file is at https://t.co/6r2PMbLMJc. pic.twitter.com/ro1zpVxLm2

— David Novick (@NovickProf) June 14, 2019

Confused? Don't believe your eyes? You're not alone. Here's how people reacted to the "mind-boggling" optical illusion:

Mind . . . Blown! https://t.co/V6tCOz3dZW

— Barry Ritholtz (@ritholtz) June 25, 2019

I don't believe it until I make some masks in Photoshop! pic.twitter.com/y5cFdF9Wla

— Wenzy (@ziyangwen) June 16, 2019

This is fantastic. I truly cannot believe my eyes. https://t.co/VlFLJn0rBR

— Kate Elizabeth Kiss (@KateElizabethK1) June 15, 2019

And if you want to see how exactly the illusion works, one helpful Twitter user shared an animation too:

OK, here it is... designed by @NovickProf, animation by @thehardmenpath. pic.twitter.com/T7N3H6V1pK

— thehardme (@thehardmenpath) June 16, 2019

So why do the brown circles appear red, purple and green? According to SYFY.com, this is called the Munker-White illusion, because of which the way we perceive colours changes according to the colours around them.

This, meanwhile, is not the only optical illusion to have gone viral recently. A picture that appears to show a beach, but is actually something quite different, also had people scratching their heads.