Look at the image below. What do you see? A colored photo, albeit a little washed out? Wrong answer. The truth is, the photo you see here is actually a black and white photo. The the t-shirt of the subjects only appeared to have color because of the colored grid lines overlaid on it. The colored grids tricked our brain into seeing color where in fact there are nothing but gray scale shades. Pretty mind-blowing stuff, don’t you think?
This is a black and white photograph. Only the lines have colour.— Lionel Page (@page_eco) July 27, 2019
What you “see” is what your ? predicts the reality to be, given the imperfect information it gets. pic.twitter.com/gwttlcC2Zw
However, as the unnecessary large featured image above proves, this size of gridlines only works if the image is of low resolution. I supposed we will need a tighter grid to bring out the effect for large images. Below is another example created by Twitter user Kyle Mathewson (@MathKyle).
Implemented this in matlab if anyone want to try: https://t.co/u3UnCWTa6u pic.twitter.com/5NLqijITZY— Kyle Mathewson (@MathKyle) July 28, 2019
This color trick reminds me of the viral dress that sparked a debate on whether it was blue and black or white and gold in 2015. Though, there was no manipulation on “The Dress” that made different people see different colors. Anyways, the human mind is a mysterious piece of hardware. It can learn to ignore things like, for example, floaters in our eyes or the partial view of the nose, that will otherwise bother some people.
Image: “2011-07-12-Railway People” by Chuwa (Francis) is licensed under CC BY-SA 2.0, color illusion remix by Øyvind Kolås.