This is actually a black and white photo!
What if I told you that the picture above is actually a black and white photo? Don't believe me? Take a closer look! At first glance, it really does look like a normal coloured image. But carefully look at the photo and you’ll start to realise that the image is actually black-and-white with many coloured lines.
This phenomenal image has left many netizens in awe and disbelief. How did we get fooled into seeing a fully coloured image when it was merely a few coloured stripes overlayed through a black-and-white photo?
This viral image was created by digital media artist and software developer Øyvind Kolås as a visual experiment. The image is actually an optical illusion known as a color assimilation grid illusion that achieves its effect by simply laying a grid of selectively coloured lines over an original black-and-white image.
So what is making us view this black-and-white image as a coloured image?
On Kolås’s page, he mentioned that “An over-saturated colored grid overlayed on a grayscale image causes the grayscale cells to be perceived as having color” and according to Bart Anderson, a vision scientist from University of Sydney, the illusion that we are experiencing isn’t out of the norm.
This illusion not only works with grids, but also with stripes and dots. Kolås has also played around with stripes and dots, and claimed that grids still works the best.
The usage of grids have similar analogy of farmers using red nets to brighten up the colour of their produce in consumers' eyes.
Here is an example of Kolås using dots to create the optical illusion, he mentioned on his page that "The raster of dots gives a nice analogy to halftoning as used in print, where color assimilation aids the optical mixture of colors that already happens before our visual system gets involved."
Netizens doubted and questioned Kolås about his work, claiming that it was due to the compression of a JPEG file, Kolås responded in his Patreon page, “This is not the exactly same as the way JPEG compression works, since in JPEG compression the lower resolution color signal is present for in every reconstructed pixel, in this illusion the reconstruction is happening in our eyes/mind,”
Amazingly, this effect does not end with static images, but also in videos.