An ordinary camera could soon take photos of things that are out of sight, thanks to algorithms that interpret how light bounces off a wall.
“Normally, when light bounces off rough surfaces, like walls, it scrambles the scene into a messy blur,” says Wenwen Li at the University of Science and Technology of China, Hefei. “Our goal was to ‘unscramble’ that blur and recover the hidden scene. Think of it like turning a rough wall into a mirror.”
The method involves mapping the geometry and reflectance of the wall surface by taking many images under different lighting conditions, so the researchers could predict how each bump and groove would distort reflected light. Once they had created a digital model of the surface, the team devised equations to reconstruct a hidden image from the scrambled light pattern
Li and her colleagues have successfully demonstrated real-time imaging at 25 frames per second using an ordinary camera, like one found in a smartphone. more
