App developed to map rooms using sound waves

Science News : To determine the dimensions of a room without use of a tape measure, researchers have used a speaker, five microphones, and a mathematical algorithm. As they explain in their paper published in the Proceedings of the National Academy of Sciences, Ivan DokmaniÄ of the Swiss Federal Institute of Technology in Lausanne and coworkers were able to sift through the multiple echoes bouncing off the walls and ceiling of a convex polyhedral room, group the echoes by which surface they bounced off of, and use that data to accurately describe the interior. Such a technique could be used to improve teleconferencing and online video gaming by minimizing echoes. The group is now working to refine the technique so that rooms could be mapped with a cellphone.