To record size and shape of a room, researchers use a speaker, five microphones and some math
Determining a room’s dimensions no longer requires a tape measure. An algorithm that sorts through echoes to develop accurate maps of a room, detailed June 17 in the Proceedings of the National Academy of Sciences, may lead to better sound quality for teleconferences and online gaming.
Previous experimental setups of acoustic maps have always involved a speaker that emits a sound and multiple microphones that record the sound. Ideally, each microphone detects sound waves that bounce off a single wall. Then researchers can use the time the sound was recorded and the direction it came from to calculate the position of each wall and reconstruct the room.
But in practice tracking sound is messy, because most echoes take convoluted paths. They may have bounced off multiple walls and the floor before reaching the microphone.
The challenge, says computer scientist Ivan DokmaniÄ of the Swiss Federal Institute of Technology in Lausanne, was to cre