"Echolocation" can determine the shape of a room, and may even help solve crime.
A research team placed four microphones in a room in order to "hear" the echoes bouncing off the walls, they were able to build a 3-D model from this information, according to the BBC. Bats, dolphins, and even some blind humans are able to us this technique to "see" their surroundings.
The computer algorithm distinguishes between stronger and weaker echoes, and counts how many times the echo bounces around the room.
"Our software can build a 3D map of a simple, convex room with a precision of a few millimetres," said lead author of the study, Ivan Dokmanic from the Ecole Polytechnique Federale de Lausanne in Switzerland (EPFL). "Each microphone picks up the direct sound from the source, as well as the echoes arriving from various walls.
"The algorithm then compares the signal from each microphone. The infinitesimal lags that appear in the signals are used to calculate not only the distance between the microphones, but also the distance from each microphone to the walls and the sound source," he said.
The new echolocation software can be used in a number of applications. Architects designing a concert hall could easily measure the acoustics in the room by listening to how the echoes bounce around the room. The technology could also aid in the creation of virtual reality.
"If your eyes see and your ears hear something that doesn't correspond, your brain is confused and disorientated," Dokmanic said. "If you want to start a virtual design using sound, you could use this to create spaces that are realistic with respect to the sounds, because you would know the echoes."
Echolocation could help forensic researchers to create evidence when sound is a component of the crime scene. The program could show where an incriminating voice recording had taken place.
