Defence of doctoral thesis in the field of Media Technology, M.Sc. Otto Puomio

Virtual acoustics bring concert halls to people’s living rooms 

MSc. Otto Puomio investigated in his doctoral thesis how environmental cues could be utilized in virtual acoustics. Environmental cues create the impression of the surrounding room to the listener. Also, by utilizing these cues, one can auralize an acoustic space with headphones or loudspeakers.

Puomio examined in his article dissertation how well environmental cues can be found with parametric sound capturing methods. Generally, room reproduction methods can be divided into linear and parametric methods. Linear methods utilize signals from a microphone array (i.e., a set of microphones with fixed relative locations) and combine them with a simple matrix multiplication to array independent form. Compared to linear methods, parametric methods are more sophisticated. In addition to an array independent storage, they also calculate other properties such as the direction of arrival and diffuseness of sound from the signal.

According to Puomio’s research, multiple parametric measurements allow determining the room shape and estimating the acoustic materials of the walls. Parametric measurements can even be used to reconstruct complex spaces which has not been possible with earlier methods.

However, parametric methods do not seem to reproduce the room comprehensively. The spatial impression is only accurate at measurement positions.

“Parametric methods work like a flashlight in a dark room; you can see one corner at a time properly, but not the whole room at once”, Puomio says.

When the possibilities of the methods become clearer and are developed further, they can be used to reproduce concert halls in home theaters or to warp room acoustics in virtual reality systems. By using these future devices, two people far away from each other can discuss and feel like they would be together in a similar soundscape.

Opponent: Doctor Philip W. Robinson, Meta Inc., Reality Labs Research Audio, USA

Custos: Professor Tapio Lokki, Aalto University School of Electrical Engineering, Department of Signal Processing and Acoustics

Contact information of the doctoral student: [email protected]

The public defence will be organized on campus and via Zoom. Link to the event

The dissertation is publicly displayed 10 days before the defence in the publication archive Aaltodoc of Aalto University. 

Electronic thesis (link will be added)