Immersive Audio : Simulated Acoustics for Interactive Experiences

A key aspect of immersive audio is realistic acoustics. To get plausible acoustics for an environment the impulse response can be generated using acoustic simulations and should ideally be updated in real-time for interactive applications. In this thesis the listening experience of sound generated with an interactive sound propagation engine was explored and compared to spatial sound produced with a static impulse response. The aim was to evaluate the sound experience for applications outside of virtual reality, with computational cost in consideration. This was done by conducting a user study where the participants got to interact and compare the two sound methods in different environments. The study was performed using a custom developed application integrated with a pre-existing sound propagation engine. The results from the user study showed no obvious perceptive difference between the two sound rendering methods that could justify the extra computations. Overall there was even a slight preference for the stereo method that used a static impulse response. However, there were qualities to both sound rendering methods that were preferred depending on the environment. Another thing that was investigated in the work of this thesis was how the varying accuracy of localization of sound in different directions can be used in acoustic ray tracing algorithms. An alternative sampling method was developed that uses a biased distribution based on spatial resolution of human hearing instead of traditional uniform sampling. The computation time of the random sampling phase increases, but could potentially reduce the number of ray samples needed.Examensarbetet är utfört vid Institutionen för teknik och naturvetenskap (ITN) vid Tekniska fakulteten, Linköpings universitet