The Influence of Stereoscopy on the Sound Mixing of Movies: A Study on the Front/Rear Balance of Ambience

摘要

Few psychoacoustic studies have been carried out about the influence of stereoscopy on the sound mixing of movies. Yet very different opinions can be found in the cinema industry. Some argue that sound needs to be mixed differently for stereoscopic movies while others pretend that this influence is negligible. The present study focuses on the perception of ambience. Eight sequences were presented in a theater to 44 subjects, in their non-stereoscopic version and their stereoscopic version, with several different sound mixes. For each presentation, the subjects had to judge to what extent the mix sounded frontal or "surround." The goal was to verify whether stereoscopy had an influence on the perception of the front/rear balance of ambience. Results showed that this influence was weak (2 sequences out of 8), as suggested by a preliminary experiment conducted in a mixing auditorium, in which subjects had to mix the front/rear balance of several sequences themselves. A third experiment was conducted to verify if the sequences that were significantly influenced by stereoscopy corresponded to the sequences whose differences between s-3D and 2D versions were the most important in terms of perceived visual depth, yet no substantial correlation could be found.