An Immersive Audiovisual Simulation Framework Based on 360° Video and Spatial Audio for Built Environment Perception Evaluation

Conventional laboratory-based soundscape evaluations often rely on static images and audio playback, which may provide limited visual dynamics, spatial auditory information, and interactive experience. This study developed an interactive audiovisual simulation system that integrates 360° video with spatial audio for controlled soundscape evaluation. Visual stimuli were presented on a monitor, with viewing direction controlled using a mouse in the 360° video condition. A laboratory experiment compared four scenarios combining two visual presentation modes—static photographs and 360° video—with the presence or absence of background sound recorded on site. Spatial audio was used in all four scenarios. Thirty-eight participants were recruited, and data from 36 participants with normal hearing and normal or corrected-to-normal vision were included in the final analysis. Participants evaluated visual perception, auditory perception, spatial perception, perceived realism, and overall perception across four audiovisual scenarios. Wilcoxon signed-rank tests showed that without background sound, the 360° video condition received significantly higher ratings for visual perception, perceived realism, and overall perception. With background sound, significantly higher ratings were observed for visual perception, auditory perception, spatial perception, perceived realism, and overall perception. For overall perception, the effect sizes were r = 0.379 without background sound and r = 0.668 with background sound. These findings indicate that combining panoramic visual presentation with dynamically rendered spatial audio can provide a more comprehensive perceptual representation of environmental scenes than conventional photograph-based methods. The proposed system offers a controllable and efficient approach for multisensory soundscape and built-environment evaluation. Further comparisons with in situ evaluations across different populations and settings are needed to assess its broader applicability.