Effects of audio reproduction methods on the sense of presence in audio-visual content

Abstract

The sense of presence is crucial for evaluating audio-visual equipment. To clarify the effects of audio reproduction methods on the sense, two experiments were conducted under audio-only and audio-visual conditions. Twelve scenes were recorded with a high-definition video camera while their sounds were recorded using a dummy head. In the audio-only condition, the recorded audio signals were reproduced with headphones by five methods: binaural reproduction with and without the headphone transfer function calibration, binaural reproduction with the joint stereo coding, stereophonic reproduction in which head-related transfer functions from two loudspeakers to the both ears were convolved to the binaural signals, and diotic reproduction in which the left and right channel signals were superimposed. Twenty subjects evaluated each stimulus using a Likert scale. In the audio-visual condition, the same experiment was performed while video signals were reproduced with a 65-inch display. In the audio-only condition, the effect of reproduction methods was significant, i.e. stimuli with the three binaural reproduction methods were evaluated as being higher presence than those with the other two methods. In the audio-visual condition, however, the effect was less prominent. These results suggest that spatial information of audio signals was compensated by visual information. [Work supported by NICT]