On the Reproduction of Motion Parallax in Videocommunications

Abstract

The paper addresses the question whether reproducing motion parallax increases the extent of telepresence in videocommunications. Motion parallax is defined as the change of the view due to the observer's movements. It was hypothesized that reproducing motion parallax (a) leads to more precise depth judgments by providing further depth cues, (b) allows ‘interactive viewing’, i.e. the observer can actively explore the visual scene by changing his/her position, and (c) compensates for stereoscopic “apparent movements”. In a Human Factors study, two videoconferencing set-ups providing motion parallax (one stereoscopic and one monoscopic version) were compared with two set-ups (monoscopic and stereoscopic) without motion parallax. Each set-up was used and rated by 32 subjects. The results supported the hypotheses only in part. Even though there was some evidence for more “spatial presence” and for a greater explorability of the scene through motion parallax, the compensation of apparent movements could not be achieved.