Visual Comfort and Fatigue in Stereoscopy
The development of three-dimensional (3D) video has impacted each part of the transmission chain, from acquisition to reproduction. It also strongly impacts user experience through the sensation of perceived depth. In this context, the Quality of Experience (QoE) [QUA 12] may be defined using three major factors [LAM 11]: visual quality, which refers to the quality of each view taken separately and corresponds to quality evaluated in terms of two-dimensional (2D) viewing; quality of the depth effect, qualified by a variety of indicators such as the reproduction quality of the 3D scene and the sense of presence induced by the 3D effect; and visual fatigue and visual (dis)comfort, often induced by technical constraints related to viewing stereoscopic content.
While recent progress in terms of capture and reproduction has enabled the use of high-quality 3D content according to the first two criteria (visual quality and quality of the depth effect), fatigue and discomfort continue to present significant limitations in the deployment of 3D video. Certain studies have shown that users tend to prefer the 2D version of a video to its 3D equivalent in cases where the latter may induce fatigue or discomfort [BAR 10].
In this chapter, we will provide an overview of visual fatigue and discomfort, both in terms of the mechanisms involved in the human visual system (HVS) and in terms of 3D content and processing technologies. ...