Impact Analysis of Foveation and Depth on the Perceptual Quality of Immersive Visual Content With Fixed Viewport

With the rapid development of devices for virtual reality, massive amounts of multimedia data have been produced to enrich the immersive experience. To construct vivid virtual reality, high-resolution content is required to achieve a good user experience. With the limitations of hardware capability, efficient data compression is one of the keys to addressing the current dilemma. In our opinion, visual perception is a promising strategy for addressing this problem. In this study, the impact of human visual perception in immersive environment is studied. Two hypotheses accounting for their impact on the quality of immersive videos at a fixed viewport are proposed and validated by subjective evaluation and analysis. A series of videos are created with various blur distortions based on the stimulus triggered by depth perception and the rapid falloff of acuity in the peripheral vision. Stereoscopic videos with imposed blur distortions arranged with different severities are evaluated subjectively in an immersive viewing environment. We then follow statistical approaches to examine the collected subjective quality distributions to discuss the feasibility of video compression based on processed videos. To improve encoding efficiency, a heuristic mechanism for immersive visual content compression is proposed. We examine a simple compression framework to demonstrate that the proposed hypotheses are applicable for practical video compression.