Modeling the Perceptual Impact of Viewport Adaptation for Immersive Video

Immersive video offers the freedom to navigate inside the virtualized environment. Instead of streaming the entire bulky content, a viewport or field of view (FoV) adaptive streaming is preferred. We often stream the high-quality content within current viewport, but degraded-quality representation elsewhere, so as to reduce the network bandwidth consumption. We then could refine the quality when focusing to a new FoV. Therefore, in this work, we have attempted to model the perceptual response of the quality variations (through adapting the quantization and spatial resolution) with respect to the refinement duration, and reach at a product of two closed-form exponential functions that well explain the joint quantization and resolution induced quality impact. Analytical model is also cross-validated using another set of data with both Pearson and Spearman's rank rank correlations over 0.98. Our work would be devised to guide the bandwidth-quality optimized immersive video streaming.