Sensitivity to spatial details drops across the visual periphery, and hence video streaming systems that gracefully degrades quality away from the viewpoint of the observer, provides an optimum viewing experience with potentially large bitrate savings. As reaction latency is an important performance parameter of such systems, good prediction of future gaze locations at the transmission end is very important. A major research question here is: whether a gaze prediction model designed using a pristine undistorted video, is also able to predict the gaze pattern of users when they watch a distorted/ adaptively distorted version of the same video. With several improvements to existing gaze prediction schemes, in combination with a controlled subjective experiment, we confirm not only that HEVC coding distortions have no significant impact on the predictability of gaze patterns, but also that gaze prediction errors can be restricted to 1.5 degrees of viewing angle for a round trip delay of up to 200ms.
['Yashas Rai', 'Patrick Le Callet', 'Gene Cheung']
Role of HEVC coding artifacts on gaze prediction in interactive video streaming systems