Perceptual evaluation of synthetic gaze jitter

Abstract

Eye movements are an essential part of non‐verbal behavior. Non‐player characters, as they occur in many games, communicate with the player through dialogue and non‐verbal behavior and can have a strong influence on player experience or even on gameplay. In this paper, we evaluate a procedural model designed to synthesize the subtleties of eye motion. More specifically, our model adds microsaccadic jitter and pupil unrest both modeled by 1/fα or pink noise to the saccadic main sequence. In a series of perceptual two‐alternative forced‐choice experiments, we explore the perceived naturalness of different parameters of pink noise by comparing synthesized motions to rendered motion of recorded eye movements at extreme close shot and close shot distances. Our results show that, on average, animations based on a procedural model with pink noise were perceived and evaluated as highly natural, whereas data‐driven motion without any jitter or with unfiltered jitter were consistently selected as the least natural in appearance.

Is the avatar scared? Pupil as a perceptual cue

“…Pink noise has been widely used to model biological motions. 45 Duchowski et al 45 and Krejtz et al 13 found that it can be used to model the subtle changes in pupil size. A similar result was found by Jörg et al 46 showing that adding pink noise to the pupil size and eyeball motions of different virtual characters created animations with similar perceived naturalness than a motion captured approach and perceived as significantly more natural than animations with only keyframed eyeball motions and pupil size changes without pink noise.…”

“…Previous research has focused on making the dynamics of the eyeball realistic, 9 as well as the motions of the eyelids. 10,11 With advances in eye tracking, there is now work on adding subtle pupil dynamics, such as pupil jitter 12,13 and pupil light reflex. 14 While this past research has performed perceptual studies to show that adding realistic dynamics to the eyeballs, eyelids, and pupils improves the perceived realism and naturalness of a virtual avatar, there has been little investigation into how cues in the eyes impact the perceived internal state of a virtual avatar.…”