DYNAMIC ADJUSTMENT OF STEREO DISPLAY PARAMETERS

A review of the facts about human stereo vision lends to the conclusio n that the human stereo processing mechanism is very flexible in the p resence of other depth cues, Stereopsis seems to provide only local ad ditional depth information, rather than defining the overall three-dim ensional (3-D) geometry of a perceived scene, This paper reports on an experimental approach to adjusting stereo parameters automatically an d thereby providing a low eye strain, easily accommodated stereo view for computer graphics applications, To this end, the concept of virtua l eye separation is defined, Experiment 1 shows that dynamic changes i n virtual eye separation are not noticed if they occur over a period o f a few seconds, Experiment 2 shows that when subjects are given contr ol over their virtual eye separation, they change it depending on the amount of depth in the scene, Based partly on these results, an algori thm is presented for enhancing stereo depth cues for moving computer g enerated 3-D images, It has the effect of doubling the stereo depth in flat scenes and limiting the stereo depth for deep scenes, It also re duces the occurrence of double images and the discrepancy between focu s and vergence, The algorithm is applied dynamically in real time with an optional damping factor applied so the disparities never change to o abruptly, Finally, Experiment 3 provides a qualitative assessment of the algorithm with a dynamic ''flight'' over a digital elevation map.