Perceptual Calibration for Immersive Display Environments

Abstract

The perception of objects, depth, and distance has been repeatedly shown to be divergent between virtual and physical environments. We hypothesize that many of these discrepancies stem from incorrect geometric viewing parameters, specifically that physical measurements of eye position are insufficiently precise to provide proper viewing parameters. In this paper, we introduce a perceptual calibration procedure derived from geometric models. While most research has used geometric models to predict perceptual errors, we instead use these models inversely to determine perceptually correct viewing parameters. We study the advantages of these new psychophysically determined viewing parameters compared to the commonly used measured viewing parameters in an experiment with 20 subjects. The perceptually calibrated viewing parameters for the subjects generally produced new virtual eye positions that were wider and deeper than standard practices would estimate. Our study shows that perceptually calibrated viewing parameters can significantly improve depth acuity, distance estimation, and the perception of shape.

A perceptual calibration method to ameliorate the phenomenon of non-size-constancy in hetereogeneous VR displays

“…Perceptual calibration is an alternative method that uses inverse geometric models to determine the perceptually correct viewing parameters ( [15], [22]) and, its application has shown to improve distance perception in CAVE systems [22]. The method is based on the idea of defining camera positions that are wider or deeper than the values obtained using standard calibration practices, with the purpose of influencing the perception of size and distance.…”

“…The method is based on the idea of defining camera positions that are wider or deeper than the values obtained using standard calibration practices, with the purpose of influencing the perception of size and distance. We develop our first approach based on the study developed in [22], and we extended it to support HMDs.…”

“…1). Perceptual calibration is based on the idea that perception in VR is distorted, and defining calibration parameters based on the viewer's eyes morphology is a simplistic approximation, since it depends on how the actual geometry is interpreted by the visual system which is out of observation ( [22], [15]). A typical perceptual calibration procedure generates a set of perceptual camera positions by adjusting the IPD and OCD dynamically, with the purpose of finding a set of virtual cameras positions that approximate the subject's spatial perception to the physical world.…”

“…Based on the study developed in [22], we requested subjects to judge the superimposition of a virtual box with a physical one with the same dimensions. Before starting the test, we measured the subject's physical IPD and we estimated an OCD equivalent to 5 cm (using the tracker position in the CAVE condition as reference).…”

Sensor-Display Registration for 3D Physical User Interaction Using a Flat-Panel Display

“…Similar situation may happen in a traditional CAVE system [5], which uses a magnetic or optical tracker as an input device. A common approach is to let a user locate some virtual markers with a real marker, to establish correspondences in both real and virtual coordinate systems [6], [7]. However, it depends on the user's perception, and requires laborious registration process.…”