Observer Compensation for Projective Distortion of Graphic Displays.
Abstract
Graphic displays can provide accurate representation of 3-dimensional space only if viewed from the geometric center of projection; other viewing conditions result in distortions of virtual space. We have proposed two processes by which the perceptual system discounts these distortions: an active compensation and a passive categorization. This report describes three studies which demonstrate the nature of these processes: (1) Observers made magnitude estimate judgements of the depth of unfamiliar, 7-sided objects. Distortions were induced by moving the center of projection. Judgements corresponded almost completely with hte distorted virtual space. Next, distortions were induced by moving the observer. No effect of the distortions were found in this situation--indicating perfect perceptual compensation. (2) Observers made magnitude estimates of the height, width, and depth of familiar, rectangular, parallelopipeds. Distortions were induced as in the earlier studies. Judgements did not correspond to the distorted virtual space, nor did they demonstrate any compensation. Results suggest that categorization of familiar objects affects perceptual compensation; and (3) Studies used the up-down transformed response method to estimate signal detection theory parameters. Judgments of familiar objects are not simply affected by response bias, rather sensitivity to distortions of familiar objects is extremely low and highly variable within observers.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 15, 1980
- Accession Number
- ADA087736
Entities
People
- Harry L. Chiesi
- Richard R. Rosinski
Organizations
- University of Pittsburgh