Comparing Real & Synthetic Scenes using Human Judgements of Lightness

Abstract

Increased application of computer graphics in areas which demand highlevels of realism has made it necessary to examine the manner inwhich images are evaluated and validated. In this paper, we explorethe need for including the human observer in any process which attemptsto quantify the level of realism achieved by the rendering process,from measurement to display. We introduce a framework for measuringthe perceptual equivalence (from a lightness perception point ofview) between a real scene and a computer simulation of the samescene. Because this framework is based on psychophysical experiments,results are produced through study of vision from a human ratherthan a machine vision point of view. This framework can then be usedto evaluate, validate and compare rendering techniques.