The Perception of Lightness in 3-D Curved Objects

Date
1995-08
DOI
Authors
Pessoa, Luiz
Mingolla, Ennio
Arend, Larry
Version
OA Version
Citation
Abstract
Lightness constancy requires the visual system to somehow "parse" the input scene into illumination and reflectance components. Experiments on the perception of lightness for 3-D curved objects show that human observers are able to perform such a decomposition for some scenes but not for others. Lightness constancy was quite good when a rich local gray level context was provided. Deviations occurred when both illumination and reflectance changed along the surface of the objects. Does the perception of a 3-D surface and illuminant layout help calibrate lightness judgements? Our results showed a small but consistent improvement between lightness matches on ellipsoid shapes compared to flat rectangle shapes under similar illumination conditions. Illumination change over 3-D forms is therefore taken into account in lightness perception.
Description
License
Copyright 1995 Boston University. Permission to copy without fee all or part of this material is granted provided that: 1. The copies are not made or distributed for direct commercial advantage; 2. the report title, author, document number, and release date appear, and notice is given that copying is by permission of BOSTON UNIVERSITY TRUSTEES. To copy otherwise, or to republish, requires a fee and / or special permission.