Impossible shadows and the shadow correspondence problem

Mamassian, P., (2004) Impossible shadows and the shadow correspondence problem. Perception, 33, pp. 1279-1290. (doi: 10.1068/p5280)

Full text not currently available from Enlighten.

Abstract

Shadows cast by objects contain potentially useful information about the location of these objects in the scene as well as their surface reflectance. However, before the visual system can use this information, it has to solve the shadow correspondence problem, that is to match the objects with their respective shadows. In the first experiment, it is shown that the estimate of the light source position is affected by a gradual luminance ramp added to the image. In the second experiment, it is shown that observers process impossible shadow images as if they ignored the local features of the objects. All together, the results suggest that the visual system solves the shadow correspondence problem by relying on a coarse representation of the scene.

Item Type:Articles
Status:Published
Refereed:Yes
Glasgow Author(s) Enlighten ID:UNSPECIFIED
Authors: Mamassian, P.,
College/School:College of Science and Engineering > School of Psychology
Journal Name:Perception

University Staff: Request a correction | Enlighten Editors: Update this record