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What do reflections tell us about the shape of a mirror?

Savarese, Silvio and Fei-Fei, L. and Perona, Pietro (2004) What do reflections tell us about the shape of a mirror? In: APGV '04 Proceedings of the 1st Symposium on Applied perception in graphics and visualization. ACM , New York, NY, pp. 115-118. ISBN 1-58113-914-4.

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Three-dimensional shape may be perceived from static images. Contours, shading, texture gradients, perspective and occlusion are well-studied cues to this percept. When looking at a picture of a specular object, such as a silver vase, one additional cue is potentially available: a deformed picture of the reflected environment is seen in the surface of the object and the amount and type of deformation depend on its shape. Can specular reflections be used as a visual cue for shape perception? Our experiments show that our subjects are very poor at judging the shape of mirror surfaces in absence of other visual cues. However, for a considerable subset of the stimuli, subjects are highly consistent in their (most often wrong) perception. This observation leads us to the hypothesis that our subjects rather than 'computing' a percept from each image based on geometrical considerations, may be associating a shape to each pattern in a stereotypical way, akin to pattern-matching. This behavior is reasonable since, as suggested by our ideal observer analysis, the information available from specular reflections is ambiguous when the surrounding world is (partially) unknown.

Item Type:Book Section
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Perona, Pietro0000-0002-7583-5809
Additional Information:© 2004 ACM.
Subject Keywords:shape perception, specular reflections, mirror surfaces, shape from texture
Record Number:CaltechAUTHORS:20161215-152242958
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:72859
Deposited By: Kristin Buxton
Deposited On:15 Dec 2016 23:56
Last Modified:03 Oct 2019 16:22

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