Expand this Topic clickable element to expand a topic
Skip to content
Optica Publishing Group

Shape from shading for multiple light sources

Not Accessible

Your library or personal account may give you access

Abstract

Many shape recovery algorithms—in particular, shape from shading (SFS)—are based on a point source at infinity or a uniform hemispheric source. It will be convenient and useful if we can perform SFS under indoor lights that may be spherical, cylindrical, or flat (ceiling lights) in shape in an uncontrolled environment. As a first step toward this goal we propose a light source model for each of the above shapes for performing SFS. In this study we give the derivation of the rectangular, spherical, and cylindrical light source models. In indoor environments the positions (usually on the ceiling or walls) of the light sources are known. Assuming that the target object is small relative to the distances from the sources, we have derived a reflectance map for the Lambertian surface of an object under a mixture of light sources of the above shapes. Hence the shape recovery can be performed by using the SFS technique. This is a significant step toward the application of SFS in uncontrolled practical environments under household or office lighting. This technique of shape recovery is verified by many examples of simulations and real experiments, and the results are good.

© 1999 Optical Society of America

Full Article  |  PDF Article
More Like This
Shape recovery from a color image for non-Lambertian surfaces

Ying-li Tian and H. T. Tsui
J. Opt. Soc. Am. A 14(2) 397-404 (1997)

Shape-from-shading on a cloudy day

M. S. Langer and S. W. Zucker
J. Opt. Soc. Am. A 11(2) 467-478 (1994)

Motion recovery in light-attenuating media from image-shading variations

C. H. Yu and S. Negahdaripour
J. Opt. Soc. Am. A 9(7) 1062-1071 (1992)

Cited By

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Figures (22)

You do not have subscription access to this journal. Figure files are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Tables (4)

You do not have subscription access to this journal. Article tables are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Equations (49)

You do not have subscription access to this journal. Equations are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Select as filters


Select Topics Cancel
© Copyright 2024 | Optica Publishing Group. All Rights Reserved