Shape from Interreflections

Abstract

All shape-from-intensity methods assume that points in a scene are only illuminated by sources of light. Most scenes consist of concave surfaces and/or concavities that result from multiple objects in the scene. In such cases, points in the scene reflect light between themselves. In the presence of these interreflections, shape-from-intensity methods produce erroneous (pseudo) estimates of shape and reflectance. The pseudo shape and reflectance estimates, however, are shown to carry information about the actual shape and reflectance of the surface. An interative algorithm is presented that simultaneously recovers the actual shape and the actual reflectance from the pseudo estimates. The recovery algorithm works on Lambertian surfaces of arbitrary shape with possibly varying and unknown reflectance. The general behavior of th algorithm and its convergence properties are discussed. Both simulation as well as experimental results are included to demonstrate the accuracy and stability of the algorithm.

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Document Details

Document Type
Technical Report
Publication Date
Jul 01, 1990
Accession Number
ADA230116

Entities

People

  • Katsushi Ikeuchi
  • Shree K. Nayar
  • Takeo Kanade

Organizations

  • Carnegie Mellon University

Tags

Communities of Interest

  • Materials and Manufacturing Processes
  • Sensors

DTIC Thesaurus Topics

  • Accuracy
  • Algorithms
  • Computer Graphics
  • Convergence
  • Equations
  • Flux Density
  • Geometry
  • Graphics
  • Intensity
  • Light Sources
  • Radiance
  • Radiant Intensity
  • Recovery
  • Reflectance
  • Simulations
  • Three Dimensional
  • Two Dimensional

Readers

  • Computer Vision.
  • Finite Element Method (FEM) for solving Partial Differential Equations (PDEs)