Calibrating Photometric Stereo by Holistic Reflectance Symmetry Analysis

Zhe Wu, Ping Tan; The IEEE Conference on Computer Vision and Pattern Recognition (CVPR), 2013, pp. 1498-1505

Abstract


Under unknown directional lighting, the uncalibrated Lambertian photometric stereo algorithm recovers the shape of a smooth surface up to the generalized bas-relief (GBR) ambiguity. We resolve this ambiguity from the halfvector symmetry, which is observed in many isotropic materials. Under this symmetry, a 2D BRDF slice with low-rank structure can be obtained from an image, if the surface normals and light directions are correctly recovered. In general, this structure is destroyed by the GBR ambiguity. As a result, we can resolve the ambiguity by restoring this structure. We develop a simple algorithm of auto-calibration from separable homogeneous specular reflection of real images. Compared with previous methods, this method takes a holistic approach to exploiting reflectance symmetry and produces superior results.

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[bibtex]
@InProceedings{Wu_2013_CVPR,
author = {Wu, Zhe and Tan, Ping},
title = {Calibrating Photometric Stereo by Holistic Reflectance Symmetry Analysis},
booktitle = {The IEEE Conference on Computer Vision and Pattern Recognition (CVPR)},
month = {June},
year = {2013}
}