Extracting the Shape and Roughness of Specular Lobe Objects Using Four Light Photometric Stereo
IEEE Transactions on Pattern Analysis and Machine Intelligence
Surface curvature and shape reconstruction from unknown multiple illumination and integrability
Computer Vision and Image Understanding - Special issue on physics-based modeling and reasoning in computer vision
The Generic Bilinear Calibration-Estimation Problem
International Journal of Computer Vision
International Journal of Computer Vision
Bundle Adjustment - A Modern Synthesis
ICCV '99 Proceedings of the International Workshop on Vision Algorithms: Theory and Practice
CVPR '97 Proceedings of the 1997 Conference on Computer Vision and Pattern Recognition (CVPR '97)
Shape and albedo from multiple images using integrability
CVPR '97 Proceedings of the 1997 Conference on Computer Vision and Pattern Recognition (CVPR '97)
Illumination Cones for Recognition under Variable Lighting: Faces
CVPR '98 Proceedings of the IEEE Computer Society Conference on Computer Vision and Pattern Recognition
Estimation of Diffuse and Specular Appearance
ICCV '99 Proceedings of the International Conference on Computer Vision-Volume 2 - Volume 2
Recovering 3-D shape and reflectance from a small number of photographs
EGRW '03 Proceedings of the 14th Eurographics workshop on Rendering
International Journal of Computer Vision
Denoising images: non-linear leap-frog for shape and light-source recovery
Proceedings of the 11th international conference on Theoretical foundations of computer vision
ECCV'10 Proceedings of the 11th European conference on Computer vision: Part II
Toward a stratification of helmholtz stereopsis
CVPR'03 Proceedings of the 2003 IEEE computer society conference on Computer vision and pattern recognition
Capture and fusion of 3d surface texture
Multimedia Tools and Applications
Analysis of directional reflectance and surface orientation using fresnel theory
CIARP'05 Proceedings of the 10th Iberoamerican Congress conference on Progress in Pattern Recognition, Image Analysis and Applications
Binocular uncalibrated photometric stereo
ISVC'06 Proceedings of the Second international conference on Advances in Visual Computing - Volume Part I
Resolution-enhanced photometric stereo
ECCV'06 Proceedings of the 9th European conference on Computer Vision - Volume Part III
International Journal of Computer Vision
Auto-calibrating photometric stereo using ring light constraints
Machine Vision and Applications
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Lambertian photometric stereo with uncalibrated light directions and intensities determines the surface normals only up to an invertible linear transformation. We show that if object reflectance is a sum of Lambertian and specular terms, the ambiguity reduces into a 2dof group of transformations (compositions of isotropic scaling, rotation around the viewing vector, and change in coordinate frame handedness).Such ambiguity reduction is implied by the consistent viewpoint constraint which requires that all lights reflected around corresponding specular normals must give the same vector (the viewing direction). To employ the constraint, identification of specularities in images corresponding to four different point lights in general configuration suffices. When the consistent viewpoint constraint is combined with integrability constraint, binary convex/concave ambiguity composed with isotropic scaling results. The approach is verified experimentally.We observe that an analogical result applies to the case of uncalibrated geometric stereo with four affine cameras in a general configuration observing specularities from a single distant point light source.