Shape and light directions from shading and polarization

Trung Thanh Ngo, Hajime Nagahara, Rin-Ichiro Taniguchi

Research output: Chapter in Book/Report/Conference proceedingConference contribution

20 Citations (Scopus)

Abstract

We introduce a method to recover the shape of a smooth dielectric object from polarization images taken with a light source from different directions. We present two constraints on shading and polarization and use both in a single optimization scheme. This integration is motivated by the fact that photometric stereo and polarization-based methods have complementary abilities. The polarization-based method can give strong cues for the surface orientation and refractive index, which are independent of the light direction. However, it has ambiguities in selecting between two ambiguous choices of the surface orientation, in the relationship between refractive index and zenith angle (observing angle), and limited performance for surface points with small zenith angles, where the polarization effect is weak. In contrast, photometric stereo method with multiple light sources can disambiguate the surface orientation and give a strong relationship between the surface normals and light directions. However, it has limited performance for large zenith angles, refractive index estimation, and faces the ambiguity in case the light direction is unknown. Taking their advantages, our proposed method can recover the surface normals for both small and large zenith angles, the light directions, and the refractive indexes of the object. The proposed method is successfully evaluated by simulation and real-world experiments.

Original languageEnglish
Title of host publicationIEEE Conference on Computer Vision and Pattern Recognition, CVPR 2015
PublisherIEEE Computer Society
Pages2310-2318
Number of pages9
Volume07-12-June-2015
ISBN (Electronic)9781467369640
DOIs
Publication statusPublished - Oct 14 2015
EventIEEE Conference on Computer Vision and Pattern Recognition, CVPR 2015 - Boston, United States
Duration: Jun 7 2015Jun 12 2015

Other

OtherIEEE Conference on Computer Vision and Pattern Recognition, CVPR 2015
CountryUnited States
CityBoston
Period6/7/156/12/15

Fingerprint

Polarization
Refractive index
Light sources
Experiments

All Science Journal Classification (ASJC) codes

  • Software
  • Computer Vision and Pattern Recognition

Cite this

Ngo, T. T., Nagahara, H., & Taniguchi, R-I. (2015). Shape and light directions from shading and polarization. In IEEE Conference on Computer Vision and Pattern Recognition, CVPR 2015 (Vol. 07-12-June-2015, pp. 2310-2318). [7298844] IEEE Computer Society. https://doi.org/10.1109/CVPR.2015.7298844

Shape and light directions from shading and polarization. / Ngo, Trung Thanh; Nagahara, Hajime; Taniguchi, Rin-Ichiro.

IEEE Conference on Computer Vision and Pattern Recognition, CVPR 2015. Vol. 07-12-June-2015 IEEE Computer Society, 2015. p. 2310-2318 7298844.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Ngo, TT, Nagahara, H & Taniguchi, R-I 2015, Shape and light directions from shading and polarization. in IEEE Conference on Computer Vision and Pattern Recognition, CVPR 2015. vol. 07-12-June-2015, 7298844, IEEE Computer Society, pp. 2310-2318, IEEE Conference on Computer Vision and Pattern Recognition, CVPR 2015, Boston, United States, 6/7/15. https://doi.org/10.1109/CVPR.2015.7298844
Ngo TT, Nagahara H, Taniguchi R-I. Shape and light directions from shading and polarization. In IEEE Conference on Computer Vision and Pattern Recognition, CVPR 2015. Vol. 07-12-June-2015. IEEE Computer Society. 2015. p. 2310-2318. 7298844 https://doi.org/10.1109/CVPR.2015.7298844
Ngo, Trung Thanh ; Nagahara, Hajime ; Taniguchi, Rin-Ichiro. / Shape and light directions from shading and polarization. IEEE Conference on Computer Vision and Pattern Recognition, CVPR 2015. Vol. 07-12-June-2015 IEEE Computer Society, 2015. pp. 2310-2318
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