Abstract: Edges in images of translucent objects are very different from edges in images of opaque objects. The physical causes for these differences are hard to characterize analytically and are not well understood. This paper considers one class of translucency edges—those caused by a discontinuity in surface orientation—and describes the physical causes of their appearance. We simulate thousands of translucency edge profiles using many different scattering material parameters, and we explain the resulting variety of edge patterns by qualitatively analyzing light transport. We also discuss the existence of shape and material metamers, or combinations of distinct shape or material parameters that generate the same edge profile. This knowledge is relevant to visual inference tasks that involve translucent objects, such as shape or material estimation.
Ioannis Gkioulekas, Bruce Walter, Edward H. Adelson, Kavita Bala, and Todd Zickler, "On the Appearance of Translucent Edges", IEEE Conference on Computer Vision and Pattern Recognition (CVPR), 2015.
[pdf] [supplementary] [poster]
Please click here for the dataset of about 45,000 rendered translucent edge intensity profiles described in the paper.