|
ICT
GL
| Circularly Polarized Spherical Illumination Reflectometry | ACM SIGGRAPH Asia 2010 |
| Abhijeet Ghosh Tongbo Chen Pieter Peers Cyrus A. Wilson Paul Debevec |
| University of Southern California, Institute for Creative Technologies |
Renderings under environmental illumination of subjects with spatially varying reflectance acquired using circularly polarized spherical illumination.
Abstract:
We present a novel method for surface reflectometry from a few observations of a scene under a single uniform spherical field of circularly polarized illumination. The method is based on a novel analysis of the Stokes reflectance field of circularly polarized spherical illumination and yields per-pixel estimates of diffuse albedo, specular albedo, index of refraction, and specular roughness of isotropic BRDFs. To infer these reflectance parameters, we measure the Stokes parameters of the reflected light at each pixel by taking four photographs of the scene, consisting of three photographs with differently oriented linear polarizers in front of the camera, and one additional photograph with a circular polarizer. The method only assumes knowledge of surface orientation, for which we make a few additional photometric measurements. We verify our method with three different lighting setups, ranging from specialized to off-theshelf hardware, which project either discrete or continuous fields of spherical illumination. Our technique offers several benefits: it estimates a more detailed model of per-pixel surface reflectance parameters than previous work, it requires a relatively small number of measurements, it is applicable to a wide range of material types, and it is completely viewpoint independent.
Material:
SIGGRAPH Asia 2010 Paper:
- CPSIR_SIGGRAPH_Asia2010.pdf, 29.1 MB. ( Adobe Acrobat )
SIGGRAPH Asia 2010 Video:
- PolSphericalIllumination_SIGAsia2010_H264.mp4, 26.1 MB. ( Quicktime )
Related Projects:
- Surface Reflectometry:
- Specular Roughness and Anisotropy from Second Order Gradients,
Eurographics Symposium on Rendering 2009 - Practical Modeling and Acquisition of Layered Facial Reflectance , ACM SIGGRAPH Asia 2008
- High-Resolution Face Scanning, Eurographics Symposium on Rendering 2007
- Linear Light Source Reflectometry , SIGGRAPH 2003 Conference Proceedings
- Specular Roughness and Anisotropy from Second Order Gradients,
- Light Stage 1:
- Acquiring the Reflectance Field of a Human Face, SIGGRAPH 2000
- Facial Reflectance Field Demo, SIGGRAPH 2000 Creative Applications Laboratory
- Realistic Human Face Scanning and Rendering, ICT Graphics Lab 2001