Structured light 3D Scanning in Global Illumination

We have designed structured light patterns that are resilient to individual global illumination effects using simple logical operations and tools from combinatorial mathematics. Scenes exhibiting multiple phenomena are handled by combining results from a small ensemble of such patterns. Our methods can be readily incorporated into existing scanning systems without a significant overhead in terms of capture time or hardware.

The scene shown below has significant global illumination in the form of interreflections and sub-surface scattering. Conventional Gray codes and phase-shifting result in errors at points receiving inter-reflections. Modulated phase-shifting produces errors on translucent fruits. In contrast, the depth map computed using our techniques is nearly error free. Please see the compilation of results below for more examples.

Publications

Structured Light 3D Scanning in the Presence of Global Illumination

Mohit Gupta, Amit Agrawal, Ashok Veeraraghavan, Srinivasa Narasimhan

Proc. CVPR 2011

A Practical Approach to 3D Scanning in the Presence of Interreflections, Subsurface Scattering and Defocus

Mohit Gupta, Amit Agrawal, Ashok Veeraraghavan, Srinivasa Narasimhan

International Journal of Computer Vision

Scene

Depth Map (Our Technique)

3D Visualization

Conventional Gray Codes

Modulated Phase Shifting

Resources

Presentation Slides