Robust Structured Light with Efficient Redundant Codes

Structured light (SL) systems acquire high-fidelity 3D geometry with active illumination projection. Conventional systems exhibit challenges when working in environments with strong ambient illumination. This paper studies a general-purposed solution to improve the robustness of SL by projecting a redundant number of patterns. Despite sacrificing the signal-noise-ratio at each frame, projected signals become more distinguishable from errors. Thus, the geometry can be recovered easily. We systematically analyze the redundant SL code design rules to achieve high accuracy with minimum redundancy. Based on the more reliable correspondence cost volume and the natural image prior, we integrate spatial context-aware disparity estimators into our system to further boost performance. We also demonstrate the application of such techniques in iterative error detection and refinement. We demonstrate significant performance improvements of efficient redundant code SL systems in both simulations and challenging real-world scenes.