Ray-tracing codec for structured light 3D camera

In this paper, we present a new method for decoding pixel correspondences in structured light based 3D reconstruction, refer to here as Ray-Tracing codec. The key idea of Ray-Tracing codec is to correctly define the region boundaries in real number, for each layer of the Hierarchical Orthogonal Code (HOC) based on an accurate boundary estimator, and to inherit the correct region boundaries between layers sharing common boundaries. Furthermore, each region in lower layer is traced back to the upper layer for the correct correspondence between regions. This is an improvement over existing HOC decoding algorithms as the wrong decoded pixel correspondences can be greatly reduced. The experimental results have shown that the proposed Ray-Tracing codec significantly enhances the robustness and precision in depth imaging, compare with HOC and other well-known conventional approach. The proposed approach opens a greater feasibility of applying structured light based depth imaging to a 3D modeling of cluttered workspace for home service robots.