Translucent surface detection by raycasting through multiple depth images.

Time-of-flight depth camera assumes that target scene consists of opaque surfaces. Therefore, any translucent object causing multipath problem in depth calculation cannot be appropriately reconstructed. If we are able to detect translucent surface under time-of-flight principle, depth map obtained from opaque region will be more reliable. Translucent surface can be recovered by separate approach afterhand. In this paper, we propose a translucent surface detection method from multiple depth images obtained at different viewpoints. First, multiple depth maps are registered in a 3D space based on camera transformations. Our method classifies surfaces into three types: opaque, translucent, and not determined surface. Raycasting through registered depth maps investigates overlapped surfaces identifying respective surface types. Experimental evaluation on both synthetic 3D models and real translucent object shows promising translucent surface detection results.