Skewed stereo time-of-flight camera for translucent object imaging

• A new skewed stereo ToF camera for detecting and imaging translucent objects under minimal prior of environment
• Translucent region detection method
• Translucent region recovery method
• Extensive analysis and evaluations

Time-of-flight (ToF) depth cameras have widely been used in many applications such as 3D imaging, 3D reconstruction, human interaction and robot navigation. However, conventional depth cameras are incapable of imaging a translucent object which occupies a substantial portion of a real world scene. Such a limitation prohibits realistic imaging using depth cameras. In this work, we propose a new skewed stereo ToF camera for detecting and imaging translucent objects under minimal prior of environment. We find that the depth calculation of a ToF camera with a translucent object presents a systematic distortion due to the superposed reflected light ray observation from multiple surfaces. We propose to use a stereo ToF camera setup and derive a generalized depth imaging formulation for translucent objects. Distorted depth value is refined using an iterative optimization. Experimental evaluation shows that our proposed method reasonably recovers the depth image of translucent objects.