Wide range stereo time-of-flight camera

Time-of-Flight cameras provide real-time depth information at each pixel. These cameras, however, suffer from modular errors, recording shortened distance measurements if the objects are farther than a certain maximum range. Previous error-correction methods use either a single depth map or successively acquired multi-frequency depth maps. In general, they are prone to incorrect range extension results when the scene is discontinuous or when the camera or objects are moving. Our method based on a stereo Time-of-Flight camera deals with moving cameras and objects by acquiring a pair of depth maps simultaneously. Challenges caused by noise and different viewpoints are resolved by an iterative Markov random field optimization technique that delivers the consistent recovery of actual depth values beyond the maximum range. The experiments show that the proposed method extends the range use of Time-of-Flight cameras beyond twice.

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