Denoising Time-of-flight Depth Maps Using Temporal Median Filter

In many types of 3D cameras, The Time-of-Flight (TOF) cameras have the advantages of simplicity for use and lower price for general public. The TOF cameras can obtain depth maps at video speed. However, the TOF cameras suffer from low resolution and high random noise. In this paper, we propose methods to reduce the random noise in depth maps captured by the TOF cameras. For each point in the noisy TOF depth map, we substitute the depth value with the median depth value of its corresponding points in temporally consecutive depth maps captured by the TOF cameras. The proposed methods require only the depth data captured by the TOF cameras without any extra information, such as illumination, geometric shape, or complex parameters. Experiments results suggest that the proposed temporal denoising methods can effective reduce the noise in TOF depth maps for up to 44 percent.