Depth image enhancement for Kinect using region growing and bilateral filter

Microsoft´s Kinect as a recent 3D sensor has attracted considerable research attention in the fields of computer vision and pattern recognition. But its depth image suffers from the problem of poor accuracy caused by invalid pixels, noise and unmatched edges. In this paper, an efficient approach is proposed to improve the quality of Kinect´s depth image. Using its corresponding color image, the pixels with wrong depth values are detected and removed using a region growing method. To accurately estimate the values of invalid pixels, a joint bilateral filter is used to fill the holes. Considering the special noise property of Kinect sensor, an adaptive bilateral filter is proposed to effectively reduce the noise of the depth image. Experimental results show that the proposed method significantly improves the quality of depth image by successfully filling the holes, eliminating the unmatched edges and reducing the noise.