In this paper, a method to compute 3D real world coordinates using 2D image from MS Kinect sensor was proposed for indoor navigation system. Nonlinearity in 2D image plane and mismatch between RGB and depth image were solved to calculate precise 3D real world coordinates. The experiments show that the proposed method can provide accurate 3D positions with 20 Hz output rate. The position error is less than 1% and standard deviation is less than 1 cm.

Keywords: Kinect, localization, RGB image, depth image, calibration