1. A method for detecting proper motion of real-world objects in an image from an image capturing device, the method comprising the steps of: acquiring, by an image capturing device, a first image of an object at a first point in time and a second image at a second point in time; acquiring depth information for each pixel of the first image and the second image, computing a third image, based on the first image or the second image as well as estimated ego-motion of the image capturing device itself between the first point and the second point in time, wherein the ego-motion is estimated based on forward kinematics of the image capturing device and depth information for each pixel of the first image; computing an ego motion-compensated optical flow by comparing the second image and the third image; and determining proper motion of the object by evaluating the optical flow based on a likelihood that the optical flow and the estimated ego-motion are consistent with the same physical velocity.