Provided is a method for determining depth motion relative to a time-of-flight camera in a scene sensed by the time-of-flight camera. The method includes determining a first auxiliary depth image from a first set of phase images out of a sequence of phase images of the scene. The sequence of phase images is taken by the time-of-flight camera for a single time-of-flight depth measurement. A second auxiliary depth image is determined from a second set of phase images out of the sequence of phase images. The phase images of the second set of phase images are different from the phase images of the first set of phase images. Information about depth motion relative to the time-of-flight camera for at least part of the scene is determined based on a comparison of depth values represented by pixels in the first auxiliary depth image and the second auxiliary depth image.