A direct method on camera’s ego-motion estimation using normal flows

In this paper, we propose a novel method to estimate the camera’s ego-motion parameters by directly using the normal flows. Normal flows, the projection of the optical flows along the direction of the gradient of image intensity, could be calculated directly from the image sequence without any artificial assumptions about the captured scene. Different from many traditional approaches which tackle the problem by establishing motion correspondences or by estimating optical flows, our proposed method could obtain the motion parameters directly by using the information of spatio-temporal gradient of the image intensity. Hence, our method requires no specific assumptions about the captured scene, such as the smoothness constraint, continuity constraint, distinct features appearing in the scene and etc.. Our method has been experimentally tested by using both synthetic image data and real image sequences. The experimental results demonstrate that our proposed method is feasible and reliable.