The invention relates to a method for determining the displacement of a vehicle in an environment. According to said method: at least part of the environment is recorded by means of an imaging device that is fixed on the vehicle using snapshots; at least two snapshots are evaluated to determine the optical flows of pixels; reference points, which appear stationary form the point of view of the imaging device, are determined from the optical flows; and the reference points are combined to form an observation quantity. New reference points for the observation quantity are dynamically added using a first algorithm and existing reference points are dynamically removed from the observation quantity using a second algorithm. The invention also relates to a device (30) for carrying out said method.