1. A method for determining a number of transfer objects which move from a first sub-region of an observed region into a second sub-region of the observed region, comprising recording, using at least one sensor arrangement, a sequence of images of the observed region, and using a computation unit connected to the at least one sensor arrangement and programmed to conduct the steps of identifying objects in the images, determining positions of the objects, associating each of the objects, in accordance with their positions, either to the first sub-region or the second sub-region, associating a track with each of the objects, wherein the track is determined from positions of the object in the sequence of images, wherein the track has a starting position located either in the first sub-region or in the second sub-region, associating a memory state with each of the objects on the basis of its track wherein, with a given starting position of the track, the memory state is dependent on whether the respective object is associated with the first sub-region or the second sub-region, wherein the memory state is a number that, when the respective object transfers between the first sub-region and the second sub-region, is incremented by a first value, wherein a first memory state is present if the number is an odd multiple of the first value, and wherein a second memory state is present if the number is an even multiple of the first value, and taking into account multiple transfers of the same object between the first sub-region and the second sub-region when determining the number of transfer objects.