cv.jit.centroids centroids are a very cheap and robust way of doing motion tracking. Centroids, or center of mass, are the coordinates of the point where the number of ON pixels left of the x value is equal to the number of ON pixels to the right, and the number of pixels over the y value equals the number below. If there is only a single object in an image, centroids are a very cheap and robust way of doing motion tracking. Note that the centroids do not necessarily fall on an ON pixel, for instance in the case of a U-shaped object. Since the mass is used to calculate the centroids, cv.jit.centroids will also return this value from its second outlet.

from the library : cv.jit Format : External Environment : jitter / max / msp freeware Max 4.x http://www.iamas.ac.jp/~jovan02/cv/download.html