The mammalian visual system uses a layered approach to detect motion, one layer feeding information to the next. After light is detected on-center cells  establish areas of contrast, simple cells extract orientation specific information, and complex cells analyze this data across time.  This motion detection scheme can be modeled computationally; pixels yield color components in an R,G,B structure, on-center cells total that information to compare a center and a surround.  Simple cells match on-center information to a template for evaluation, and submit the results to complex cells.  Complex cells evaluate the simple cells' results across time and locate motion.