At least one of an area to protect and an area to ignore are marked using a visual indicator. The area to protect and the area to ignore are in proximity to a moveable barrier operator system. Visual inputs from a camera representative of the visual indicator are received and evaluated to automatically distinguish between the area to protect and the area to ignore. An evaluation area of the camera is limited so as to coincide with substantially only with the area to protect. Thereafter, it is determined whether an obstruction exists in the evaluation area of the camera. The evaluation area may be recorded and used for future determinations as to whether obstructions exist in the pathway of the barrier.