Today’s digital SLR cameras usually have two distinct Autofocus systems — what we now think of as traditional AF you get through the optical viewfinder; and (usually) a separate AF system for focus using the LCD monitor to view your scene, when shooting with Live View or recording video. They’re very different:
A film ID No. consisting of a user-settable number ( two digits) and a film roll No. (three digits) is imprinted automatically on the film leader. The user-settable number can be used to identify which EOS-1V body you used (if you have multiple EOS-1V bodies) to shoot that roll. The film roll No. counts up each time you load a roll of film into the camera.
