It's almost exactly like the old magnetic Wiegand Wire swipe-cards, which align the wires high or low so they go past different read heads. I've always thought

It's almost exactly like the old magnetic Wiegand Wire swipe-cards, which align the wires high or low so they go past different read heads. I've always thought of Wiegand as a 1-d barcode because the displaced wires are just a way of achieving "contrast" and clocking, basically. But I could see the argument breaking down into semantics.