For a minute I thought this was an April Fools joke, but it looks like an awesome idea. Wonder in what other ways this would be do-able. Antlers I imagine would need much higher resolution images from a fixed vantage point to detect similarity...
Nice - could also have a Tartan scanner (to identify Scottish clans) or a tree trunk scanner to age a tree, or a wood grain scanner to identify different types of wood...
Idea: create a startup that sews unique barcode tshirts so that this technique can be used to identify anything.