Widely available image recognition software can tell the difference between birds, planes, baseballs and missiles already.

Depends. It would be a non-trivial problem when dealing with only 1 - a few pixels, which is likely.

	▲	ceejayoz 9 hours ago \| parent [-]
		It's not that hard. Planes and birds act pretty differently, even when pixel sized. Doubly so when you've multiple cameras networked all over the area.