The process looks like magic. Color-mixed items go in, and single-color items come out, on a line going so fast that no human can see what's happening. It's amazing to see computer vision systems that fast.
These machines work by putting the items on a conveyor belt, then dropping them on a much faster conveyor to spread them out. The fast conveyor goes past cameras, and at the end, launches the items into free flight for a few inches. While in flight, computer-controlled air jets knock out the rejects.