Re: I don't know...
Understanding depth by using one eye is a really difficult problem. However, using two eyes to measure depth nearby is relatively easy, and AI labs have been doing it for a long time.
When driving, humans do not use stereo vision, distances are too great. But a computer can have two or more cameras spaced well apart. The hard part is to recognize that an edge seen from the two cameras are actually from the same object. Then a simple bit of trig gives you the distance.
I am surprised this approach is not used. But I suspect that the car manufacturers are more auto engineers hacking AI rather than AI researchers.