Comment by wolrah
14 hours ago
> Always worth noting, human depth perception is not just based on stereoscopic vision, but also with focal distance
Also subtle head and eye movements, which is something a lot of people like to ignore when discussing camera-based autonomy. Your eyes are always moving around which changes the perspective and gives a much better view of depth as we observe parallax effects. If you need a better view in a given direction you can turn or move your head. Fixed cameras mounted to a car's windshield can't do either of those things, so you need many more of them at higher resolutions to even come close to the amount of data the human eye can gather.
Easiest example I always give of this is pulling out of the alley behind my house: there is a large bush that occludes my view left to oncoming traffic, badly. I do what every human does:
1. Crane my neck forward, see if I can see around it.
2. Inch forward a bit more, keep craning my neck.
3. Recognize, no, I'm still occluded.
4. Count on the heuristic analysis of the light filtering through the bush and determine if the change in light is likely movement associated with an oncoming car.
My Tesla's perpendicular camera is... mounted behind my head on the B-pillar... fixed... and sure as hell can't read the tea leaves, so to speak, to determine if that slight shadow change increases the likelihood that a car is about to hit us.
I honestly don't trust it to pull out of the alley. I don't know how I can. I'd basically have to be nose-into-right-lane for it to be far enough ahead to see conclusively.
Waymo can beam the LIDAR above and around the bush, owing to its height and the distance it can receive from, and its camera coverage to the perpendicular is far better. Vision only misses so many weird edge cases, and I hate that Elon just keeps saying "well, humans have only TWO cameras and THEY drive fine every day! h'yuck!"