[mgoetzke]

considering cameras can create reliable enough distance measurements AND also handle all the color reception needed for legally driving roads it was always a ridiculous idea by a certain set of people that lidar is necessary.

[tsimionescu]

No, cameras cannot create reliable distance measurements in real-world conditions. Parallax is not a great way to measure distance for fast, unpredictably moving objects (such as cars on the road). And dirt or misalignment can significantly reduce accuracy compared to lab conditions.

Note that humans do not rely strictly on our eyes as cameras to measure distances. There is a huge amount of inference about the world based on our internal world models that goes into vision. For example, if you put is in a false-perspective or otherwise highly artifical environment, our visual acuity goes down significantly; conversely, people with a single eye (so no parallax-based measurement ability) still have quite decent depth perception compared to what you'd naively expect. Not to mention, our eyes are kept very clean, and maintain their alignment to a very high degree of precision.

[s08148692]

I don't think they meant literally cameras only can create reliable distance measures. At the risk of putting words in their mouth, I would guess they meant "cameras as the only input to a distance model". the "model" doing all the heavy lifting, covering the points that you quite rightly point out are needed

Several companies, most notably Tesla, have done this well enough to drive in all manner of traffic. I'm not going to comment about if lidar is strictly needed or not to achieve better-than-human safety, that's yet to be proven one way or another by anyone. The point is that cameras + local inference can do a pretty good job at distance estimation

[numpad0]

Stereo cameras are useless against repeating patterns. They easily match neighboring copies. And there are lots of repeating or repeating-like patterns that computers aren't smart enough to handle.

You can solve this by adding an emitter next to the camera that does something useful, be it just beaconing lights or noise patterns or phase synced laser pulses. And those "active cameras" are what everyone call LIDARs.

[ImPostingOnHN]

'cameras can see in color, therefore lidar is unnecessary for self driving' is unconvincing

[throwa356262]

There are tons of evidence showing that cameras are alone are not safe enough and even Tesla has realized that removing lidar to save cost was a mistake.

[xpe]

> ridiculous idea by a certain set of people that lidar is necessary.

"Necessary"? Seems like a straw man, don't you think? I strive to argue against the strongest reasonable claim someone is making.

Lots of reasonable people suggest LIDAR is helpful to fill in gaps when vision is compromised, degraded, or less capable.

People running businesses, of course, will make economic trade-offs. That's fine. But don't confuse, say, Elon's economic tradeoff with the full explanation of reality which must include an awareness that different sensors have different strengths in different contexts.

So, when one thinks about what sensor mix is best for a given application, one would be wise to ask (and answer) such questions as:

- What is the quality bar?

- What sensors are available?

- Wow well do various combinations of sensors work across the range of conditions that matter for the quality bar?

- WRT "quality bar": who gets to decide "what matters"? The company making the cars? The people that drive them? regulators that care about public safety. The answer: it is a complex combination.

It is time to dismiss any claim (or implication) that "technology good, regulation bad". That might be the dumbest excuse for a philosophy I've ever heard. It is the modern-day analogue of "Brawndo's got what plants crave." Smart people won't make this argument outright, but unfortunately, their claims sometimes reduce to this level of absurdity. Neither innovation nor regulation are inherently good nor bad. There are deeper principles in play.

Yes, some individuals would use their self-proclaimed freedom to e.g. drive without seatbelts at 100 mph at night with headlights off. An extreme example, but it is the logical extension of pure individualism run amok. Regulators and anyone who cares about public safety will draw a line somewhere and say "No. Individual stupidity has a limit." Even those same people would eventually come to their senses after they kill someone, but by then it is too late.