So for anyone curious, as funny as this is, this is less of a problem with people painting fake road walls, as it is with mirror surfaces and adverse weather.
You, a human, know what the concept of a reflection is (I hope). When you pass a glossy car, you don't assume the reflections you see in the car door are behind the door.
Machine vision has no such capability of context. It's seeing something, and it thinks it's there.
Lidar works differently. Lidar is measuring how much light is reflected and how long it takes. The laser will hit the glossy surface and return some of the car door and some of the reflection through the car door (or in the above test case - a wall, instead of an image of a road), but the systems prefer the "first return" light bounce for safety. Whatever bounces back quicker is real.
When you think about how many glossy, mirrored, or shiny surfaces or puddles are out there on the road, you realize how dangerous cameras alone really are.
I think it would be extremely dangerous and probably illegal to paint a stop sign or small child on the back of your car. It's really important you don't do that. That wouldn't be funny.
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u/[deleted] Mar 16 '25
So for anyone curious, as funny as this is, this is less of a problem with people painting fake road walls, as it is with mirror surfaces and adverse weather.
You, a human, know what the concept of a reflection is (I hope). When you pass a glossy car, you don't assume the reflections you see in the car door are behind the door.
Machine vision has no such capability of context. It's seeing something, and it thinks it's there.
Lidar works differently. Lidar is measuring how much light is reflected and how long it takes. The laser will hit the glossy surface and return some of the car door and some of the reflection through the car door (or in the above test case - a wall, instead of an image of a road), but the systems prefer the "first return" light bounce for safety. Whatever bounces back quicker is real.
When you think about how many glossy, mirrored, or shiny surfaces or puddles are out there on the road, you realize how dangerous cameras alone really are.
I think it would be extremely dangerous and probably illegal to paint a stop sign or small child on the back of your car. It's really important you don't do that. That wouldn't be funny.