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0 pointsebg136y ago0 comments

> So the main problem is not just building the 3d models

That's not relevant when discussing which technology to use to build the 3d models. Everything you said is accurate until the last few sentences. Lidar provide the same information (line of sight depth) as stereo cameras, just in a different way. The person you're responding to is talking about depth from stereo, not cognition.

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kajecounterhack6y ago

> Lidar provide the same information (line of sight depth) as stereo cameras, just in a different way.

This is incorrect, the amount of parallax you need to get the same kind of accurate depth using camera is infeasible. Velodynes other common lidar now gets you points accurate at 150m+. Cameras can't do that, and if you use nets to guess you'll still make mistakes.

> The person you're responding to is talking about depth from stereo, not cognition.

You miss the point; saying human 3D reconstruction works because of sensors without world context is naive. The response was trying to capture that; human perception systems utilize context / background knowledge extensively.

ebg13OP6y ago

> the amount of parallax you need to get the same kind of accurate depth using camera is infeasible. Velodynes other common lidar now gets you points accurate at 150m+

I meant they both just provide line of sight depth.

The point being made by the first comment is that human eyeballs placed one inch apart are currently the gold standard for the actual looking part. So the right set of cameras is by definition sufficient for the looking part of driving. The cameras just have to replace eyes well enough. The brain replacement is farther down the chain.

kajecounterhack6y ago

From the OP:

> humans can build near perfect 3D representations of the world with 2D images stitched together with the parallax neural nets in our brain

This is a statement about cognition. And the response addresses this.

Your response:

> The person you're responding to is talking about depth from stereo, not cognition.

I think this is the disconnect. The person _is_ talking about cognition. OP makes a claim about how humans see, connected to how the human brain works. Response explains why camera-based image recognition right now is a lot worse than your eyes (a big piece of the answer is your brain).

> The cameras just have to replace eye well enough

So yes this is nice in theory. But I also get the sense most people don't realize just how large the chasm is today between cameras and human eyes. They don't "just provide line of sight depth." Dynamic range, field of view, reliability even under conditions like high heat -- there are many other dimensions where they just aren't analogous yet.

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kajecounterhack6y ago

> Lidar provide the same information (line of sight depth) as stereo cameras, just in a different way.

> The person you're responding to is talking about depth from stereo, not cognition.

ebg13OP6y ago

> the amount of parallax you need to get the same kind of accurate depth using camera is infeasible. Velodynes other common lidar now gets you points accurate at 150m+

I meant they both just provide line of sight depth.

kajecounterhack6y ago

From the OP:

> humans can build near perfect 3D representations of the world with 2D images stitched together with the parallax neural nets in our brain

This is a statement about cognition. And the response addresses this.

Your response:

> The person you're responding to is talking about depth from stereo, not cognition.

> The cameras just have to replace eye well enough

j / k navigate · click thread line to collapse