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Comment by Osmium | Hacker News Reader

> 2) The "TrueDepth" data is not really all that granular. It seems similar to the depth map you get from the rear-facing cameras on the "plus" sized models. Here's what the sensor data spits out: https://twitter.com/braddwyer/status/930682879977361408

As @braddwyer himself notes, you can probably get a much better mesh integrating over time. It depends how long it takes to capture a single frame, but I imagine that's not long, so getting an order of magnitude improvement is probably quite easy.

> 4) The scary part, which is vast dystopian databases of facial fingerprints is already being done with normal photographs. The depth data is not needed.

And yes ... after all, humans are quite capable of identifying people with high accuracy from 2D photographs. Depth maps are not required for there to be serious privacy issues with such databases.

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@braddwyer is me :)

It gives you about 15 fps of depth data

Haha, cool! Hi :)

Given the small size of the laser projector, I imagine natural movement from the phone being hand-held would result in significant displacement of the projected dots over a 1s interval? Have you tried integrating the 15 frames to see what it looks like?

I haven't yet.

We submitted a game about 3 weeks ago using front-facing ARKit as its core game mechanic and it hasn't been approved by Apple yet.

I'm waiting to see if they're going to allow us to use the new technology in novel ways or not before I invest a lot more time in it.

Could you stabilize this before integrating? Using feature points and matching them up, perhaps?

I imagine something like that would be necessary. The techniques would probably be ones related to those used in SLAM [1].

[1] https://en.wikipedia.org/wiki/Simultaneous_localization_and_...

Getting minute, subpixel movements can ironically give you MORE resolution if you process it over time, though you'd probably need some sort of "anchor" points

That doesn’t seem ironic to me.

I think the irony being implied is that normally when you're shooting video and your camera is jittering, you're effectively losing resolution compared to a static camera because of motion blur, whereas this depth mapping benefits from minute movements. Though looking at individual frames of video is different than combining them into a single sharper image, I get the counterintuitive feeling they were driving at.

> And yes ... after all, humans are quite capable of identifying people with high accuracy from 2D photographs. Depth maps are not required for there to be serious privacy issues with such databases.

Yes and no. We’re mostly good at that (with exceptions — I have to see someone a lot before I remember their face), but we evolved for small groups and therere are now enough people that doppelgänger is a profession.

On the other hand, databases are still a problem because collections of timestamped photos can reveal far too much about us once an identity is properly confirmed.

> And yes ... after all, humans are quite capable of identifying people with high accuracy from 2D photographs. Depth maps are not required for there to be serious privacy issues with such databases.

Which would be true if they were actually storing this on the cloud in a form they could access. As far as we know, they are not. That's the point of the "Secure Enclave".

The Secure Enclave doesn’t do much good if you are providing the face map to any developer that wants it.

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