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Comment by dabinat

17 hours ago

It would be great if they could use the LiDAR scanner to sign a depth map of the scene in front of the camera. It would show if you photographed a flat image.

The sensor already uses phase detection autofocus. You can create a depth map out of it. iPhone X used its dual cameras and that phase data for depth maps.

The 'ol "analog hole". Never been able to patch that gap.

  • Yes, if your adversary can generate a high-fidelity 3D moving replica of a scene, they can deceive you that it’s real. But can they really?

If that became popular, the AIs would learn how to generate a realistic depth map along with any generated image.

  • How would that work? I thought the premise here is that you can fool the apple camera by taking a (very carefully aligned) picture of a still image (printed out).

    A depth map from the apple camera (again, signed) would show that the entire image had the same distance from the camera.

    • You're right. I think my comment above doesn't make sense - it wouldn't help in this case.

  • The photos are cryptographically signed in the apple image pipeline so it's not as simple as just AI generating something. That said, I can't see how this is any different to all the other times we have embedded crypto keys in consumer hardware where eventually someone finds a way to extract the key and the whole thing is busted open.

    • Nobody has breached the Secure Enclave, not sure it’s doable without investing millions in direct circuit manipulation. Seems good enough

  • > generate a realistic depth map along with any generated image.

    There are already pretty good depth map generation algorithms (for a decade or so) which works on 2D images.

    Generate the image, feed it to a depth map generator, viola.

    However, you can't get it signed by the sensor itself. That'd be hard.