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Comment by bee_rider | Hacker News Reader

The iPhone definitely does some extra processing on text. I’m 99% sure that it recognizes letters and fills in “creatively.” I noticed this while taking some photos of text in low-light. Could barely see it with my eyeballs but the phone worked it out.

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To be fair, sensors have the luxury of time that our eyes don’t have. See astrophotography for an example of “could barely see it but the sensor worked it out.”

Sensors may have the time, but our hands do not; they are unsteady in subtle ways.

When making photos in low light, I always try to lean my phone against something (a bench, a lamppost, a tree, a building) to let the longer exposure be sharper.

as long as there is anything to key onto it's possible to remove the shake algorithmically

> as long as there is anything to key onto it's possible to remove the shake algorithmically

Why the requirement? The phone already has accelerometers, doesn't it?

In any case, less hake should still be easier for the phone to deal with. Those algorithms aren't flawless.

There's no way that the accelerators/gyrocscope would be accurate enough to remove the shake. According to google, the iphone gyroscope is accurate to within about 0.5 degrees, roughly two orders of magnitude away from being pixel accurate in a 1x zoom image.

Thanks for providing the numbers!

Maybe, but it looks like a problem of unscrambling an egg. The true image has been smeared over the sensor, superimposed on itself a bit. Maybe there is a good enough solution for the problem of finding the true image, but I can't imagine it to be computationally inexpensive.

This.

Even when you stabilize the footage afterwards (digitally, not by stabilizing the sensor), there will be motion blur due to the lower shutter speed.

I don’t get your point. Surely you’ve seen that the iPhone is perfectly able to do 10s handheld exposures. Something in the algorithm can unscramble those eggs because there’s no way it should be able to capture clear pictures with nearly no light.

It doesn't do that. Text just has a lot of edges so there's a lot of opportunities for image fusion to register them.

Apple power adapters actually have a bunch of text on them printed in unreadable light gray; you can try shooting them and while they're a bit clearer than plain old eyesight, they're still pretty unreadable.

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