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A comment on Elligator: Elliptic-curve points indistinguishable from uniform random strings. Parent comment

Re:Elligator: Elliptic-curve points indistinguishable from u... by ZenMikey on Thursday July 18, 2024 @01:16PM (#40997743)
I was always fascinated by stuff like LSB stenography where you hide a message (or another image) in the least significant bits of an image. Not visible to the human eye, mathematically should look like thermal noise in the image at most.
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Re:Elligator: Elliptic-curve points indistinguishable from u... by Retr0id on Thursday July 18, 2024 @01:42PM (#40998019)
Image sensor noise is not a uniform distribution (I believe it's typically modeled as a Gaussian distribution, but even that's an approximation).

Thus, it is mathematically/statistically distinguishable.

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Re:Elligator: Elliptic-curve points indistinguishable from u... by NavinF on Thursday July 18, 2024 @05:18PM (#40999852)
The LSB of samples from a gaussian distribution is uniformly distributed: 50/50 chance of 0/1

(Assuming you have enough bits per sample which image sensors provide IRL)

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Re:Elligator: Elliptic-curve points indistinguishable from u... by Retr0id on Thursday July 18, 2024 @05:26PM (#40999922)
Only in theory. In practice, they're correlated with the other bits and adjacent pixels.
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Re:Elligator: Elliptic-curve points indistinguishable from u... by NavinF on Friday July 19, 2024 @04:15AM (#41003326)
How correlated? I spent 2 minutes trying and failing to get chatGPT to generate code that downloads an image dataset and runs diehard on the LSBs. I'd expect the LSBs to pass the randomness test.
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