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A comment on Sharing learnings about our image cropping algorithm. Parent comment

Re:Sharing learnings about our image cropping algorithm by opsy2 on Wednesday May 19, 2021 @04:32PM (#27214106)
How is entropy defined in this context?

Clearly there is human-derived input in the system (otherwise... What's the point just crop randomly)

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Re:Sharing learnings about our image cropping algorithm by jedberg on Wednesday May 19, 2021 @04:51PM (#27214321)
Here is the code:

https://github.com/reddit-archive/reddit/blob/753b17407e9a9d...

But in short, it's a histogram of the values of the pixels.

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Re:Sharing learnings about our image cropping algorithm by andbberger on Wednesday May 19, 2021 @07:25PM (#27215707)
Which is not really image entropy at all, as it totally neglects spatial structure. You could sort an image and get the same entropy using the histogram approach.
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Re:Sharing learnings about our image cropping algorithm by bavell on Wednesday May 19, 2021 @06:47PM (#27215494)
"Entropy" in this context also left me wondering. Perhaps "variance" or "deviation from the mean"?

Thanks for the insights!

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Re:Sharing learnings about our image cropping algorithm by MauranKilom on Wednesday May 19, 2021 @07:29PM (#27215731)
Entropy usually boils down to "sum p * log(p) for all p (and possibly normalize)", assuming you have discrete probabilities p. It is not related to variance or mean.
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Re:Sharing learnings about our image cropping algorithm by TheGallopedHigh on Wednesday May 19, 2021 @04:47PM (#27214264)
Randomness in pixel values
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