6 ms·

How is entropy defined in this context? Clearly there is human-derived input in the system (otherwise... What's the point just crop randomly)

• TheGallopedHigh 5y ago
  Randomness in pixel values
• jedberg 5y ago
  Here is the code: https://github.com/reddit-archive/reddit/blob/753b17407e9a9dca09558526805922de24133d53/r2/r2/lib/media.py#L92 https://github.com/reddit-archive/reddit/blob/753b17407e9a9d... But in short, it's a histogram of the values of the pixels.
  • bavell 5y ago
    "Entropy" in this context also left me wondering. Perhaps "variance" or "deviation from the mean"? Thanks for the insights!
    • MauranKilom 5y ago
      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.
  • andbberger 5y ago
    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.