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Re:JPEG Compression by Paulo75 on Wednesday March 18, 2026 @08:47AM (#47425101)
The part about green getting 58.7% weight in the luminance calculation is one of those details that seems arbitrary until you realize it's literally modeled on the density of cone cells in the human retina. The whole algorithm is basically a map of what human eyes can't see.
Re:JPEG Compression by fuoqi on Wednesday March 18, 2026 @09:03AM (#47425289)
>it's literally modeled on the density of cone cells in the human retina

It's related to it, but not "literally modeled" on it. This number is from experiments where people are asked to equalize perceived brightness of two lights with different colors. The results are than averaged out and interpolated using polynomials to create a color model [0].

[0]: https://en.wikipedia.org/wiki/Color_model