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Show HN: What's my JND? – a colour guessing game

keithcirkel.co.uk

41–50 of 65 posts

Re: Show HN: What's my JND? – a colour guessing game

#41

This is fun! I just played once and got 0.0016, which it says is "absurdly below the theoretical limit"... Okay, tried again and got 0.0034 which is still says is beyond the human limit! I'll have to give this to my mum because we often argue about colours and I suspect she might be a tetrachromat. Both tests on a Pixel 10 btw

Tetrachromacy wouldn't affect a test taken through a phone screen.

Re: Show HN: What's my JND? – a colour guessing game

#46
There was a similar web-game back in the day but for tones. You had to identify which one was higher or lower. Also gave a statistical comparison at the end. Near the end the difference was a couple hertz or something, so next to impossible as well.

I can't find it now. Is anyone else aware of what I'm talking about?

Re: Show HN: What's my JND? – a colour guessing game

#47
post #46

There was a similar web-game back in the day but for tones. You had to identify which one was higher or lower. Also gave a statistical comparison at the end. Near the end the difference was a couple hertz or something, so next to impossible as well. I can't find it now. Is anyone else aware of what I'm talking about?

was it this? https://www.themusiclab.org/quizzes/td

Re: Show HN: What's my JND? – a colour guessing game

#48

Earlier quoted context omitted.

It's worse. The code contains a function that, given the target ΔE, generates two colors in floating-point Oklab representation, separated by that distance. But there is no check whether the two generated colors end up rounding to exactly the same one on 8-bit displays. So, I was asked to find a boundary (while the claim was that there were two distinct colors 0.0013 ΔE apart) between RGB(80, 83, 152) and RGB(80, 83,…

I will get around to fixing this. An oversight. Apologies.

Another issue is that it discards the color pair if the generated coordinates fall outside 100% sRGB. The problem here is that many low-end laptop displays cover significantly less than 100% sRGB, but come with the correct primaries in the EDID, thus causing browsers to display colors correctly if they can and clip colors if they can't. Colors too close to the sRGB boundary will be clipped in your game - different colors generated, different colors when converted to sRGB, same color on the screen because it is out of the screen gamut. Maybe it makes sense to avoid colors with more than 60% saturation?
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