[formerly_proven]

> And many people know that specific colors are really just wavelengths in the electromagnetic spectrum.

Colors that can be stimulated using a single wavelength are spectral colors, which are only a small subset of perceptible colors. In the CIE xy model, spectral colors are on the curved boundary, while the straight boundary is the line of purples - impossible colors.

Edit: And because CIE XYZ is used as a sort of universal connecting and definition space, all our color spaces are defined in terms of it. But this leads to a the-map-is-not-the-territory fallacy: CIE XYZ was based on just a handful of observations and generously extrapolating. CIE XYZ does not define the set of visible colors. It's a map of colors.

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This post is about conversion from the video's color space to a rendering color space, and the problems with that. Another fun question is whether that rendering color space is actually the display device's color space, or nah. While browser do output color management (i.e. they use the color profile of the output device and convert all their output to the ad-hoc color space that represents), I don't think they do that for video actually. In fact, there are virtually no video players supporting color management on the output side of things.

[galad87]

Apple's AVFoundation is color managed: https://developer.apple.com/library/archive/technotes/tn2227...

I would hope that similar frameworks on Windows and Linux distributions are too.

[cratermoon]

There are for Windows, too. I don't know about Linux. The catch is that for really exact color work, you have to calibrate and tune for your computer/OS/video card/monitor combination, and check the calibration against a known standard periodically. It's a bit of pain.

[formerly_proven]

Well this is pretty easy to test. Use a wide-gamut display and use the display's profile. Yeah, sure that might not be accurate, but it tells color-managed applications what the display color space roughly is. Then play a video. Observe whether the colors are drastically different from no profile and sRGB emulation in the display. In a color managed system, both of these should look roughly the same (and they do).

My result: Yes, they are. Totally different. Crab people everywhere. Player does not matter.