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Comment by kllrnohj | Hacker News Reader

graphic designers don't really see any of this, either. It's going to be photo junkies or people working on image processing systems (either building them or using them) that have to deal with this.

But for the most part this shouldn't really matter much. A huge amount of things these days are properly color managed, so as long as the thing that wrote the profile actually, you know, wrote what it actually wanted then it'll display just fine regardless of how many different "sRGB" profiles there are floating around. We're largely past the days of just hoping that the image and the display happen to agree on roughly the same colors.

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The problem, as I described in another comment, is that the average programmer doesn't know enough about colour spaces, and sometimes must choose a colour profile while not knowing nor understanding what they actually want. They can figure out that an "sRGB" profile is probably what they want, but then there should not be such a plethora of different versions of that, as choosing between them is impossible for anyone not in the know.

This is more like the stuff Linux users had to endure in the bad old days of setting up drivers. Concerns of twenty years ago. I remember the days people compared their colorimeters and profiled their own monitors. I'm too old for this.

> I remember the days people compared their colorimeters and profiled their own monitors.

That would be calibration and it's still necessary if you want color accuracy. That's about ensuring that what your monitor thinks it's displaying and what it's actually physically emitting are the same. The main thing that's changed here is that factory calibration has become a lot more common and is often more than good enough for anything short of serious professional work. Even for things that aren't professional displays. Like most flagship or even midrange smartphones are factory calibrated with dE values that would make reference monitors from 20 years ago blush. Right up until the OEM shoves a shitty color curve on it intentionally to make it "pop" or be more "vibrant" (Samsung calls this "Vivid", Pixel calls it "Adaptive", etc.. - but they at least usually have a "natural" option that gets you back to the properly calibrated display)

> That would be calibration and it's still necessary if you want color accuracy.

Your correction is backwards. Profiling + colour-managed apps gets you accurate colours regardless of source colourspace. Calibration doesn’t, and is not strictly needed either.

https://discuss.pixls.us/t/rip-displaycal/21775/130

No, my correction is correct. Colorimeters are physical measurement devices to adjust the display so that it reports an accurate color profile in the first place for which to color manage to. It's required for the monitor itself to be able to display accurate colors at all.

> Colorimeters are physical measurement devices to adjust the display so that it reports an accurate color profile in the first place for which to color manage to.

No. You can profile an uncalibrated (unadjusted) display and the profile will be correct. There is zero inherent requirement to adjust the display, or for the display itself to report a profile.

> It's required for the monitor itself to be able to display accurate colors at all.

Also no. Once you have profiled the uncalibrated display, you can accurately display colours within its gamut by converting to the profile.

> We're largely past the days of just hoping that the image and the display happen to agree on roughly the same colors.

<Heath Ledger Joker>Ah haa ha ha haaaa!</Heath Ledger Joker>

We're nowhere near past that point, we haven't even begun to approach that point. That point is something I would like to reach before I die, but since that's maybe just a couple of decades away, it's not looking likely.

In general, Windows and Linux does not color manage, or so badly that it is counter-productive.

Most sub-$500 monitors do not report their native gamut! By default, operating systems assume monitors are sRGB (they're typically not), and send un-calibrated 8-bit RGB as-is.

On Windows and MacOS, enabling HDR mode typically sets the correct gamut, etc... and mostly makes things "just work", but that's at the OS level only.

Almost all applications map wide-gamut images to sRGB even on HDR monitors or simply re-interpret the RGB values as-if they're sRGB without even bothering to color space convert.

Firefox has color management off by default. Microsoft Edge defaults to "crush to sRGB". Apps with embedded web view controls are "who knows?"

In general, widge-gamut, 10 bits per channel, and HDR support are all a total shit show. I'm perpetually surprised if any of it works!

As a random example, my Nikon Z8 DSLR can natively record HDR 10 bit wide gamut HEIF files in-body. Windows can't display those at all. MacOS and iPhones can... sometimes... but then the viewer apps will often "get confused" and the brightness will jump around randomly and non-deterministically as you switch between thumbnail and full screen views. You can't forward such an image to anyone via iMessage, they'll get gibberish on their end, and SMS/MMS is hopeless.

Meanwhile, YouTube HDR generally "just works" on most devices, so I've started sending people my still image photography by converting them to a HDR 4K slideshow in DaVinci Resolve and giving them a YouTube link.

It's sad and pathetic that Meta set $80 billion on fire for the Metaverse and the rest of the industry found a decent chunk of a trillion dollars under the couch cushions to throw at AI slop, but nobody can "afford" to have one or two engineers fix their imaging pipeline.

Upload a HDR or wide-gamut image to Faceobook successfully and then tell me it "just works".

Or send one in an email.

Or do anything with it other than view it on your own device.

HDR has problems that aren't the fault of missing color management. Notably, the fact that HDR of the HLG & PQ variety (so HDR10) do not have specified behavior. The specs are wrong in that they basically just don't exist for half the problem. Which also means most content is badly authored, too, almost certainly including your fancy pants Nikon. This is why gainmap images almost immediately dominated the mobile phone capture space, they are actually properly defined. So both viewers and creators know what they're actually intended to do.

The rest of your rant seems mostly anchored around the fact that most things still produce sRGB, which is true, but they still typically map inputs into sRGB appropriately (that is, they get clipped). Which still is being properly color managed.

All of my rant applies identically to 10 bpc images and wide gamut (non-sRGB) for exactly the same underlying reasons. They all have the same fix: frame buffers must be 16 bpc and input images must be color managed.

HDR has one extra minor issue on top, which is that there needs to be an output mapping to the display max brightness capabilities but this isn’t that different to what’s needed to correctly tone map wide gamut to arbitrary displays.

Also: if the spec is so “wrong” why does YouTube HDR just work? Also… Apple TV, NetFlix, etc… on practically all devices?

They got it right!

There is no fundamental color management difference between moving and still images.

If anything, moving images are harder!

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