Talk:Color appearance model

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IPT non-constant lines of hue[edit]

The IPT section mentions "the issue of non-constant lines of hue" but no where up the page are lines of hue explained, or even mentioned. Pnorman (talk) 01:25, 22 March 2018 (UTC)[reply]

What I think the editor meant is that some of the models have the property that changing the physical brightness of a stimulus might result in a hue change, rather than just a lightness change.
The developers of IPT argue that theoretically, according to them anyway, that shouldn't happen. In the IPT model, if you multiply the XYZ vector by a constant K, this first commutes with the HPE matrix, then can be pulled out of the power function and finally commutes with the IPT matrix, resulting in a final constant scaling factor of K·⁴³ in the IPT vector. So within their theoretical framework it preserves hue.
The thing is, there are good reasons to think the physical brightness does affect perceived hue. So I doubt the validity of the raison d'être of IPT and it contributes nothing else to the field. In particular, it doesn't even attempt to model human colour vision. I'd argue that even the most recent models are only a first step, but still it's something and that cannot be said for IPT. — Preceding unsigned comment added by 92.67.227.181 (talk) 16:19, 2 July 2022 (UTC)[reply]

CAM20u[edit]

Any info on CAM20u? — Preceding unsigned comment added by 77.61.180.106 (talk) 23:32, 7 March 2021 (UTC)[reply]

CIECAM16[edit]

So the news kind of passed me by, but you guys apparently didn't notice it either: CAM16 is an official CIE standard now: CIE 248:2022. — Preceding unsigned comment added by 92.67.227.181 (talk) 00:57, 4 June 2022 (UTC)[reply]

Also, ‘various fixes and improvements’ is code for ‘I haven't actually read it’. And I know you haven't read it, because if you had this would have jumped out at you like a flashing neon sign: it uses one colour mapping matrix rather than two, eliminating not just an enormous numerical problem with the previous models, but also the most important outstanding point of psychophysical implausibility of the same. — Preceding unsigned comment added by 92.67.227.181 (talk) 11:06, 6 June 2022 (UTC)[reply]

Color appearance[edit]

"In 1931, using psychophysical measurements, the International Commission on Illumination (CIE) created the XYZ color space, which successfully models human color vision on this basic sensory level." This is very misleading: The LMS color space attempts to model the human sensory system. The 1931 XYZ color space models how humans perceive colors, while the cone functions were still unknown. 109.199.166.7 (talk) 13:17, 5 September 2022 (UTC)[reply]

? There's nothing misleading here. As you say yourself, The LMS color space attempts to model the human sensory system – which is not of interest here. Color Appearance is about how humans perceive colors, and this is – again, as you say – what the XYZ color space tries to model. Uli Zappe (talk) 16:23, 10 April 2023 (UTC)[reply]

Requested move 10 April 2023[edit]

The following is a closed discussion of a requested move. Please do not modify it. Subsequent comments should be made in a new section on the talk page. Editors desiring to contest the closing decision should consider a move review after discussing it on the closer's talk page. No further edits should be made to this discussion.

The result of the move request was: not moved. (closed by non-admin page mover) MaterialWorks (contribs) 16:18, 17 April 2023 (UTC)[reply]


Color appearance modelColor appearance – "Models" is just a smaller section of the article. fgnievinski (talk) 15:11, 10 April 2023 (UTC)[reply]

This is not true. In fact, the "Models" section is longer (6800 characters) than the rest of the sections combined (5200 characters).
This mirrors the actual focus of the article, which is Color Appearance Models and not Color Appearance. Color Appearance Models are an important part of color management, whereas I'm not aware of a similar thorough discussion of Color Appearance as such in any field. Most if not all research listed in section 3 (Color appearance phenomena) has been done in connection with Color Appearance Models. Sections 1-3 only serve as an introduction to section 4.
As the originator of this article, who wrote it as part of the series of articles about color management, I strongly oppose the renaming. Uli Zappe (talk) 16:17, 10 April 2023 (UTC)[reply]
No, this makes no sense. These are two different subjects. More generally, @Fgnievinski, can you please stop trying to re-organize random articles that you aren’t otherwise involved in researching/writing/editing? It’s an annoying distraction for other editors and has no real benefit. ––jacobolus (t) 18:32, 10 April 2023 (UTC)[reply]
@Uli Zappe: thank you for the clarification. As you said "Sections 1-3 only serve as an introduction to section 4", I've made that intention more explicit by creating an umbrella Background section for sections 1-3. That way, it's easier for more knowledgeable readers to skip the introductory material and access the main topic of this article. fgnievinski (talk) 14:47, 11 April 2023 (UTC)[reply]
I agree with Uli Zappe and jacobolus. North8000 (talk) 18:08, 11 April 2023 (UTC)[reply]
The discussion above is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.