Re: [css-color] wider/deeper colors

> On 11 Feb 2016, at 12:06 PM, Dean Jackson <dino@apple.com> wrote:
> 
> 
>> On 11 Feb 2016, at 11:40 AM, Tab Atkins Jr. <jackalmage@gmail.com> wrote:
>> 
>> I agree with your reasoning; my only concern is what to name the
>> "better" value that'll allow us to discriminate between "new normal"
>> and "even more betterer" in ten years, when devices with deeper/wider
>> colors than 3*8 are commonplace.
> 
> Yeah. I haven't come up with anything even remotely good for names here.
> 
> We could ignore it slightly and use "level1", "level2", etc. Or use years
> like "2016", "2019" to mean the type of display you'd expect to get for
> a purchase of x% of median wage in that year. It's the new arm length!
> It might require predicting the future :)
> 
> I did say I haven't come up with anything good.

I'm now flip-flopping back to something that uses existing, well-known profiles, which wasn't exactly what we originally proposed, but I think they make more sense.

Here is the text:

>>> 1. Add a new media query that is able to detect the "depth" of the display. I put that word in quotes because I think the current "color" query isn't sufficient and we need a term to better describe what we're trying to detect. The "color" query examines the number of bits per channel, but that doesn't allow you to ask if the display can show things outside sRGB. Instead we suggest there should be range-type query that allows you to detect "normal" (typical displays from today, in the sRGB range or about), "extended" (wider gamut displays, in the DCI P3 range or about) and "super-awesome-needs-a-better-name" displays (very wide gamut displays, in the Rec. 2020 range or about). I believe this might be the first media query that has named values but works as a range. We don't have good suggestions for the name of this query.

(#include the color expert equivalent of "I am not a lawyer")

I suggest the name of the query be "color-support". It implies that the software and hardware do their best effort to represent colors of this range.

I think we might be able to get away with three values.

color-support: sRGB | P3 | Rec2020

or 

color-support: sRGB-equivalent | P3-equivalent | Rec2020-equivalent

… because there are many different forms of P3 (e.g. Photoshop allows you to choose from 8!) and not all displays might be the same. For the Apple iMacs, we suggest people use the "Display P3" profile when authoring artwork. As far as I can tell, these three values would cover the two most well-known and supported important steps up from what is common today. And we can add new steps if necessary.

I guess the main point is that we can't really be specific here, because there are lots of choices, and you can find many articles that describe how existing Ultra-HDTVs say they support Rec 2020 but at best cover 90% of the gamut. What we're trying to achieve is a way to allow a developer to at least try to provide images that are the most accurate for the user's configuration (e.g. they want to send a P3 image if possible, but otherwise would be better off sending an sRGB image rather than risking clamping).

I'm planning to send a pull request with this proposal soon (if that's how it is done in CSS).

Dean

Received on Saturday, 13 February 2016 03:13:30 UTC