Re: [css-color] wider/deeper colors

On 22.03.2016 08:45, Florian Rivoal wrote:
> 
>> On Mar 22, 2016, at 11:34, Rik Cabanier <cabanier@gmail.com> wrote:
>>
>> It could be a new CSS property, for instance: compositing-space: "p3"/"sRGB"/"uncalibrated"/url(..)
> 
> Shouldn't that be "compositing space: sRGB | output | CIELab" ?
> 
> * sRGB: legacy "make everything dull" mode
> 
> * CIELab: because if you're compositing things coming form various color spaces or wide gamut color spaces, this is how you get the least color distortion. 
> 
> Say your sources are in a gamut wider than the output gamut, and you have semi-transparent very saturated red on top of very saturated blue. If you composite in CIELab, then convert to the output gamut, you'll get a not very saturated color that may not need clipping to fit the output gamut.
> 
> If you fit the colors to output gamut first, then do composition, the result will be different (and worse).
> 
> * output: because if all the things you are compositing do fit in the output device's gamut, doing composition directly in that space will be close enough to what you'd get using CIELab, but is computationally more efficient.

Compositing in the output gamut is not really close to compositing in
Lab. Try generating a saturated red-green gradient or rainbow in sRGB
and in Lab.

> 
> I'm not too sure why you'd want to do composition in any other space than these 3.
> 
>  - Florian
> 

Received on Tuesday, 22 March 2016 16:57:01 UTC