[Openicc] Promoting colormanagement for LINUX

[Stefan Döhla]

Am 14.02.2008 um 06:16 schrieb Graeme Gill:

> Stefan Döhla wrote:
>
>> One thing that would ease implementing basic color management:  
>> Trust  the X-server that it renders a colour in a predictable way.  
>> This is  the MS approach: assume sRGB for everything and tell the  
>> apps that,  well, it's not sRGB and you are better off doing this  
>> inside the  application. If the combination OS and video card were  
>> smarter all  colours would be mapped from sRGB to the monitor color  
>> space.
>
> You can do that, but you immediately curtail what you can use the
> system for. The basic nature of all this is that different devices
> have different gamuts, and there is no uncontroversial way of
> mapping from one gamut to another. There are always trade-offs,
> and differing purposes. You can pick a subset common gamut, but
> then you can't make use of a devices full capabilities. I think
> if you'd just spent $$$ on a wide gamut monitor, you wouldn't
> think much of this approach.
> Most serious photography people don't want sRGB, they want something
> with a larger gamut (AdobeRGB is popular).

Yes, but let me rephrase it: MS promotes scRGB and 16bpc for "serious"  
applications. All apps that send data in this format to the OS can  
expect that it renders it the way the user has configured the system.

sRGB is just meant for old apps and "backwards compatibility" (at  
least that's what I understand from the MS presentations).


>
>
>> My impression is that X11 will not go this way since they don't  
>> want  to deal with color conversion inside the server - especially  
>> if this  is something that is configured externally (i.e. by  
>> profiles) which  adds dependencies and internal complexity.
>
> This is sensible. There is a lot of commonality in color management,
> so it can be (ideally should be) a common sub-system, not re- 
> implemented
> over and over for each device.

Right. And what I meant was the X11 guys implementing the MS approach.  
Any other common component could do that as well - but the X-Server is  
probably the most sensible place to do the display color  
transformation (and nothing more). And at the samt time saying that I  
doubt that the X11 guys would do that soon because they need then a  
color managament architecture in the background that creates device  
links from sRGB->display (8bpc) and scRGB->display(16bpc) and  
eventually AdobeRGB->display (but especially the last one exposes  
color management to the user and adds API complexity).

- Stefan