net-color spec renamed to X Color Management

Kai-Uwe Behrmann ku.b at
Tue Sep 27 23:12:10 PDT 2011

Am 27.09.11, 21:53 -0600 schrieb Matt Dew:
> Is this related to GNOME's color management stuff in this article:

I guess Gnome is discussing colour management inside the toolkit. But they
have not yet much outlined on the Gnome email list, what they really 
want, let alone what strategy to take. This article is fuzzy in this 
regard as well.

So they might want to write to a own offscreen texture, do compositing in 
a internal engine and write that to a final screen buffer in monitor 
space. In this case the value of the X Color Management spec is, that a 
toolkit can offload the correction of a transformed drawing to a window 
Thus it needs to handle fewer implementation details just for fuzzy 
animation effects. The X Color Management spec acts then like a 
integration point for various toolkits, who deploy the same common colour 
correction technic. If Qt uses the same spec then they can work seamless 
together. The same happens for Gtk applications on KWin.

One major pit fall related to colour management is a missing concept of a 
intermediate blending colour space. But that needs to be made clear very 
early in the architectural design process of a colour management strategy. 
If that is solved internally of the clients/toolkits, then the X Color 
Management spec can be correctly deployed. If it is not, they have 
problems all over with colour management.

I have elaborated a bit more in a blog article for interessted readers:

kind regards
Kai-Uwe Behrmann
developing for colour management oy at freenode#openicc

> On 09/26/2011 12:21 AM, Kai-Uwe Behrmann wrote:
>> The net-color spec from the libXcm repository is renamed [1].
>> The _NET_ prefix is reserved inside the Xorg atom name space. The new
>> prefix is simply _ICC_.
>> The new spec draft is called X Color Management [2]. It contains the
>> color regions in Xorg description and the device profile for Linux
>> desktop colour servers.
>> Affected are libXcm, Xcm, Oyranos, CompICC and CinePaint. They are all
>> updated and will contain the changes in their next releases.
>> The spec allowes a client/server communication about colour correction
>> on the GPU by compositing window managers.

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