[Openicc] Linux CM ideology, was: meta data in test chart

[Chris Murphy]

On Jan 27, 2011, at 3:27 PM, edmund ronald wrote:

> On Thu, Jan 27, 2011 at 10:19 PM, Chris Murphy <lists at colorremedies.com> wrote:
>> I am a subject changer.
> 
>>> Gutenprint people for a long time wanted to improve colour through ICC conversion by default. The need to comply to the PDF standard seems a further hint for this direction to go.
>> 
>> Fine. That seems straightforward and with minimal GUI changes. And I like the idea of ICC by default. That will reduce a LOT of driver and workflow confusion by users. It's one of the great mysteries to me that Apple and Microsoft capitulated and allowed non-ICC proprietary printing to be the default on both of their platforms.
> 
> At the moment, I believe the Gutenprint stance is that we would like
> to be sent print settings and have an associated profile applied
> upstream by the OS, or if necessary I guess we could apply it
> ourselves. If someone wants to nail this down further at this stage, I
> would welcome the education, otherwise I guess things will end up ...
> hacked on top of the DeviceRGB and DeviceCMYK pipelines which we have
> I believe accepted all accepted as necessary.
> 
> Notice that the door opens again on the dreaded "Application Color
> Management" issue, if an app thinks it can apply ICC "better" than the
> OS, it needs to be able to get the print queue, get the profile, do
> its magic, and write DeviceRGB or DeviceCMYK to the queue.
> 
> As I said, I welcome education on this topic.

If the print spool file format is going to be PDF, then:

a.) Upstream there is something, a share or private library, that's responsible for the creation of the PDF print spool file and it will need to know how to properly tag objects in the PDF for color management; and will need to know the special tag to use to prevent color management from occurring.

b.) Downstream, I'm hearing that it would be GhostScript+lcms that will eat the PDF, color manage and rasterize it. So really the mechanism for how to ensure no color management needs to be discussed with them.


Chris Murphy