[Openicc] Gutenprint mission as Linux moves towards color managed workflows

[Robert Krawitz]

On Sun, 13 May 2012 12:40:31 +0200, Till Kamppeter wrote:
> On 05/13/2012 12:53 AM, edmund ronald wrote:
>> Gutenprint has provided general print services for Linux users, but it
>> has also acquired a constituency of print professionals who use
>> externally color-managed workflows to drive legacy hardware. A typical
>> use of a professional externally color-managed workflow is "Photoshop
>> Manages Colors" driving a Linux printserver where an external instance
>> of Photoshop effects the color conversion to deviceRGB by means of
>> Adobe's CMM, and a user-supplied profile.
>>
>> We understand the aspiration of integrated seamless color management
>> as proposed by the members of OpenICC. We too have subscribed to this
>> effort to provide better color for desktop Linux users. However, we
>> have responsibilities to our historical constituency, and we cannot
>> require existing users to abandon their workflows on the promise that
>> future Linux color management will magically replace decades of
>> proprietary development.
>>
>> Therefore, we believe that any new print solutions that we support
>> should *also* fully enable the historical CM-off print queues
>> as these are important for our existing userbase. These are also essential
>> for our contributors  as engineering and diagnostic tools.
>>
>> If the new code requested for color-management support does not
>> integrate the functionality of the old, then those new developments will be
>> relegated to our spare time, as our main effort goes into supporting
>> the existing users and providing drivers for new hardware.
>
> What we need here then is a standardized CUPS filter option (like there are already options as "number-up", "page-ranges", ... in the CUPS filter system) to turn off color management. It could be a boolean option named
>
>     color-management
>
> which is set to "on" by default and sending a job with the command line option or IPP attribute
>
>     color-management=off
>
> would execute the job with the normal filter chain but all color management being turned off.
>
> Supplying this option makes CUPS simply add "color-management=off" to the fifth command line argument of all filters it calls, so the filters could react appropriately.
>
> The option default can be also changed with an entry in /etc/cups/printers.conf (which can be generated by the "lpadmin" command.
>
> On Linux systems these are all filters calling Ghostscript, which means gstoraster (ghostscript package), pdftops (cups-filters package), foomatic-rip (foomatic-filters package). They are all under my maintainership and I would add the option without problems. I would also contact free software driver developers to add the option if needed.
>
> Richard, could you help me to get the "color-management=off" option correctly implemented in the mentioned CUPS filters? Thanks.
>
> For Mac servers we will need to contact Mike Sweet, as filters of the Mac's proprietary PDF workflow will have to get changed.
>
> It would be also very easy to add a checkbox option to any printing dialog which makes the jobs being sent with "color-management=off" or "color-management=on" depending on the setting. I would call it something like
>
>     Turn off color management (for calibration)
>
> and put ity into some "Advanced" group. But this has to be decided by the desktop UI designers.

This issue seems to have been stuck for a while.  Any chance we could
get it unstuck?
-- 
Robert Krawitz                                     <rlk at alum.mit.edu>

MIT VI-3 1987 - Congratulations MIT Engineers men's hoops Final Four!
Tall Clubs International  --  http://www.tall.org/ or 1-888-IM-TALL-2
Member of the League for Programming Freedom  --  http://ProgFree.org
Project lead for Gutenprint   --    http://gimp-print.sourceforge.net

"Linux doesn't dictate how I work, I dictate how Linux works."
--Eric Crampton