[Openicc] CUPS Color Management under Linux gets into distros

[Till Kamppeter]

On 02/08/2011 06:04 PM, Kai-Uwe Behrmann wrote:
> Great news. A ICC enabled pdftoraster filter is a huge step forward for
> colour managed printing. Many thanks for your work on that.
>

Also thanks to Otani-san who wrote this filter and also many other PDF 
filters.

>> Color management experts from OpenICC, WDYT about this color
>> management effort? Is this already a step forward? Is it at least the
>> correct effort for
>
> Yes, such a pdftoraster filter is a pre condition for any main stream
> colour management on Linux.
>
>> consumer-level printing? What needs to be added to support pro and
>> prosumer printing?
>
> I think consumer lever printing with canned profiles might be already
> served to some degree by your announced changes and CUPS capabilities.
> Vendors can bundle their drivers, PPDs and ICC profiles to deliver a out
> of the box improvement. The same for administrators to setup colour
> managed queues.
>
>
> The recent weeks we discussed here on OpenICC in length about user side
> colour managed printing. As PDF, CUPS, Poppler/Ghostscript and CPD are
> rather complex, we had many thoughts about it. The question was more or
> less, how can users opt-out of colour management
> for calibration. And how to assign own profiles to a print job to
> override the PPD configured profiles. As well passing rendering intent
> and black point compensation options is yet unclear to us.
>

Otani-san, if one has a print queue with installed ICC profiles, is 
there an easy way to turn off ICC color management with your 
pdftoraster? This way advanced users could do a calibration to create 
their own ICC profiles. Also can one override the PPD's ICC profiles to 
use user-supplied ones (for example embedded in the pDF job)? What about 
sending rendering intent and black point compensation along with a job? 
Can you, if needed, add options to the pdftoraster and/or the 
possibility to read info/data embedded in the PDF jobs?

> I tried to summarise some of the issues without giving it a proper
> architectural shape yet. However these notes might help to understand
> where the discussion stands:
> https://www.oyranos.org/wiki/index.php?title=Device_Settings#Printing
>

For the "wget http://localhost:631/profiles/sRGB.icc" problem, there is 
an STR on

http://www.cups.org/str.php?L2896

Please add your comments.

A possibility to send user-supplied profiles along with a job could be 
embedding the profile in the PDF job. The Common Printing Dialog would 
be the best place to do this. pdftoraster would need a feature to read 
out such profiles and use them instead of the PPD-specified ones.

You should mention on the Wiki page that Poppler supports ICC color 
management, too.

    Till