[Openicc] CUPS Color Management under Linux gets into distros

[Kai-Uwe Behrmann]

Hello Till,

Am 08.02.11, 17:33 +0100 schrieb Till Kamppeter:
> [ This mail is posted to the OpenICC mailing list, Please always reply
>  with "Reply to all" so that it gets to the list and all CCs. Thanks. ]
>
> Hi,
>
> we will have some color management in a distro soon. I have added Koji 
> Otani's Poppler-based pdftoraster filter to the CUPS package for Ubuntu Natty 
> (release end of April, currently available as the development branch of 
> Ubuntu) and Debian unstable. This pdftoraster filter replaces the one shipped 
> with Ghostscript and in addition to being much faster and more reliable with 
> complex PDFs it implements CUPS' ICC profile support as described in the 
> documentation:
>
> http://www.cups.org/documentation.php/doc-1.4/spec-ppd.html#cupsICCProfile
> http://www.cups.org/documentation.php/doc-1.4/spec-raster.html#TABLE2
> http://www.cups.org/documentation.php/doc-1.4/raster-driver.html#COLOR
>
> Otani-san, am I correct that with this pdftoraster we have ICC-profile 
> support for CUPS Raster drivers as described in the CUPS doc? How do I supply

Great news. A ICC enabled pdftoraster filter is a huge step forward for 
colour managed printing. Many thanks for your work on that.

> a rendering intent? Are there any additional non-PPD options to supply to 
> print jobs?
>
> Color management experts from OpenICC and driver developers, please test this 
> feature and report your experience here. You could ship ICC profiles for 
> installation in /usr/share/cups/profile/ to improve your printer's output 
> quality.
>
> 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.

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 testing you need the PDF printing workflow:
>
> https://www.linuxfoundation.org/collaborate/workgroups/openprinting/pdf_as_standard_print_job_format
>
> This is already implemented in Ubuntu and Debian and the newest snapshots of 
> Natty and unstable contain the new pdftoraster. Do a complete system update 
> ("sudo apt-get update; sudo apt-get dist-upgrade") after having booted or 
> installed the system from a daily live CD or Alpha version. You must have the 
> package cups of version 1.4.5-3.

Thats wonderful.

> On other distributions you have to install the PDF workflow by compiling from 
> source, following the instructions on the page linked above.
>
> Please report your experience here and discuss.
>
> Patches are also welcome to make the pdftoraster of Ghostscript implementing 
> CUPS' ICC profile support.
>
>   Till
>
>
> P. S.: In April there will be also a session on the OpenPrinting Summit about 
> Color Management for printing with Linux.

kind regards
Kai-Uwe Behrmann
-- 
developing for colour management 
www.behrmann.name + www.oyranos.org