Linux Color Management Hackfest 2012

The hackfest in Brno is approaching fast. I wrote earlier this year about the idea. It will happen from 9th until 12th November 2012 inside the Red Hat Czech office. Talks with our local organiser and various sponsors went good so far. People will code in Brno on various topics around color management in Linux.

The main focus looks like to be at applications, desktop and library integration. For the printing system and Taxi DB was good interest too. As the event is organised as a framework for attendees, each one will decide, what is best to do. After a morning meeting, where we can coordinate, we will likely split in smaller groups according to a choosen topic or move around as needed. We hope that works for all attendees. There are specialists present for many Linux color topics for discussion and of course color management newbies can ask them to effectively improve their project.

Little CMS 2.4 released

Version 2.4 is a featured release that introduces new functionality as
well as many performance and security improvements.

Main additions are:

  • Black point detection from the algorithm disclosed by Adobe
  • Added support for transforms on planar data with different stride
  • Added a new plug-in type for optimizing full transforms
  • Linear (gamma 1.0) profiles can now operate in unbounded mode
  • Added “half” float support

The last point of 16-bit floating point support is much requested from e.g. the Krita project.

 

OpenICC Google Summer of Code 2012 results

Google Summer of Code

Participation of the OpenICC group in the Google Summer of Code 2012 program was this year a great success. All projects reached their respective goals. Here a small summary:

Colour Management for Krita Printing
Joseph Simon worked on adaption and integration of his last years implementation for colour managed printing into Krita/Linux. The workflow is based on ICC profile injection into PDF through the means of a OutputIntent.

KWin Colour Correction
Casian Andrei’s KWin changes for ICC style colour correction in the GPU are reviewed upstream and his new code to the KolorManager code base waits just for approval. The concept follows the X Color Management spec. In contrast to the elder CompICC implementation is the KWin result highly modular and thus very flexible.

Simple Toolkit Abstraction
Nitin Chadas SimpleUI project for rendering a subset of XForms was written from
ground up and provides now backends for FLTK, Gtk and Qt. It needs a bit
of polishing to become useable.

Thanks to Google for providing the colour management and graphics community again a great chance to code and learn the open source way.

LibreGraphicsMeeting Videos

In begin of May there was the 7th LibreGraphicsMeeting in Vienna and Oyranos participated also this year in this meeting of nearly all free/open source graphic software. Oyranos had two talks there and I already blogged the impressions. Now the most of the videos from the talks are online.

The playlist with all talks which was recorded can be found here.

ICC profile graphs

During the recent days I improved the file dialog preview of ICC Examin. As a result I created a new Oyranos tool called oyranos-profile-graph, which can be found in git. It provides a simple icon and can potentially be used in tools like Synnefo or KolorManager‘s info tab.

There exist some graphing tools like ppmcie to generate a nice triangle inside a CIE*xy horse shoe.

CIE*xy graph from ppmcie

But as ICC Examin sticks on CIE*Lab, I think it is more appropriate to use the CIE*a*b projection instead. Both are available by oyranos-profile-graph. The graphical output of the tool is really simple, beside using Cairo for antialiased curves. Below are the 2D graphs for sRGB.icc LStar-RGB.icc ProPhoto-RGB.icc ISOcoated_v2_bas.ICC ISOuncoatedyellowish_bas.ICC profiles. The first graph is CIE*ab and the second shows the same saturation lines in CIE*xy.

 

Linux Color Management Hackfest idea

Sirko brought up the idea to organise a hackfest together with developers of applications for Linux desktops and experts interested in colour management. The idea behind that event was to bring interested developers together, support them in implementing color management in their software and move forward that topic across desktops and distributions.

During the recent LGM we found a chance to involve Richard Hughes and planed together about what we like to do during the hackfest. We spotted three main areas of interest: desktop applications including window managers, web browsers and printing. These topics are already worked on, but in a scattered way.

As example, Gwenview is a really great application for managing pictures. But it has no color management implemented yet. Color management in KWin is worked on during the GSoC this year, but in the opposite color management in the compositing manager mutter on the GNOME side is far away as can be read here. Not many web browsers support color management and if they who do, it is often incomplete. The SVG v2 standard will for example introduce additional color management features compared to SVG v1. So it is now the right time to get these implemented in order to be well prepared. For the KDE printing stack there is also a GSoC project this year, but also the Linux Foundation has a working group for this topic.

So, by meeting in person in one place, we want to get something done and build a good understanding of the role of each participating group for a working end to end colour management.

The hackfest will very likely happen in Brno in the Czech Republic at the Red Hat offices. A good time appears later this year 16th till 19th November. Now we like to collect more ideas, speak to people and sort financial issues.

Colour Management Talk @ LinuxTag 2012

Logo LinuxTagEuropes biggest event arround Linux and Open Source – LinuxTag, is’nt far away anymore and Oyranos will participate on it. LinuxTag take its place in Berlin from 23.-26. May on the exhibition area arround the Funkturm. On saturday the 26th of May I will present together with Sirko an talk about colour management – “Bring Color To The Game“. The talk will not introduce Oyranos as CMS, it will more explain what color management is and about the actual status on free desktops. We want as well to talk about what a user needs to get colour management running. During LinuxTag I will be reachable on the openSUSE booth for questions and introduction into profiling and bring some colorimeters.

LGM 2012 Impressions

The Technikum Wien provided a nice place and great support for the LibreGraphicsMeeting. Many thanks to them. LGM happened together with the Linuxwochen Wien and developers and users could talk about graphics and arts themes. Additionally to the one presentation track over all days, we had BoF’s and workshops. Some of us took the chance to present to a non LGM audience and meet people there too.

The LGM talks covered lots of OpenCL projects. That means modern GPU computing power is available to open source graphics components in a much broader way. As the use of OpenCL is supported by the Mesa software implementation, there is some kind of guarantee, that OpenCL programs will run on elder hardware. That means OpenCL can be used without the need for developers to provide a fallback mechanism, which simplifies adoption.

The colour management talks provided lively discussions around many topics like printing, displaying and open hardware. We discussed as well the impact of introducing colour management in frameworks like GEGL. As mizmo showed interest, I explained the most basic terms of ICC rendering intents in a small BoF using ICC Examin. Animtim compiled and installed Oyranos from sources and wrote already a small tutorial on how to build Oyranos on kubuntu-12.04.

Markus Raab with Elektra on LGM 2012 Vienna

Markus Raab presenting Elektra on LGM 2012 Vienna

The presentation of Markus Raab about the Elektra configuration gave to me some impressive insights into the concepts and flexibility of that small framework. The really cool thing about this library is it can abstract a lot of details and provide additional features, which can be added on run time like DBus support. He announced a new release of Elektra as version 0.8.0 during the event.

The metalab was for most people from countries without a similar open hardware/open source collaboration zone a impressive visit. We all enjoyed to could stay there for some hours and felt, this place is much in the spirit of most LGM contributors.

Nathan Willis @ LGM 2012 Vienna

During Nathan Willis workshop about the Create wiki, we discussed to start a email list for create users. That list is supposed to provide help and talk about experiences with graphics applications and help from users for users.

Sirko (alias gnokii) and Tobias (alias houz) played diplomat and managed to channel information in a way that Richard Hughes and I could finally meet in a productive atmosphere and continued talking about technical issues. At the end we found a mod to work again together on standards inside the OpenICC collaboration project. I am pretty happy with that change. So, thanks to all parties who helped with that.

Café Hawelka Vienna

Tatica, Pete, Sirko and I walked around on the last day in Vienna and relaxed in the café above.

OpenICC Google Summer of Code 2012 projects

OpenICC obtained three project slots for the Google Summer of Code 2012
stipends. That means three students can work again this year full time over
three summer months on colour management projects. Thanks to Google for
organising and sponsoring the program.

Here are in short the projects:

Joseph Simon will continue to work on PDF colour management for the
KDE/Linux printing stack. To have a real world project he choose to implement
Colour Management for Krita Printing.

Casian Andrej will work on ICC KWin colour correction using the X Color
Management spec. That way KWin gets a clear path toward consistent colour
output on the desktop.

Nitin Chada will work on different toolkit dependent renderers for a
XForms subset inside the Simple Toolkit Abstraction project. That standalone project shall enable modules to present
options inside dialogs or embedded in host applications.

Lets have a successful coding summer and deserve the trust Google putted in
the OpenICC organisation and with that in the participating students.