New projects at Libre Graphics Meeting 2014

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Libre Graphics Meeting 2014 kicked off in Leipzig, Germany on April 2. Now in its ninth year, the annual conference and workshop attracts developers from virtually every major open source creative graphics project. The list of participating teams is an ever-growing one, and the first day of LGM 2014 included the announcement of several new projects, in addition to some interesting commentary about the future of some well-known open source projects.

In fact, the number of participating projects has become so large that this year's first session was dedicated to a "what's new" overview of the recent work in many of the mainstream, established projects (GIMP, Inkscape, Blender, Scribus, and so on). The purpose, of course, was to free up some additional session slots for more in-depth topics and less familiar projects that might require more introduction. Øyvind "Pippin" Kolås from GIMP and GEGL acted as emcee for the overview.

The fresh

In addition to the "regulars," four new projects were presented on the first day of the event. The first was Roman Telezhinsky's Valentina, a cross-platform pattern-design application. As Telezhinsky explained, Valentina allows users to design and adjust garment patterns based on parametric measurements of the wearer. Such measurements (limb and torso length, various widths, etc.) are simple and linear, but adapting them into the un-folded and un-cut pattern segments that need to be made in actual cloth requires a fair amount of math. There is very little open source software that addresses pattern-making, so Telezhinsky had to define his own file format, but he is hopeful that the application and the ability to easily share patterns will be valuable to the design community.

Jonas Öberg and Artem Popov spoke about another new effort, Commons Machinery, which is writing tools to preserve and propagate attribution metadata in digital files. Primarily, this attribution metadata refers to the original creator(s) of an image file and perhaps when and where it was created or published. The current lack of a way to preserve this information, they said, is what leads to the proliferation of vague attribution notices like "Photo from Wikipedia"—a statement that, while true, does not help the reader find the original. The project's first work has been extensions for GIMP, LibreOffice, and Firefox that preserve attribution information in RDFa format, but there is more substantial work still to come, such as a distributed attribution database that will soon go online at Elog.io. There is still more to do, they said, but their code can already handle some complex scenarios, like merging the metadata of multiple files that are combined into a single image.

A surprise on the schedule was the announcement of the Document Liberation Project, a spin-off of the LibreOffice project's file format reverse-engineering and conversion work into a standalone project. Team members Fridrich Strba and Valek Filippov had presented their work at LGM 2013, but at that time it was formally tied to LibreOffice. By making it a standalone project (though still one under the governance of The Document Foundation), Strba said, it would be easier to get developers to contribute code without feeling like they were defecting to LibreOffice. The move also acknowledges the reality that many other applications already use conversion libraries created by the team, and it will allow the team to focus more fully on building good cross-application code. In addition to the announcement, Filippov provided an overview of recent work by himself and the third co-presenter David Tardon, such as support for the Adobe Pagemaker and Apple Keynote file formats and improved reverse-engineering tools like a binary diff viewer.

The last new project on the schedule was Lasse Fister's Multitoner, a GTK+ application for working with multi-tone images. The most familiar multi-tone images are duotones, but the general term encompasses tri-tone and quad-tone images, too. All of these images are ways of reproducing a grayscale image with multiple colors of ink mapped to different portions of the black-to-white gamut—in a sense, an extension of the "sepia tone" effect. The difference, naturally, is how many colors are used. Although popular in Adobe Photoshop, there has never been a free software multi-tone tool before, so Fister reverse engineered the Encapsulated PostScript (EPS) files produced by Photoshop and wrote his own. He is in the midst of preparing a printed book of multi-toned photographs with the results.

First appearances

In addition to the four projects discussed above, all of which were launched over the past year or so, there were several other projects that, while a bit older, were presented at LGM for the very first time this year. Dialogue Maps, for example, is the product of a university research project to create interactive visualization diagrams. Presenters Arno Sagawe, Rüdiger Heins, and Janis Bullert compared Dialogue Maps to the familiar Sozi presentation tool, although it incorporates organizational ideas akin to other topics like mind-mapping as well.

Christian Stussak presented SURFER, a real-time ray-tracing application tailored for algebraic surfaces. SURFER was originally intended as an educational tool—hence the focus on mathematical objects rather than general-purpose rendering—but Stussak said that artists soon began designing purely aesthetic creations as well. In an interesting bit of history, he also noted that SURFER was inspired by the mathematical designs that used to accompany SUSE Linux releases; those forms were created with an older open source program that has long since fallen out of maintenance, which provided a good excuse to create SURFER.

David Tschumperlé, Patrick David, and Jérome Boulanger presented a talk about G'MIC, the image-filtering framework most often seen as a GIMP plugin. But there are other ways to use G'MIC's vast collection of image filters, they said, including a C++ library, a command-line tool that functions similar to ImageMagick, and the newest addition, an online editor. They demonstrated several impressive G'MIC filters, including several that were developed as part of the project's intentional effort to work with artists to build real-world tools. Examples of that included a collection of several hundred analog film-simulations developed by David (a professional photographer), and a colorizing filter developed for comic book work in conjunction with Krita's Timothée Giet and David Revoy.

The Magic Lantern project, which creates open source replacement firmware images for Canon digital cameras, was introduced in a talk by Michael Zöller and Alex Dumitrache. Zöller provided an overview of the project and its history, including how volunteers start and maintain each individual camera port—using a model similar to the one used by the mobile phone jailbreaking community. Dumitrache then explained in more detail the process that led to the widely reported dual-ISO shooting feature in mid-2013. Although the initial goal was to figure out a peculiar quirk he encountered with still images, debugging that quirk led to the discovery of the dual-ISO capabilities of the hardware, which ultimately opened the door to other new features like recording uncompressed raw video at HD resolution at high frame-rates. Those features make Magic Lantern significantly more powerful than the stock firmware from Canon, and competitive with professional products like Red Digital Cinema cameras.

Last but certainly not least among the newcomers was Entangle, the tethered camera control application written by Daniel Berrangé. First, Berrangé explained the background of the project, which initially aimed to reproduce the feature of proprietary software from Nikon and Canon that lets users focus and shoot their cameras from a computer connected via USB cable. That sort of functionality is useful in a lot of situations, he said, such as macro photography (where the camera LCD screen is too small to assist in fine-tuning) and astrophotography (where the camera can be attached to a telescope in physically inconvenient orientations). As one might expect, however, there have since been other uses found, such as stop-motion animation. Berrangé noted that stop-motion animators had been a valuable resource and had provided lots of new feature ideas and feedback.

There are still three more days to go in LGM 2014, so there may be many other new projects making their debut over the course of the week. That can make for a lot of new information to take in, but it certainly bodes well for the state of free software graphics.

[The author would like to thank Libre Graphics Meeting for assistance to travel to Leipzig for LGM 2014.]

