LightZone reborn as free software

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One of the first high-quality raw photo editors available for Linux desktops was LightZone, but although it was (initially) free of charge, it was a proprietary product. Unfortunately the small company behind it eventually folded, and both the free and paid versions went away, as did the updates required to support newer cameras. The company shut its doors for good in 2011, but the software has made a sudden—and unexpected—comeback as an open source project. Fans of the original will be pleased, but the nascent effort still has considerable work ahead before it grows into a self-sustaining community project.

Flashback

LightZone was launched in mid-2005, first for Mac OS X, followed a few months later by Windows. But the application was written in Java, and in 2006 a developer at parent company Light Crafts began building it for Linux as well, posting the bundles (with permission) on his personal web site. The response was positive enough that Light Crafts soon began providing LightZone for Linux as an official release—one which, unlike the offerings for proprietary operating systems, was free. Perhaps that situation was bound to change (after all, there was evidently money to be made), and Light Crafts did eventually start charging for licenses on Linux, too.

But 2006 was also the year that resident 800-pound gorilla Adobe dove into the raw photo editor space with Lightroom and Apple's Aperture (which had been around in less-feature-filled, 1.0 form since 2005) really took off. Before Apple and Adobe entered the market, many small companies offered raw photo converters, but the heavyweights captured market share quickly. New point releases of LightZone continued to arrive, but with few major additions to the tool set. The last new version was LightZone 3.9, released in early 2010. Light Crafts shut down in 2011.

But the application's fans were still there; users seemed especially fond of LightZone's unique tools, which offered editing options not found in competing applications. These included an exposure tool designed around Ansel Adams's zone system and the ability to apply adjustments to one part of an image only by outlining regions directly on the canvas—plus a general reputation for ease-of-use. A user community emerged at the site LightZombie.org, providing updated versions of the dcraw library (on which LightZone's raw file decoding functionality depends), support files for new camera models, and (after the Light Crafts site went offline) Internet Archive links to the installer packages. Customers who had purchased a license key could still install and activate the archived packages, or use the built-in 30-day trial period.

Reboot

After Light Crafts closed up shop, visitors to the LightZombie site began lobbying to have the source code released. The site's administrators discussed the idea privately with former Light Crafts executives, but never made any progress—until December of 2012, when LightZombie's Doug Pardee posted a cryptic announcement that "In a few days, the LightZombie Project will be replaced by something much grander." There were other hints that the code might be released after all, such as the announcement that Anton Kast, the developer who had made the initial Linux port while at Light Crafts, had joined the project.

On December 22, Kast announced that he had convinced the rights holders to release the source code, and made it available at GitHub. Initially Kast made a direct import of the 3.9.x codebase, complete with the license-key-activation modules, without any documentation, and designed for the proprietary build system in use at the company. The LightZombie site was renamed LightZoneProject.org, and maintainers put out a call for volunteers in January, to which several Linux and Windows developers responded.

In the weeks since the initial release, the focus has been on getting the application to build and install successfully with free tools. The commercial product was packaged for distribution with Install4J, although as Kast pointed out on the developers' discussion forum (which at the moment seems to require membership in order to view messages ... ) that there may be little real need for an extra packaging layer, since wrapper scripts were used to launch the application on all three platforms. The IzPack tool was suggested as a plausible open source replacement, although so far it remains an open topic of discussion.

A bigger issue is the version of Java required. The commercial 3.9 release bundled its own version of Sun's Java 1.6, which was already out of date when Light Crafts ceased operations. It also relied on several Sun image processing classes that are no longer available, and some classes imported from Java Advanced Imaging (JAI) that were not part of the official JAI release at the time of 3.9's development. In addition, some Linux developers expressed an interest in getting the application to run on OpenJDK since it is the default on several major Linux distributions.

Over the following two weeks, though, the developers managed to successfully replace the Sun classes with modern equivalents, and used Apache Ivy to automatically pull in a current version of JAI at build time—a strategy employed by other open source projects. For now, Pavel Benak's branch is the focus of development, and the Linux port currently builds on Ubuntu and Arch Linux, either with OpenJDK 6 or 7 or with Oracle's Java 6, 7, or 8. The Windows build is reported to be working as well, albeit only with Oracle's Java 6. The Mac OS X platform, however, has seen no development so far due to a lack of volunteers.

Let there be zones

As advertised, the codebase on Github is essentially unchanged since the last commercial release of LightZone. Pardee has updated the dcraw library and support files, so newer cameras are supported, but the application still asks for a license key at start-up. However, the 30-day trial period is still enabled as well—a time period that can be reset at will.

The majority of the tools will feel familiar to anyone who has used another raw photo editor; just like the competition, LightZone allows the user to stack together a string of image adjustments by adding them to a list on the right hand side of the window. But LightZone does offer some tools not found in other open source photo editors. One example is ZoneMapper, the Ansel Adams–inspired tool mentioned earlier. Adams's "zones" are essentially ten stops between absolute black and absolute white. ZoneMapper presents a rectangle with ten handles on it corresponding to each of the zones, the user can drag the cut-off points up or down and the zones on either side are compressed or expanded as a result. The same effects could be performed with the traditional Levels or Curves tools, but ZoneMapper is much easier to use.

I stopped using the proprietary version of LightZone when it was no longer free (there were, after all, free software alternatives). As a result there are several new features that were new to me, although commercial LightZone customers will find them familiar. One of these is the Relight tool, which automatically brightens underexposed portions of the image. This, too, is an operation that can be done by hand with other tools, but what makes it worth mentioning is that it works quite well without manual intervention.

Not everything in LightZone is perfect; for example, the noise reduction tool crashed the application every time I tried it. Still, it is encouraging to see how well LightZone works considering that the open source project is barely a month old. End users may wish to wait until stable packages are available, but LightZone will hold its own against Rawstudio, UFRaw, Darktable, and RawTherapee. Developers from those competing projects may find the source to be interesting reading as well; in addition to the unusual tools, LightZone enjoyed a reputation for high-quality grayscale conversion and for good tool presets.

The road ahead

Obviously working out the bugs is important, but LightZone as a self-sustaining project has a more difficult task ahead of it in other areas. For starters, the project needs to formally decide on a license. The copyright document in the source tree was imported with the rest of the code; it bears a short, BSD-like copyright statement from Light Crafts' founder Fabio Riccardi and a 2011 date, but the project will need to make this clear. Moving forward, as Tex Andrews posted on the new project site, the group will have to start work on documentation, translations, and discuss "certain organizational issues that now confront us."

Andrews and Pardee, who managed the LightZombie project for more than a year, have cultivated an enthusiastic user base. That will supply the new project with momentum, but it does not guarantee that it will thrive. Keeping a community project alive takes considerable effort, as just about anyone in free software will attest. At the moment, the volunteers have updated dependencies and repaired the build system in short order, but the real work of refactoring the code and improving it has yet to start (case in point being the license-key activation, which should be straightforward enough to remove).

Nevertheless, the new project is a rare gift to software users. Many a small commercial application has vanished for financial reasons and had its disappointed users lobby for the release of the source code. Most of these appeals are unsuccessful. But these lobbying efforts have the potential to turn into successes—consider Blender, for instance. LightZone will at least get a second chance to win over users, which is an opportunity few applications see.