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DistributionsGuacamayo media player distributionGuacamayo is a new entrant in the field of Linux-based operating systems for multimedia devices. Most such distributions (e.g. LinHES or Mythbuntu) start with a desktop distribution and add media management, playback, and other features on top, but Guacamayo's creators Tomas Frydrych and Ross Burton are taking the opposite approach, starting with a minimal embedded system and adding only the software necessary to stream multimedia content. The result, they hope, will be a more stable base for building set-top boxes, network-connected speakers, and other nontraditional media platforms. Frydrych said the impetus for the project was the popular Raspberry Pi device, which offers a low-cost board capable of HDMI output. Despite that inspiration, however, he builds Guacamayo against a different test platform, the pricier (but still lightweight) ZBox, a roughly WiFi-router-sized fanless desktop unit. Frydrych and Burton are both veterans of OpenedHand and Intel (which acquired the former in 2008), and Guacamayo builds on many of the projects created by OpenedHand over the years. It is based on the Yocto embedded Linux platform, uses the Clutter library for its GUI layer, and runs Media Explorer (MEX) as its "shell." For now, the emphasis is on Universal Plug-and-Play (UPnP) and Digital Living Network Alliance (DLNA, which is a consumer electronics compliance organization built on top of UPnP) compatibility through the Rygel library. The first public release is version 0.2, which was code-named "See No Evil, Hear All You Want!" because it supported audio playback only (MEX support has been added subsequently). Burton posted a blog entry about the release on May 22, saying he used it successfully with a UPnP media storage device. In that configuration, Rygel presents the Guacamayo front-end as a UPnP "Media Renderer" that can be remotely controlled by any compliant UPnP or DLNA "Media Controller." In the same post, Burton said that Frydrych had tested the release running on a BeagleBoard being controlled over the network with a Android DLNA control application. Sound offAudio playback alone might not sound particularly exciting, but the next release should add video playback, which is where the system begins to get more interesting. The audio decoding and playback are handled by PulseAudio and GStreamer, both of which are standard system components on desktop Linux. But Guacamayo's video stack is intended to dispense with X Windows, window managers, and desktops entirely. MEX is a simple media browser and player built specifically for Clutter, but Guacamayo's Clutter will run with an OpenGL back-end. That will enable smooth graphics on Raspberry Pi and other such low-power boxes that have hardware-accelerated OpenGL support. ![[MEX on Guacamayo]](/images/2012/06-guacamayo.png)
According to Burton, many of the GPUs in this generation of device are also supported (at least partially) by the video acceleration API (VA-API). GStreamer supports VA-API, therefore Clutter and MEX should be able to take advantage of it as well. On the other hand, Guacamayo can be built for a broad spectrum of hardware devices, some of which might be able to take full advantage of VA-API and some of which might not. Burton noted that his old ThinkPad can decode MPEG2 in hardware, but it can do the job just as easily in software. In contrast, a more recent Cedar Trail Atom netbook can decode the more complex H.264 codec at 1080p in hardware, but is incapable of decoding the same format in software fast enough to be watchable. You can get another taste of the flexibility of the Guacamayo code from the build instructions. The project uses the Poky build system, and at the moment three build options are supported: the headless audio-only release, the video-enabled MEX target that runs directly in OpenGL, and an interim option that runs MEX on X11. Despite how clean and simple the setup is — and there can be little denying that the stripped-down media playback environment of Guacamayo is simple — a few challenges remain. The first is video drivers. Both Burton and Frydrych observed that open source drivers for Intel video chips offer good support for OpenGL (and in particular the EGL interface used by Guacamayo), but that other chipmakers are spottier. Frydrych said that the BeagleBoard drivers "have issues" and "took far more effort than should be necessary," while Burton said that he thought the Nouveau drivers for Nvidia hardware worked well. Still, Frydrych said that he felt that "the OpenGL(ES) route is good enough to bank on," since the chipmakers are aware that they need working OpenGL ES drivers in order to compete in the marketplace. He has yet to see exactly how well the Raspberry Pi delivers on this point, he added, but if they "get it right" it could have a significant impact on the competition. Another challenge is support for input devices and remote controls. The X-less builds use the kernel's evdev interface to capture input events, but without X there is no XInput2 subsystem to enable multi-touch, "multimedia keyboards" or other flashy input devices. Although Rygel gives Guacamayo automatic support for UPnP/DLNA remote controls, infrared is still the dominant flavor of remote control. Burton commented that DLNA and IR remotes are "orthogonal," but that Guacamayo needed to support them both. Platforms versus productsI asked whether Guacamayo was focused squarely at do-it-yourself media devices, or if its creators hoped to see it powering consumer products some day. Frydrych replied that he would rather see Guacamayo grow into a Yocto-based platform that others found useful, and which could be tailored to more than one use case. In that regard, he approaches the project as a set of add-ons that enable Yocto to work on media-centric devices that it otherwise could not, rather than as a separate distribution. The key distinction, he said, is establishing a reliable QA process that makes the distribution maintainable. That is an area where Yocto excels, so it makes for the ideal base platform. Where Guacamayo heads in the future is still up in the air; there is a general roadmap on the project's GitHub wiki, but Frydrych emphasizes that he is more interested enabling others to build a user experience than in dictating one of his own. "Yocto makes it possible to create a tailored Linux device in a very short period of time, taking care of the boring and tedious; Guacamayo should do the same for the multi-media device category." For now the Rygel-driven streaming media interface of MEX is the only application on the roadmap. That may prove popular enough with users to spawn a following; after all the consumer device space is filled with streaming-only set-top boxes. But each generation of set-top box also adds more and more features (e.g., Boxee adding live TV tuning, or Roku adding USB storage and games). It will be interesting to see if future Guacamayo releases entice third-party developers to try something new, and how the project adapts. The X-less OpenGL environment is certainly different. Clutter has an OpenGL GUI toolkit called Mx (not to be confused with MEX), but Burton cautioned that Mx was lightweight in design and was not intended to provide a full application framework along the lines of Qt or GTK+. Both developers mentioned that if OpenGL alone proves not to be enough, they will target Wayland rather than X in future releases. The truly interesting match-up will be to see how video-enabled Guacamayo stacks up against a Tizen set-top box. Despite both projects' interest in media playback devices, they approach the task from starkly different angles. Tizen is concerned (on the set-top front) with providing a complete development environment for consumer electronics manufacturers; the platform offers compatibility with desktop Linux and with the other flavors of Tizen device, and it wants to attract all sorts of independent application vendors. Guacamayo (at least at the moment) is targeting DIY devices first, with a limited application set on a minimal, embedded Linux base. Neither one is necessarily right or wrong, but that's what makes watching them entertaining.
Brief items Distribution quotes of the week
That users are more important than developers. Although in Gentoo
that line is quite blurry, let's be honest: without users, what would
we need developers for? I believe we should first think about making
things more friendly to users, then about making them easier for devs.
Not the other way around.
-- Michał Górny
No, if we have to beg Microsoft for permission to conveniently
install Fedora, we have lost our freedom to conveniently, without
asking permission of Microsoft, install Fedora. Why should we
beg Microsoft for a power which last month we had, and which
Microsoft has seized to itself?
-- Jay Sulzberger
Of course the actions by Microsoft are against anti-trust law in the US and in Europe grossly violate the rule against tying of software and hardware. And claiming "Why you could pirouette and do a handspring backwards, and if Microsoft agrees, then you can install Fedora, so there is no extra bar to installation." is incorrect. Before now we did not have to do the pirouette and handspring. Before the New Microsoft Regime of Booting, we did not have to beg Microsoft to sign our keys.
At some point this tie needs to be broken for good and here is my
suggestion as the election coordinator. If this round also ends in a
tie we do the following:
-- John Rose
(1) Live webcast of the candidates playing rock paper scissors lizard spock. This will last at most 17 rounds. If the candidates both stubbornly refuse to budge from spock for all 17 rounds we go to step 2. (2) Live webcast of the candidates in a 17 minute long hotdog eating contest. Again, we allow for ties and repeat this up to 17 times. If 289 minutes of stuffing themselves with hotdogs does not resolve the matter I think they have both earned a seat on the Board.
Distribution News Debian GNU/Linux bits from the DPL: May 2012Debian Project Leader Stefano Zacchiroli reports on his May activities, starting with the wheezy release. Also covered is the discussion on Debian multimedia, sprints, expenses, and a few other topics.
Bit from the Release Team: armhf and s390xThe Debian release team reports that armhf and s390x architectures have release architecture status for wheezy. Bugs specific to these architectures may be release critical and could delay the release of wheezy (Debian 7.0).
Fedora Election Results for Fedora Board, FAmSCo, and FESCo seatsFedora project leader Robyn Bergeron has posted results from this week's Fedora Board, Fedora Ambassadors Steering Committee, and Fedora Engineering Steering Committee elections. Bergeron notes that "apparently, we like to keep things interesting around here; the improbable situation of having a tie for a seat has occurred. Read on for details!" There will be a run-off election to break the tie.
Other distributions CentOS: MirrorList.centos.org is now available on ipv6The CentOS project has announced that mirrorlist.centos.org is available on ipv6. "This is a full featured service, using geoip on the server end to hand out local-to-user IPv6 mirrors. Every url handed out is verified at regular intervals and only the freshest ones used."
Scientific Linux 4 EOL and archivedScientific Linux 4 has received no updates since February, but it's remained available in the main repositories. Now it's time for it to move. "On June 12 2012 we will be moving all instances of Scientific Linux 4 into the 'obsolete' directory under /linux/scientific/ . This is the same place that Scientific Linux 3 has been since it was archived. They will be at /linux/scientific/obsolete/
Newsletters and articles of interest Distribution newsletters
CentOS Project Release TimesJohnny Hughes explains the steps the project has taken to address lagging point releases. "We now have corporate sponsors who sponsor 2 CentOS Developers to work on the CentOS Project full time. That means that we now have 80 paid hours per week of CentOS Project time where we get do nothing but CentOS Project related work. The sponsors do not ask for anything in return, just faster CentOS updates by the current CentOS developers who get to make the CentOS Project their daily work priority. This should be huge in preventing future delays."
Interview with Patrick Volkerding of Slackware (LinuxQuestions)LinuxQuestions.org members had some questions for Patrick Volkerding, the founder of Slackware Linux (the oldest Linux distribution still in existence). "I try very hard with Slackware to defer to the wishes of the upstream developers. This isn't the place to be patching in new features, or packaging beta versions (if that can be helped). Lao Tzu said that in order to lead, one must follow. I have my own ideas about how things should work, of course, but I try not to impose them in a selfish manner. The goal is to move forward without abandoning the project's roots. I have nothing against change, but at the same time I try not to let things get juggled around simply for the sake of making them different. People who come back to Slackware after a time tend to be pleasantly surprised that they don't need to relearn how to do everything. This has given us quite a loyal following, for which I am grateful. I guess we're doing something right."
Page editor: Rebecca Sobol |
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