Shotwell moving along

I have released 0.25.0 on Monday.

Contrast Tool

contrast-toolA new feature that was included is a contrast slider in the enhancement tool, moving on with integrating patches hanging around on Bugzilla for quite some time.

SSL certificate handlingcertificate-warning

A second enhancement that was introduced is the option to override invalid SSL certificates. This is currenly only available in the Piwigo publisher and might be added to Gallery3 in future, i.e. all services that might be self-hosted on self-signed cerfificates.


Enhanced ACDSEE support

0.25 introduces the support of reading ACDSEE’s proprietary image tags such as titles, categories and hierarchical tags!

If you want to try it, there’s a new, unstable, PPA for Shotwell at



Say you have a shared library with versioned symbols that has the function init(int *param) defined in two versions, where new_init is made the default for init (that’s what the  @@ means):

#include "shared1.h"
void new_init (int *param)
    *param = 0;
void old_init (int *param)
    *param = -1;
__asm__(".symver new_init,init@@VERS_2");
__asm__(".symver old_init,init@VERS_1");

Say you have a second shared library that provides a function do_something() uses that init from the first shared library:

#include "shared1.h"
int do_something ()
    int var;
    init (&var);
    return var;

And you have an app that just prints the result:

#include "shared2.h"
#include <stdio .h>
int main(int argc, char *argv[])
    printf ("Result: %d\n", do_something ());
    return 0;

And all of this is cobbled together with the following Makefile:

all: app shared1.c shared1.h
    cc -o $@ $< -shared -fPIC -Wl,--version-script=version.script shared2.c
    cc -o $@ shared2.c -shared -fPIC
app: app.c
    cc -o $@ -L. app.c -lmoreshared -lshared

What’s the output of


Update: Try to answer it without compiling and running it at first.
Update2: I forgot the version.script, sorry.

VERS_1 {
VERS_2 {
} VERS_1;

More updates

SystemD conf 2016

I will be giving a presentation at this year’s systemd conf in Berlin. If you ever wondered what the hell I am doing during the day, there’s your chance to get a glimpse 🙂

GUPnP going 1.0!

Parts of GUPnP (that is its core, GSSDP and GUPnP itself) will see a 1.0 release together with the next GNOME release. They are quite stable API-wise and functionality-wise now and I think it’s time to give them a proper blessing for that.

After that, master will become more unstable in regards of API, as there are some long-standing bugs and fixes that need an API change as well as new features to be added, such as proper IPv6 support, support for more recent versions of the UPnP standard (UDA 1.1, UDA 2.0), a more GIO-like async API,…


We’ve been digging up some annoying age-old bugs or regressions deep down in Rygel for some corner-cases (Did you know that renderer unmute was broken since 2013?)


Some more usability fixes on their way, but the big roadblock of RAW import performance is still proving to be quite annoying. Bit like a hydra, really. You cut of one RAW developer, three new seem to disappear.

Project Lazarus: GtkTerm

I took GtkTerm and poked a bit at its source, mainly for two reasons

  • Dry-run some GTK modernisation that will be necessary in Shotwell as well (GAction etc.)
  • It’s the least worst (sic) of the graphical serial terminals I tried. At least it seems to cope way better with odd USB <-> Serial adapters than t rest of the bunch
  • I use it

Ok, that’s three reasons.

If you want to have a look, head over to its repository at


  • Rygel is currently mainly receiving maintenance things because reason. This is hopefully changing soonish
  • I picked up Shotwell as maintainer and things are coming along nicely, though its architecture sometimes makes changes that sound really easy very hard (e.g. certain import performance improvements). Most annoying part, though, is that the merging of the awesome map feature is somewhat affected by the recent woes regarding MapQuest’s tile server
  • I’m going to be at GUADEC during its core days

That’s all for now.

Rygel updates

This is going to be a bit longer than usual. I’m going to present some of the changed that have gone into Rygel since the last post (Wow, over a year ago…, sorry about that)

Inner changes

After 0.24, Rygel has received a new internal resource handling that basically decouples the UPnP item from a file so that – in theory – an UPnP item can have multiple on-disk resources.

Unfortunately, this code was contributed as a big lump of code; I tried to split it up and make it more manageable, but the result was that the 0.26 series of Rygel has had several regressions, sorry about that. The 0.28.3 stable release should be as good as the 0.24 release.

New features

Access control

Rygel has gained support for a simple access control mechanism. It’s rather simple and checks whether access to an URI is allowed by a remote peer using DBus.

Unfortunately there is no “policy engine” yet. So from a user perspective, there is currently no difference. Implementing this is on the agenda for 0.32.

More robust

MediaExport’s meta-data extraction was made more robust by moving the extraction into its own process. Files that cause the extraction process to crash will be black-listed and never touched again. There is a new tool in the GIT that lets you investigate the database, the black-list and remove uris from that blacklist.

DVD support

With the upcoming stable release 0.30, Rygel’s MediaExport plugin will gain support for exposing DVD images, either as ISO files or as VIDEO_TS folders. Expect some rough edges; for example, many clients will not be able to seek in the video files as it requires some non-mandatory DLNA seeking features for now. Also DVDs with many titles are not really nice to navigate.

LightMediaScanner support

Rygel has gained support for exposing the contents of LightMediaScanner’s media index.

Request for support

The UPnP forum has been merged with the OCF. Unfortunately, this means that there is no longer a free membership available with access to the certification tools. There is a new non-profit membership which even allows for certification, but it costs $1000. While I’m willing to pay a large chunk of that myself, it would be awesome if some people would join me in making this happen for Rygel and GUPnP sooner. It would allow me to get them more compliant, tested (e.g. for IPv6 support) and maybe even UPnP certified. I would like to setup some crowd funding thing for that, but I have no clue which platform I should use. Is there any site that doesn’t upset RMS?

That’s all for now.

Things ‘n’ stuff

Long time no blog. Sorry about that. Things have gotten a bit busy since I changed jobs in Nov 2013, moving along to the crazy and sometimes insane world of automotive in general and IVI in special. Due to that and a rather unpleasant commute, things in Rygel land have gotten a tad more silent then I hoped, not revolutionary, maybe not even evolutionary. For example, there’s still no ACL support as I promised way back on GNOME.Asia 2013.

I will have to skip FOSDEM this year for several reasons, sorry about that.

For Rygel, I hope to finish the integration of (most of) Cablelab’s changes for their CVP-2 work as they will allow nice and long requested features such as pre-transcoding or transcode caching, server-side trickmodes, simple device-dependent resource reorder (for devices that are too stupid to pick the proper resource). Unfortunately I have found a rather large feature regression with upload that seems to turn out to be somewhat nasty to fix.

That’s all for now.

About a decade too late…

I’m currently working on adding DVD sharing to Rygel and while doing that, I resurrected a tool I wrote in 2005 to aid the tedious process of authoring DVDs on Linux. Today I cleaned it up a bit, gitified it and pushed it to github:

Please be warned that it might kill your data if you don’t read the message boxes carefully and cancel in time (and I mean that seriously, not as a standard disclaimer).

Raspberries and Rygel

First I have to apologize for the delay. I initially announced this in my GNOME.Asia talk almost two months ago.


Raspbian and hardware-accelerated video decoding in Rygel without X. Follow brief instructions on

What’s this problem?

There are already several solutions in the wild that combine Rygel and the Rasbperry Pi, be it Guacamayo or stock Raspbian. While Guacamayo provides easy server and audio renderer images, none of the existing solutions provide a video renderer.

Why’s that? Well, the RPi is (intentionally) slightly underpowered to do video decoding on the CPU. Howerver, it supports video decoding in hardware.

The issue here is that Raspbian is based on wheezy which only comes with GStreamer 0.10 while the support for hardware-based video decoding on the RPi in gstreamer-omx was only added recently to GStreamer 1.0.x. And since this is wheezy, the Rygel package that comes with it is too old to use GStreamer 1.0.

So let’s just grab the packages from sid armhf, should be working, no?

No it doesn’t. Rasbpian is basically a recompilation of Debian for ARMv5 with hard float ABI, while Debian itself is using ARMv7. So we can’t just copy packages.


Well the good news is that we don’t need to do all the heavy recompiling of GStreamer. Someone already did that for us. This work is available at (from the forum).

And what exactly are you doing now?

We provide a Debian repository with Rygel’s packages backported to Raspbian. That’s a bit boring, you say? Indeed. This is only the beginning. There will also be a set of instructions to convert a Rasbian installation into a hardware-accelerated DLNA renderer. The first step to this is a meta-package called raspbian-dlna-renderer which depends on all the other important packages necessary for a complete environment.

What’s working right now?

First, add the following repositories to your /etc/apt/sources.list

deb wheezy/
deb-src wheezy/

deb . main

The packages on are signed with my private GPG key, key id 7696ECBF. Then run apt-get update && apt-get install raspbian-dlna-renderer to get all updated and necessary packages.

I’ve modified /boot/cmdline.txt to get a screen that is as empty as possible by adding silent and logo.nologo to the kernel parameters.

You can then launch Rygel as user and play files on the RPi using Helium, gupnp-av-cp from GUPnP Tools or any other DLNA control point.

What’s next?

A next version of the meta-package will probably add auto-starting Rygel as a system service – Maybe we’ll even provide a ready-to-go image…