Video suddenly lost

Ralph ralph.gucwa at
Wed Oct 10 07:44:21 PDT 2012

David Hoyt wrote
> GST_DEBUG is an environment variable and the library itself should be able
> to make use of it regardless of its execution environment (.NET, JVM,
> etc.).
> Try setting the environment variable on the command line, then execute
> your
> application from the same command prompt.

Fantastic!  I managed to get debug information from GStreamer!  Dave, you
are my hero :)

For those who would like to know how to get GStreamer debug from a Windows
C# application here's a short manual:

1. Modify your application to pass its command line arguments to GStreamer's
Init() method.  In WPF C# it looks like this:
            string assemblyName = Assembly.GetExecutingAssembly().FullName;
            string[] args = Environment.GetCommandLineArgs().Skip(1).Where(s
=> s.StartsWith("--")).ToArray();
            bool success = true;
                Gst.Application.InitCheck(assemblyName, ref args);
            catch (ApplicationException)
                success = false;
            if (success)
                //other initialization
In this example I'm only forwarding arguments beginning with "--", but you
can change it if you wish.

2. Create a batch file setting GST_DEBUG environment variable to a chosen
level and executing your application:
            set GST_DEBUG=*:2
            YourApplication.exe --enable-gst-debug=yes 2>gstreamer.log
where you should replace "*:2" with your desired debug level. 
"2>gstreamer.log" redirects stderr to a file.  "--enable-gst-debug=yes" is
passed to GStreamer using the modification from step 1.

3. Run the batch file...

And now back to my problem with the application not playing the video.
My audio pipeline looks like this:

gnlfilesource -> gnlcomposition -> audioconvert -> audioresample -> volume
-> autoaudiosink

For some reason autoaudiosink is not able to open the audio device:

0:00:13.765000000  5016   1021BC98 WARN                 default
error: gst_waveform_sink_prepare: waveOutOpen failed error=>A device ID has
been used that is out of range for your system.

This happens just on two computers, on dozens of other machines work my
program works fine.
Anyone knows why?

View this message in context:
Sent from the GStreamer-devel mailing list archive at

More information about the gstreamer-devel mailing list