Help getting experimental phonon work

Miguel José Álvarez Prieto mjalvarez at
Fri Jun 11 14:50:27 BST 2010

Hi, I am trying to develop an application to process video while it is being
played. I mean, process frame by frame before its presentation using the
gpu. Something very similar to what quasar does. I have donwloaded quasar
source code and built it without problems, but I can not get it to work,
neither my own code.
The problem is that when I try to connect a MediaObject source with the
AbstractVideoOutput sink with createPath, I got the message:

WARNING: Phonon::createPath: Cannot connect  Phonon::MediaObject (
mediaObject ) to  QObject ( abstractVideoOutput ).

The message in the phonon quasar example is:

WARNING: Phonon::createPath: Cannot connect Phonon::MediaObject ( no
objectName ) to Quasar::PhononInputNode ( no objectName ).

Phonon is working fine for normal video playback using a VideoWidget. This
is happening with the xine and gstreamer backends using the phonon 4.4.1
packages that comes with fedora core 13.

If I build phonon from source code (version 4.4.1 or 4.4.2), any application
that uses phonon chrashes wit a segfault. Is there any guide about how to
build a new version of phonon and get it working? That would be very helpful
for debugging and try to figure out what is happening before asking for

Any help on how to solve the problem mentioned above or how to correctly
build and get working a new version of phonon would be very appreciated.
These are my first steps developing with kde technology, I am very excited
about it and hope one day I will can contribute.

Thanks a lot and sorry for my bad english.

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <>
-------------- next part --------------
kde-multimedia mailing list
kde-multimedia at

More information about the kde-multimedia mailing list