Amarok cannot play any audio files / phonon backend missing

[hugo-ribeiro (Hugo Ribeiro)]

After starting amarok, the program gives the following warning

Phonon claims it cannot play mp3 files. You may want to examine the installation of the backend that phonon uses.

In reality, amarok won't play any audio file (wav, ogg, etc... )

Starting amarok with debug options shows the following warnings

WARNING: bool Phonon::FactoryPrivate::createBackend() phonon backend plugin could not be loaded 
WARNING: bool Phonon::FactoryPrivate::createBackend() phonon backend plugin could not be loaded 
WARNING: bool Phonon::FactoryPrivate::createBackend() phonon backend plugin could not be loaded 
WARNING: bool Phonon::FactoryPrivate::createBackend() phonon backend plugin could not be loaded 
WARNING: Phonon::createPath: Cannot connect  Phonon::MediaObject ( no objectName ) to  Phonon::AudioOutput ( no objectName ). 
WARNING: bool Phonon::FactoryPrivate::createBackend() phonon backend plugin could not be loaded 
WARNING: bool Phonon::FactoryPrivate::createBackend() phonon backend plugin could not be loaded 
WARNING: bool Phonon::FactoryPrivate::createBackend() phonon backend plugin could not be loaded 

After searching in my system for "phonon", I couldn't find any phonon backend. Specially, there is no trace of phonon-qt7 or any other backend.

Since qt4-mac is now configured with -no-phonon and -no-phonon-backend, one would probably need to install the backend separately.

Can a port for phonon-qt7 be created? (Eventually, if it works it would be nice to also have phonon-vlc and phonon-gstreamer).

Should the backends eventually be variants of phonon itself?

[michaelld (Michael Dickens)]

I had wondered if this might be an issue. Let me look into creating some backends for phonon via what they provide. It would also be good to get the QT7 backend going again, but that's part of Qt4 and might be tricky.

[pixilla (Bradley Giesbrecht)]

Cc Me!

[pixilla (Bradley Giesbrecht)]

This is still an issue with amarok @2.6.0_0.

[macports@…]

Cc Me!

[hmeine (Hans Meine)]

Cc Me!

[hmeine (Hans Meine)]

I have installed qt4-mac and py27-pyqt4, but I cannot play videos with phonon, since I get the above error message about missing backend plugins.

/opt/local/share/qt4/plugins does not have a "phonon_backend" subdirectory, which I think it should. I have also installed the phonon port, but I am unsure which one of them should bring the backend (I think qt4-mac). Also, there does not seem to be any relevant variant or additional port (as for the database drivers) from what I can see?

Don't know whether that's interesting, but MeVisLab successfully compiles the qt7 backend on OS X; I have MeVisLab installed and it has /Applications/MeVisLab.app/Contents/PlugIns/phonon_backend/libphonon_qt7.dylib If you want to know more about MeVisLab's (qmake-based) build system, let me know (I am a MeVisLab developer).

[macports@…]

Cc Me!

[mkae (Marko Käning)]

Cc Me!

[desertshadow@…]

There is now what appears to be a backend port called phonon_backend_gstreamer, but it has an open bug at the time of this comment: #50049