Use phonon from Qt or kdesupport?

Pau Garcia i Quiles pgquiles at
Tue Jul 21 12:49:35 BST 2009

On Tue, Jul 21, 2009 at 1:30 PM, Thiago Macieira<thiago at> wrote:
> Em Terça-feira 21 Julho 2009, às 12:15:06, Fathi Boudra escreveu:
>> On Sun, Jul 19, 2009 at 7:18 PM, Pierre Schmitz<pierre at> wrote:
>> > On the other hand some apps like kaffeine only work with xine
>> > backend. And because you cannot use different backends at the same time
>> > you have to switch it in systemsettings everytime you want to use for
>> > example Arora watching a video or kaffeine to watch TV. OK, I am going
>> > off topic here a bit...
>> not only arora or kaffeine, which are 3rd party applications atm, but
>> dragonplayer (kdemultimedia) also.
> Applications shouldn't depend on specific backend functionality. If they need
> something specific, add to the front-end API of Phonon and add to *all*
> backends.

Dependency on a specific backend is undesirable but some times it is
also a requirement.

For instance, if you want to play video coming from a RTSP source:
- the Xine backend cannot do that (it does not support non-seekable sources)
- the GStreamer backend is able to do that
- the DirectX backend is able to do that but it requires to install a
special codec and usually that special codec needs its own semantics
(for instance, if you use the RTSP codec Axis provides, you need to
use axhttprtsp:// instead of just rtsp://)

Another case: Camtasia-encoded videos:
- they don't work with the GStreamer backend because the codec is broken
- they work fine with the Xine backend, provided that you have
installed the win32 DLLs
- they work fine with DirectX, provided that you have installed the
Camtasia codec
(the same is true for FFV1 and FFVHUF, the ffmpeg lossless codecs)

So, in my case, I have an application which plays video from Axis
surveillance cameras and also has to be able to play Camtasia-encoded
videos (for training). Both at the same time. On Linux, this is not
possible: if I use the GStreamer backend, I cannot play
Camtasia-encoded videos. If I use the Xine backend, there's no
surveillance cameras. I have not tried the VLC or mplayer backends yet
but I'll be doing that next week.

It would be nice if we could specify backend preference for each
MediaSource. If that backend is not available, the next backend is

Pau Garcia i Quiles
(Due to my workload, I may need 10 days to answer)

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