Using AudioDataOutput unsynchronized

[Sergey Vlasov]

Hello,

I'm developing a small audio application and I use Phonon as its backend for
playback and more. I want to draw audio graph (waveform) of the file and I
need to access to raw PCM audio samples. I can do that with
Phonon::AudioDataOutput but I have two problems.

First, it doesn't emit dataReady() signal unless I create an extra path from
it to Phonon::AudioOutput. Why is there such a limitation? Especially when
playback gets so unacceptably full of pops and clicks. AudioDataOutput is
not supposed to be used to alter audio data during playback (isn't
Phonon::Effect for that?). If it's meant to be used for visualizing purpose
only then why to put it in between of MediaObject and AudioOutput and thus
cause huge glitches due to overhead?

Second, how can I make it to output audio data full speed that is
asynchronously and without output to sound card? That would solve the first
problem too.

I guess that's just a bad design for AudioDataOutput and it's not going to
change. So I wonder if someone out there knows of some unofficial Phonon
class or a patch to AudioDataOutput that could allow me to do that? I'm
aware of QtMultimedia but it works only with wave files while with Phonon I
can read pretty much any audio format.

--
Sergey
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