[jitsi-users] Stuttering audio calls on Windows 7 x64


#1

snipped a bit here
question at the far end

I installed the latest nightly and it seems is better.
If I use WASAPI the audio call is not stuttering now (the latest stable
version is 5 months old and I suppose you did many improvements).

Indeed, we improved the audio quality and stability in major ways by
replacing PortAudio with WASAPI as the default audio system.

But the noise suppression function is doing poor job on noise reduction.

Well, Windows is doing the synchronization between the capture and the
playback for the purposes of the acoustic echo cancellation (AEC).
Anyway, (1) it's working perfectly for us and (2) it's unquestionably
far better than what we had with PortAudio and Speex.

Anyway, still more usable than before.
If I activate PortAudio the stuttering is here again. My experiments and
observations lead me to believe I was right - maybe the sound buffers are
too small, and Jitsi fails to set the system timer resolution. By default it
is 15.6ms in one of the systems in the conversation and it stutters bad.
However if I use TimerResolution.exe tool and set to 0.5ms then the call is
Ok with occasional stuttering but Much less frequent.

Still I think there is a problem with the audio buffers and/or failing to
work on the timer resolution on Windows - any music player lowers the
resolution from 15 to at least 1ms when playing sounds.

By the way, is there any side effects of using WASAPI rather than the
PortAudio choice? PortAudio was the default in the stable, now I see the
default is WASAPI after I installed the nightly.

We are moving away from PortAudio because it has multiple performance
and stability issues. Windows Audio Session API (WASAPI) is what we
expect our users on Windows Vista+ to use. So in the terms of your
question, the side effects should be that the audio should exhibit
better quality and stability.

as this (WASAPI) and video conferncing in general is new to me, I am also experince the stuttering in the audio by using the stable on XP. Mentioned above, to use WASAPI with Windows Vista+, is WASAPI available for XP also ? As I said, it's new to me, so propably a stupid question.

If this could be clearified, I also would try to use the last nightly version.

Thank you
Johannes

···

On Sun, 25 Aug 2013 19:59:29 +0300, Lyubomir Marinov <lyubomir.marinov@jitsi.org> wrote:

_______________________________________________________
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Johannes Prost


#2

Microsoft have introduced Windows Audio Session API (WASAPI) in
Windows Vista and have not backported it to Windows XP so,
unfrotunately, Jitsi is stuck with PortAudio on Windows XP.

Theoretically, we could use DirectSound to replace PortAudio on
Windows XP. In practice, we are unlikely to invest into such an
effort.

···

2013/8/25 Johannes Prost <Johannes@yorktondigital.ca>:

as this (WASAPI) and video conferncing in general is new to me, I am also experince the stuttering in the audio by using the stable on XP. Mentioned above, to use WASAPI with Windows Vista+, is WASAPI available for XP also ? As I said, it's new to me, so propably a stupid question.