Re: [Linphone-developers] VAD for Speaker and Mic

[Simon Morlat]

Hi,

You should consider first upgrading to 3.2.x since the echo limiter has been 
improved a lot in this version.
Then add to your linphonerc, in [sound]
echolimiter=1

There are other optional parameters
el_speed=0.03 (controls the speed of the gain correction)
el_thres=0.1 (controls the speaker volume threshold above which the system 
becomes active)
el_force=5 (controls the force of the attenuation of the mic channel, 
proportional to the power of the speaker signal)
el_sustain=200 (in milliseconds, controls how much time the attenuation 
remains active after resuming from speech, useful to take in account latency 
in soundcard processing).

Simon

Le vendredi 2 octobre 2009 09:02:00, Aurelien Bouin a écrit :
> Hello,
> I am currently working on a device that have a loud speaker(2 Watts) and a
>  microphone really close to the speaker, it is based on an ARM iMX27
>  platform that embed linphone 3.1.2(currently) and works with an ffmpeg
>  that uses hardware for video codecs... I am really interested in using the
>  VAD that is implemented in linphone(msvolume), but i really don't know how
>  to tune it to work correctly with our devices, What I did is changed
>  completely the msvolume to use a halfduplex mode, I could commit our
>  implementation If you are interested, but I am still interested in your
>  solution ...what could be even better is to be able to chose among
>  different audio treatment that could be implemented . . . thank you in
>  advance for your time,
> Sincerely,
> 
> Aurelien BOUIN
> 
> > Do you know since what version of linphone has this feature been
> > available?
> 
> since 3.2.0 (lastest)
> 
> > Eric
> >
> > On Wed, Sep 30, 2009 at 8:31 AM, Simon Morlat <address@hidden>
> 
> wrote:
> > > Hi,
> > >
> > > This functionality is already implemented, it is called "echo limiter".
> > > In [sound] section of linphonerc, add echolimiter=1 to enable it.
> > > It's useful in cases where echo canceler cannot work (for various
> > > reasons). It 's  implemented in mediastreamer2/src/msvolume.c
> > > and driven by coreapi/linphonecore.c, within
> > > linphone_core_start_media_streams()
> > >
> > > Simon
> > >
> > > Le mardi 29 septembre 2009 20:38:43, Eric des Courtis a écrit :
> > >> Hello,
> > >>
> > >> I would like the run linphone with a loud speaker and a mic. I don't
> > >> want feedback from the speaker into the mic. I was wondering if there
> > >> is a mechanism to detect incoming audio (from the rtp stream) and to
> > >> mute the mic during that time to prevent feedback? If not can anyone
> > >> give me pointers on what would need to be done in order to accomplish
> > >> this?
> > >>
> > >> Cheers.
> > >>
> > >> Eric des Courtis
> > >>
> > >>
> > >> _______________________________________________
> > >> Linphone-developers mailing list
> > >> address@hidden
> > >> http://lists.nongnu.org/mailman/listinfo/linphone-developers
> 
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