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A good idea, Kevin. You may also want to include additional performance parameters, such as the number of taps for the EC.<br><br>Gideon<br><br><br>> Date: Wed, 18 Jun 2008 18:11:06 -0500<br>> From: kpfleming@digium.com<br>> To: asterisk-dev@lists.digium.com<br>> Subject: [asterisk-dev] RFC: DAHDI echo canceller configuration change<br>> <br>> I'm working in a branch of DAHDI's 'linux' package:<br>> <br>> http://svn.digium.com/svn/dahdi/linux/team/kpfleming/modular_ec<br>> <br>> This branch contains modifications to allow one (or many) echo cancelers<br>> to be built and loaded at the same time, and then runtime selection made<br>> as to which one should be used on which channel(s). All of the existing<br>> modules have been converted, and the core code is ready to use them, so<br>> what I'm left with is deciding on a configuration method.<br>> <br>> I'd like to just use the existing /etc/dahdi.conf and dahdi_cfg tools to<br>> do the configuration, adding something like:<br>> <br>> echocanceler=MG2<br>> <br>> or<br>> <br>> echocanceler=HPEC<br>> <br>> Doing so would then apply that choice to all subsequent channels<br>> configured in the file in *any* signaling mode (although obviously many<br>> signaling modes don't support audio, and thus will never actually use<br>> the echo canceler defined for those channels).<br>> <br>> This seems pretty straightforward to me, however, it would be the *only*<br>> parameter in /etc/dahdi.conf that 'inherits' into later definitions in<br>> the file, which is probably not a wise choice.<br>> <br>> An alternative would be for the syntax to be something like:<br>> <br>> echocanceler=MG2,1-4<br>> echocanceler=HPEC,8-12<br>> <br>> This fits the existing model a bit more.<br>> <br>> In addition to this, there is a need to find some way to set a default<br>> echo canceler to be used if the configuration file does not specify one.<br>> In Zaptel, this was done at compile time, but since all available echo<br>> cancelers are compiled and installed now, there isn't any practical way<br>> to do that, and I'd rather move away from compile-time configuration anyway.<br>> <br>> I could certainly add an additional configuration parameter for this, or<br>> make the 'echocanceler=<name>,<channels>' parameter accept *no channels*<br>> as an argument, which would then apply it to all channels.<br>> <br>> Thoughts? Whichever way this goes, I'll end up documenting it in<br>> UPGRADE.txt in the source tree, because it will be a significant change<br>> in behavior from Zaptel 1.4.<br>> <br>> Another note: I won't require the user to forcibly load echo canceler<br>> modules; if a name is provided and no module currently provides it, the<br>> DAHDI core will attempt to 'autoload' that module to satisfy the request.<br>> <br>> -- <br>> Kevin P. Fleming<br>> Director of Software Technologies<br>> Digium, Inc. - "The Genuine Asterisk Experience" (TM)<br>> <br>> _______________________________________________<br>> --Bandwidth and Colocation Provided by http://www.api-digital.com--<br>> <br>> AstriCon 2008 - September 22 - 25 Phoenix, Arizona<br>> Register Now: http://www.astricon.net<br>> <br>> asterisk-dev mailing list<br>> To UNSUBSCRIBE or update options visit:<br>> http://lists.digium.com/mailman/listinfo/asterisk-dev<br><br /><hr /> <a href='' target='_new'></a></body>
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