On Thu, 23 Jun 2005, Klaus-Peter Junghanns wrote: > > > > Yes, that should be possible. But I don't think a channel driver (and > > > > each > > > > channel driver) should do that on its own. Software echo cancelling > > > > belongs in a common part of Asterisk. > > > > > > > I strongly agree. But asterisk doesn't seem to work this way. Zap channel > > > has > > > it's own echo cancel engine. Other channels don't. > > > This is so sad :-( > > > Why not implement a really common echo cancel api usable from any channel > > > ?? > > > > Exactly! > > I'm not familiar with the Asterisk API, but it could be some > > plugin like res_* ... > > > > Maybe this belongs to the Asterisk-Dev list. > > > > Armin > > I strongly disagree. :-) You dont want to do echo cancelation in > userspace. Especially not on a non-realtime operating system. > To make echo cancelation work it has to be as close to the line > interface as possible. Also the frames have to be as small > as possible. This rules out capi pretty much.
If you don't want echo-canceling in user-space, then neither Asterisk nor any chan_* plugin should do it. I don't know the zap channel code, but does the zap echo-cancel-code is inside a kernel module? If yes, then I have to disagree here. Something like 'playing' with audio-data is nothing the kernel should be concerned with. This belongs in user-space and if you need realtime, then you should use a realtime OS or use RT-scheduling. Just putting such a code into kernelspace is a bad idea. So the correct way is either the hardware supports it or the application knows what to do with the data received, like DTMF. Armin _______________________________________________ Asterisk-Users mailing list Asterisk-Users@lists.digium.com http://lists.digium.com/mailman/listinfo/asterisk-users To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
