Megaconference

[Ben Fineman <>]

Hi Christian,

I'm not sure how to interpret your question but I can take it one of two ways, both of which are interesting points:

1) Why do the proprietary (non-H323) softclients do echo cancellation well, while standards-based clients struggle?

I would say this: echo cancellation is hard, and developing good echo cancellation is expensive. There is no good open source solution available, and from what I gather it must be prohibitively expensive to license the good solutions that are available. This means that solutions with good echo cancellation are either very mature ones that have been around for a while, or solutions that come from big players (with big $$$). In both cases this often means proprietary solutions - business models often hinge on the proliferation of a walled garden approach (such as Skype), while solutions that "do the right thing" and embrace interoperability have historically lacked the same level of financial backing. And of course from a technical standpoint, if you only have to support connections with your own client and proprietary format, many things (including echo cancellation) get easier. 

2) Why do softclients have better internal echo cancellation than room systems?

I disagree with this premise, but maybe this isn't what you meant. It is the case the room deployments often benefit from external echo cancellation technology, while you never see soft clients plugging into a big 1RU Biamp. The simple reason is that soft clients generally have to deal with a single microphone and speaker pair. This is much easier to echo cancel than, say, a conference room with eight ceiling speakers and eight table mics. Room codecs work very well with one (or even two, sometimes three) mics. But once you start to scale up to many mics and speakers you really need a dedicated external echo canceler.  

Let me know if I missed the point completely. 

Regards,

Ben

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On Dec 1, 2012, at 1:33 AM, Christian Helft <> wrote:

Hi,

Le 30 nov. 2012 à 23:15, "Simon Horne" <> a écrit :

2.       Recommend Headphones or echo cancelling speakerphone. (for everyone’s sanity)

Can you comment on the fact that any reasonably recent videoconferencing "softphone" (you name it: VSee, zoom.us, Jabber video, Messages (for Mac), Vid, etc. (even Skype)) doesn't require external echo cancellation any more, while there seems to be a malediction with truly H323 compliant systems?

Regards,

Christian.
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