[asterisk-users] Wideband (G722) MeetMe

[Michael Graves]

I'm told that Asterisks wideband capability is exclusively based upon
16 khz sampling. Higher sampling rates, like you might find with CELT,
are downsampled for mixing at 16 khz.

My guess is that not everyone will be happy with this, especially
vendors trumpeting codecs with higher sampling rates. To handle their
output will be more CPU intensive.

I'm not an Asterisk insider. I just listen closely when the real
insiders speak up ;-)

Michael

--Original Message Text---
From: Doken, Serhad
Date: Thu, 18 Jun 2009 14:15:42 -0700



Thanks Michael. I guess prior to 1.6.2, Asterisk was downgrading
streams to SLIN before mixing and then mixed stream got upgraded to WB.


  

My question is, with this release, is Asterisk converting WB codecs to
SLIN16 and mix them that way ? That seems to be the logical way to me
just wanted an insider expert to confirm/deny that. 

  

Is this the right list to ask that question/find the right contact
before I delve into the code knee deep ? 

  

Serhad Doken 

  

From: asterisk-users-bounces at lists.digium.com
[mailto:asterisk-users-bounces at lists.digium.com] On Behalf Of Michael
Graves
Sent: Thursday, June 18, 2009 6:14 AM
To: Asterisk Users Mailing List - Non-Commercial Discussion
Subject: Re: [asterisk-users] Wideband (G722) MeetMe 



  

--Original Message Text---
From: Doken, Serhad
Date: Wed, 17 Jun 2009 16:07:12 -0700



Hi, 

I wanted to follow up on this thread about WB support on the MeetMe
bridge that is in 1.6.2. Does it only work for G722 or any WB codec ? 

I am working with another 16k WB codec that I can transcode to 722 and
vice versa. I was curious if the 1.6.2 MeetMe bridge can also mix 722
with any other WB codec natively(without downscaling). 

Thanks, 

Serhad Doken 

While not an expert in Asterisk internal, it seems unlikely that
Asterisk is mixing signals in encoded space. It's most likely
converting the stream to slin for mixing then encoding back into
whatever is most appropriate for each end-point.

Michael 

--
Michael Graves
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http://blog.mgraves.org
o713-861-4005
c713-201-1262
sip:mgraves at mstvp.onsip.com
skype mjgraves
fwd 54245 



--
Michael Graves
mgraves<at>mstvp.com
http://blog.mgraves.org
o713-861-4005
c713-201-1262
sip:mgraves at mstvp.onsip.com
skype mjgraves
fwd 54245


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