[asterisk-bugs] [Asterisk 0012367]: Codec negotiation failure

[noreply at bugs.digium.com]

A NOTE has been added to this issue. 
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http://bugs.digium.com/view.php?id=12367 
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Reported By:                mascool
Assigned To:                
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Project:                    Asterisk
Issue ID:                   12367
Category:                   Channels/chan_sip/CodecHandling
Reproducibility:            always
Severity:                   minor
Priority:                   normal
Status:                     new
Asterisk Version:           1.4.18 
SVN Branch (only for SVN checkouts, not tarball releases): N/A 
SVN Revision (number only!):  
Disclaimer on File?:        N/A 
Request Review:              
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Date Submitted:             04-03-2008 21:33 CDT
Last Modified:              04-06-2008 16:28 CDT
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Summary:                    Codec negotiation failure
Description: 
I have a provider that supports both ulaw and g729. Provider set to allowed
ulaw and g729 (in that order). Aastra phone set to use G729 only. Call
fails with "No audio format found to offer" even though it should be ok
based on this line:

Capabilities: us - 0x104 (ulaw|g729), peer - audio=0x105
(g723|ulaw|g729)/video=0x0 (nothing), combined - 0x104 (ulaw|g729)

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---------------------------------------------------------------------- 
 flefoll - 04-06-08 16:28  
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>Why would I need the g729 codec? If both the provider and the second leg
support
> g729, shouldn't asterisk let g729 pass through?

You are right, depending on your Dial() options, Asterisk may, or may not,
need to decode g729, or just let it pass through.
But if you have one leg ulaw and the other g729, then it need to. If you
want to use g729 on both legs, in order to avoid codecs translation, it
seems better to define g729 as prefered choice for both parts, and then it
succeeds as you say in your note. 

Issue History 
Date Modified   Username       Field                    Change               
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04-06-08 16:28  flefoll        Note Added: 0085060                          
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