[Asterisk-Users] Codec passthrough patch for IAX

[Jay Milk]

Hmm... What's the status of this?  This would allow me to declare one of
my incoming DIDs a fax-number by forcing it to use ulaw.

> -----Original Message-----
> From: Michael Giagnocavo [mailto:mgg at Atrevido.net] 
> Sent: Thursday, February 10, 2005 5:30 PM
> To: 'Asterisk Users Mailing List - Non-Commercial Discussion'
> Subject: [Asterisk-Users] Codec passthrough patch for IAX
> 
> 
> Hi there,
> 
> 	I had a problem, basically, I have 4 different types of 
> end users (gsm, ilbc, g729, ulaw). However, I only have one 
> user with my DID provider. My provider supports all 4 codecs. 
> The issue is then: When an incoming call comes in, a codec is 
> negotiated (usually ULAW), later on, when the extension is 
> dialed, we'll see we're doing GSM, and thus transcode. Here's 
> an example
> dialplan:
> 
> [incoming]
> exten => 123,1,Dial(IAX2/gsmUser)
> exten => 456,2,Dial(IAX2/ilbcUser)
> exten => 789,3,Dial(IAX2/g729User)
> 
> 	You're pretty much forced to accept ULAW, and then 
> transcode. Not fun if your provider does it for you (that's 
> what you pay them for, right?).
> 
> So, with this patch, just add a new config file.
> codec_passthrough.conf:
> [iax_my-did-provider]
> 123=gsm
> 456=ilbc
> 789=g729
> 
> 	Now, when an incoming call comes in, the user/extension 
> will be found, and your preferred codec changed. No more transcoding. 
> 
	http://bugs.digium.com/bug_view_page.php?bug_id=0003553

	My main question is: Can this be done without this patch? I've
heard it's impossible, and it sure seems that way. Any suggestions?