[asterisk-bugs] [Asterisk 0010331]: [patch] PCMA/16000 and PCMU/16000 support (hd telephony)

[noreply at bugs.digium.com]

A NOTE has been added to this issue. 
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http://bugs.digium.com/view.php?id=10331 
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Reported By:                guido-r
Assigned To:                
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Project:                    Asterisk
Issue ID:                   10331
Category:                   Channels/chan_sip/CodecHandling
Reproducibility:            N/A
Severity:                   feature
Priority:                   normal
Status:                     new
Asterisk Version:           1.4.9  
SVN Branch (only for SVN checkouts, not tarball releases):  trunk 
SVN Revision (number only!): 77765 
Disclaimer on File?:        N/A 
Request Review:              
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Date Submitted:             07-30-2007 04:34 CDT
Last Modified:              08-08-2007 22:48 CDT
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Summary:                    [patch] PCMA/16000 and PCMU/16000 support (hd
telephony)
Description: 
With this patch PCMA/16000 and PCMU/16000 will be accepted during the SDP
negotiation. Prior asterisk ignored the sample rate in the rtpmap lines of
the SDP body and changed the 16000 to 8000.. and so the negotiation between
the UAs failed.
Now the sample rate is parsed too, and for now PCMA/16000 and PCMU/16000
are supported by the new option flag AST_OPT_16000.

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---------------------------------------------------------------------- 
 andrew - 08-08-07 22:48  
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You have to be careful about data rate vs. sample rate. G.722 has a sample
rate of 16Khz but a data rate (in RTP) of 8Khz (64kbit/sec)...also because
of the confusion G.722 is still listed as an 8Khz codec. Look at the RFC:

Section 4.5 lists sample rate at 16Khz:
http://tools.ietf.org/html/rfc3551#section-4.5

Section 4.5.2 says why 8Khz is still listed:
http://tools.ietf.org/html/rfc3551#section-4.5.2 

Issue History 
Date Modified   Username       Field                    Change               
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08-08-07 22:48  andrew         Note Added: 0068639                          
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