[asterisk-bugs] [Asterisk 0018934]: Recorded calls corrupted (GSM?)

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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https://issues.asterisk.org/view.php?id=18934 
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Reported By:                palmerv0r
Assigned To:                
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Project:                    Asterisk
Issue ID:                   18934
Category:                   Resources/res_monitor
Reproducibility:            sometimes
Severity:                   major
Priority:                   normal
Status:                     new
Asterisk Version:           Older 1.4 - please test a newer version 
JIRA:                        
Regression:                 No 
Reviewboard Link:            
SVN Branch (only for SVN checkouts, not tarball releases): N/A 
SVN Revision (number only!):  
Request Review:              
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Date Submitted:             2011-03-07 05:11 CST
Last Modified:              2011-03-07 06:26 CST
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Summary:                    Recorded calls corrupted (GSM?)
Description: 
We are using Asterisk 1.4.11 with several back-ported patches.  Our
customers sometimes report clicking noises and distortion with the
Monitor() application.  On inspecting the GSM .wav files which are
produced, the waveform goes through periods of being offset, with the
majority of the waveform appearing belong the centre line.
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 (0132685) davidw (reporter) - 2011-03-07 06:26
 https://issues.asterisk.org/view.php?id=18934#c132685 
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GSM doesn't encode a waveform; it encodes a model of the configuration of
the human vocal tract.  There may be some information related to the
original waverform, but it is not at all clear that it would cause the DC
offsets you describe.  My expectation for damaged GSM is that the decoding
codec would interpolate any seriously damaged parts. 

Issue History 
Date Modified    Username       Field                    Change               
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2011-03-07 06:26 davidw         Note Added: 0132685                          
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