[asterisk-bugs] [Asterisk 0017235]: [patch] asterisk dsp always reports detected DTMF length to be 0ms

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
====================================================================== 
https://issues.asterisk.org/view.php?id=17235 
====================================================================== 
Reported By:                frawd
Assigned To:                
====================================================================== 
Project:                    Asterisk
Issue ID:                   17235
Category:                   Core/General
Reproducibility:            always
Severity:                   trivial
Priority:                   normal
Status:                     ready for testing
Asterisk Version:           1.6.2.7-rc2 
JIRA:                       SWP-1337 
Regression:                 No 
Reviewboard Link:            
SVN Branch (only for SVN checkouts, not tarball releases): N/A 
SVN Revision (number only!):  
Request Review:              
====================================================================== 
Date Submitted:             2010-04-23 10:21 CDT
Last Modified:              2010-04-29 17:52 CDT
====================================================================== 
Summary:                    [patch] asterisk dsp always reports detected DTMF
length to be 0ms
Description: 
The attached patch makes the DSP report the correct length for DTMF
detected in the audio.

Tested with DAHDI channels (FXS, FXO, ISDN PRI) and SIP channels
configured as "inband".
====================================================================== 

---------------------------------------------------------------------- 
 (0121189) frawd (reporter) - 2010-04-29 17:52
 https://issues.asterisk.org/view.php?id=17235#c121189 
---------------------------------------------------------------------- 
Thanks for the comments, would the attached patch be the right idea?

It's for 1.6.2, I quickly tested and it reports some length which I
believe is a bit closer to reality compared to the last one.

If dtmf are detected by blocks of 102 samples, it means we will always
have multiples of 12.75ms (rounded). I'm not sure if I can plug that in
deeper than dtmf_detect (in goertzel functions?) somehow to improve the
resolution to 1 sample as I understand you suggested. Are you sure it can
be done? 

Issue History 
Date Modified    Username       Field                    Change               
====================================================================== 
2010-04-29 17:52 frawd          Note Added: 0121189                          
======================================================================