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Summary:ASTERISK-13174: [patch] Asterisk is using wrong clock frequency in text T140
Reporter:Christer (epicac)Labels:
Date Opened:2008-12-08 07:04:25.000-0600Date Closed:2009-04-14 12:46:04
Priority:MinorRegression?No
Status:Closed/CompleteComponents:Core/RTP
Versions:Frequency of
Occurrence
Related
Issues:
Environment:Attachments:( 0) timestamp.patch
Description:Timestamp in text T140 (RFC 4103) is wrong. Asterisk transmits it with a clock that runs 90000 ticks per second. In the SDP Asterisk declares that it uses 1000 ticks per second.

The problem originates from function ast_rtp_raw_write in rtp.c. The clock frequency for text is set to 90000 instead of 1000.
Probably this lines need to be changed and predictioncode for text needs to be removed:
"rtp->lastts = rtp->lastts + ms * 90;"

Edit: (inline patch removed by blitzrage)



****** ADDITIONAL INFORMATION ******

From rfc4103
" Timestamp:         The RTP Timestamp encodes the approximate instance
                     of entry of the primary text in the packet.  A
                     clock frequency of 1000 Hz MUST be used.
                     Sequential packets MUST NOT use the same
                     timestamp.  Because packets do not represent any
                     constant duration, the timestamp cannot be used to
                     directly infer packet loss."
Comments:By: Leif Madsen (lmadsen) 2008-12-08 09:32:54.000-0600

I've removed the inline patch from this bug as all patches need to be uploaded in order to go through the licensing process. Could you re-upload your patch to the tracker and submit a license disclaimer? Thanks!
By: Christer (epicac) 2008-12-08 10:14:06.000-0600

Resubmitting patch. I've signed license. Hope that's ok. :)
By: Leif Madsen (lmadsen) 2009-02-02 16:42:11.000-0600

Changing status to confirmed as the patch submitted here has a license! Thanks!
By: Digium Subversion (svnbot) 2009-04-14 12:40:51

Repository: asterisk
Revision: 188413

U   trunk/res/res_rtp_asterisk.c

------------------------------------------------------------------------
r188413 | file | 2009-04-14 12:40:51 -0500 (Tue, 14 Apr 2009) | 5 lines

Fix an incorrect clock rate when sending T140 text.

(closes issue ASTERISK-13174)
Reported by: epicac

------------------------------------------------------------------------

http://svn.digium.com/view/asterisk?view=rev&revision=188413
By: Digium Subversion (svnbot) 2009-04-14 12:42:12

Repository: asterisk
Revision: 188414

_U  branches/1.6.0/
U   branches/1.6.0/main/rtp.c

------------------------------------------------------------------------
r188414 | file | 2009-04-14 12:42:12 -0500 (Tue, 14 Apr 2009) | 12 lines

Merged revisions 188413 via svnmerge from
https://origsvn.digium.com/svn/asterisk/trunk

........
 r188413 | file | 2009-04-14 14:40:50 -0300 (Tue, 14 Apr 2009) | 5 lines
 
 Fix an incorrect clock rate when sending T140 text.
 
 (closes issue ASTERISK-13174)
 Reported by: epicac
........

------------------------------------------------------------------------

http://svn.digium.com/view/asterisk?view=rev&revision=188414
By: Digium Subversion (svnbot) 2009-04-14 12:43:20

Repository: asterisk
Revision: 188415

_U  branches/1.6.1/
U   branches/1.6.1/main/rtp.c

------------------------------------------------------------------------
r188415 | file | 2009-04-14 12:43:20 -0500 (Tue, 14 Apr 2009) | 12 lines

Merged revisions 188413 via svnmerge from
https://origsvn.digium.com/svn/asterisk/trunk

........
 r188413 | file | 2009-04-14 14:40:50 -0300 (Tue, 14 Apr 2009) | 5 lines
 
 Fix an incorrect clock rate when sending T140 text.
 
 (closes issue ASTERISK-13174)
 Reported by: epicac
........

------------------------------------------------------------------------

http://svn.digium.com/view/asterisk?view=rev&revision=188415
By: Digium Subversion (svnbot) 2009-04-14 12:46:04

Repository: asterisk
Revision: 188416

_U  branches/1.6.2/
U   branches/1.6.2/main/rtp.c

------------------------------------------------------------------------
r188416 | file | 2009-04-14 12:46:04 -0500 (Tue, 14 Apr 2009) | 12 lines

Merged revisions 188413 via svnmerge from
https://origsvn.digium.com/svn/asterisk/trunk

........
 r188413 | file | 2009-04-14 14:40:50 -0300 (Tue, 14 Apr 2009) | 5 lines
 
 Fix an incorrect clock rate when sending T140 text.
 
 (closes issue ASTERISK-13174)
 Reported by: epicac
........

------------------------------------------------------------------------

http://svn.digium.com/view/asterisk?view=rev&revision=188416