Summary:ASTERISK-02737: [request] automatic disabling echo cancellation when data connection is on a call
Reporter:paradise (paradise)Labels:
Date Opened:2004-11-04 02:49:10.000-0600Date Closed:2008-01-15 15:12:43.000-0600
Versions:Frequency of
Environment:Attachments:( 0) zap_digital.diff
Description:as i know when echocancel=yes no modem data connection could be done on zap channels and when exhocancel=no possible echo will occur during a call.


this feature seems to be useful if * could detect data on a call and automatically disable echo cancellation on
**that call only**.  
something like "autoechooff" or "datadetect" parameter in zapata.conf.

Comments:By: paradise (paradise) 2004-11-04 02:56:02.000-0600

sorry! i'd better to assign the bug category to [Core Asterisk].

btw, this feature will make it possible to use a zap channel for
multi purposes [talking/fax/data] at the same time.

By: Brian West (bkw918) 2004-11-04 10:44:06.000-0600

Tjis is not true.. we shuttle fax calls over IAX to a fax box every day without fail.  And echo can is on.... makes me wonder how you have yours setup.


By: Paul Cadach (pcadach) 2004-11-04 10:53:43.000-0600

Attached patch is based on CVS-10/31/2004, so may be some outdated.

2Mark: this is the reason why I prints out line and function where echo cancelling is enabled. ;-)'

2bkw: fax is HALF DUPLEX, so echo cancellation is not plays bad roles in faxing. But for clean digital data (like zapras requires) echo cancellation MUST BE totally disabled to not disturb data going through a channel.

edited on: 11-04-04 10:54

By: Mark Spencer (markster) 2004-11-04 21:31:42.000-0600

I wish we could have it implemented with zt_enable_ec rather than have all the checks external.

By: Paul Cadach (pcadach) 2004-11-04 21:34:33.000-0600

There was a "quick hack" to bypass H320 IDSN video phone through Asterisk box. I'll check what could be done for moving checks to zt_enable_ec()...

By: Paul Cadach (pcadach) 2004-11-04 22:02:37.000-0600

Done for current CVS.

By: paradise (paradise) 2004-11-05 00:24:19.000-0600

from the patch:
 it seems that in some situations (maybe when data connection is established
 or on PRIs) on a zap channel a falg (p->digital) will be set.
so i just want to know:
 is this patch all i need?

edited on: 11-05-04 11:00

By: Paul Cadach (pcadach) 2004-11-05 10:43:42.000-0600

If (p or i in different places)->digital is set correctly - yes, this is only one to bypass digital connection without echo cancellation.

By: Mark Spencer (markster) 2004-11-07 01:29:43.000-0600

Do you have a disclaimer on file?  If you can confirm you do or can fax one as per the directions at http://bugs.digium.com we can go ahead and get this in.

By: Paul Cadach (pcadach) 2004-11-07 01:44:49.000-0600

Of course, I have disclaimer in the file.

By: Mark Spencer (markster) 2004-11-07 11:19:15.000-0600

Fixed in CVS.  Sorry I forgot you did the patch, pcadach and not paradise :)

By: Russell Bryant (russell) 2004-11-07 18:59:29.000-0600

not included in 1.0 for now ...

By: Digium Subversion (svnbot) 2008-01-15 15:12:43.000-0600

Repository: asterisk
Revision: 4170

U   trunk/asterisk.c
U   trunk/channel.c
U   trunk/channels/chan_zap.c
U   trunk/include/asterisk/channel.h
U   trunk/manager.c
U   trunk/res/res_agi.c

r4170 | markster | 2008-01-15 15:12:43 -0600 (Tue, 15 Jan 2008) | 2 lines

Disable echo canceller for digital calls (bug ASTERISK-2737), fix build on MacOSX (bug ASTERISK-2754)