Comments on: JACK interfaces for Asterisk

By: Jamie

Jamie — Fri, 01 Jan 2010 20:10:13 +0000

I have tried to find this function in both a Trixbox installation and AsteriskNow. Both installations are running Asterisk 1.6 and when I issue the command core show function JACK_HOOK NOTHING is there on either installation. I have spent the last couple of days looking for a possible solution with no avail. Anybody know of a module that I may be missing? According to what I read this is suppose to be a core function in Asterik 1.6.

By: sergio

sergio — Tue, 19 May 2009 14:59:44 +0000

Hi Russell, finally I’ve the delay between
different equipments (voip phones, softphones, jack interfaces and console using alsa and oss)

Voip to voip phone call has a delay of 40ms.
Softphone (sjphone or zoiper) to voip phone has a delay of 80ms.
Dialing to jack interfaces (JACK(i(playback_1))) or dialing to console (Dial(CONSOLE/alsa/1)) it takes same delay, about 250ms. I think the problem is due to asterisk architecture and not jack interfaces.
Thank you and good job,

Sergio

By: sergio

sergio — Tue, 12 May 2009 09:38:07 +0000

Thanks Russell.
Today I’ve done some test using softphones (zoiper, ekiga, sjphone) and voip terminals (siemens, 3com) and have note that delay using a voip terminals reduce to 260ms (I’m using audio editor software to record my voice and see delay). Anyway this time is not faster enough for paging system due to feedback.

Ummmm! As soon I can I will measure delay in “normal communication” between voip terminals (to see delay without Jack interfaces).

Keep you informed

Sergio

By: russell

russell — Mon, 11 May 2009 18:01:20 +0000

Thanks for the feedback, sergio.

I would expect some amount of delay, as there is some buffering between Asterisk and jack, but 500ms seems a bit high. I haven’t looked at this code in quite a while, though …

By: sergio

sergio — Mon, 11 May 2009 14:27:27 +0000

Hi russel. Finally I can test JACK application. Great job!!!! I was able to “map” extensions to output audio channels. Each extension is mapped to one channel left or right. Asterisk and Jack can make a powerful paging system.

But, I’ve note that there is a long delay between voip phone and output channel (around 500ms). Do you get same delay?
Thanks,

By: russell

russell — Wed, 29 Oct 2008 18:02:37 +0000

You can get it from Digium svn:

svn co http://svn.digium.com/svn/thirdparty/libresample/trunk

By: sergio

sergio — Mon, 27 Oct 2008 16:55:08 +0000

hi russell, I was trying to enable app_jack appication (menuconfig) but it requires resample library. Where is it?
thank you
(Debian Etch)

By: sprintf

sprintf — Fri, 10 Oct 2008 03:03:07 +0000

russell,

is the app_jack module available for asterisk 1.4? if not how can i achieve what app_jack does in asterisk 1.4?

it is for our place of worship to allow elederly and infirm worshippers to have a 2 way participation in meetings

many thanks

By: russell

russell — Thu, 07 Aug 2008 01:34:04 +0000

It is not possible to tell JACK_HOOK() to connect to more than one input and one output port. I’m honestly not a Jack expert, but it seems like you might be able to accomplish that by telling Asterisk to connect to one port, that in turns is connected to a number of things. Also, there is no problem with moving around what the channel is connected to. That is a feature of Jack itself, and not due to anything I have done.

I’m glad you enjoy the feature.

By: Chris K

Chris K — Wed, 06 Aug 2008 17:20:08 +0000

Russell, I’d just like to say that you are my hero for creating this functionality. I’m not a strong programmer and I am glad that modules like this exist that allow for me to get to the audio in a trivial manner. Under the current application, is it possible to tell Jack_hook to connect to more than one output, and is it okay to switch the output connection while the call is “jacked”?