[asterisk-bugs] [Asterisk 0013405]: [patch] T38 gateway

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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https://issues.asterisk.org/view.php?id=13405 
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Reported By:                dafe_von_cetin
Assigned To:                
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Project:                    Asterisk
Issue ID:                   13405
Category:                   Applications/app_fax
Reproducibility:            N/A
Severity:                   feature
Priority:                   normal
Status:                     confirmed
Asterisk Version:           SVN 
JIRA:                       SWP-115 
Regression:                 No 
Reviewboard Link:           https://reviewboard.asterisk.org/r/459/ 
SVN Branch (only for SVN checkouts, not tarball releases):  trunk 
SVN Revision (number only!): 140548 
Request Review:              
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Date Submitted:             2008-08-30 16:44 CDT
Last Modified:              2010-03-07 17:01 CST
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Summary:                    [patch] T38 gateway
Description: 
Hi all,

I'm sending you patch containing new application app_faxgateway.c
("FaxGateway") which is able to mediate T30 to T38 and vice versa.
Feature is using spands library (I used spandsp-0.0.4pre18 and
spandsp-0.0.5pre4).

Best regards
Daniel.

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 (0119072) klaus3000 (reporter) - 2010-03-07 17:01
 https://issues.asterisk.org/view.php?id=13405#c119072 
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I now managed to have t38 gatewaying working for DAHDI->SIP. I also tried
SIP->SIP but it fails due to frame timing. Current sending of voice frames
is triggered by received voice frames - thus if the non-t38 client
(Asterisk using SendFAX) does not send RTP then the t38-gateway also does
not send voice frames.

I tried to modify the event loop to regularly check t38_gateway_tx() for
new voice data to send, but t38_gateway_tx() always responds with a full
voice-data bufer even it is called every ms.

So, does anybody know how t38_gateway_tx() works (no documentation :-()?

What is the preferred way to decouple frame generation from RTP reception
(I think the t38-gateway should send RTP every 20ms (or whatever the frame
rate is) also if it does not receive audio)? 

Issue History 
Date Modified    Username       Field                    Change               
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2010-03-07 17:01 klaus3000      Note Added: 0119072                          
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