DTMF generator doesn't seem to produce correct output?

[achaloyan]

Originally reported on Google Code with ID 107

I can't figure out why this patch isn't working. I can confirm mpf_dtmf_generator_put_frame
is successfully being called, but the MRCP server is not receiving DTMF event frames
(as seen in Wireshark).

http://jira.freeswitch.org/secure/attachment/13217/0003-Implement-mod_unimrcp-asr_feed_dtmf-by-generating-ou.patch
Related issue: http://jira.freeswitch.org/browse/FS-2907

Reported by luke@dashjr.org on 2010-12-08 14:31:30

[achaloyan]

Hi Luke and others,

briefly looking at the patch, everything seems correct. I can recommend few things
to try:

* If you can hear audio (speech), try to send the digits in-band, i.e. mpf_dtmf_generator_create_ex(stream,
MPF_DTMF_GENERATOR_INBAND, 500, 500, pool) and listen to the audio transmitted.
* Use mpf_dtmf_generator_sending() for generator's activity detection rather than mpf_dtmf_generator_put_frame(),
see the documentation in the header.
* AFAIK, out-of-band (RFC2833) digits are modified somehow inside MPF and I am not
sure how. Anyway, stream with payload type 101 must be properly set up for the digits
to be sent.

I hope this helps.

Cheers,
- Vali

Reported by tomas.valenta@speechtech.cz on 2010-12-15 09:58:57

[achaloyan]

Hi Luke,

I guess the problem is in the setup but not in the patch itself. To make out-of-band
DTMFs work, "telephone-event" should be properly negotiated through SDP offer/answer
model. In other words, make sure "telephone-event" is added to the codec list of FreeSWITCH's
MRCP profile you are using. For example,

   <param name="codecs" value="PCMU PCMA L16/96/8000 telephone-event/101/8000"/>

This is what I could guess for now. If it doesn't help, try to provide logs and corresponding
network capture as well.

Reported by achaloyan on 2011-01-03 21:41:28

• Labels added: Type-Defect, Priority-Medium, OpSys-All, Component-MPF, Component-FreeSWITCH

[achaloyan]

This bug is invalid, but I don't know how to close it.

Reported by luke@dashjr.org on 2011-01-26 20:43:50

[achaloyan]

Well, if everything works as intended, then let's mark this issues as verified.

Reported by achaloyan on 2011-02-02 20:23:57

• Status changed: Verified