[cisco-voip] How to play G729 audio prompt in a TCL IVR scrip

[Andrea Cerioli]

Hi all,
I fixed this problem.

Well the problem was trivial so I deserved no answers :)
However for the record, should anybody else run into this,
I can now state that IOS gateways do support many codecs
for IVR prompts, including G729.
The problem was the file format that was not playable from
the IOS gateway.
The file was produced on a CSICO CallManager using
the MOH file conversion utility.

It may sound strange, but  I needed an external tool (au_convert.exe)
to generate a properly encoded file, and get my audio prompts played by
the router.

I would have expected that WAV files produced with CISCO Call Manager,
using the MOH utility, would be compatible with IOS gateways, but this
is not the case.
Cisco IOS gateways cannot play that ("unsupported codec type").
I also tried to correct WAV fileds as decribed in "audio files support"
in the documentation, but this did not change anything.

So, what is (if any) the "supported" procedure to generate audio files,
using different codecs, to be played by the router?

Thanks for any answer.

Ciao.




> 
> Hi there,
> 
> we are tring to use a TCL IVR on a SIP call leg.
> Everithing works fine if we use G711ULAW or G711ALAW.
> When we try to use G729 we get:
> Aug 25 10:33:46.143: %IVR_MSB-3-NOPROMPT: Could not create IVR prompt
>  flash:test_codec.g729-corrected.wav
>  errno=0=Unsupported codec type
> 
> Some background follows to increase clarity:
> 
> AFAIK the IVR system match the codec negotiated for the SIP  call leg,
> with the encoding in the WAV header  of the audio file.
> If the match is successful, the audio prompt is played back,
> otherwise it fails.
> From CISCO DOCs and form TAC it looks like ANY codec is supported.
> Thus we produced our audio files, correcting them with an hex editor as 
> described
> in cisco Documentation:
> http://www.cisco.com/en/US/products/sw/iosswrel/ps1839/products_feature_guide_chapter09186a00800b5ddb.html
> 
> All works fine if we use G711A or G711U.
> We double checked by using the wrong file or wrong codec to make it fail.
> It only works when they match, and works for both codecs.
> 
> For G729 it always fail with the error above.
> 
> Thus I wonder if we are trying to do something unsupported.
> Maybe we need to use VXML instead of TCL to make it work? Do we need an 
> XML header?
> If yes, will a mixed language application work? (i.e. using a VXML 
> utility in the main TCL script to play
> the audio prompt and collect DTMF ...)
> 
> Thanks for your help.
> 
> Andrea.
> 
> -- 
> | Andrea Cerioli               alter.net Srl              |
> | e-mail: cerioli at alter.it     Via Attilio Ambrosini, 177 |
> | VOICE: +39-6-5405740         I-00147 Rome               |
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>