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Record element with G711Alaw

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Hi all. I have not been able to find any relevant information or clear answers on if alaw is supported by CVP. I have tested it out and it seems to work
fine although i have one issue when it comes to the Voice - Recording element. Using ulaw the "beep" and recording workes just fine but when using alaw
the "beep" is not working and also not the recording. The error logs shows bad fetch. Dial-peers is set to alaw and all my other audio elements as well as playing prompts from ICM works just fine. Im using CUCCE 8.5 and CVP 8.5.
 
Could this be the limitation of CVP? Is the preferred codec ulaw for the Recording element and not possible to change it or what could be the issue here?
 

Patrik, from my understanding, 'codec g711ulaw' is what Cisco recommends.

Patrik,
You can record using different codecs depending on what the particluar gateway/IOS supports.  Are you saying that the Record element fails when you set g711alaw or that you don't know how to set it?

Hi Patrik,
 
Some brilliant folks in Australia (thanks Peter G and Greg S!) got the Recordings to be taken and stored using ALaw by doing the following:
 
1.In Studio's Record element to allow .wav files to be stored using
G711-alaw, configure these Settings:
File Type = other

MIME Type = audio/x-alaw-basic

 
 
2.On the Gateway:
voice class codec 10

 codec preference 1 g711alaw



dial-peer voice 31000 voip

 description CVP SIP Comprehensive dial-peer

 destination-pattern 89..

 session protocol sipv2

 session target ipv4:10.31.117.14

 voice-class codec 10

 no voice-class sip outbound-proxy

 dtmf-relay rtp-nte h245-signal h245-alphanumeric

 no vad

 

It's actually more flexible than that.  You just need to append the codec type onto the end of audio/wav in the MIME Type setting, for example, "audio/wav;codec=g711alaw" or "audio/wav;codec=g729br8".  If you want to do it dynamically then you can also retrieve the currently negotiated codec type (as in the attached doc) and append that dynamically to the MIME Type string.
Attachments:

Thanks Janine, did not know of that setting in Call studio element

Thank´s Paul for your answer, excellent document!