Using MELP with Asterisk


#1

Hi everyone,

I’m new to * and I’d like to be able to use the MELP codec with it. I don’t know if this could be easily done or if it would need fiddling with the code. The only mention to MELP+Asterisk I’ve found for the moment is the following thread in the asterisk-dev list: lists.digium.com/pipermail/aster … 07502.html

I’m also looking for a softphone that supports MELP. Or, maybe, an open source one that lets me mess about with the code to try and make it support MELP.

Can someone give me any clues or point me to any resources that could be of help?

Thanks in advance.


#2

Do you have any links to MELP? First I have heard of this codec. Why is it special to you?


#3

A search in google will produce some results that will provide you with a basic description of the algorithm and, mainly, implementations by several companies.

It’s a US federal standard and what not, and quoting from [1], “The MELP algorithm was jointly developed by Texas Instruments, Inc., Atlanta Signal Processors, Inc., and NSA”. You can find a description in [2]

[1] maya.arcon.com/ddvpc/index.html
[2] aspi.com/tech/specs/pdfs/melp.pdf

I think there are several implementations and versions but I’m not terribly knowledgeable in either two (Asterisk or MELP) so I might have not given you the best information out there.

It’s not that it’s special to me but I’ve heard that it’s the best codec for very low bitrates. That’s why I want to use it.