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Re: [LUG] CD Quality VoIP?

 

On Fri, 30 Jan 2009, Dave Walker wrote:

> Rob Beard wrote:
>> On 30/01/2009 18:07, Dave Foxcroft wrote:
>>
>>> I have just read about Freeswitch implementing a new codec (CELT) that
>>> promises near CD quality voice using 48 kbps  (Freeswitch website for
>>> info - *http://tinyurl.com/3m3c8f *) - I'm not adocating the use of
>>> Freeswitch  - I use asterisk myself and have never used Freeswitch - has
>>> anyone else?
>>>
>>> It seems it is still considered experimental but if it lives up to the
>>> claims made then it may mean a lot more to VoIP than low cost calls!
>>>
>>> <SNIP>
>> I heard about that in this month's Linux Format which arrived today.
>> Presumably with the codec being open source it could be implemented on
>> Asterisk too if someone did the work?
>>
>> Rob
>>
> Hi,
>
> Which is great! Except no handsets yet support CELT, so you'll have to
> transcode locally to a mainstream codec such as G711 (uLaw/aLaw),until
> handsets support this.  Sadly, unless some of the larger proprietary PBX
> offerings provide this codec, it's unlikely to happen anytime soon.
> Handset manufactures are only just starting to tweak towards Asterisk
> settings, let alone publicly  'support' it.

G722 is this thing to look for if you want more than "telephone" quality, 
and asterisk is getting/has support for it.

However, when a call has to traverse the PSTN, it's always going to be 
transcoded into G711 or worse, so personally, I'm not convinced there's a 
place for it, and as long as I have customers who think G729 is 
"brilliant" I'm not in a hurry to look for something new...

I know people who can't tell the difference between GSM and normal 
phones...


Gordon

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