[asterisk-dev] Storing Voicemail messages in multiple formats ...

[Steve Edwards]

On Thu, 17 Jan 2008, sushma gupta wrote:

> I am trying to port the asterisk voicemail in an embedded linux
> environment.  I want to store the voicemessages in 3 formats (G726, ALAW,
> ULAW and possibly G729 in future).  This option is available in the Asterisk
> voicemail, however I want to store the message in any one of the above
> format(in a file) and transcode or convert in to other formats i.e. to other
> files at a later stage due to MIPS constraints.  Hence below are the
> question and I will much grateful if u can answer my below questions:
>
> 1.  How to go a head with this i.e. converting one file in to other files of
> different formats?

Since you are concerned with CPU horsepower, record in a single less 
resource intensive format like ulaw. Then, after the fact, use sox at a 
low priority and maybe after hours to convert to other formats. Someone a 
bit back on the list recorded messages on an NFS share and transcoded on 
another CPU that mounted the same share.

> 2.  I see in the conversion/transcoding is done at the time of recording, so
> I want to schedule a idle thread to do the conversion, in this case how can
> I convert from like alaw <=> ulaw,  alaw<=>G726, alaw <=>G729 etc
> combinations.

I would advise against this unless you already a skilled Asterisk 
developer.

Thanks in advance,
------------------------------------------------------------------------
Steve Edwards      sedwards at sedwards.com      Voice: +1-760-468-3867 PST
Newline                                             Fax: +1-760-731-3000