[asterisk-users] Choosing codecs

[Luca Bertoncello]

Zitat von A J Stiles <asterisk_list at earthshod.co.uk>:

Hi,

> GSM is the native codec used for calls to mobile phones; it uses lossy
> compression to achieve a low bit rate.
>
> A-law is the native codec used by physical exchanges on the land line network
> (PSTN and ISDN).  It is non-lossy.  It works by arranging the "steps" closer
> together near the zero line, and further apart away from it; so the  
> difference
> between the actual signal and the nearest digital representation is small in
> proportion to the signal.

Well, but for voice quality, which codec is better?
alaw or gsm?

Thanks
Luca Bertoncello
(lucabert at lucabert.de)