[Asterisk-Users] Re: IVR GSM voice prompt quality

[John Todd]

At 5:51 PM -0400 on 4/27/04, James H. Cloos Jr. wrote:
>  >>>>> "Steven" == Steven Critchfield <critch at basesys.com> writes:
>
>Steven> Conversion should be nothing more than sox orig.wav orig.gsm
>
>Are you sure they come as signed linear 8 kHz wav files?
>
>The uncompressed files John has on his site are 44.1 kHz PCM
>aiff files, so something more like this is required for optimal
>sound quality *if* that is how Allison records the files:
>
>sox file.aiff -c 1 -r 8000 file.gsm resample -ql
>
>-JimC
>--
>James H. Cloos, Jr. <cloos at jhcloos.com> <http://jhcloos.com>

Allison typically provides files in 44khz, 16 bit stereo .mp3's.   I 
just convert them into .aiff during my "hack and cut" sessions, and 
then run a batch file against them on my * host to convert into .gsm.

Here is the ugly hack I use for conversion:

#!/bin/sh

for file in *.aif
  do
         sox ${file} -r 8000 -c 1 `echo $file|cut -f 1 -d "."`.gsm
  done


JT