getting sox to use the amr-nb library?

[Adam Funk]

On 2009-07-08, David Fox wrote:

> On Tue, Jul 7, 2009 at 11:09 AM, Adam Funk<a24061 at ducksburg.com> wrote:
>
>> I have now (see below).  I checked and libsox-fmt-all is installed ---
>> although libamrnb3 isn't part of it but comes from Medibuntu.  Is it
>
> Where is the source of your ffmpeg? I assume it's a stock install from
> ubuntu, and not from medibuntu -in fact, apt-cache policy ffmpeg
> indicates that it comes from ubuntu directly.
>
> This brings up a possibility - get the original latest ffmpeg source
> from www.ffmpeg.org (or even svn) and compile it yourself, and set
> (--enable) the codec support you need. I don't know whether ffmpeg
> will support amr.
>
> I have a local svn repository here, initially installed for other
> unrelated reasons, but I haven't had a pressing need to keep it
> updated. I just reran svn up and now it won't comple :(.
>
> I think there are two other possibilities - inquiring directly on
> either the ffmpeg mailing list or the linux-audio mailing list. Their
> subscription addresses should be easy to find.

Your advice inspired me to do a bit more digging.  I discovered that
the amrnb package provides a command-line conversion tool, and this
sequence of commands worked:

amrnb-decoder Record001.amr Record001.sw
sox -r 8000 Record001.sw -c 2 -r 48000 Record001.wav resample
lame Record001.wav Record001.mp3

Thanks for the help.


(For the benefit of anyone searching the archive, this is how to
convert the files produced by a Nokia phone's "voice recorder"
function into some more sensible format.)