[NBLUG/talk] sox ulaw to mp3

[Walter Hansen]

>> Hi Walter,
>>
>> ulaw is different enough that I'm not surprised some apps don't
>> understand it. You will probably need to do a sample rate conversion
>> to something more typical as an intermediate step - also you will get
>> the proper resolution since ulaw is compressed and you don't want it
>> to be treated as raw even if you get the sample rate to match.
>>
>> Cheerful regards,
>>
>> Bob
>
> I think I just did it. The problem was that it was retaining the 4bit
> sampling rate (not sure if that's the correct term). I managed to find
> someone else who had run into this on google. His solution was to write it
> as a .cdr file as an itermediate step and then convert the .cdr back to
> .wav. At that point it lost the 4bit sampling and went to a more normal
> 16bit sampling. I invoked lame to convert it to mp3 and volia they sound
> great. I really should experiment with converting directly from .cdr to
> .mp3 in sox. That may work just as well and eliminate one conversion/step.
>
> Using -V in sox was a godsend. I'm not sure why I didn't think to do that.
> It then tells you exactly what it's doing.

Nope eliminating steps doesn't work. It wants to be converted to wav, then
cdr, then wav, then mp3.