> Only volume normalisation can be done without re-encoding.
> This is not an Audacity problem, any sound editor will do the same. Try
> to use "normalize" program, that support both mp3 and ogg.
Actually, this isn't even true, either. The latest version of normalize is
0.7.6, and although it can adjust the volume of mp3s without re-encoding, it
still must decode oggs to wav, and the re-encode after normalization.
Normalize (by Chris Vaill) can be found here:
The next version of normalize is supposed to be able to normalize vorbis files
losslessly, but it's been a long time since the author has done any work on
the project at all.
And as far as channel duplication, sox can do it, but not with compressed
audio. Anyway, if you find a workable solution, we'd all like to hear about it.
Graham Mitchell - computer science teacher, Leander High School