Do you just want to adjust the loudness between multiple files?
(this means there is just a constant gain for every file so the they are
similar on average)
Or do you also want to change the loudness inside one track?
For case 1, you have to measure the loudness somehow (best way would be
to use a loudness standard like used in EBU R128 - see
and then you apply a constant gain, combined with a limiter (and maybe
compressor) if the gain is positive.
For case 2, it's more complex ;)
we build an audio processing webservice (http://auphonic.com), which
does both cases, for case 1 just use the "global loudness normalization"
algorithm, for case 2 use the "adaptive leveler" too!
For case 1 you could also use libebur128 (or some other tools) to
measure the loudness, then apply a gain and limiter somehow ...
Am 2012-10-05 18:30, schrieb Atte André Jensen:
auphonic - automatic audio post production
audio development, machine learning, open source and more
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