[music-dsp] Musical signal AGC (compressor..normalizer)
flashinc at mail.ru
Wed Jan 14 15:21:42 EST 2004
>> I tried to program Automatic Gain Control
>> Can anyone suggest me better technique than I used?
RB> Hi Alex:
RB> That's for a lookahead limiter.
Thanx for a link.
Really he does src signal Z delay line, not lookahead.
The paper is very basic, I myself to hit upon an ideas described in
this paper, because if one is patient enough to closely examine
matlab`s plots, he come to a conclusion
that envelope is slightly lags (phase shift)
and attack/delays behaviour should be improved in adaptive manner.. ;-)
I not a person who don`t realise such techniques, I am person who like
a details :-)
RB> But if you want to level whole tracks perhaps you should do a global RMS
RB> scan on each file and normalize each track according to average level rather
RB> than using a time-varying algorithm.
CoolEdit does same thing.
RB> Best wishes
Seems for me, that dumb RMS for 50 ms look-ahead buffer without
filter does better work than any combination of power estimator +
filter(smoother), because RMS is already does mean/averaging along look-ahead area.
I would test it using running summ RMS.
State of the Art!
Flash inc. Alex Raider
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