[sdiy] what is the amplitude envelope of a signal

[Ian Fritz]

At 07:02 AM 9/29/2003, Scott Bernardi wrote:
>How about an interpolation between the peaks of a rectified signal?

That's OK if you have just one peak  per cycle.  But if you have more, 
there could be big problems.  Think of the waveform you get if you excite a 
hi-Q filter with a narrow pulse.  This is not too extreme an example -- a 
bassoon give similar effects.

In general the envelope extraction problem is pretty difficult -- 
expecially if you want some kind of general implementation.

   Ian