Envelope of a signal
"Envelope" calculates the upper or lower envelope of a given
signal by interpolating between positive or negative peaks of the signal.
The upper envelope connects the relative maxima of the signal, whereas
the lower envelope connects the relative minima of the signal. All
values below (or above in the case of the lower envelope) the given threshold are not taken into account for the
calculation of the envelope function.
Parameters of "Envelope" are
- the type of envelope envtype which is either
- "Upper" (0) or
- "Lower" (1),
- the type of interpolation interp which is either
- "Linear" (0) or
- "Spline" (1) and
- the threshold t.
y = Envelope(x,envtype,interp,t);