Octave spectrum (ANSI S1.11-2004)

Function for estimating the octave spectrum of a given signal.

This function estimates and display the octave spectrum (optionally A-weighted) in dB scale of a given 1D signal.
It has been coded in compliance with ANSI S1.11-2004 and with full compatibility with Octave.

Inputs and outputs are reported below:
INPUTS
s = input signal
fs = sampling frequency
b = octave ratio reccomended 1 or 3
dbRef = standard reference for decibel scale calculation, default value: 1
weightFlag = A-weighting [0,1], default value: 1
plotFlag = generate octave diagram [0,1], default value: 1

OUTPUTS
S = octave spectrum (dB)
fm = midband frequency
overall_lev = overall level
overall_levA = weighted overall level
sfilt = third-octave filtered signals