allow to use input envelope in noise sound

scripts/noisesound.m

@@ -1,12 +1,12 @@
-function noisesound( sInput, sOutput, dur )
+function noisesound( sInput, sOutput, dur, tauenv )
 % NOISESOUND - create a random-phase noise signal with input spectrum
 %
 % Usage:
 % noisesound( sInput, sOutput, dur )
 %
 % sInput : name of input sound file
 % sOutput: name of output sound file
-% dur    : duration (and fft length) of the output sound file
+% dur    : duration (and fft length) of the output sound file. If dur==0 then the original duration is used.
 %
 % Only the first channel of the input signal is used. The absolute
 % level of the output signal is not matched with the input
@@ -16,16 +16,31 @@ function noisesound( sInput, sOutput, dur )
 % of non-overlapping fragments of length duration is used.
 %
 % Author: Giso Grimm
-% Date: 1/2014
+% Date: 1/2014, 2024
   ;
   [x,fs] = audioread(sInput);
-  dur = round(dur*fs);
+  if dur > 0
+    dur = round(dur*fs);
+  else
+    dur = size(x,1);
+  end
+  if nargin < 4
+    tauenv = 0;
+  end
   x(:,2:end) = [];
+  rms_in = sqrt(mean(x.^2));
   x = buffer(x,dur);
+  env = mean(abs(hilbert(x)),2);
   X = sqrt(mean(abs(realfft(x)).^2,2));
   X = X .* exp(2*pi*i*rand(size(X)));
   x = realifft(X);
-  x = 0.9*x / max(abs(x(:)));
+  if tauenv > 0
+    rms_out = sqrt(mean(x.^2));
+    x = x .* (rms_in./rms_out);
+    x = x .* env;
+  else
+    x = 0.9*x / max(abs(x(:)));
+  end
   audiowrite(sOutput,x,fs);
 
 function y = realfft( x )