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 Hi Experts.

 I wanna normalize my sound stream by loudness (energy / pressure /

 intensity) , not by peaks.

 How i do it ?

 Is available Jack plugin for so what ?

 What is (we hear as) "loudness" ?

 RMS or +(average) or something else ?

 Is somewhere available examples how to calculate RMS ?

 Is it done simlpe by :

  int i, n;  double sums, rms;

  sums=3D0.0;  n=3D10;  rms=3D0;

  for(i=3D0; i 10 kHz ?

 How to calculate RMS with hi-precision for frequencies > 10 kHz ?

 With inerpolation or so ?

 What is reference ( 0dB ) RMS for example for 16bit PCM signal 1024

 samples ?

   sqrt( 1024*(0x7FFF ^ 2) / 1024 )  =3D=3D  sqrt( (0x7FFF

 ^ 2)  ) =3D=3D 0x7FFF 

 Is it simple  0x7FFF (32000 dec) ?

 How to calc RMS for stereo signal ?

 So , or somehow else ?

 for(i=3D0; iHi Experts.I wanna normalize my sound str=

eam by loudness (energy / pressure / intensity) , not by peaks.How i =

do it ?Is available Jack plugin for so what ?What is (we =

hear as) "loudness" ?RMS or +(average) or something else ?Is somewhere available examples how to calculate RMS ?Is it done sim=

lpe by : int i, n;  double sums, rms; sums=

=3D0.0;  n=3D10;  rms=3D0; for(i=3D0; i<n;i++) {   sums =3D sums + ( (double)i * (double)i );  } rms =3D sqrt(sums / n); printf("    =

      rms =3D %12.12f\n\n", rms );Is s=

o sipmple algo good enough for frequencies > 10 kHz ?How to calcul=

ate RMS with hi-precision for frequencies > 10 kHz ?With inerpolat=

ion or so ?What is reference ( 0dB ) RMS for example for 16bit =

PCM signal 1024 samples ?  sqrt( 1024*(0x7FFF ^ 2) / 1024 )&#160=

; =3D=3D  sqrt( (0x7FFF ^ 2)  ) =3D=3D 0x7FFF  Is it s=

imple  0x7FFF (32000 dec) ?How to calc RMS for stereo sign=

al ?So , or somehow else ?for(i=3D0; i<n;i++) {&#=

160; ....   sums =3D sampleL/2 + sampleR/2;  }In case operating with float point, what should be a bit faster,  =

/ 2  or * 0.5 ?How to gotta RMS value in dB ? &=

#160; 20 x log10(Measured/Reference0_dB)  or 10 x log10(Measured=

/Reference0_dB)  ??Im just physics student and im new in D=

SP,so pleaz no angree about simple or stuppid questions.A=

ny examples and hints welcomed.Many Tnx in advance.Alf     ----

=0A

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