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<DIV><FONT face="Comic Sans MS" size=2>Hi,</FONT></DIV>
<DIV><FONT face="Comic Sans MS" size=2>Thanks for mail.</FONT><BR>>Your
terminology is not very clear. What exactly do you mean by<BR>>'average' RMS
and 'max' RMS ? The 'M' in RMS stands for 'mean',<BR>>so it is already an
average over all samples considered, and</DIV>
<DIV><BR><FONT face="Comic Sans MS" size=2>I'm using 25ms of window for
calculating Max RMS,meaning is in</FONT></DIV>
<DIV><FONT face="Comic Sans MS" size=2>every 25 ms I calculate RMS and
compare it with previous value </FONT></DIV>
<DIV><FONT face="Comic Sans MS" size=2>if current 25 ms RMS value is bigger than
previous value I retain</FONT></DIV>
<DIV><FONT face="Comic Sans MS" size=2>this value, using this I find MAX RMS
value for 25ms in file and call</FONT></DIV>
<DIV><FONT face="Comic Sans MS" size=2>it MAX RMS value as it is in adobe
audition.</FONT></DIV>
<DIV> </DIV>
<DIV>>That is, by definition of RMS = square Root of the Mean of the
<BR>>Squares, the RMS value of the N samples, expressed in the
same<BR>>unit as the samples themselves. <BR><BR>> >AvgRMS = 20.0 *
log10 ( rms /2^N-1)</DIV>
<DIV><BR>>You may be confusing two values of N here, the first being
the<BR>>number of samples, as in equation (1), and the second
being<BR>>the number of bits.<BR></DIV>
<DIV><FONT face="Comic Sans MS" size=2>Sorry for confusion in dB conversion
algorithm, it is surely</FONT></DIV>
<DIV><FONT face="Comic Sans MS" size=2>depth of sample in number of
bits.</FONT></DIV><FONT face="Comic Sans MS" size=2></FONT>
<DIV><BR>> normalised_rms = rms / (2^(B-1))<BR>>and then convert to
dB:<BR>> normalised_rms_in_dB = 20 * log10 (normalised_rms).</DIV>
<DIV><BR><FONT face="Comic Sans MS" size=2>your are right here as i'm also doing
the same. My requirement is</FONT></DIV>
<DIV><FONT face="Comic Sans MS" size=2>like Adobe audition my application
has to calculate the </FONT><FONT face="Comic Sans MS" size=2>Average RMS
power</FONT></DIV>
<DIV><FONT face="Comic Sans MS" size=2>for a wave audio file using </FONT><FONT
face="Comic Sans MS" size=2>time window system.</FONT></DIV>
<DIV><FONT face="Comic Sans MS" size=2> I'm </FONT><FONT
face="Comic Sans MS" size=2>trying to do the same to calculate the Average RMS
</FONT><FONT face="Comic Sans MS" size=2>but confusion is my
<BR>calculated Avrg RMS value matches with Total RMS value of
the adobe edition.</FONT></DIV>
<DIV><FONT face="Comic Sans MS" size=2>How to calculate the Average RMS ,
if above algorithm </FONT><FONT face="Comic Sans MS" size=2>calculates Total
RMS.</FONT></DIV>
<DIV><FONT face="Comic Sans MS" size=2></FONT> </DIV>
<DIV><FONT face="Comic Sans MS" size=2></FONT> </DIV>
<DIV><FONT face="Comic Sans MS" size=2>BR</FONT></DIV>
<DIV><FONT face="Comic Sans MS" size=2>chandrashekhar </FONT></DIV>
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