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PARAMETER ESTIMATION FOR INTELLIGENT VOLUME CONTROLLER THROUGH NEURAL NETWORK CLASSIFIER
What is I.V.C?
I.V.C. is a device which used as volume controller. It is used to minimize the surroundings noise and boosting the desire voice signal to a optimal value. It is use in mobile phone, DVD player and CD player.
BLOCK DIAGRAM OF INTELLIGENT VOLUME  CONTROLLER FOR MOBILE PHONES
Speech Frames
COMMANDS USED IN MATLAB
LPC :
>> load 's2car1';
>> [s1,fs1,bits] = wavread('s2car1');
>> [a,g] = lpc(s1,10);
>> [a,g] = lpc(s1,10)
POWER SPECTRUM :>> tm=length(s1)/fs1;>> N=256;>> t=N/2;>> imagesc([0 tm],[0 fs1],abs(b(1:t,).^2),axis xy; >> title('Power spectrum of s2 car noise2 for N = 256');
>> xlabel('Time[s]');
>> ylabel('Frequency[Hz]');
>> colorbar;
MFCC – Filter Bank
Mel-scale
Human hearing is not equally sensitive to all frequency bands
Less sensitive at higher frequencies, roughly > 1000 Hz