cbf.m

DSK6713 Speech.rar語音訊號處理應用範例程序

% ================================================================
% CBF : Frequency Response of Critical Band Filter Bank
% ----------------------------------------------------------------
% [ total channel number = 20 ]
% ================================================================
function CBF=cbf(sampling_rate);
global fft_point
f=sampling_rate*(1:fft_point/2-1)/fft_point;
fl(1)=0;
for ch=1:21
   if ch<=10
      fc(ch)=ch*(1000/10);
   else
      fc(ch)=10^(3+(log10(4000)-3)*(ch-10)/10);
   end
end
for ch=1:20
   fl(ch+1)=fc(ch);
   fh(ch)=fc(ch+1);
   hbwl(ch)=fc(ch)-fl(ch);
   hbwh(ch)=fh(ch)-fc(ch);
   point_index=length(f);
   for i=1:point_index
      if (f(i)<=fl(ch)) | (f(i)>=fh(ch))
         CBF(ch,i)=0;
      elseif f(i)<=fc(ch)
         CBF(ch,i)=2*(f(i)-fl(ch))/hbwl(ch);
      else 
         CBF(ch,i)=2*(fh(ch)-f(i))/hbwh(ch);
      end
   end
end
% ================================================================