lp_go.m

这是一个用于语音信号处理的工具箱

%
% Callback function for popup menu in the Frequency Analysis window
% Author : Minkyu Lee
% Date : 27-Feb-1995
% Modified by Karthik May 27 1997
% Modified by D. G. Childers

% Set position and size of analysis window
PV=[270 100 519 240];
s2 = 'Frequency Domain Analysis - Output';

% Open analysis window	
% Open analysis window
while exist('freq_out_win_h')==1
   try1 = 'get(freq_out_win_h,''position'');';
   eval(try1,catch2);
   if check ==0
      clear freq_out_win_h;
      check = 1;
      break;
   end
   s1 = get(freq_out_win_h,'Name');
   if ~strcmp(s1,s2)
      clear freq_out_win_h;
      break;
   end
   figure(freq_out_win_h);
   break;
end;

if exist('freq_out_win_h')~=1;
	freq_out_win_h=figure('Position',PV,...
      'Resize','on',...
      'Name',s2,...
		'Numbertitle','off');
end

% set parameters

if lp_window == 1
	window = hamming(lp_frame_len);	% Window type
elseif lp_window == 2
	window = hanning(lp_frame_len);	% Window type
elseif lp_window == 3
	beta=0.5;
	window = kaiser(lp_frame_len,beta);	% Window type
elseif lp_window == 4
	window = triang(lp_frame_len);	% Window type
elseif lp_window == 5
	window = bartlett(lp_frame_len);	% Window type
elseif lp_window == 6
	window = blackman(lp_frame_len);	% Window type
elseif lp_window == 7
	window = boxcar(lp_frame_len);	% Window type
elseif lp_window == 8
	rdb=3;
	window = chebwin(lp_frame_len,rdb);	% Window type
end

epsilon=1e-15;	
val=get(lp_po_method_h,'Value');
button=1;
while button == 1
	if freq_lp_mark_flag == 0
		if lp_frame_len > length(SPEECH)			S=sprintf('Analysis window length is longer that input data. %d of zeros are padded',lp_frame_len-LEN);
			disp(S);
			temp=zeros(lp_frame_len-LEN,1);
			speech1=[SPEECH;temp];
		else
			S=sprintf('The analysis frame is the first %d points of current data window',lp_frame_len);
			disp(S);
			speech1=SPEECH_OLD(LEFT:LEFT+lp_frame_len-1);
		end
		button=0;
	else
		figure(ana_wav_win_h);
      [x,y,button]=ginput(1);
      x=round(x);
   		if button ~= 1
            return;
         end
         
         speech1=SPEECH_OLD(x(1):x(1)+lp_frame_len-1);
         figure(freq_out_win_h);
      end
      FFT = fft(window.*speech1,lp_frame_len);
      
   wait_window = figure('Numbertitle','off',...
   'Color',BACK_COLOR,...
   'Name','Please be patient...',...
   'Position',[117 248 560 150]);

   wait_window_display = uicontrol('Style','Text',...
   'Position',[50 50 410 30],...
   'Backgroundcolor','white',...
   'Foregroundcolor','blue',...
   'String','These methods may take a while...please wait');

   pause(0.01);
      
      if val == 1
         fn = 'Frequency analysis (autocorrelation method)';
         [A sig2]=autocorr(window.*speech1,lp_frame_len,lp_num_poles);
      elseif val == 2
         fn = 'Frequency analysis (covariance method)';
         mode=0;		% for covariance method
         [iflag A sig2]=covmcov(speech1,lp_frame_len,lp_num_poles,mode,epsilon);
      elseif val == 3
         fn = 'Frequency analysis (modified cov. method)';
         mode=1;		% for modified covariance method
         [iflag A sig2]=covmcov(speech1,lp_frame_len,lp_num_poles,mode,epsilon);
      elseif val == 4
         fn='Frequency analysis (Burg algorithm)';
         [A sig2]=burg(window.*speech1,lp_frame_len,lp_num_poles);
      elseif val == 5
         fn = 'Frequency analysis (Recursive MLE algorithm)';
         [A sig2]=rmle(window.*speech1,lp_frame_len,lp_num_poles);
      elseif val == 6
         fn = 'Perceptual linear prediction analysis';
         [A rc sig2 spectra audspe nfilt ] = plp( speech1,length(speech1),lp_num_poles,1/Ts);
      end
      
   set(wait_window_display,'String','Thanks for being patient.  Now plotting');
   pause(0.01);
   close(wait_window);
   clear wait_window;

      
      error=filter([1 A],1,speech1);
      eng=sqrt(error'*error);
      [H W]=freqz(eng,[1 A],lp_frame_len/2);
      
      % plot the spectrum and pole_zero plot
      if val == 6
         zi=roots([1 A]);
         mm=1;
         for kk=1:length(zi)
            if angle(zi(kk)) >= 0
               zzi(mm)=zi(kk);
               mm=mm+1;
            end
         end
         fi=17*angle(zzi)/pi;
         bi=-34*log(abs(zzi))/pi;
         ff=600*sinh(fi/6);
         fb=600*sinh(bi/6);
         
         vh=1:length(spectra)/2;
         vh=vh/length(spectra)*1/(Ts);
         subplot(121), plot(vh,10*log10(spectra(1:length(spectra)/2)));
         xlabel('Frequency in (Hz)');
         title(fn);
         vb=1:length(H);
         vb=vb/length(H)*nfilt;
         subplot(122), plot(vb,20*log10(sig2*abs(H)));
         xlabel('Frequency in (Bark)');
         title(fn);
         fsave=20*log10(sig2*abs(H));
      else
         vh=1:lp_frame_len/2;
         vh=vh/(lp_frame_len/2)*1/(2*Ts);
         subplot(121),plot(vh,20*log10(abs(FFT(1:lp_frame_len/2))));
         title(fn);
         hold on;
         plot(vh,20*log10(abs(H)), ':r');
         xlabel('Frequency in (Hz)');
         fsave=20*log10(abs(H));
         hold off;
         subplot(122), zplane([], [1 A]);
         title('pole-zero plot');
         xlabel('Real');
         ylabel('Imag');
      end
   end