Code covered by the BSD License  

Highlights from
LPC Error

image thumbnail

LPC Error

by

 

30 Jan 2014 (Updated )

Shows the (flat spectrum) nature of the LPC error signal for a typical speech frame (voiced speech)

Callbacks_lpc_error_GUI25(f,C,start_path)
function Callbacks_lpc_error_GUI25(f,C,start_path)
%SENSE COMPUTER AND SET FILE DELIMITER
switch(computer)				
    case 'MACI64',		char= '/';
    case 'GLNX86',  char='/';
    case 'PCWIN',	char= '\';
    case 'PCWIN64', char='\';
    case 'GLNXA64', char='/';
end
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
x=C{1,1};
y=C{1,2};
a=C{1,3};
b=C{1,4};
u=C{1,5};
v=C{1,6};
m=C{1,7};
n=C{1,8};
lengthbutton=C{1,9};
widthbutton=C{1,10};
enterType=C{1,11};
enterString=C{1,12};
enterLabel=C{1,13};
noPanels=C{1,14};
noGraphicPanels=C{1,15};
noButtons=C{1,16};
labelDist=C{1,17};%distance that the label is below the button
noTitles=C{1,18};
buttonTextSize=C{1,19};
labelTextSize=C{1,20};
textboxFont=C{1,21};
textboxString=C{1,22};
textboxWeight=C{1,23};
textboxAngle=C{1,24};
labelHeight=C{1,25};
fileName=C{1,26};
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%PANELS
for j=0:noPanels-1
uipanel('Parent',f,...
'Units','Normalized',...
'Position',[x(1+4*j) y(1+4*j) x(2+4*j)-x(1+4*j) y(3+4*j)-y(2+4*j)]);
end
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%GRAPHIC PANELS
for i=0:noGraphicPanels-1
switch (i+1)
case 1
graphicPanel1 = axes('parent',f,...
'Units','Normalized',...
'Position',[a(1+4*i) b(1+4*i) a(2+4*i)-a(1+4*i) b(3+4*i)-b(2+4*i)],...
'GridLineStyle','--');
case 2
graphicPanel2 = axes('parent',f,...
'Units','Normalized',...
'Position',[a(1+4*i) b(1+4*i) a(2+4*i)-a(1+4*i) b(3+4*i)-b(2+4*i)],...
'GridLineStyle','--');
case 3
graphicPanel3 = axes('parent',f,...
'Units','Normalized',...
'Position',[a(1+4*i) b(1+4*i) a(2+4*i)-a(1+4*i) b(3+4*i)-b(2+4*i)],...
'GridLineStyle','--');
case 4
graphicPanel4 = axes('parent',f,...
'Units','Normalized',...
'Position',[a(1+4*i) b(1+4*i) a(2+4*i)-a(1+4*i) b(3+4*i)-b(2+4*i)],...
'GridLineStyle','--');
end
end
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%TITLE BOXES
for k=0:noTitles-1
switch (k+1)
case 1
titleBox1 = uicontrol('parent',f,...
'Units','Normalized',...
'Position',[u(1+4*k) v(1+4*k) u(2+4*k)-u(1+4*k) v(3+4*k)-v(2+4*k)],...
'Style','text',...
'FontSize',textboxFont{k+1},...
'String',textboxString(k+1),...
'FontWeight',textboxWeight{k+1},...
'FontAngle',textboxAngle{k+1});
end
end
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%BUTTONS
for i=0:(noButtons-1)
enterColor='w';
if strcmp(enterType{i+1},'pushbutton')==1 ||strcmp(enterType{i+1},'text')==1
enterColor='default';
end
if (strcmp(enterLabel{1,(i+1)},'')==0 &&...
        strcmp(enterLabel{1,(i+1)},'...')==0) %i.e. there is a label
%creating a label for some buttons
uicontrol('Parent',f,...
'Units','Normalized',...
'Position',[m(1+2*i) n(1+2*i)-labelDist-labelHeight(i+1) ...
(m(2+2*i)-m(1+2*i)) labelHeight(i+1)],...
'Style','text',...
'String',enterLabel{i+1},...
'FontSize', labelTextSize(i+1),...
'HorizontalAlignment','center');
end
switch (i+1)
case 1
button1=uicontrol('Parent',f,...
'Units','Normalized',...
'Position',[m(1+2*i) n(1+2*i) (m(2+2*i)-m(1+2*i)) (n(2+2*i)-n(1+2*i))],...
'Style',enterType{i+1},...
'String',enterString{i+1},...
'FontSize', buttonTextSize(1+i),...
'BackgroundColor',enterColor,...
'HorizontalAlignment','center',...
'Callback',@button1Callback);
case 2
button2=uicontrol('Parent',f,...
'Units','Normalized',...
'Position',[m(1+2*i) n(1+2*i) (m(2+2*i)-m(1+2*i)) (n(2+2*i)-n(1+2*i))],...
'Style',enterType{i+1},...
'String',enterString{i+1},...
'FontSize', buttonTextSize(1+i),...
'BackgroundColor',enterColor,...
'HorizontalAlignment','center',...
'Callback',@button2Callback);
case 3
button3=uicontrol('Parent',f,...
'Units','Normalized',...
'Position',[m(1+2*i) n(1+2*i) (m(2+2*i)-m(1+2*i)) (n(2+2*i)-n(1+2*i))],...
'Style',enterType{i+1},...
'String',enterString{i+1},...
'FontSize', buttonTextSize(1+i),...
'BackgroundColor',enterColor,...
'HorizontalAlignment','center',...
'Callback',@button3Callback);
case 4
button4=uicontrol('Parent',f,...
'Units','Normalized',...
'Position',[m(1+2*i) n(1+2*i) (m(2+2*i)-m(1+2*i)) (n(2+2*i)-n(1+2*i))],...
'Style',enterType{i+1},...
'String',enterString{i+1},...
'FontSize', buttonTextSize(1+i),...
'BackgroundColor',enterColor,...
'HorizontalAlignment','center',...
'Callback',@button4Callback);
case 5
button5=uicontrol('Parent',f,...
'Units','Normalized',...
'Position',[m(1+2*i) n(1+2*i) (m(2+2*i)-m(1+2*i)) (n(2+2*i)-n(1+2*i))],...
'Style',enterType{i+1},...
'String',enterString{i+1},...
'FontSize', buttonTextSize(1+i),...
'BackgroundColor',enterColor,...
'HorizontalAlignment','center',...
'Callback',@button5Callback);
case 6
button6=uicontrol('Parent',f,...
'Units','Normalized',...
'Position',[m(1+2*i) n(1+2*i) (m(2+2*i)-m(1+2*i)) (n(2+2*i)-n(1+2*i))],...
'Style',enterType{i+1},...
'String',enterString{i+1},...
'FontSize', buttonTextSize(1+i),...
'BackgroundColor',enterColor,...
'HorizontalAlignment','center',...
'Callback',@button6Callback);
case 7
button7=uicontrol('Parent',f,...
'Units','Normalized',...
'Position',[m(1+2*i) n(1+2*i) (m(2+2*i)-m(1+2*i)) (n(2+2*i)-n(1+2*i))],...
'Style',enterType{i+1},...
'String',enterString{i+1},...
'FontSize', buttonTextSize(1+i),...
'BackgroundColor',enterColor,...
'HorizontalAlignment','center',...
'Callback',@button7Callback);
case 8
button8=uicontrol('Parent',f,...
'Units','Normalized',...
'Position',[m(1+2*i) n(1+2*i) (m(2+2*i)-m(1+2*i)) (n(2+2*i)-n(1+2*i))],...
'Style',enterType{i+1},...
'String',enterString{i+1},...
'FontSize', buttonTextSize(1+i),...
'BackgroundColor',enterColor,...
'HorizontalAlignment','center',...
'Callback',@button8Callback);
case 9
button9=uicontrol('Parent',f,...
'Units','Normalized',...
'Position',[m(1+2*i) n(1+2*i) (m(2+2*i)-m(1+2*i)) (n(2+2*i)-n(1+2*i))],...
'Style',enterType{i+1},...
'String',enterString{i+1},...
'FontSize', buttonTextSize(1+i),...
'BackgroundColor',enterColor,...
'HorizontalAlignment','center',...
'Callback',@button9Callback);
case 10
button10=uicontrol('Parent',f,...
'Units','Normalized',...
'Position',[m(1+2*i) n(1+2*i) (m(2+2*i)-m(1+2*i)) (n(2+2*i)-n(1+2*i))],...
'Style',enterType{i+1},...
'String',enterString{i+1},...
'FontSize', buttonTextSize(1+i),...
'BackgroundColor',enterColor,...
'HorizontalAlignment','center',...
'Callback',@button10Callback);
case 11
button11=uicontrol('Parent',f,...
'Units','Normalized',...
'Position',[m(1+2*i) n(1+2*i) (m(2+2*i)-m(1+2*i)) (n(2+2*i)-n(1+2*i))],...
'Style',enterType{i+1},...
'String',enterString{i+1},...
'FontSize', buttonTextSize(1+i),...
'BackgroundColor',enterColor,...
'HorizontalAlignment','center',...
'Callback',@button11Callback);
case 12
button12=uicontrol('Parent',f,...
'Units','Normalized',...
'Position',[m(1+2*i) n(1+2*i) (m(2+2*i)-m(1+2*i)) (n(2+2*i)-n(1+2*i))],...
'Style',enterType{i+1},...
'String',enterString{i+1},...
'FontSize', buttonTextSize(1+i),...
'BackgroundColor',enterColor,...
'HorizontalAlignment','center',...
'Callback',@button12Callback);
case 13
button13=uicontrol('Parent',f,...
'Units','Normalized',...
'Position',[m(1+2*i) n(1+2*i) (m(2+2*i)-m(1+2*i)) (n(2+2*i)-n(1+2*i))],...
'Style',enterType{i+1},...
'String',enterString{i+1},...
'FontSize', buttonTextSize(1+i),...
'BackgroundColor',enterColor,...
'HorizontalAlignment','center',...
'Callback',@button13Callback);
end
end

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%USER CODE FOR THE VARIABLES AND CALLBACKS
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% Initialize Variables
    curr_file=1;
    fs=8000;
    directory_name='abcd';
    wav_file_names='abce';
    fin_path='filename';
    fname='output';
    nsamp=1;
    ss=1;
    istart=1;
    Lm=40;
    L=640;
    Rm=10;
    R=160;
    iwin_LPC=1;
    nfft=2048;
    win=hamming(640);
    p=12;
    ilpc=2;
    iwin_STFT=1;
    x=[];
    error=[];
    e=[];

% Name the GUI
    set(f,'Name','lpc_error_spectra');

% CALLBACKS
% Callback for button1 -- Get Speech Files Directory
 function button1Callback(h,eventdata)
     directory_name=uigetdir(start_path,'dialog_title');
     A=strvcat(strcat((directory_name),[char,'*.wav']));
     struct_filenames=dir(A);
     wav_file_names={struct_filenames.name};
     set(button2,'String',wav_file_names);
     
% once the popupmenu/drop down menu is created, by default, the first
% selection from the popupmenu/drop down menu id not called
    indexOfDrpDwnMenu=1;
    
% by default first option from the popupmenu/dropdown menu will be loaded
    [curr_file,fs]=loadSelection(directory_name,wav_file_names,indexOfDrpDwnMenu);
 end

% Callback for button2 -- Choose speech file for play and plot
 function button2Callback(h,eventdata)
     indexOfDrpDwnMenu=get(button2,'val');
     [curr_file,fs]=loadSelection(directory_name,wav_file_names,indexOfDrpDwnMenu);
 end

%*************************************************************************
% function -- load selection from designated directory and file
%
function [curr_file,fs]=loadSelection(directory_name,wav_file_names,...
    indexOfDrpDwnMenu);
%
% read in speech/audio file
% fin_path is the complete path of the .wav file that is selected
    fin_path=strcat(directory_name,char,strvcat(wav_file_names(indexOfDrpDwnMenu)));
    
% clear speech/audio file
    clear curr_file;
    
% read in speech/audio signal into curr_file; sampling rate is fs 
    [curr_file,fs]=wavread(fin_path);
    
% create title information with file, sampling rate, number of samples
    fname=wav_file_names(indexOfDrpDwnMenu);
    FS=num2str(fs);
    nsamp=num2str(length(curr_file));
    file_info_string=strcat('  file: ',fname,', fs: ',FS,' Hz, nsamp:',nsamp);
    
% read in filename (fname) from cell array
    fname=wav_file_names{indexOfDrpDwnMenu};
end

% Callback for button9 -- Play Speech File
    function button9Callback(h,eventdata)
        soundsc(curr_file,fs);
    end

% Callback for button3 -- ilpc: lpc analysis type, 1:autocorrelation
% method, 2:covariance method
 function button3Callback(h,eventdata)
     ilpc=get(button3,'val');
 end

% Callback for button4 -- iwin_LPC: LPC analysis window type; 1:Hamming,
% 2:Rectangular
 function button4Callback(h,eventdata)
     iwin_LPC=get(button4,'val');
 end

% Callback for button11 -- iwin_STFT: STFT analysis window type; 1:Hamming,
% 2:Rectangular
 function button11Callback(h,eventdata)
     iwin_STFT=get(button11,'val');
 end

% Callback for button5 -- Lm: frame length in msec; must be converted to
% samples at processing rate
 function button5Callback(h,eventdata)
     Lm=str2num(get(button5,'string'));
     if (Lm < 1 || Lm > 100)
        waitfor(errordlg('The value of frame duration must be between 1 and 100'));
        return;
    end
     L=round(Lm*fs/1000);
 end

% Callback for button10 -- Rm: frame shift in msec; must be converted to
% samples at processing rate
 function button10Callback(h,eventdata)
     Rm=str2num(get(button10,'string'));
     if (Rm < 1 || Rm > 100)
        waitfor(errordlg('The value of frame shift must be between 1 and 100'));
        return;
    end
     R=round(Lm*fs/1000);
 end

% Callback for button6 -- p: lpc analysis order
 function button6Callback(h,eventdata)
     p=str2num(get(button6,'string'));
     if (p < 4 || p > 32)
          waitfor(errordlg('The value of lpc analysis order must be positive integer between 4 and 32'));
          return;
    end
 end

% Callback for button7 -- set up lpc error spectra
 function button7Callback(h,eventdata)
     
% check editable buttons for changes
    button3Callback(h,eventdata);  % ilpc: lpc analysis type
    button11Callback(h,eventdata);  % iwin_STFT: STFT window type
    button4Callback(h,eventdata);  % iwin_LPC: LPC Autocorrelation window type
    button5Callback(h,eventdata);  % Lm: frame length in msec
    button10Callback(h,eventdata);  % Rm: frame length in msec
    button6Callback(h,eventdata);  %  p: LPC system order
    
% initialize signal processing parameters
    ss=1;
    istart=1;
    
% save speech file in x
    x=curr_file;
    
% plot entire speech file in graphics Panel 4,  and use graphics 
% cursor to find region of interest
    ss=plot_speech_cursor(x,ss,istart,fs,L,graphicPanel4);
    
% plot out expanded speech frame in graphics Panel 4 and use 
% graphics cursor to home in on region of interest and choose 
% analysis frame starting sample
    plot_frame(x,ss,L,p,fs,ilpc,iwin_LPC,graphicPanel4);
 end

% Callback for button12 -- Use Current Frame
    function button12Callback(h,eventdata)
    
% compute lpc and error analysis on frame of speech
    if (ilpc == 1)
        [x,xs1,xs2,e,es]=lpc_error_spectrum(curr_file,fs,ss,iwin_LPC,iwin_STFT,L,nfft,p);
        n1=0:L-1;
    else
        [x,xs1,error,es,xs2]=lpc_analysis_covariance(curr_file,ss,L,p,nfft,iwin_STFT);
        n1=-p:L-1;
    end
    
% plot the following signals and spectra
%   graphics Panel 4 -- weighted speech frame
%   graphics Panel 3 -- LPC error signal
%   graphics Panel 2 -- STFT of speech frame, overlapped with lpc spectrum
%   graphics Panel 1 -- lpc error spectrum (log magnitude response)
    n2=L:L-1+p;
    freq=0:fs/nfft:fs/2;
    stitle=sprintf('filename: %s, ss: %d, lpc parameters, L: %d, p:%d',...
        fname,ss,L,p);
    
% set up titleBox1 with filename and lpc analysis parameters
    stitle1=strcat('LPC Error Spectra -- ',stitle);
	set(titleBox1,'String',stitle1);
    set(titleBox1,'FontSize',20);
    
% replot original speech frame
    x=curr_file;
    plot_frame(x,ss,L,p,fs,ilpc,iwin_LPC,graphicPanel4);
    
% plot lpc error signal in graphics Panel3
    plot_error(e,error,ss,L,p,fs,ilpc,iwin_LPC,graphicPanel3);
        
% clear graphics Panel 2
    reset(graphicPanel2);
    axes(graphicPanel2);
    cla;
    
% plot STFT log magnitude of speech analysis frame, along with lpc
% log magnitude in graphics Panel 2
    plot(freq,xs1(1:nfft/2+1),'g','LineWidth',2),...
        grid on,xlabel('Frequency in Hz'),ylabel('Log Magnitude (dB)');
    hold on, plot(freq,xs2(1:nfft/2+1),'b','LineWidth',2),axis tight;
    legend('signal spectrum','LPC spectrum');
    
% clear graphics Panel 1
    reset(graphicPanel1);
    axes(graphicPanel1);
    cla;
    
% plot lpc error log magnitude spectrum in graphics Panel 1
    plot(freq,es(1:nfft/2+1),'r','LineWidth',2),...
        xlabel('Frequency in Hz'),ylabel('Log Magnitude (dB)'),...
        axis tight, grid on, legend('error spectrum','location','SouthEast');
    end

% Callback for button13 -- Use Next Frame
    function button13Callback(h,eventdata)
% check editable buttons for changes
    button3Callback(h,eventdata);  % ilpc: lpc analysis type
    button11Callback(h,eventdata);  % iwin_STFT: STFT window type
    button4Callback(h,eventdata);  % iwin_LPC: LPC Autocorrelation window type
    button5Callback(h,eventdata);  % Lm: frame length in msec
    L=round(Lm*fs/1000);
    button10Callback(h,eventdata);  % Rm: frame length in msec
    R=round(Rm*fs/1000);
    button6Callback(h,eventdata);  %  p: LPC system order
    
    ss=ss+R;
% plot out expanded speech frame in graphics Panel 4 and use 
% graphics cursor to home in on region of interest and choose 
% analysis frame starting sample
    x=curr_file;
    plot_frame(x,ss,L,p,fs,ilpc,iwin_LPC,graphicPanel4);
    button12Callback(h,eventdata)
    end

% Callback for button8 -- close GUI
 function button8Callback(h,eventdata)
     close(gcf);
 end
end

Contact us