vc2.m

这是一个用于语音信号处理的工具箱

% Script: vc2.m is an m-file to execute the voice conversion algorithm which
%         matches the speaking rate to the source speaker.
%
%         vc2.m is a call function evoked by vcapp.m on figure(vwin_f)
 
  %-----------------------------------------------------------------------
  % time-align speech2 to match to the pace of speech1 
  %-----------------------------------------------------------------------

  disp('Align the source parameter in time axis...')

  % construct the warping path
  x_ref=[];
  for k=1:length(vcidx11)
       x_ref=[x_ref vcidx11(k):1:vcidx12(k)];
  end

  [dum,tM2]=size(road);
  road1=road;
  
  del_idx=[];
  for k=2:tM2
      if road(2,k)-road(2,k-1)==0
           del_idx=[del_idx k];
      end
  end
  road1(:,del_idx)=[];

  y_ref=interp1(road1(2,:),road1(1,:),x_ref);
  y_ref=round(y_ref);
  road1=[x_ref; y_ref];

  % 1 calculate pitch period (pp1) for each frame for speech1
  [M1,dum]=size(cofa1);
  pp1=zeros(1,M1);
  for k=1:length(vcidx11)
      s_fram=vcidx11(k);
      e_fram=vcidx12(k);
      for kf=s_fram:e_fram
          spoint=(kf-1)*m_len+1;
          epoint=spoint+2*m_len+Order;
          pitchs=diff( gci1( gci1>spoint & gci1<epoint ) );
          if isempty(pitchs)
             pp1(kf)=pp1(kf-1);
          else
             pp1(kf)=mean(pitchs);
          end
      end 
  end

  % 2 calculate pitch period (pp2) for each frame for speech2
  [M2,dum]=size(cofa2);
  pp2=zeros(1,M2);
  for k=1:length(vcidx21)
      s_fram=vcidx21(k);
      e_fram=vcidx22(k);
      for kf=s_fram:e_fram
          spoint=(kf-1)*m_len+1;
          epoint=spoint+2*m_len+Order;
          pitchs=diff( gci2(gci2>spoint & gci2<epoint ) );
          if isempty(pitchs)
             pp2(kf)=pp2(kf-1);
          else
             pp2(kf)=mean(pitchs);
          end
      end 
  end
  clear pitchs;

  % 1.3 collect the pitch period data ****
  pp1_ref=pp1( x_ref );
  pp2_ref=pp2( y_ref );

  % 1.4 collect the ngm data ****
  tM2=length(x_ref);

  tmp=ngm1(x_ref, : );
  tmp1=tmp(1:4*tM2);
  ngm1_ref(1)=mean( tmp1(1:4) );
  for kf=2:tM2-1
      ngm1_ref(kf)=mean( tmp1( kf*4-4 : kf*4+1 ) );
  end
  ngm1_ref(tM2)=mean( tmp1(4*tM2-3:4*tM2) );

  tmp=ngm2(y_ref, : );
  tmp2=tmp(1:4*tM2);
  ngm2_ref(1)=mean( tmp2(1:4) );
  for kf=2:tM2-1
      ngm2_ref(kf)=mean( tmp2( kf*4-4 : kf*4+1 ) );
  end
  ngm2_ref(tM2)=mean( tmp2(4*tM2-3:4*tM2) );

  clear tmp tmp1 tmp2;

  % 1.5 collect the gpcf1 data ****
  gpcf1_ref=gpcf1( x_ref,: );
  gpcf2_ref=gpcf2( y_ref,: );

  % 1.6 collect the FF1 data ****
  if vt==2
     FF1_ref=FF1( x_ref, :);
     FF2_ref=FF2( y_ref, :);
  end

  %-----------------------------------------------------------------------%
  % Voice Conversion Algorithm                                            %
  %       method=1  bias model                                            %
  %       method=2  linear model                                          %
  %       method=3  just copy the value from target                       %
  %       method=4  do not modify the value of the source but time-align  %
  %-----------------------------------------------------------------------%

  % the following acoustic features (parameters) are created
  %    vctyp3  = voicetype classifications
  %    gci3    = gci index
  %    cofa3   = LP coeffiecints
  %    gm3     = voiced gain contour
  %    gpcf3   = glottal pulse shape
  %    nidx3   = stochastic codebook index
  %    ngm3    = whole gain index
  %    FF3     = formant frequency
  %    FB3     = formant bandwidth
  %--------------------------------------------------------

  %************ copy vctyp3, cofa3 and nidx3 **************
  vctyp3=vctyp1;
  cofa3=cofa1;
  nidx3=nidx1;

  %---------------------------------------------------------
  %************** convert gci1 to match gci2  **************

  % find the starting and ending GCI points for the source speech
  for k=1:length(vcidx11)
      spoint=(vcidx11(k)-1)*m_len-m_len/4;
      [dum,idx]=min( abs(gci1-spoint) );
      gci_s(k)=gci1(idx);      % starting GCI point
      epoint=(vcidx12(k)-1)*m_len+5*m_len/4;
      [dum,idx]=min( abs(gci1-epoint) );
      gci_e(k)=gci1(idx);      % ending GCI point
  end

  gci3=[];
  gci_method=get(v_pp_pit,'Value');

  if gci_method==1

     out=lrest(pp1_ref, pp2_ref, 0, SHOW);
     b=out(1);
     pp3_ref=pp1_ref+b;

     kk=0;
     for k=1:length(vcidx11)
         s_fram=vcidx11(k);
         e_fram=vcidx12(k);

         spoint=gci_s(k);

         for kf=s_fram:e_fram
             kk=kk+1;
             epoint=kf*m_len+2*Order+1;
             if kf==e_fram
                 epoint=gci_e(k);
             end
             p00=pp3_ref( kk );
             gci_insert=gci_dis(p00,0,spoint,epoint);
             gci3=[gci3 gci_insert];
             o_spoint=spoint;
             spoint=max(gci_insert);
             if isempty(spoint)
                spoint=o_spoint;
             end
         end
         clear s_fram e_fram
     end
     disp('The bias model is used to convert the pitch contour.');
     disp(b);
     disp('Normalized Standard Deviation=');
     disp(out(3)/mean(pp2_ref));

  elseif gci_method==2
     out=lrest(pp1_ref,pp2_ref,1,SHOW);
     a=out(2);
     b=out(1);
     pp3_ref=a*pp1_ref+b;

     kk=0;
     for k=1:length(vcidx21)
         s_fram=vcidx21(k);
         e_fram=vcidx22(k);
         spoint=gci_s(k);

         for kf=s_fram:e_fram
             kk=kk+1;
             epoint=kf*m_len+2*Order+1;
             if ( kf==e_fram )
                epoint=gci_e(k);
             end
             p00=pp3_ref(kk);
             gci_insert=gci_dis(p00,0,spoint,epoint);
             gci3=[gci3 gci_insert];
             o_spoint=spoint;
             spoint=max(gci_insert);
             if isempty(spoint)
                spoint=o_spoint;
             end
         end
     end

     disp('The linear model is used to convert the pitch contour.');
     disp([a b]);
     disp('Normalized Standard Deviation=');
     disp(out(3)/mean(pp2_ref));

  elseif gci_method==3
     pp3_ref=pp2_ref;

     kk=0;
     for k=1:length(vcidx11)
         s_fram=vcidx11(k);
         e_fram=vcidx12(k);
         spoint=gci_s(k);

         for kf=s_fram:e_fram
             kk=kk+1;
             epoint=kf*m_len+2*Order;
             if kf==e_fram
                epoint=gci_e(k);
             end
             p00=pp3_ref( kk );
             gci_insert=gci_dis(p00,0,spoint,epoint);
             gci3=[gci3 gci_insert];
             o_spoint=spoint;
             spoint=max(gci_insert);
             if isempty(spoint)
                spoint=o_spoint;
             end
         end 
     end

  elseif gci_method==4

     gci3=gci1;
     pp3_ref=pp1_ref;

  end

  if SHOW==1
     figure(dtwdisplay_f);
     plot(x_ref,pp1_ref,'y',x_ref,pp3_ref,'r',x_ref,pp2_ref,'g');
     title('pitch conversion (source: yellow ; converted: red ; target:green)');
     pause(1);
  end 
  clear gci_insert p00 pp1 pp2 pp1_ref pp2_ref pp3_ref tmp;

  %---------------------------------------------------
  %************ convert ngm1 to match ngm2  **********

  ngm3=ngm1;
  ngm_method=get(v_pp_gai,'Value');

  if ngm_method==1
     out=lrest(ngm1_ref, ngm2_ref, 0, SHOW)
     b=out(1);
     ngm3_ref=abs(ngm1_ref+b);

     x_ref=road1(1,:);
     tM2=length(x_ref);
     tmp_gm=zeros(tM2,4);

     % ---interpolate ngm3---
     s_fram=1;
     for k=1:length(vcidx11);
          e_fram=s_fram+vcidx12(k)-vcidx11(k);

          % smoothing the starting frame
          kf=s_fram;
             ngm3_ref(kf)=0.13*ngm3_ref(kf+1);
             gm_x=[1 m_len/2 m_len+m_len];
             gm_y=[0 ngm3_ref(kf) ngm3_ref(kf+1)];
             gm_z=m_len/4*[0 1 2 3]+m_len/8;
             tmp=interp1(gm_x,gm_y,gm_z,'spline');
             tmp_gm(kf,1:4)=tmp(:)';

          for kf=s_fram+1:e_fram-1
              gm_x=[-1*m_len/2 m_len/2 m_len+m_len];
              gm_y=[ngm3_ref(kf-1) ngm3_ref(kf) ngm3_ref(kf+1)];
              gm_z=m_len/4*[0 1 2 3]+m_len/8;
              tmp=interp1(gm_x,gm_y,gm_z);
              tmp_gm(kf,1:4)=tmp(:)';
          end

          % smoothing the ending frame
          kf=e_fram;
             ngm3_ref(kf)=0.13*ngm3_ref(kf-1);
             gm_x=[-1*m_len/2 m_len/2 m_len];
             gm_y=[ngm3_ref(kf-1) ngm3_ref(kf) 0];
             gm_z=m_len/4*[0 1 2 3]+m_len/8;