function qrsFes=FecgQRSfDet(X,fs,cName,qrsM,graph,dbFlag,saveFig,saveFigRRf,qrsAfs)
%---------------------------------------------------------------------------------------------
% Fecg: Fetal QRS detection
% - For each ECG channel:
% - Fetal QRS pre-detection
% - Identification of a good interval
% - Fetal QRS detection in forward direction starting from the beginning
% and in backward starting from the end of such a interval
% - Best fetal QRS detection selection based on fetal RR variability and
% fetal-mother QRS position coincidence
% --------------------------------------------------------------------------------------------
% Author: Maurizio Varanini, Clinical Physiology Institute, CNR, Pisa, Italy
% For any comment or bug report, please send e-mail to: maurizio.varanini@ifc.cnr.it
% --------------------------------------------------------------------------------------------
% This program is free software; you can redistribute it and/or modify it under the terms
% of the GNU General Public License as published by the Free Software Foundation; either
% version 2 of the License, or (at your option) any later version.
%
% This program is distributed "as is" and "as available" in the hope that it will be useful,
% but WITHOUT ANY WARRANTY of any kind; without even the implied warranty of MERCHANTABILITY
% or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
% --------------------------------------------------------------------------------------------
if(nargin<3), cName=''; end
if(nargin<4), qrsM=[]; end
if(nargin<5), graph=1; end
if(nargin<6), dbFlag=0; end
if(nargin<7), saveFig=0; end
if(nargin<8), saveFigRRf=0; end
if(nargin<9), qrsAfs=0; end
fprintf('\n --------------------------------------------------------- \n');
[progpath, progname] = fileparts(which(mfilename));
fprintf('Program: %s, record name: %s\n', progname, cName);
if(saveFig), figFmt='png';
figPath=fullfile('../Figure/',progname);
if(~exist(figPath,'dir')), mkdir(figPath); end
end
if(~isempty(qrsAfs));
learning=1; % learning set, annotations are available
else
learning=0; %test set
end
%-------------------------------------------------------------
% recording duration
[ndt, ns]=size(X);
vtime= [1:ndt]/fs;
if(dbFlag && learning), PlotSgnMrkNc(X, qrsAfs*fs, fs, [cName,': faQRS']); end
% -----
if(dbFlag), PlotSgnMrkNc(X, qrsM, fs, [cName,': mQRS']); end
qrsMs=qrsM/fs;
%--------------------------------------------------------------------------------------------
for is=1:ns,
X(:,is)= (X(:,is)-mean(X(:,is)))/std(X(:,is));
end
% X(:,ns+1)= mean(X')'; % if ICA fails S/N improvment could be obtained
% ns=ns+1;
if(graph)
figure, set(gcf,'Color','white');
for is=1:ns,
subplot(ns,1,is), plot(vtime,X(:,is));
wgmi1= min(X(:,is)) -2;
wgma1= max(X(:,is)) +2;
ylim([wgmi1, wgma1]);
set(gca,'YTick',[-5 0 5])
% if(is~=ns), set(gca,'XTickLabel',''); end
if(is==1), title([cName,': ICA fetal ECG']); end
end
end
ecg=X;
% raw derivative filter coefficients
% 5ms before and after, 3ms in the middle
nu=ceil(0.005 * fs); nz=floor(0.0030*fs /2)*2 +1; % nz=nearest odd value
B=[ones(nu,1);zeros(nz,1);-ones(nu,1)];
delay=floor(length(B)/2);
% --- compute the derivative signal
ecgfx=[repmat(ecg(1,:),delay,1);ecg;repmat(ecg(end,:),delay,1)];
decgr=filter(B,1,ecgfx); decgr= decgr(2*delay+1:end,:);
if(dbFlag)
figure; freqz(B,1,1000,fs);
end
% ----- Butterworth forward and backward bandpass filtered (1-6Hz)
fmind=0.7; fmaxd=8;
Wn = [fmind, fmaxd]/(fs/2); % normalized cut-off frequency (0,1)
[b,a]= butter(1,Wn);
decgBp=filtfilt(b,a,decgr);
% ----- absolute derivative ------
adecg=abs(decgr);
if(graph)
figure, set(gcf,'Color','white');
wgmima= mimaxscG(adecg,0,0,0.1);
for is=1:ns,
subplot(ns,1,is), plot(vtime,adecg(:,is));
ylim(wgmima);
% if(is~=ns), set(gca,'XTickLabel',''); end
if(is==1), title([cName,': ECG absolute derivative']); end
end
end
% ----- Butterworth forward and backward bandpass filtered (1-6Hz)
fmind=0.7; fmaxd=8;
Wn = [fmind, fmaxd]/(fs/2); % normalized cut-off frequency (0,1)
[b,a]= butter(1,Wn);
adecgBp=filtfilt(b,a,adecg);
if(graph)
figure, set(gcf,'Color','white');
wgmima= mimaxscG(adecgBp(fs:end-fs),0,0,0.1);
for is=1:ns,
subplot(ns,1,is), plot(vtime,adecgBp(:,is));
ylim(wgmima);
% if(is~=ns), set(gca,'XTickLabel',''); end
if(is==1), title([cName,': ECG filtered absolute derivative']); end
end
end
% ----
if(learning), nQRSaf=length(qrsAfs);
fprintf('Number of annotated fetal QRSs= %d\n', nQRSaf);
RRafs= diff(qrsAfs); % annotated fetal RR
end
RRmc= diff(qrsM); RRms= RRmc/fs; % detected mother RR
%
% -------------------------------------------------------------------------------
qrsFs=cell(1,ns);
RRfs=cell(1,ns);
for ic=1:ns,
% ----
xic=X(:,ic);
ecgic=ecg(:,ic);
decgic=decgr(:,ic);
decgBpic=decgBp(:,ic);
adecgic=adecg(:,ic);
adecgBpic=adecgBp(:,ic);
if(dbFlag && learning), PlotSgnMrkNc(xic, qrsAfs*fs, fs, [cName,' - eS']); end
% ---- QRS detection (first step) ---------------------------------------------
% qrsM=QRSdetectorQeA2T(vadx,vdx,fs,pth,RRts,pmQT)
pth=0.35; qrsFp1=QRSdetectorF1(adecgBpic,decgic,fs,pth,0.45,0.8);
%
if(dbFlag), fprintf('Number of pre-detected fetal QRSs= %d\n', length(qrsFp1)); end
RRfc1= diff(qrsFp1); RRfs1= RRfc1/fs; % predetected fetal RR
if(graph)
figure, set(gcf,'Color','white'); hold on;
plot(qrsMs, [RRms(1);RRms],'m.-');
if(learning), plot(qrsAfs, [RRafs(1);RRafs],'b.-'); end
plot(qrsFp1/fs, [RRfs1(1);RRfs1],'r.-'); ylim([0.1, 1]);
if(learning), title([cName,': detected mother(m), annotated (b) & pre-detected(r) fetal RR series']);
else title([cName,': detected mother (m) & pre-detected fetal(r) RR series']); end
figResize(0, 1, 1, .35);
end
% ---- Identification of a "good" RR interval ----
% [nb,vp]=hist(RRfs,[0.25:0.05:0.9]);
RRfsc1=sort(RRfs1); RRfsc1=RRfsc1(round(0.05*length(RRfsc1)):round(0.95*length(RRfsc1)));
[nb,vp]=hist(RRfsc1);
if(graph)
figure, bar(vp,nb,1); title([cName,': pre-detected RR hist']);
end
[nbm,ibm]=max(nb); RRst=vp(ibm); % most frequent value
adRR=abs(diff(RRfs1));
adRRx=[repmat(adRR(1),2,1);adRR;repmat(adRR(end),2,1)];
%adRRx=medfilt1(adRRx,5);
mvadRR=filter(ones(1,5),1,adRRx); mvadRR= mvadRR(2*2+1:end,:);
if(graph), figure, plot(qrsFp1(3:end)/fs,mvadRR); end
thad=0.4;
RRoklen=0;
while(~RRoklen)
for j=1:4
isRRok=[]; ieRRok=[];
jint=1; RRokFlag=0;
for i=1:length(mvadRR)
if(RRst-0.1<RRfs1(i) && RRfs1(i)<RRst+0.1 && mvadRR(i)<thad)
if(~RRokFlag), RRokFlag=1; isRRok(jint)=i; else ieRRok(jint)=i; end
else
if(RRokFlag), ieRRok(jint)=i; jint=jint+1; RRokFlag=0; end
end
end
if(RRokFlag), ieRRok(jint)=i+1; RRokFlag=0; end
if(isempty(isRRok)), RRoklen=0;
else [RRoklen,im]=max(ieRRok-isRRok);
end
if(RRoklen>5), break; end
thad=thad+0.1;
end
end
RRsmi=mean(RRfs1(isRRok(im):ieRRok(im)));
iqis=qrsFp1(isRRok(im)); iqie=qrsFp1(ieRRok(im));
sgnOklens=(iqie-iqis)/fs;
% --- Fetal QRS detection in backward direction starting from the end
% of the identified "good" RR interval
pth=0.2; qrsFb=QRSdetectorF2(adecgBpic(iqie:-1:1),decgic(iqie:-1:1),fs,pth,RRst,RRsmi,sgnOklens,1); % backward
qrsFb=iqie-qrsFb(end:-1:1);
% --- Fetal QRS detection in forward direction starting from the beginning
% of the identified "good" RR interval
pth=0.2; qrsFf=QRSdetectorF2(adecgBpic(iqis:end),decgic(iqis:end),fs,pth,RRst,RRsmi,sgnOklens,0); % forward
qrsFf=iqis+qrsFf;
if(isempty(qrsFb))
qrsFic=qrsFf;
elseif(isempty(qrsFf))
qrsFic=qrsFb;
else
ibe=min(find(qrsFb>qrsFf(1)-0.5*RRst*fs));
ifs=min(find(qrsFf>qrsFb(ibe)+0.5*RRst*fs));
qrsFic=[qrsFb(1:ibe); qrsFf(ifs:end)];
end
nQRSdf=length(qrsFic);
if(dbFlag), fprintf('Channel=%d, number of detected fetal QRSs= %d\n', ic, nQRSdf); end
qrsFsic=qrsFic/fs;
RRfsic= diff(qrsFsic); % detected fetal RR
[nb,vp]=hist(RRfsic,[0.25:0.05:0.9]);
if(graph)
figure, bar(vp,nb,1); title([cName,': detected RR hist']);
end
[nbm,ibm]=max(nb); RRst=vp(ibm);
RRfmean=meansc(RRfsic,4,4);
%RfRmean= mean(RRfsic);
RRfstd= std(RRfsic);
if(dbFlag), fprintf('fetal RR mean= %d, stdev=%d\n', RRfmean, RRfstd); end
debugQRS=1;
if(dbFlag && debugQRS)
figure
subplot(2,1,1),plot(adecgic,'b'); title([cName,': filter absolute derivative']);
DrawVertMarker(qrsFic,'r',':','none');
% DrawVertMarker(qrsF(2,:)','b',':','none');
% DrawVertMarker(qrsF(end,:)','r',':','none');
subplot(2,1,2),plot(ecgic(:,1),'b'); title('ecg signal');
DrawVertMarker(qrsFic,'r',':','none');
% DrawVertMarker(qrsF(2,:)','b',':','none');
% DrawVertMarker(qrsF(end,:)','r',':','none');
end
if(graph || saveFig)
if(graph), figure; else figure('visible','off'); end
set(gcf,'Color','white'); hold on;
plot(qrsMs, [RRms(1);RRms],'m.-');
if(learning), plot(qrsAfs, [RRafs(1);RRafs],'b.-'); end
plot(qrsFsic, [RRfsic(1);RRfsic],'r.-');
ylim([0.1, 1]);
if(learning), title([cName,': ic=',num2str(ic),', detected mother(m), annotated (b) & detected(r) fetal RR series']);
else title([cName,': ic=',num2str(ic),', detected mother (m) & fetal(r) RR series']); end
figResize(0, 1, 1, .35);
if(saveFigRRf), figFmtRR='png';
figPathRR='../Figure/';
if(~exist(figPathRR,'dir')), mkdir(figPathRR); end
figName=fullfile(figPathRR,[cName,'_',num2str(ic),'_RRfetal']);
print(gcf, ['-d',figFmtRR],figName);
end
end
qrsFs{ic}=qrsFsic;
RRfs{ic}=RRfsic;
end
% -----------------------------------------------------------------------------
% --- Choosing the best fetal RR series and QRS detection
% based on fetal RR variability and fetal-mother QRS position coincidence
cfact=zeros(ns,1); meRR=zeros(ns,1);
madRR = zeros(ns,1); maddRR=zeros(ns,1); % rmssd = zeros(ns,1);
cFMsim=zeros(ns,1); chanIqf=zeros(ns,1);
for ic=1:ns,
meRR(ic) = median(RRfs{ic});
if(meRR(ic)<0.35), cfact(ic)=0.3*(0.35-meRR(ic));
elseif(meRR(ic)>0.5), cfact(ic)=0.05*(meRR(ic)-0.5);
else cfact(ic)=0;
end
dRRfs=diff(RRfs{ic}); ddRRfs=diff(dRRfs);
madRR(ic) = meansc(abs(dRRfs),0,5);
maddRR(ic) = meansc(abs(ddRRfs),0,5);
%rmssd(ic) = std(diff(RRfs{ic}));
%dRRfsz=dRRfs-mean(dRRfs); rmssd(ic) = sqrt(meansc(dRRfsz.*dRRfsz,0,8));
cmpRes=QRSdet_Ann_cmp(qrsFs{ic},qrsMs, 0.1, 0);
%FMsim(ic)=cmpRes.nTP/(cmpRes.nFP+cmpRes.nFN);
cFMsim(ic)=0.05*cmpRes.nTP/(0.05*cmpRes.nTP+cmpRes.nFP+cmpRes.nFN);
fprintf('channel=%1d, meRR=%7.4f, madRR=%7.4f, maddRR=%7.4f, cfact=%7.4f, cFMsim=%7.4f\n', ...
ic, meRR(ic), madRR(ic),maddRR(ic),cfact(ic),cFMsim(ic));
chanIqf(ic)=madRR(ic)+maddRR(ic)+cfact(ic)+cFMsim(ic);
end
for ic=1:ns,
fprintf('channel=%1d, chanIqf=%7.4f\n', ic, chanIqf(ic));
end
[dummy,icsV]=sort(chanIqf); % select the best channel
ics=icsV(1);
fprintf('Selected channel=%1d\n', ics);
qrsFes=qrsFs{ics};
RRfes=RRfs{ics};
% xs=X(:,ics);
ecgs=ecg(:,ics);
% decgs=decgr(:,ics);
% adecgs=adecg(:,ics);
if(graph)
figure, set(gcf,'Color','white');
for is=1:ns,
subplot(ns,1,is), plot(vtime, X(:,is));
wgmi1= min(X(:,is)) -2;
wgma1= max(X(:,is)) +2;
ylim([wgmi1, wgma1]);
set(gca,'YTick',[-5 0 5])
% if(is~=ns), set(gca,'XTickLabel',''); end
if(is==1), title([cName,': sorted fetal ECG']); end
shg
end
end
% -----------------------------------------------------------------------------
% if(dbFlag) PlotSgnMrkNc(ecgs, qrsFes, fs, cName); end
if(learning && graph), PlotSgnMrkNc(ecgs, {qrsAfs*fs,qrsFes}, fs, [cName,': fecg, ann.(m) & det.(b) qrs']); end
if(saveFig)
figName=fullfile(figPath,[cName,'_ECGfetal']);
print(gcf, ['-d',figFmt],figName);
end
if(graph || saveFig)
figure, set(gcf,'Color','white');
for is=1:ns,
subplot(ns,1,is), plot(vtime, X(:,is));
wgmi1= min(X(:,is)) -2;
wgma1= max(X(:,is)) +2;
ylim([wgmi1, wgma1]);
% DrawVertLines(vtime', qrsF(1,:)/fs, 'r', ylim);
if(learning), DrawVertMarker(qrsAfs,'k',':','+'); end
DrawVertMarker(qrsFes,'r',':','none');
set(gca,'YTick',[-5 0 5])
% if(is~=ns), set(gca,'XTickLabel',''); end
if(is==1)
if(learning), title([cName,': annotated (k) detected (r) fetal qrs']);
else title([cName,': detected (r) fetal qrs']); end
end
end
shg
if(saveFig)
figName=fullfile(figPath,[cName,'_fetal']);
print(gcf, ['-d',figFmt],figName);
end
end
%-------------------------------------------------------------
if(graph || saveFigRRf)
if(graph), figure; else figure('visible','off'); end
set(gcf,'Color','white'); hold on;
plot(qrsMs, [RRms(1);RRms],'m.-');
if(learning), plot(qrsAfs, [RRafs(1);RRafs],'b.-'); end
plot(qrsFes, [RRfes(1);RRfes],'r.-');
ylim([0.1, 1]);
if(learning), title([cName,': detected mother(m), annotated (b) & detected(r) fetal RR series']);
else title([cName,': detected mother (m) & fetal(r) RR series']); end
figResize(0, 1, 1, .35);
if(saveFigRRf), figFmtRR='png';
figPathRR='../FigureRRf/';
if(~exist(figPathRR,'dir')), mkdir(figPathRR); end
figName=fullfile(figPathRR,[cName,'_RRfetal']);
print(gcf, ['-d',figFmtRR],figName);
end
end
end %== function ================================================================