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Table of Contents....................................................................................................................................... 1ZERO CROSSING REMOVAL%%%%%% ........................................................................... 2DETECT R_PEAK ............................................................................................................. 2Calculate R in the actual Signal ............................................................................................ 2After R Peak Tracking ... DETCET OTHERS .......................................................................... 3ONSET ............................................................................................................................. 3P Peak .............................................................................................................................. 3Q Detection ....................................................................................................................... 4S Detection ....................................................................................................................... 4T Peak .............................................................................................................................. 5END OF T ........................................................................................................................ 6CASE OF ST SEGMENT ELEVATION ................................................................................ 7

% Load original 1D signal.clc;clear all;close all;ELEVATED=[][fname path]=uigetfile('*.mat');fname=strcat(path,fname);

load(fname ); z=zeros(100,1);

A=val(1,:); v1=val(1,:)-val(1,1); A=v1; A=A'; zc=A(1); A=[z;A;z];

% s = A(1:1:400); s = A;

ls = length(s); figure(1) plot(s); title('Actual Signal'),grid on

[c,l]=wavedec(s,4,'db4'); ca1=appcoef(c,l,'db4',1); ca2=appcoef(c,l,'db4',2); ca3=appcoef(c,l,'db4',3); ca4=appcoef(c,l,'db4',4);

figure(2) plot(c),title('decomposed signal'),grid on figure(3)

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subplot(2,2,1) plot(ca1),title('1st level reconstructed'),grid on subplot(2,2,2) plot(ca2),title('2nd level reconstructed'),grid on subplot(2,2,3) plot(ca3),title('3rd level reconstructed'),grid on subplot(2,2,4) plot(ca4),title('4th level reconstructed'),grid on

Error: File: C:\Users\AbdKabeer\Documents\Msc Tel\DSP\ass\Project\ECG\Very Useful\ECG_FEATURE_WAVELET_ST\FINAL__PHYSIONET_DATA.m Line: 277 Column: 1Illegal use of reserved keyword "end".

ZERO CROSSING REMOVAL%%%%%% base_corrected=ca2; y=base_corrected-zc; figure(4) plot(y),grid on title('base line corrected and smoothed signal')

DETECT R_PEAKy1=y;m1=max(y1)-max(y1)*.60;P=find(y1>=m1);% it will give two two points ... remove one point eachP1=P;P2=[];last=P1(1);P2=[P2 last];for(i=2:1:length(P1)) if(P1(i)>(last+10)) last=P1(i); P2=[P2 last]; endendRt=y1(P2);figure(5)plot(y1),grid on,hold onplot(P2,Rt,'*');

Calculate R in the actual SignalP3=P2*4;Rloc=[];for( i=1:1:length(P3)) range= [P3(i)-20:P3(i)+20]; m=max(A(range)); l=find(A(range)==m); pos=range(l); Rloc=[Rloc pos];endRamp=A(Rloc);

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figure(6)plot(A),grid on,hold onplot(Rloc,Ramp,'*');title('Detected R peak in actual Signal')

After R Peak Tracking ... DETCET OTHERSX=Rloc;y1=A;for(i=1:1:1)

for(j=1:1:length(X))

a=X(j)-100:X(j)-50; m=max(y1(a)); b=find(y1(a)==m); b=b(1); b=a(b);

ONSET fnd=0;for k=b-20:+1:b if((y1(k)<=0) && (y1(k-1)>0)) qon1=k; fnd=1; break endendif(fnd==0)Qrange=b-20:+1:b;qon1=find(y1(Qrange)==max(y1(Qrange)));qon1=Qrange(qon1);endRON(i,j)=qon1(1);fnd;for k=b:+1:b+20 if((y1(k)<=0) && (y1(k-1)>0)) qon1=k; fnd=1; break endendif(fnd==0)Qrange=b:+1:b+20;qon1=find(y1(Qrange)==max(y1(Qrange)));qon1=Qrange(qon1);endROF(i,j)=qon1(1);

P Peak a=Rloc(i,j)-100:Rloc(i,j)-10;

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m=max(y1(a)); b=find(y1(a)==m); b=b(1); b=a(b); Ploc(i,j)=b; Pamp(i,j)=m;

end

Q Detection a=Rloc(i,j)-50:Rloc(i,j)-10; m=min(y1(a)); b=find(y1(a)==m); b=b(1); b=a(b); Qloc(i,j)=b; Qamp(i,j)=m; %%%%% ONSET fnd=0;for k=b-20:+1:b if((y1(k)<=0) && (y1(k-1)>0)) qon1=k; fnd=1; break endendif(fnd==0)Qrange=b-20:+1:b;qon1=find(y1(Qrange)==max(y1(Qrange)));qon1=Qrange(qon1);endQON(i,j)=qon1(1);fnd;for k=b:+1:b+20 if((y1(k)<=0) && (y1(k-1)>0)) qon1=k; fnd=1; break endendif(fnd==0)Qrange=b:+1:b+20;qon1=find(y1(Qrange)==max(y1(Qrange)));qon1=Qrange(qon1);endQOF(i,j)=qon1(1);

S Detection a=Rloc(i,j)+5:Rloc(i,j)+50; m=min(y1(a)); b=find(y1(a)==m);

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b=b(1); b=a(b); Sloc(i,j)=b; Samp(i,j)=m; %%%% onset off fnd=0;for k=b-5:+1:b if((y1(k)<=0) && (y1(k-1)>0)) qon1=k; fnd=1; break endendif(fnd==0)Qrange=b-20:+1:b;qon1=find(y1(Qrange)==max(y1(Qrange)));qon1=Qrange(qon1);endSON(i,j)=qon1(1);fnd=0;for k=b:+1:b+20 if((y1(k)<=0) && (y1(k-1)>0)) qon1=k; fnd=1; break endendif(fnd==0)Qrange=b:+1:b+20;qon1=find(y1(Qrange)==max(y1(Qrange)));qon1=Qrange(qon1);endSOFF(i,j)=qon1(1);

T Peak a=Rloc(i,j)+25:Rloc(i,j)+100; m=max(y1(a)); b=find(y1(a)==m); b=b(1); b=a(b); Tloc(i,j)=b; Tamp(i,j)=m; %%%% onset off fnd=0;for k=b-20:+1:b if((y1(k)<=0) && (y1(k-1)>0)) qon1=k; fnd=1; break endendif(fnd==0)

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Qrange=b-20:+1:b;qon1=find(y1(Qrange)==max(y1(Qrange)));qon1=Qrange(qon1);endTON(j,i)=qon1(1);fnd=0;for k=b:+1:b+20 if((y1(k)<=0) && (y1(k-1)>0)) qon1=k; fnd=1; break endendif(fnd==0)Qrange=b:+1:b+20;qon1=find(y1(Qrange)==max(y1(Qrange)));qon1=Qrange(qon1);endTOFF(j,i)=qon1(1);

if(Tamp(i,j)<Pamp(i,j)) a=Rloc(i,j)+25:Rloc(i,j)+70; m=min(y1(a)); b=find(y1(a)==m); b=b(1); b=a(b); Tloc(i,j)=b; Tamp(i,j)=m; ELEVATED=[ELEVATED j];

end

END OF Tendendfigure;k=1;for(i=1:1:1) %subplot(6,1,k);

plot(y1), hold on; plot(Rloc(i,:),Ramp(i,:),'*'),hold on; plot(Qloc(i,:),Qamp(i,:),'+'),hold on; plot(Sloc(i,:),Samp(i,:),'+'),hold on; plot(Ploc(i,:),Pamp(i,:),'.'), hold on plot(Tloc(i,:),Tamp(i,:),'^') grid on; k=k+1; if(k>6) k=1; figure; end

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end

clc;flag=0;if(length(ELEVATED)>ceil(.8*length(Rloc))) disp('T inverted (MI Detected) with T inverted Logic') return;else

flag=1;end

CASE OF ST SEGMENT ELEVATIONx=A;TOFF=TOFF';TON=TON';for(i=1:1:1)

for(j=1:1:length(Rloc(i,:)) )PRpoint(i,j)= ceil(Rloc(i,j)-(SOFF(i,j)-QON(i,j))/2);STpoint(i,j)=ceil(Tloc(i,j)-(TOFF(i,j)-TON(i,j))/2);STDeviation(i,j)=abs(x(PRpoint(i,j),i)-x(STpoint(i,j),i)); endendx=STDeviation/100;x=mean(x);if(x>1) disp('MI Detected')else disp('Normal Signal')end

Published with MATLAB® 7.14