global str2num;
global med_u_sub;
global med_v_sub;
global x_min;
global x_max;
global y_min;
global y_max;
a= str2num{1,1};
b= str2num{1,2};
imagea = imread(a);
imageb = imread(b);
interrogationarea = app.windowsizeEditField.Value;
xmin = x_min + interrogationarea/2+1; % 33
xmax = x_max - (interrogationarea/2+1); % 3840-(64/2+1)=3807 . (732)
ymin = y_min + interrogationarea/2+1 ; %33
ymax = y_max - (interrogationarea/2+1); % 2160-(64/2+1)=2127 . (991)
imagea=padarray(imagea,[ceil(interrogationarea/2) ceil(interrogationarea/2)], min(min(imagea)));
imageb=padarray(imageb,[ceil(interrogationarea/2) ceil(interrogationarea/2)], min(min(imageb)));
clear u v
jj=0;
ii=0;
step = 0.5*interrogationarea;
if (rem(interrogationarea,2) == 0) %for the subpixel displacement measurement
SubPixOffset=1;
else
SubPixOffset=0.5;
end
for J=xmin:step:xmax
jj=1+jj;
ii=1;
for I=ymin:step:ymax
ii=1+ii;
test_ima=imagea(J:J+interrogationarea-1, I:I+interrogationarea-1);
test_imb=imageb(ceil(J-0.5*interrogationarea):ceil(J+1.5*interrogationarea-1), ceil(I-interrogationarea/2):ceil(I+1.5*interrogationarea-1));
test_ima=test_ima-mean(mean(test_ima)); %64*64->1*64->1*1
test_imb=test_imb-mean(mean(test_imb));
correlation = normxcorr2(test_ima,test_imb);
%An error occurred using: coder.internal.errorIf The values of TEMPLATE cannot all be equal.
%I don't understand this part
[ypeak xpeak] = find(correlation==max(correlation(:)));
centerx = ceil(size(correlation,1)/2);
centery = ceil(size(correlation,2)/2);
u(jj,ii)= max(xpeak) - centerx-SubPixOffset;
v(jj,ii)= max(ypeak) - centery-SubPixOffset;
[vector] = SUBPIX2DGAUSS(correlation, interrogationarea, xpeak, ypeak, SubPixOffset);
u_sub(jj,ii)= sqrt(vector(1)*conj(vector(1))) - centerx;
v_sub(jj,ii)= sqrt(vector(2)*conj(vector(2))) - centery;
end
end
