normxcorr2

% imoffset.m

% Calculate image offset

% by Xiaozhou

imagefile='image-';

% Region for comparison

xc1=10;

yc1=10;

xc2=90;

yc2=90;

width=xc2-xc1+1;

height=yc2-yc1+1;

% images serial no.

istart=1;

iend=50;

iref=50;                            % use the last image as the reference

nim=iend-istart+1;

% initial offset

offx=zeros(1,nim);

offy=zeros(1,nim);

imref=imread([imagefile num2str(iref,'%03d') '.tif']);

region0=imref(yc1:yc2,xc1:xc2);

for i=1:nim

    im=imread([imagefile num2str(i+istart-1,'%03d') '.tif']);

    region=im(((yc1-20):(yc2+20)),((xc1-20):(xc2+20)));

    imcorr=normxcorr2(region0,region);

    [corrmax,imax]=max(imcorr(:));

    [ypeak, xpeak] = ind2sub(size(imcorr),imax);

    offx(i)=offx(i)+xpeak-width-20;

    offy(i)=offy(i)+ypeak-height-20;

end