1D spatio-temporal correlation

oneD_STICS.m

clear all

%% READ IMAGE FROM FILE

I=imread('kymo.bmp');

%maximum delay time (in frames)
nMaxTime = 60;


imheight=size(I,1); %time
imwidth=size(I,2); %space


I=double(I);


nTotLineXC=NaN(2*imwidth+1,nMaxTime);
%deltat
for dt=0:nMaxTime  
    %include negative
    
    %for dx=0:(imwidth-1)
    for dx=(1-imwidth):(imwidth-1)
        dMeanxx=0;
        dMeanxy=0;
        dCount=0;
        for t=1:(imheight-dt)
            %let's define min and max
            if(dx>=0)
                imin=1;
                imax=(imwidth-dx);
            else
                imin=1-dx;
                imax=imwidth;
            end
            %for(i=1:(imwidth-dx))
            for(i=imin:imax)
                dMeanxy = dMeanxy+I(t,i)*I(t+dt,i+dx);
                dMeanxx=dMeanxx + I(t,i);
                dCount=dCount+1;
            end
        end
        dMeanxy=dMeanxy/dCount;
        dMeanxx=dMeanxx/dCount;
        nTotLineXC(dx+imwidth,dt+1)=(dMeanxy/(dMeanxx*dMeanxx))-1;
    end    
end
figure

%limit space correlation length
xrange=(round(imwidth*0.5):round(imwidth*1.5));
%plot
imagesc(nTotLineXC(xrange,:));
axis equal