(a) 
(b) 
(c) 
(d) 
  
Processing, correlation, histogramming in parallel. In each case 
the lower left window is the autocorrelation in x and y for the 
windowed image (see text) and the right one the histogram peak 
for the entire image. 
Original image with correlation window towards lower right. 
-4 -8 -4 
Fig (a) processed with kernel € 2 = . 
Fig. (a) subtracted from itself with a 2 pixel diagonal shift. 
Correlation window is slightly below center. 2 
-12 14 -12 
Fig. (a) processed with kernel 4 4 -12 : 
-12 -14 -12 
correlation window as in (c). 
97