Lesson 5: Filters as templates

1D correlation

Onion = rgb2gray(imread(‘onion.png’));
Peppers = rgb2gray(imread(‘pepper.png));
imshowpair(peppers, onion, ‘montage’);
C = normxcorr2(onion, peppers);
Figure, surf(c), shading flat;

Positive lays positive, negative line up with the negatives.

Spike => where the two images syncs

Function index = find_template_1D(t,s)
C = normxcorr2(t,s);
[maxValue index] = max(c);
Index = rawIndex - size(t,2) +1;
Endfunction