fsz = [9 9];
fmid = ceil((fsz+1)/2);
imsz = [16 16];

% pick one:
im = eye(imsz);
im = mkRamp(imsz,pi/6); 
im = mkSquare(imsz,6,pi/6); 

% pick one:
edges='reflect1';
edges='reflect2';
edges='repeat';
edges='extend';
edges='zero';
edges='circular';
edges='dont-compute';

filt = mkImpulse(fsz,[1 1]);
showIm(corrDn(im,filt,edges));
line([0,0,imsz(2),imsz(2),0]+fmid(2)-0.5, ...
     [0,imsz(1),imsz(1),0,0]+fmid(1)-0.5);
title(sprintf('Edges = %s',edges));

%%% Multi-scale pyramids (see pyramids.m for more exam