www.pudn.com > HMM1.zip > histCmpChi2.m~


function d = histCmpChi2(h1, h2)
> Compare two histograms using chi-squared
> function d = histCmpChi2(h1, h2)
>
> d(i,j) = chi^2(h1(i,:), h2(j,:)) = sum_b (h1(i,b)-h2(j,b)^2 / (h1(i,b) + h2(j,b))

[N B] = size(h1);
d = zeros(N,N);
for i=1:N
h1i = repmat(h1(i,:), N, 1);
numer = (h1i - h2).^2;
denom = h1i + h2;
d(i,:) = numer ./ denom;
end