Can Anyone help me with the source of comparing histograms of images using Chi-Square Distance?? I searched online i got but it is giving me zero distance reagardless of histograms are same or not. I.e. Matching or not matching.. Please help me.

function d=chi_square_statistics(XI,XJ) % Implementation of the Chi^2 distance to use with pdist % (cf. "The Earth Movers' Distance as a Metric for Image Retrieval", % Y. Rubner, C. Tomasi, L.J. Guibas, 2000) % % @author: B. Schauerte % @date: 2009 % @url: http://cvhci.anthropomatik.kit.edu/~bschauer/

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m=size(XJ,1); % number of samples of p
p=size(XI,2); % dimension of samples

%assert(p == size(XJ,2)); % equal dimensions
%assert(size(XI,1) == 1); % pdist requires XI to be a single sample

d=zeros(m,1); % initialize output array

for i=1:m
  for j=1:p
    m=(XI(1,j) + XJ(i,j)) / 2;
      if m ~= 0 % if m == 0, then xi and xj are both 0 ... this way we avoid the problem with (xj - m)^2 / m = (0 - 0)^2 / 0 = 0 / 0 = ?
        d(i,1) = d(i,1) + ((XI(1,j) - m)^2 / m); % XJ is the model! makes it possible to determine each "likelihood" that XI was drawn from each of the models in XJ
      end
  end
end

[radha]

Please Tell me what should I do so that I can differentiate when histograms are matching and not matching?? Because It gives me zero distance for both so I have no idea how should go ahead?? Thanks in advance... Please help me as soon as possible..

[radha]

I am Using Mat Lab R2011a version.