comparison of two histograms using pdist2

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hi, I am having two Images I wanted compare these two Images by histograms I have read about pdist that provides 'chisq' but i think the way i am doing is not correct, and what to do to show the result afterwards because this is giving a black image.
i1=imread('blue_4.gif');i1=i1(:,:,1);
[c1,n]=imhist(i1);
c1=c1/size(i1,1)/size(i1,2);
i2=imread('blue_5.jpeg');i2=i2(:,:,1);
[c2,n2]=imhist(i2);
c2=c2/size(i2,1)/size(i2,2);
d=pdist2(c1,c2,'chisq');
please give me a working example thanks

Accepted Answer

Anand
Anand on 23 Aug 2013
You almost got it right. Just transpose the histograms. So you're last command should be
d = pdist2(c1',c2');
  8 Comments
Sashank
Sashank on 19 Nov 2017
I am beginner. Please guide me about How can I know how much similar two images are ?
Devarshi Patel
Devarshi Patel on 10 Dec 2018
How can we do this for RGB histogram?

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More Answers (1)

Raghunandan
Raghunandan on 31 Oct 2014
Edited: Raghunandan on 31 Oct 2014
Just wanted to let you know that pdist2 in MATLAB uses 'Euclidean' distance by default. If you are looking to get 'ChiSquare' distance, please use the code found here.
  1 Comment
ndoum ekanga  steve willy
ndoum ekanga steve willy on 27 Nov 2015
Edited: ndoum ekanga steve willy on 27 Nov 2015
But this doesnt give me any output, i cant even see the similarity.
% read two images Im1 = imread('ckt_1.tif'); Im2 = imread('ckt_3.tif');
% convert images to type double (range from from 0 to 1 instead of from 0 to 255) Im1 = im2double(Im1); Im2 = im2double(Im2);
% Calculate the Normalized Histogram of Image 1 and Image 2 hn1 = imhist(Im1)./numel(Im1); hn2 = imhist(Im2)./numel(Im2);
% Calculate the histogram error
f = sum((hn1 - hn2).^2); f; %display the result to console

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