problem with correlation of two images

my code is :

{function [ cofficient ] = Untitled( image )

 I = imread('D:\\Thesis Code\\Source Code\\StegoImage.png');

 J=imread('D:\\Thesis Code\\Source Code\\RotatedImage.png');

 corr2(I,J)

end }

I got the problem like..

Error using corr2>ParseInputs (line 40)

A and B must be the same size.

Error in corr2 (line 22)

[a,b] = ParseInputs(varargin{:});

Error in Untitled (line 7)

 corr2(I,J)
how can i solve this problem ?? plz help

Answer 1

[Image Analyst]

The correlation will be bad if one of the images is a rotated version of the other, so don't even bother. If you want to detect if one is a scaled, translated, and rotated version of the other, try Hu's moments like in this video