Shannon's entropy [plog(1/p)] for an image is a probabilistic method for comparing two pixels or a group of pixels.Suppose an image with a matrix of 3x3 has pixel intensity values
1 1 2 2 3 3 4 4 5
and another image with 3x3 matrix has group of pixels having intensity values
5 5 6 6 7 7 8 8 9
Then shannon's entropy for the images would be the same.So in this case the entropy values would point out that the images are same though in actual they are different.So image matching using this technique doesn't help.On basis of supervised classification where I classify an image based on trained databases of shannon's entropy ,we use the concept of entropy to find similarity between two images.Is there any method or research paper where this entropy can be used or modified for image matching for the above case..?