Re: what is metric for distance between images ?

asdf wrote:

> Can anybody tell me the metric used for getting the distance between
> two grayscale images that are x by y length and width in pixels with
> greyscale values between 0-255 ? I'm particularily interested in the
> metric used by the simple fractal compression schemes ...

You can use the naive Euclidean distance or, even more usefully, the shuffle
distance, which is robust to small, localised deformations. We used the
shuffle distance in work on evaluating models and assessing registration:

http://www2.wiau.man.ac.uk/caws/Conferences/26/online_proceedings/papers/paper-53-263.html
(IPMI 2005)

http://www.schestowitz.com/Research/Papers/2005/Assessing_Registration/HTML/

If you exploit compression schemes, you can probably apply similar methods
to the coefficients used in reconstruction, treating them as points in
hyperspace.

Roy
.