Re: Compute the Skewness


Jose Garcia wrote:
> I have to compute the skewness of an image which formula is:
>
> Skeness = (1/D)^3 * SUM^3( V-MEAN(V) )
>
> where D = Standard Deviation
>
> I have read that I have to compute that on the image histogram.
>
> But I need a skeness value for every pixel (not the pixels of lines
in
> the border.. I know).
> So... I think I can calculte it in a 3x3 (or 5x5 maybe) neighborhood.
> Can I do that?
> It is calculated from the historgram or from the pixels gray value
> inside the neighborhood 5x5?
>
> In other words, can somebody explain me how to calculate the skewness
> of an image?


Typically, this is calculated separately for each pixel in the image
(ignoring, as you mentioned, edge effects), by using a surrounding
window.


-Will Dwinnell
http://will.dwinnell.com

.

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