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Subject: Re: Motion estimation vs. background subtraction
Date: Thu, 13 Mar 2008 13:57:01 +0000 (UTC)
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I might be asking a lot of silly questions now :)

I just want to make sure I got everything right.

Computing the mean pixel intesity is okay, and thereby 
create a new image set as the background.

The sigma on the other hand, I know how to calculate it for 
a set of values, but how to do it for a set of images? Do I 
calculate the std.dev. for a set, in this case with the 
size of 10 values, of pixels containing of all pixels from 
position (1,1), and then do the same with a set of pixels 
from position (1,2) until position (n,m). And then do a 
std.dev. on all of these values again. So in the end I have 
just one value containing the std.dev, or can I do a mean 
of all the std.dev values I get from each pixel-position. 
Hope you understand what I meant here.