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From: "khoo" <jim_khoo@hotmail.com>
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Subject: Re: How to calculate the angle between two images?
Date: Sun, 5 Apr 2009 17:59:01 +0000 (UTC)
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> Why on earth are you trying to convert an image into a 1 dimensional vector? you are correlating 2 histograms - histograms are essentially  graphs - in your case angle along the x axis, number of pixels of that angle in y direction. If you have say 256 angles, then each bin represents (2*pi)/256 radians. Thus the histogram will be a vector of 256 numbers, each number representing the number of pixels of that angle.
> 
> I suggest you carefully read help hist(), doesn't that default to 10 bins - you will need to have much better resolution than that.
> 
> I have had a look at your images, and would have thought they were ideally suited to this methodology.
> 
> Regards
> 
> Dave Robinson

bro Dave, i no understand what you explain..can u explain in more detail??i get the angle is very large..is around 250k..how can like that?? how i need to take the the max angle rotation from the corr graph??