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Topic: How to calculate the angle between two images?
Replies: 41   Last Post: Dec 8, 2012 11:02 PM

 Messages: [ Previous | Next ]
 khoo Posts: 63 Registered: 8/9/08
Re: How to calculate the angle between two images?
Posted: Apr 5, 2009 1:59 PM

> 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??

Date Subject Author
4/3/09 khoo
4/3/09 Dave Robinson
4/3/09 khoo
4/3/09 Dave Robinson
4/3/09 khoo
4/3/09 Dave Robinson
4/3/09 khoo
4/3/09 khoo
4/4/09 khoo
4/4/09 Dave Robinson
4/4/09 khoo
4/4/09 khoo
4/5/09 khoo
4/5/09 Dave Robinson
4/5/09 khoo
4/5/09 khoo
4/5/09 Dave Robinson
4/5/09 khoo
4/6/09 khoo
4/6/09 Dave Robinson
4/6/09 khoo
4/6/09 Dave Robinson
4/6/09 khoo
4/6/09 Dave Robinson
4/6/09 khoo
4/6/09 khoo
4/6/09 khoo
4/7/09 khoo
4/7/09 khoo
4/7/09 Dave Robinson
12/8/12 Jeff
4/3/09 Skeptic
4/3/09 Dave Robinson
4/3/09 Roger Stafford
4/3/09 khoo
4/3/09 Roger Stafford
4/3/09 ImageAnalyst
4/3/09 khoo
4/4/09 khoo
4/6/09 Matt
4/6/09 khoo
4/6/09 Matt