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

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 Dave Robinson Posts: 1,338 Registered: 1/25/05
Re: How to calculate the angle between two images?
Posted: Apr 6, 2009 10:32 AM

"khoo" <jim_khoo@hotmail.com> wrote in message <grd1c5\$mk8\$1@fred.mathworks.com>...
> > Had you considered that the results just might be right? Think about it - when you rotated the image, do the the actual image boundaries rotate?. You had some almost circular details toward the centre of the image, rotating a circle will generate exactly the same angle image irrespective of the amount of twist. If your image contains aliasing (digital stepping in the image), these will always generate detail usually at 0 and 90 degrees. Remember that your x scale needs to be rescaled such that 0 -> 256 actually maps to 0 ->360 degrees.
> >
> > Meanwhile do the other spikes bear any relationship to the actual rotation angle between your images?
> >
> > If the zero degree spike offends you why not set it to zero - if you know that the two images do have a valid rotation
> >
> > Regards
> >
> > Dave Robinson

>
> Bro Dave, when i rotate the images, i don't think the actual image boundaries will rotate...ABout the other spikes bear, i no sure about it but how to set the zero degree spike to zero??

im8(0) = 0;

Maybe

Regards

Dave Robinson

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
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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