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Topic: Image rotation detection probelm
Replies: 32   Last Post: Aug 8, 2013 10:46 PM

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 Kev Posts: 2 Registered: 12/20/12
Re: Image rotation detection probelm
Posted: Dec 20, 2012 10:17 PM

Hi Phillip,

Thanks for replying. I do not get the part on correct registration. Say if I have an image of the letter 'A' rotated. I try to do a xcorr of the polar transform of this image with the image of the letter 'A' upright. The peak of the xcorr will be higher than xcorr of a letter 'B' with 'A' right?

K
"Phillip" wrote in message <kb03n6\$n63\$1@newscl01ah.mathworks.com>...
> It's true that for a given pair of images the cross correlation peak will be higher when they are registered correctly. But it is possible for one pair to have a higher peak than another pair even if the latter is better aligned - it all depends on the images. In other words, the value at the peak is not directly comparable across image pairs (unless the image pairs all have quite similar spatial content).
>
> "Kev " <piakster@gmail.com> wrote in message <kau56h\$9p7\$1@newscl01ah.mathworks.com>...

> > This solution is super useful for my application. I am basically working on an feature tracking/pattern recognition application and my method has to be rotation and intensity invariant. So one question is that will I get a higher xcorr peak if the 2 images are matching compared to none matching ones?
> >
> > Cheers,
> > K

Date Subject Author
6/19/09 Matt
8/2/10 Phillip
12/21/10 chee ali
12/21/10 Phillip
12/21/10 Matt J
12/21/10 Phillip
11/14/12 Darren g
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2/6/13 Darren g
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