[Insight-users] Re: Cartesian to polar filter in ITK

[Ali -]

Jakub,Thanks. The transform classes you provide are useful, just a couple of issues:- Why did you use theta = acos(y/x) and not theta = atan(y/x)?- The polar transform is not located at the centre. In order to do so the originmust be set to (-xSize/2, - ySize/2) where (xSize, ySize) is the size of the output image. Setting the origin to any negative value causes a crash withthe provided polar transform.The contribution referenced by Moti will help you to transform image between
cartesian and polar (generally multidimensional cylindrical) coordinates.
You need to use these transforms with ResampleImageFilter to compute the
transformation (see ITK Software Guide section 6.9.4 Resample Image Filter).
Note, that to transform image from cartesian to polar coordinates, you need
to use PolarToCartesianTransform, because ITK is using transforms to map
points from output space to input space. If you have any problems or
questions, feel free to ask me.

Unfortunately, these transforms do only polar mapping. If you need to make
log-polar mapping, i can assist you to write your own transform.

Jakub
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