[ITK-users] Resample and Directions in Image Registration

[Matt McCormick]

Hi Gabriel,

> In the munual (version 4.6) of ITK it is mentioned about ResamplingFilter
> (page 129):
>
> *"Probably the most important thing to keep in mind when resampling images
> is that the transform
> is used to map points from the output image space into the input image
> space."*
>
> This mean that the parameters are passed to filter mapped points from the
> output image to the input image, right?

Correct.

> Then in the chapter about registration mentioned (page 174) :
>
> *"The Transform that is optimized in the ITK registration framework is the
> one that maps points
> from the physical space of the fixed image into the physical space of the
> moving image"*
>
> This indicates that the transformation parameters mapped points from the
> fixed image to moving image ( In the example ”Hello World Registration" this
> is observed ), right ?

Yes. These are consistent. The resampled output image is sampled on
the grid of points in physical space where the fixed image is sampled.

HTH,
Matt