Hi,
Yes, this is expected because the Field of View (FOV) of the two images
will be different. In order to have something in common space with a
different resolution you will need to make a reference image that has
both of these characteristics - correct FOV and desired voxel size
(resolution).
To do this the easiest way is to use avwcreatehd to make a new image
with the desired voxel sizes and a FOV equal to or greater than that
of the
original common space image. You will have to work out the number of
voxels so that FOV = number of voxels * voxel size, is set correctly.
Once you've done this and have the new image (check that it is OK in
fslview) then simply use this as the reference image and apply the
transforms in flirt as you have done already.
All the best,
Mark
On 10 Nov 2005, at 18:08, Wayne Lee wrote:
> Hi,
>
> I am in the process of aligning the functional data for a number of
> subjects
> into a common space. However, because I am aligning to a higher
> resolution
> template image, the aligned data has ballooned to occupy a significant
> portion of my harddisks. When applying the transformation matrices
> using
> Flirt, using the original functional data as the reference image
> results in
> a scaled, but truncated output. The superior portion of the brain
> is sliced
> off. Am I rescalling improperly using Flirt? or alternatively, is
> there a
> readily availble tool for rescaling an image?
>
> Thanks for the help!
>
> Wayne
>
>
> --
> Wayne Lee
> Research Assistant
> Rotman Research Institute - Baycrest Centre
> 3560 Bathurst Street
> Toronto, ON M6A 2E1
>
> Tel: (416) 785-2500 x2907
> [log in to unmask]
>
