Hi, is there any tool can linearly transform a tck file with a tranformation matrix, as the " tcktransform" needs an image warp
A workaround is to create a linear warp from a linear transform.
Assuming you have a target space image
target.mif and an affine transformation
A.txt, you can create a warp
wi_Ai.mif that does the same as applying
$ cat A.txt 1 0 0 50 0 1 0 0 0 0 1 0 # create an identity warp $ warpinit image.mif wi.mif # either transform the identity warp to obtain the affine warp `wi_Ai.mif` $ mrtransform wi.mif -linear A.txt wi_Ai.mif -template target.mif -interp linear -nan # or compose warp and linear transform: # $ transformcompose wi.mif A.txt wi_Ai.mif -template target.mif # check that warp and transformation are equivalent: # apply the warp $ mrtransform image.mif -warp wi_Ai.mif image_warped.mif # directly use the linear transformation: $ mrtransform image.mif -linear A.txt image_transformed.mif -template target.mif $ mrview image_warped.mif image_transformed.mif
Note that the direction and reference space for warps applied to images and to track files are different. See here for more information.
For clarity, this is a bit of a feature hole at the moment that we will hopefully rectify. I had this functionality implemented a long time ago, but in an exceptionally large feature development branch that is well and truly incomplete, and hence it never made it to the public release.