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Bug 349 - don't understand a few lines in ft_volumerealign

Reported 2011-01-03 10:05:00 +0100
Modified 2011-05-05 21:24:30 +0200
Product: FieldTrip
Component: core
Version: unspecified
Hardware: PC
Operating System: Mac OS
Importance: P3 normal
Assigned to: Robert Oostenveld
Depends on:
See also:

Jan-Mathijs Schoffelen - 2011-01-03 10:05:58 +0100

prior to calling headcoordinates in ft_volumerealign (headcoordinates computes the transformation matrix going from voxel space to head space) the nas/lpa/rpa voxels are warped according to the transform present in the input mri. (ll 267 and beyond). This is a bit odd, because if the initial transform already contains a voxel2head transformation, then the lpa/rpa/nas will be defined in head-coordinates rather than voxel coordinates and the resulting matrix realign will transform from one headspace into another headspace. Then, later on, the final transform is computed by: realign * mri.transform, where realign is the output of headcoordinates. This should then 'undo' the initial warp of lpa/rpa/nas, because the resulting transformation matrix goes from voxel to original headspace to new headspace. Is this the correct interpretation?

Robert Oostenveld - 2011-04-15 09:49:06 +0200

is het inzicht ondertussen gekomen? kan deze bug gesloten worden?

Jan-Mathijs Schoffelen - 2011-04-15 09:57:07 +0200

ja, ik geloof het wel. sluit deze maar af.

Robert Oostenveld - 2011-05-05 21:24:30 +0200

bulk action: closed all bugs with status "resolved/fixed"