Re: [caret-users] info in the deformation maps

2017-10-20 Thread Harwell, John
Hello, You are correct, it is not an affine matrix. A description of the file’s content is available at http://brainvis.wustl.edu/CaretHelpAccount/caret5_help/file_formats/file_formats.html#deformationMapFile. Essentially, the deformation map file defines a resampling of one surface

Re: [caret-users] info in the deformation maps

2017-10-20 Thread David Van Essen
Hi Tony et al. John’s explanation regarding deformation map files is correct. Here, I’m drawing to your attention the fact that Connectome Workbench (and wb_command) provides improved methods for mapping from one surface mesh that has been registered to another (see below). Depending on your

Re: [caret-users] info in the deformation maps

2017-10-20 Thread Matt Glasser
Also Connectome Workbench has some more advanced methods of quantifying isotropic and anisotropic registration induced distortion. Peace, Matt. From: on behalf of Timothy Coalson Reply-To: "Caret, SureFit, and SuMS software users"

Re: [caret-users] info in the deformation maps

2017-10-20 Thread Timothy Coalson
A small addendum: spherical surface registration is not the only use for measuring surface distortion. If you use it on resampled anatomical surfaces from different longitudinal timepoints, or from different species, or just different subjects, you can get a measure of the difference in

Re: [caret-users] info in the deformation maps

2017-10-20 Thread Matt Glasser
It¹s also worth noting that in Connectome Workbench we moved away from the deformation map file as it enforces a particular resampling of the data as well (not just a data transformation). Instead we use the deformed and target spheres to store the registration and this allows for choice in

Re: [caret-users] info in the deformation maps

2017-10-20 Thread tony han
Hi John and David, Thanks a lot for your reply! Yes I'm thinking to move from Caret to Workbench since most of the time we use wb_command a lot and it makes sense to keep our tools up-to-date and consistent. Just want to clarify: the weights (last 3 columns) of the vertices (indexed by the

Re: [caret-users] info in the deformation maps

2017-10-20 Thread Timothy Coalson
Deformation maps are inherently designed for the purpose of going from one topology (number of triangles and their layout) to a different one, so they are a tricky thing to try to compare vertexwise. They also don't really encode warpfield deformations (and even using them to reconstruct as much