> On 29 Jul 2015, at 20:57, John Baublitz <jb...@bu.edu> wrote:
> 
> Thank you very much for the support. Unfortunately I have tried using this 
> GIFTI file that it outputs with FreeSurfer as an overlay and surface

Both at the same time?

> and it throws errors for all FreeSurfer utils and even AFNI utils. FreeSurfer 
> mris_convert outputs:
> 
> mriseadGIFTIfile: mris is NULL! found when parsing file f_mvpa_rh.func.gii
> 
> This seems to indicate that it is not saving it as a surface file. Likewise 
> AFNI's gifti_tool outputs:
> 
> ** failed to find coordinate/triangle structs
> 
> How exactly is the data being stored in the GIFTI file? It seems that it is 
> not saving it as triangles and coordinates even based on the code you linked 
> to in the github commit given that the NIFTI intent codes are neither 
> NIFTI_INTENT_POINTSET nor NIFTI_INTENT_TRIANGLE by default.

For your current purposes (visualizing surface-based data), consider there are 
two types of "surface" GIFTI files:

1) "functional" node-data, where each node is associated with the same number 
of values. Examples are time series data or statistical maps. Typical 
extensions are .func.gii or .time.gii.
2) "anatomical" surfaces, that have coordinates in 3D space (with 
NIFTI_INTENT_POINTSET) and node indices in face information (with 
NIFTI_INTENT_TRIANGLE). The typical extension is surf.gii.

In PyMVPA:
(1) "functional" surface data is handled through mvpa2.datasets.gifti. Data is 
stored in a Dataset instance.
(2) "anatomical" surfaces are handled through mvpa2.support.nibabel.surf (for 
GIFTI, mvpa2.support.nibabel.surf_gifti). Vertex coordinates and face indices 
are stored in a Surface instance (from mvpa2.support.nibabel.surf)

(I'm aware that documentation about this distinction can be improved in PyMVPA).

> I've also run into a problem where the dataset that I've loaded has no intent 
> codes and unfortunately it appears that this means that the NIFTI intent code 
> is set to NIFTI_INTENT_NONE.

Why is that a problem? What are you trying to achieve? If the dataset has no 
intent, then NIFTI_INTENT_NONE seems valid to me, as the GIFTI standard 
describes this as "Data intent not specified".


_______________________________________________
Pkg-ExpPsy-PyMVPA mailing list
Pkg-ExpPsy-PyMVPA@lists.alioth.debian.org
http://lists.alioth.debian.org/cgi-bin/mailman/listinfo/pkg-exppsy-pymvpa

Reply via email to