The way it works is that it goes through each vertex in the label and finds the vertex that is closest on the target surface and assigns that value to that vertex. I think what is happening here is that two of the source vertices are both closest to a single target vertex. In this case, the value of the 2nd/last source vertex gets assigned to the target vertex, meaning that the value of the first source vertex is lost. In order to do what you want, we'd have to assign the first source vertex to a target vertex that it is not closest to (maybe the next closest?). We do not have a way to do that.

On 2/6/19 6:08 PM, Hengda He wrote:

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Hi Freesurfer Developers,

I'm trying to map the vertices of a region (ex. caudal middle frontal) in one subject into the space of another subject (MNI) by using mri_label2label.

I am using the freesurfer_dev/bin/mri_label2label.bin from freesurfer-x86_64-unknown-linux-gnu-dev5-20160513.

For example, I have source Labels (aparc-lh-003_5thCol.label) , which are all in SurfaceRAS coordinates: #!ascii label , from subject FreeSurfer vox2ras=TkReg 8 104996 -35.679 16.281 25.156 1 104997 -36.480 16.439 25.362 2 104998 -37.443 16.702 25.369 3 105705 -41.554 16.840 28.930 4 105716 -40.445 17.153 28.046 5 105720 -39.570 17.200 26.959 6 131017 -29.315 12.915 45.422 7 131030 -31.304 12.514 46.455 8

By running this: /usr/local/freesurfer/freesurfer_dev/bin/mri_label2label.bin --srclabel aparc-lh-003_5thCol.label --srcsubject FreeSurfer --trglabel aparc-lh-003_5thCol_Reg2MNI.label --trgsubject FreeSurferMNI152 --regmethod surface --hemi lh

I got mapped Labels(aparc-lh-003_5thCol_Reg2MNI.label) 119096 -39.670 37.222 12.833 3.0000000000 117433 -44.642 35.253 14.575 4.0000000000 118250 -43.206 35.844 14.273 5.0000000000 119091 -42.114 36.692 14.044 6.0000000000 120517 -26.436 38.614 21.780 7.0000000000 121236 -25.959 39.757 24.739 8.0000000000 121253 -26.213 39.504 23.711 8.0000000000

Could I ask if there is a way to make sure that every vertex in the source '.label' file mapped to one vertex in the target subject space? For example, first two vertex (104996 -35.679 16.281 25.156 1) and (104997 -36.480 16.439 25.362 2) have no corresponded vertex in the target subject space.

Best, Hengda

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