Thanks for a prompt reply. The command takes ~16 minutes per hemisphere in my setting. Are those realistic numbers or is it longer than it should take?

mri_surf2surf --s fsaverage --hemi rh --sval /d/drive/workspace/brainbrowser/examples/models/rh.sig.mgh --trgsubject ICBM2009c_fs6 --tval /tmp/out.mgh

sysname  Linux
hostname 36ddc1c5be86
machine  x86_64
user     root
srcsubject = fsaverage
srcval     = /d/drive/workspace/brainbrowser/examples/models/rh.sig.mgh
srctype    =
trgsubject = ICBM2009c_fs6
trgval     = /tmp/out.mgh
trgtype    =
srcsurfreg = sphere.reg
trgsurfreg = sphere.reg
srchemi    = rh
trghemi    = rh
frame      = 0
fwhm-in    = 0
fwhm-out   = 0
label-src  = (null)
label-trg  = (null)
OKToRevFaceOrder  = 1
UseDualHemi = 0
Reading source surface reg /opt/freesurfer/subjects/fsaverage/surf/rh.sphere.reg
Loading source data
Reading target surface reg /opt/freesurfer/subjects/ICBM2009c_fs6/surf/rh.sphere.reg
Done
Using surf2surf_nnfr()
Mapping Source Volume onto Source Subject Surface
surf2surf_nnfr: building source hash (res=16).
Surf2Surf: Forward Loop (157000)

surf2surf_nnfr: building target hash (res=16).
Surf2Surf: Reverse Loop (163842)
Reverse Loop had 117731 hits
Surf2Surf: Dividing by number of hits (157000)
INFO: nSrcLost = 0
nTrg121 = 152424, nTrgMulti =  4576, MnTrgMultiHits = 26.7279
nSrc121 = 133857, nSrcLost =     0, nSrcMulti = 29985, MnSrcMultiHits = 4.69815
Saving target data
Saving to /tmp/out.mgh

real    16m25.129s
user    16m24.160s
sys     0m0.260s

On Thu, Nov 10, 2016 at 11:40 AM, Douglas N Greve <greve@nmr.mgh.harvard.edu> wrote:
Years ago I used to have code that would cache this transform, but we
abandoned it because it would get out of synch whenever someone updated
their recon, and, for ordinary apps, it does not take that much time.


On 11/10/2016 02:13 PM, Chris Filo Gorgolewski wrote:
> Thanks for a quick reply. I'm actually in a situation where I do not
> have all of the overlays at the same time so I cannot concatenate them.
>
> To put more contexts: I am building surface support into neurovault.
> When someone uploads a surface statistical map I want to automatically
> calculate a projection of this map into MNI volume. To improve the MNI
> volume surface mapping I have reconstructed the surface of the
> 2009c_asym_nlin template. For every incoming map I am doing
> fsaverage -> MNI2009c mri_surf2surf followed by mri_surf2vol. However,
> the mri_surf2surf takes quite a bit of time to run and most of it is
> spend on coregistration - which is always the same. If only I could
> calculate the coregistration once and apply it to every incoming map
> it would speed things up tremendously.
>
> Let me know if you have any ideas.
>
> Best,
> Chris
>
> On Thu, Nov 10, 2016 at 10:26 AM, Douglas N Greve
> <greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>> wrote:
>
>     You can use mri_concat to create a stack of overlays, then
>     mri_surf2surf
>     the entire stack, then split the stack.
>
>
>     On 11/10/2016 12:28 AM, Chris Filo Gorgolewski wrote:
>     > Hi,
>     > I need to convert a big number of scalar surface maps from fsaverage
>     > to one particular subject space. This means running mri_surf2surf
>     > command many times. For each execution the same transformation is
>     > calculated and then applied. Since estimating the transformation
>     take
>     > a substantial amount of time I was wondering if I could
>     calculate the
>     > transformation once and just apply it (which is a common thing in
>     > volumetric registration). I perused the website and the command line
>     > options, but I could not find anything. Is it possible to save and
>     > reuse surface transformations?
>     >
>     > Best,
>     > Chris
>     >
>     >
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>     --
>     Douglas N. Greve, Ph.D.
>     MGH-NMR Center
>     greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>
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>
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--
Douglas N. Greve, Ph.D.
MGH-NMR Center
greve@nmr.mgh.harvard.edu
Phone Number: 617-724-2358
Fax: 617-726-7422

Bugs: surfer.nmr.mgh.harvard.edu/fswiki/BugReporting
FileDrop: https://gate.nmr.mgh.harvard.edu/filedrop2
www.nmr.mgh.harvard.edu/facility/filedrop/index.html
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