Mike,
Yes, qdec in v4 can be used to process v3 data. There is a difference between v4 fsaverage and v3 fsaverage, but recon-all -qcache will use whatever is named fsaverage in your $SUBJECTS_DIR, so as long as you have your chosen fsaverage in the subjects dir, then that is the one it will use. Or, you can use the -target option following -qcache to specify another average subject. The recon-all -help has a section on - qcache.
qdec doesnt use the atlases, so you dont need to worry about those.
Nick
On Thu, 2007-12-20 at 11:17 -0600, Michael Harms wrote:
Hello, We are getting ready to do some surface analyses on data processed under v3.0.4 or v3.0.5. We would like to try using the Qdec utility from FS v4 to analyze this v3 data. Is that a legitimate thing to do?
I see that at a minimum, we will need to run recon-all -s <subj> -qcache (under FS v4) to generate necessary files expected by Qdec.
The various surfaces for the 'fsaverage' subject differ between v4 and v3. Obviously, running -qcache under v4 will use the v4 'fsaverage' subject. Provided we then also link to the v4 'fsaverage' subject for display purposes, I'm assuming that we'll be in proper correspondence. Is that correct?
v3 and v4 also have different .gca and .gcs atlases. But I don't need to worry about that in terms of using Qdec, right?
Is there anything else I'm missing that would need to be done, or why Qdec (v4) can't be used on v3 processed data?
thanks, Mike H.