Dear Freesurfer experts,

I am going to convert the preprocessed surface functional data to volume in fsaverage space so that I can used the processed data in SPM for further analysis, for example, beta series analysis. I tried mri_surf2vol, it worked. But it is time consuming. It takes around 5 minutes per 10 volumes. In addition, the result volume is too big (67MB/ volume for 256*256*256 matrix, 1mm resolution). My data contains about 70800 brain volumes, so the needed time is about 40days and the storage space is about 7TB , which is unacceptable. The code is as follows:

mri_surf2vol --o ${Dir_Subj_fMRI}/$isub/bold/${irun}/Ribbon/${iVolume} --subject fsaverage --so ${SUBJECTS_DIR}/fsaverage/surf/lh.white ${Dir_Subj_fMRI}/$isub/bold/${irun}/LH/${iVolume} --so ${SUBJECTS_DIR}/fsaverage/surf/rh.white ${Dir_Subj_fMRI}/$isub/bold/${irun}/RH/${iVolume}

Are there methods with faster speed and outputing volumes with lower resolution?

Best,

Zhiwei