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Dear AFNI users-

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Sincerely, AFNI HQ

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Zhang Yu
September 28, 2018 09:52AM
Hi AFNI experts,
The dicom files in my fMRI experiment were transformed into the .nii format by MRIconvert firstly before preprocessing.
I found some fields in the .nii files generated by different versions of MRIconvert are different, though the inputted data are exactly the same. 
nifti_tool -diff_hdr -infiles ver1.nii ver2.nii
  name                offset  nvals  values
  ------------------- ------  -----  ------
  datatype              70      1    4
  datatype              70      1    512
  pixdim                76      8    -1.0 1.5 1.5 1.49995 2.0 0.0 0.0 0.0
  pixdim                76      8    1.0 1.5 1.5 1.49995 4.0 0.0 0.0 0.0
  slice_duration       132      1    0.0762
  slice_duration       132      1    0.05
  quatern_b            256      1    -0.005177
  quatern_b            256      1    0.030369
  quatern_c            260      1    -0.985187
  quatern_c            260      1    0.168696
  quatern_d            264      1    0.168696
  quatern_d            264      1    0.985187
  qoffset_y            272      1    -77.154175
  qoffset_y            272      1    102.401825
  qoffset_z            276      1    2.340701
  qoffset_z            276      1    -61.537697

The files ver1.nii and ver2.nii are generated by the different version of MRIconvert with the same data inputted.
Whether these fields with the different values can affect the results of some steps in preprocessing in afni?
For example, whether the difference in the values of the field 'slice_duration' can change the 3dTshift results?
Thank you in advance!
Yu



Edited 2 time(s). Last edit at 10/02/2018 01:33AM by Zhang Yu.
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Subject Author Posted

Can the wrong values in these fields of NIFTI files affect the preprocessing results in AFNI?

Zhang Yu September 28, 2018 09:52AM

Re: Can the wrong values in these fields of NIFTI files affect the preprocessing results in AFNI?

rick reynolds October 04, 2018 06:54PM

Re: Can the wrong values in these fields of NIFTI files affect the preprocessing results in AFNI?

Zhang Yu October 06, 2018 05:03AM

Re: Can the wrong values in these fields of NIFTI files affect the preprocessing results in AFNI?

rick reynolds October 11, 2018 09:15AM