AFNI is changing the signe of an image center

AFNI version=AFNI_24.2.01 (Jul 16 2024) [64-bit]

Dear AFNI experts, 

I recently had a problem with function such as 3drefit or 3dvolreg changing the sign of my image center. Here is an exemple with 3dinfo```

> 3dinfo sub-Roshan_ses-9_task-rest_run-01_bold.nii.gz
> 
> Template Space:  ORIG
> Dataset Type:    Echo Planar (-epan)
> Byte Order:      LSB_FIRST {assumed} [this CPU native = LSB_FIRST]
> Storage Mode:    NIFTI
> Storage Space:   183,500,800 (184 million) bytes
> Geometry String: "MATRIX(2,0,0,-63.14847,0,2,0,-27.77728,0,0,2,18.2975):64,64,32"
> Data Axes Tilt:  Plumb
> Data Axes Orientation:
>   first  (x) = Right-to-Left
>   second (y) = Anterior-to-Posterior
>   third  (z) = Inferior-to-Superior   [-orient RAI]
> R-to-L extent:   -63.148 [R] -to-    62.852 [L] -step-     2.000 mm [ 64 voxels]
> A-to-P extent:   -27.777 [A] -to-    98.223 [P] -step-     2.000 mm [ 64 voxels]
> I-to-S extent:    18.297 [S] -to-    80.298 [S] -step-     2.000 mm [ 32 voxels]
> Number of time steps = 700  Time step = 0.70000s  Origin = 0.00000s  Number time-offset slices = 32  Thickness = 2.000
>   -- At sub-brick #0 '?' datum type is short:            0 to         14935
>   -- At sub-brick #1 '?' datum type is short:            0 to         14473
>   -- At sub-brick #2 '?' datum type is short:            0 to         14689
> ** For info on all 700 sub-bricks, use '3dinfo -verb' **
> 
> 
> 3drefit -orient RAI sub-Roshan_ses-9_task-rest_run-01_bold.nii.gz
> 3dinfo sub-Roshan_ses-9_task-rest_run-01_bold.nii.gz
> 
> 
> Template Space:  ORIG
> Dataset Type:    Echo Planar (-epan)
> Byte Order:      LSB_FIRST {assumed} [this CPU native = LSB_FIRST]
> Storage Mode:    NIFTI
> Storage Space:   183,500,800 (184 million) bytes
> Geometry String: "MATRIX(2,0,0,-63.14847,0,2,0,-27.77728,0,0,2,-18.2975):64,64,32"
> Data Axes Tilt:  Plumb
> Data Axes Orientation:
>   first  (x) = Right-to-Left
>   second (y) = Anterior-to-Posterior
>   third  (z) = Inferior-to-Superior   [-orient RAI]
> R-to-L extent:   -63.148 [R] -to-    62.852 [L] -step-     2.000 mm [ 64 voxels]
> A-to-P extent:   -27.777 [A] -to-    98.223 [P] -step-     2.000 mm [ 64 voxels]
> I-to-S extent:   -18.297 [I] -to-    43.702 [S] -step-     2.000 mm [ 32 voxels]
> Number of time steps = 700  Time step = 0.70000s  Origin = 0.00000s  Number time-offset slices = 32  Thickness = 2.000
>   -- At sub-brick #0 '?' datum type is short:            0 to         14935
>   -- At sub-brick #1 '?' datum type is short:            0 to         14473
>   -- At sub-brick #2 '?' datum type is short:            0 to         14689
> ** For info on all 700 sub-bricks, use '3dinfo -verb' **

Note the change in I from 18 to -18
tks for your help

Howdy-

Well, it isn't a random change. 3drefit will change header info.

What are you aiming to do?

--pt

Hey Paul,
you are right, it seems that -oblique_origin keep the center with 3drefit,
however, why is 3dvolreg changing the center?
I am applying several transformations on different images, fMRI, anat
My pipeline keep the center in the anat, and change it with the fMRI images which result in miss alignment
Clément

Glad you have a process for the reorientation. What is the problem with the 3dvolreg output? What is the command and the input?