Unfortunately I only have img/hdr files. 


when I put mri_info I have this message:


<color><param>FFFF,0000,0000</param>[ash:14725/mri/orig] wpark% ls

14725.hdr       14725.img

[ash:14725/mri/orig] wpark% mri_info 14725.img 

INFO: analyzeRead(): found 1 files for
/usr/local/freesurfer_package/freesurfer

subjects/14725/mri/orig/14725.img

-----------------------------------------------------------------

INFO: could not find
/usr/local/freesurfer_package/freesurfer/subjects/14725/mr

/orig/14725.mat file for direction cosine info.

INFO: use Analyze 7.5 hdr->hist.orient value: 0, transverse unflipped
(default)

INFO: if not valid, please provide the information in
/usr/local/freesurfer_pac

age/freesurfer/subjects/14725/mri/orig/14725.mat file

-----------------------------------------------------------------

Volume information for 14725.img

          type: analyze3d

    dimensions: 256 x 256 x 124

   voxel sizes: 0.7812, 0.7812, 1.5000

          type: SHORT (4)

           fov: 0.000

        xstart: 0.0, xend: 0.0

        ystart: 0.0, yend: 0.0

        zstart: 0.0, zend: 0.0

            TR: 0.00 msec, TE: 0.00 msec, TI: 0.00 msec, flip angle:
0.00 degre

s

       nframes: 1

ras xform present

    xform info: x_r =  -1.0000, y_r =   0.0000, z_r =   0.0000, c_r =    
0.000

              : x_a =   0.0000, y_a =   1.0000, z_a =   0.0000, c_a =    
0.000

              : x_s =   0.0000, y_s =   0.0000, z_s =   1.0000, c_s =    
0.000

voxel to ras transform:

               -0.7812   0.0000   0.0000   100.0000

                0.0000   0.7812   0.0000  -100.0000

                0.0000   0.0000   1.5000   -93.0000

                0.0000   0.0000   0.0000     1.0000

[ash:14725/mri/orig] wpark% 

</color>

I know that doing mri_convert  -iid x_r x_a x_s -ijd y_r y_a y_s -ikd
z_r z_a z_s I can change the orientation.

In this case it would be 

mri_convert -iid -1 0 0 -ijd 0 1 0 -ikd 0 0 1 14725.img .


My questions: 

1) Are these the "default" values that the mri_convert use if I do not
specify anything? (mri_convert 14725.img .)

2) If I want to change, the possible values are -1 0 and 1?


Thank you very much.


Wan