SPM ignores the orient and data_history fields in the .hdr files. We
were were also not sure about what the various fields were used for.
The fields that you need to be compatible with SPM99b are explained
in the help pages on "Data Format". More information is also available
by taking a look at spm_hread.m.
Also note that there is normally a left-right flip at the spatial
normalisation stage (unless you modify the defaults), so the spatially
normalised images are not strictly in an Analyze compatible orientation.
I hope this helps,
-John
| I am quite novice using SPM and first of all I am trying to implement a
| conversion tool from our
| own image format to Analyze format.
| Does anyone know where can I find some precise information about this format
| and especially concerning the
| flag "orient" in the "data_history" structure of the header file.
|
| How are the follwing values of this flag related to the reference coordinate
| system ?:
|
| Values of the flag "orient' :
| 0 transverse unflipped
| 1 coronal unflipped
| 2 sagittal unflipped
| 3 transeverse flipped
| 4 coronal flipped
| 5 sagittal fliiped
|
| The reference coordinate system given by the Mayo Foundation is :
|
| X : Right -> Left
| Y : Back -> Front
| Z : Feet -> Head
|
|
|
| ^ ^ Y
| Z \ |
| \ |
| \ |
| \ |
| \ |
| --------> X
| 0
|
|
| I did not manage to find such information even on the Mayo Foundation
| WebSite
|
| Can anyone tell me how this flag is used by SPM in order to display data
| (especially if it is different from zero)
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