get orientation of image from meta data

[YingdiZhang]

Thanks for the great job!
I wonder how to get the orientation of a *.nii file , like RAS or LPI.
I have get the meta information refering to #3727, but dont found the orientation information in the meta data

[rijobro]

If you have the affine transformation matrix (e.g., data["image_meta_dict"]["affine"]), you can get the orientation with this:

affine = np.eye(4)  # or e.g., data["image_meta_dict"]["affine"]
print("".join(nib.aff2axcodes(affine)))

This is the relevant bit of code in our transform: https://github.com/Project-MONAI/MONAI/blob/dev/monai/transforms/spatial/array.py#L531.