Part of ants registration suite
ComposeMultiTransform ImageDimension output_field [-R reference_image] {[deformation_field | [-i] affine_transform_txt ]}
Usage has the same form as WarpImageMultiTransform
For Example:
ComposeMultiTransform Dimension outwarp.nii -R template.nii ExistingWarp.nii ExistingAffine.nii
or for an inverse mapping :
ComposeMultiTransform Dimension outwarp.nii -R template.nii -i ExistingAffine.nii ExistingInverseWarp.nii
recalling that the -i option takes the inverse of the affine mapping
Or: to compose multiple affine text file into one: ComposeMultiTransform ImageDimension output_affine_txt [-R reference_affine_txt] {[-i] affine_transform_txt} This will be evoked if a text file is given as the second parameter. In this case reference_affine_txt is used to define the center of the output affine. The default reference is the first given affine text file. This ignores all non-txt files among the following parameters.