bionic (1) AverageAffineTransform.1.gz

NAME

       AverageAffineTransform - part of ANTS registration suite

DESCRIPTION

       AverageAffineTransform   ImageDimension  output_affine_transform  [-R  reference_affine_transform]  {[-i]
       affine_transform_txt [weight(=1)] ]}

              Usage: Compute weighted average of input affine transforms.

       For 2D and 3D transform, the affine transform is first decomposed into scale x shearing x rotation.  Then
       these  parameters  are  averaged,  using  the  weights  if  they provided. For 3D transform, the rotation
       component is the quaternion. After averaging, the quaternion will also be normalized to have  unit  norm.
       For  2D  transform,  the  rotation  component  is  the rotation angle. The weight for each transform is a
       non-negative number. The sum of all weights will be normalized to 1 before averaging. The  default  value
       for each weight is 1.0.

       All  affine  transforms  is a "centerd" transform, following ITK convention. A reference_affine_transform
       defines the center for the output transform. The  first  provided  transform  is  the  default  reference
       transform Output affine transform is a MatrixOffsetBaseTransform.

       -i option takes the inverse of the affine mapping.

              For example: 2 output_affine.txt -R A.txt A1.txt 1.0 -i A2.txt 2.0 A3.txt A4.txt 6.0 A5.txt

       This computes: (1*A1 + 2*(A2)^-1 + A3 + A4*6 + A5 ) / (1+2+1+6+5)