One of the limitations of the Demons algorithm is that it can neither handle large deformation nor generate diffeomorphic spatial transformations which are required for the shape analysis in the framework of Computational Anatomy. We proposed to replace the addition of freeform deformation in the Demons’ update step by a few compositions of deformation fields using group exponential. The algorithm proved to be computationally efficient. Our experiments showed that this new algorithm was capable of recovering large deformation and is diffeomorphic with similar results of the Demons algorithm. The generated deformation were smooth and invertible in terms of Jacobian with much lower energy of the deformation fields.
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