A comment on "A novel approach for the registration of weak affine images"

In the recent paper (Li and Zhang, 2012) a mapping model of weak affine transform (WAT) was proposed for registering images of flat scenes. We show that such a model may cause inaccuracies when registering images with non-uniform scaling differences, even if they seemingly behave according to this model. Mathematical reason of this is that WAT is neither invertible nor closed. We explain why mapping models forming a group should be preferably used for registration and show some examples of models belonging to affine subgroups.

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[2]  Yunhua Zhang,et al.  A novel approach for the registration of weak affine images , 2012, Pattern Recognit. Lett..

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