  This paper studies the robustness of SIFT and SURF against different image
transforms (rigid body, similarity, affine and projective) by quantitatively
analyzing the variations in the extent of transformations. Previous studies
have been comparing the two techniques on absolute transformations rather than
the specific amount of deformation caused by the transformation. The paper
establishes an exhaustive empirical analysis of such deformations and matching
capability of SIFT and SURF with variations in matching parameters and the
amount of tolerance. This is helpful in choosing the specific use case for
applying these techniques.
