For tie point selection the selection of suitable methods was
basically aiming at rotation invariant procedures as strong
rotation differences in strip and across strip directions are
observed. A scale invariance feature is welcome, but was not absolutely required, as scale differences between neighbouring
photographs are usually rather small. Three methods have been
examined in more detail: SIFT (Scale-invariant Feature
Transform, Lowe, 2010), SURF (Speed up Robust Feature, Bay
et al., 2006) and ORB (Oriented FAST and Rotated BRIEF,
Rublee et al., 2011).