Although HOG is mainly used to detect local distortion, it is also fit for FF because FF is a local distortion appearing on random area in an image.
Wu, "Full-reference image quality assessment by combining global and local distortion measures," Signal Processing, vol.
As is known, in image or appearance-based approaches such as conventional PCA, if there is severe local distortion
such as partial occlusion in the object image, which is not usually existed in the training images, the performance of the classifier will drop down rapidly.
The "perfect" cartogram, says Dorling, would be one that also minimizes local distortion
. "If you were to look in detail at a very small area of the cartogram, it should look very similar to a normal map," he says.
The researchers showed that the webs also cause local distortions
in the Earth's electric field since they behave like conducting discs.
The use of modelled winds makes the results virtually independent of local distortions
of winds at ground measurement sites which are frequently quite large at coastal observation sites in the Baltic Sea (Keevallik 2003; Soomere & Keevallik 2003).
Surface flaws are picked up by a camera as local distortions
in the curved stripes.
Connections may look similar and may fit, but they could also cause local distortions
and stress concentrations beyond the design stress.
Pinpointing that distance makes it possible to more accurately measure, for example, the position of spiral density waves -- local distortions
in the main rings that orbit in sync with Saturn;s moons outside the rings.