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Description

his fit an distortion of type

         pixel undistorted = pixel distorted(k0 + k1*r + k2*r*r + k3*r*r*r + k4*r*r*r*r)

the model can be made to work on any lines present in and image although the current tool uses a presented grid pattern

We are only considering radial not tangential - as the later is said to be neglegable
Best result at typically found by having the software calculate the even terms k2 amd k4 and this line up with Optical theory which shows that this polynomial should only feature even powers. However many graphic packages seem to use k1 and k3 (adobe? and image magick)

k0 typical is set to 1-k1-k2-k3-k4 (in normalized coordiantes this preserves size)

Based on the papers
Straight Lines Have to Be Straight
Automatic Calibration and Removal of Distortion from Scenes of Structured Environments
Frederic Devernay, Olivier Faugeras


Correcting Lens Distortions in Digital Photographs
Wolfgang Hugemann

Settings

Inverse Method

NOTE the revert (inverse) has two option __footer__