Image registration using b-splines

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Here is my question: My optical system is made of a camera plus a circular plexiglass "lens" that changes its curvature depending on pressure (radial bending).

This curvature induces a deformation of the image captured by the camera. To correct this deformation, images need to be calibrated. Calibration can be made with a grid (chessboard, dots, lines), pressure range has to be discretized with a certain step. For each pressure step, an image of the grid has to be taken. Then each image has to be compared to the reference one (P=0), and a transformation matrix has to be computed and stored. Finally, each image taken during the experiment for a specific pressure has to be corrected by the transformation matrix.

The deformation is non-linear (not only a combination of rotations and translations), but most likely Barrel distortion. (again not induced by the camera) Which looks like that: http://en.wikipedia.org/wiki/Distorti...

I found a plugin in ImageJ called BunwarpJ, http://biocomp.cnb.csic.es/~iarganda/...

and I basically want to know if there is an equivalent way to produce the same result in Opencv.