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finvspline

$ \bigcirc$Name


finvspline 2D inverse B-spline transform




$ \bigcirc$Command Synopsis


finvspline in order out



in : input (Fimage)

order : spline order (2..11)

out : output (Fimage of coefficients)




$ \bigcirc$Function Summary


void finvspline (in , order , out )

Fimage in , out ;

int order ;




$ \bigcirc$Description


This modules computes the inverse B-spline transform of a two-dimensionnal array of numbers (Fimage). A mirror extension is used at the boundaries of the array. The coefficients out(k, l ) are computed in order to ensure that the B-spline interpolation

u(x, y) = $\displaystyle \sum_{{k,l}}^{}$out(k, l )  $\displaystyle \beta^{n}_{}$(x - k$\displaystyle \beta^{n}_{}$(y - l )

satisfies u(k, l )= in(k, l ). The spline $ \beta^{n}_{}$ is defined in the documentation of fcrop module. The order of the spline n (order) must be between 2 and 11. The module is based on a recursive implementation of the associated z-filter (see [TBU99][UAE91]).




$ \bigcirc$See Also


fcrop, fproj, funzoom.


$ \bigcirc$Version 1.0


Last Modification date : Thu Nov 29 20:23:56 2001


$ \bigcirc$Author


Lionel Moisan






next up previous contents index
Next: flocal_zoom Up: Reference Previous: fextract   Contents   Index
mw 2004-05-05