ifrt2(a)
The FRT has a unique inverse if and only if n is prime. See for an overview. The idea for this algorithm is due to Vlad Negnevitski.
A 2-D (n+1) row x n column integer array.
Inverse Finite Radon Transform array of n x n integer coefficients.
Compute the 2-dimensional inverse finite radon transform (iFRT) for an (n+1) x n integer array.
frt2
The two-dimensional FRT
>>> SIZE = 59
... img = np.tri(SIZE, dtype=np.int32)
Apply the Finite Radon Transform:
This example is valid syntax, but we were not able to check execution>>> f = frt2(img)
Apply the Inverse Finite Radon Transform to recover the input
This example is valid syntax, but we were not able to check execution>>> fi = ifrt2(f)
Check that it's identical to the original
This example is valid syntax, but we were not able to check execution>>> assert len(np.nonzero(img-fi)[0]) == 0See :
The following pages refer to to this document either explicitly or contain code examples using this.
skimage.transform.finite_radon_transform.frt2
skimage.transform.finite_radon_transform.ifrt2
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