frt2

frt2

skimage.transform.frt2(a) [source]

Compute the 2-dimensional finite radon transform (FRT) for an n x n integer array.

Parameters:	a : array_like A 2-D square n x n integer array.
Returns:	FRT : 2-D ndarray Finite Radon Transform array of (n+1) x n integer coefficients.

See also

ifrt2

The two-dimensional inverse FRT.

Notes

The FRT has a unique inverse if and only if n is prime. [FRT] The idea for this algorithm is due to Vlad Negnevitski.

References

[FRT]

A. Kingston and I. Svalbe, “Projective transforms on periodic discrete image arrays,” in P. Hawkes (Ed), Advances in Imaging and Electron Physics, 139 (2006)

Examples

Generate a test image: Use a prime number for the array dimensions

>>> SIZE = 59
>>> img = np.tri(SIZE, dtype=np.int32)

Apply the Finite Radon Transform:

>>> f = frt2(img)