vanvliet: Young-Van Vliet recursive Gaussian filter.

In imager: Image Processing Library Based on 'CImg'

Young-Van Vliet recursive Gaussian filter.

Description

The Young-van Vliet filter is a fast approximation to a Gaussian filter (order = 0), or Gaussian derivatives (order = 1 or 2).

Usage

vanvliet(im, sigma, order = 0L, axis = "x", neumann = FALSE)

Arguments

im	an image
sigma	standard deviation of the Gaussian filter
order	the order of the filter 0,1,2,3
axis	Axis along which the filter is computed. One of 'x', 'y', 'z', 'c'
neumann	If true, use Neumann boundary conditions (default false, Dirichlet)

References

From: I.T. Young, L.J. van Vliet, M. van Ginkel, Recursive Gabor filtering. IEEE Trans. Sig. Proc., vol. 50, pp. 2799-2805, 2002. (this is an improvement over Young-Van Vliet, Sig. Proc. 44, 1995)

Boundary conditions (only for order 0) using Triggs matrix, from B. Triggs and M. Sdika. Boundary conditions for Young-van Vliet recursive filtering. IEEE Trans. Signal Processing, vol. 54, pp. 2365-2367, 2006.

Examples

vanvliet(boats,sigma=2,order=0) %>% plot("Zeroth-order Young-van Vliet along x")
vanvliet(boats,sigma=2,order=1) %>% plot("First-order Young-van Vliet along x")
vanvliet(boats,sigma=2,order=1) %>% plot("Second-order Young-van Vliet along x")
vanvliet(boats,sigma=2,order=1,axis="y") %>% plot("Second-order Young-van Vliet along y")

imager documentation built on May 29, 2024, 1:38 a.m.