Fast adaptive elliptical filtering using box splines

We demonstrate that it is possible to filter an image with an elliptic window of varying size, elongation and orientation with a fixed computational cost per pixel. Our method involves the application of a suitable global pre-integrator followed by a pointwise-adaptive localization mesh. We present the basic theory for the 1D case using a B-spline formalism and then appropriately extend it to 2D using radially-uniform box splines. The size and ellipticity of these radially-uniform box splines is adaptively controlled. Moreover, they converge to Gaussians as the order increases. Finally, we present a fast and practical directional filtering algorithm that has the capability of adapting to the local image features.

• Type: Conference
• Year: 2008
• Where: ICIP
• Authors: Arrate Muñoz-Barrutia, Kunal Narayan Chaudhury, Michael Unser
• Keywords: B-spline Formalism, Directional Filtering Algorithm, ICIP 2008, Image Processing, Local Image Features, Pointwise-adaptive Localization Mesh, Radially-uniform Box Splines