2004 年 58 巻 1 号 p. 115-120
An anisotropic extension is presented to a bilateral filter which is an edge-preserving nonlinear filter. Spatially anisotropic weights are adjusted on the basis of the gradient tensor of the luminance at each pixel of an image. This anisotropic bilateral filter is applied to enhance stripe patterns such as fingerprints and nonphotorealistic rendering for generating flow patterns in pictures. Extension of the low-pass characteristics to a band-pass ones strengthens the stripe enhancement effect of the filter.