Anisotropic Band-Pass Trilateral Filter for Creating Artistic Painting from Real Image

In this work, we propose a new non-photorealistic rendering approach to the creation of artistic painting from a color image. Our algorithm consists chiefly of two steps: a trilateral filter is firstly applied to the original image for creating drawings vertical to the edges and then a DoG-like band-pass filter is adapted for generating streams along the eigenvectors and therefore smoothes image along stream lines. The proposed trilateral filter in fact is an extension of bilateral filter by considering additional gradient space. On the other hand, DoG-like band-pass filter is computed from eigenvectors and eigenvalues of a tensor matrix calculated at each pixel. Our approach effectively preserves image structures while anisotropically blurring image regions. In regions with low contrast, stream-like structures are also well produced due to gradient relaxation. The experiments demonstrate that the two-steps algorithm can produces good and pleasant visual results.