A HighlyEffective Approach for Generating Delaunay Mesh Models of RGB Color Images A highly effective method for generating Delaunay mesh models of RGB (i.e., redgreenblue) color images, known as CMG, is proposed. This method builds on ideas from the previouslyproposed GPRFSED method of Adams for grayscale images to produce a method that can handle RGB color images. The key ideas embodied in our CMG method are FloydSteinberg error diffusion with improved initialcondition selection and greedypoint removal. Through experimental results, our CMG method is shown to outperform several competing methods that are based on a straightforward extension of grayscale mesh generators to color, with our method yielding meshes of vastly better quality at lower or comparable computationalmemory cost.

HLO: Halfkernel Laplacian operator for surface smoothing Abstract   This paper presents a simple yet effective and efficientw method for featurepreserving surface smoothing. Through analyzing the differential property of surfaces, we show that the conventional discrete Laplacian operator with uniform weights is not applicable to feature points at which the surface is nondifferentiable and the second order derivatives do not exist. To overcome this difficulty, we propose a Halfkernel Laplacian Operator (HLO) as an alternative to the conventional Laplacian. Given a vertex    v   , HLO first finds all pairs of its neighboring vertices and divides each pair into two subsets (called half windows); then computes the uniform Laplacians of all such subsets and subsequently projects the computed Laplacians to the fullwindow uniform Laplacian to alleviate flipping and degeneration. The half window with least regularization energy is then chosen for    v   . We develop an iterative approach to apply HLO for surface denoising. Our method is conceptually simple and easy to use because it has a single parameter, i.e., the number of iterations for updating vertices. We show that our method can preserve features better than the popular uniform Laplacianbased denoising and it significantly alleviates the shrinkage artifact. Extensive experimental results demonstrate that HLO is better than or comparable to stateoftheart techniques both qualitatively and quantitatively and that it is particularly good at handling meshes with high noise. Also, it outperforms all other compared methods in terms of computational time. We make our executable program publicly available.