We developed a new pulse sequence and investigated whether the anisotropic diffusion in the human brain can be detailed with a standard whole-body MR imager. Apparent diffusion coefficient maps were produced by the proposed sequence using a 1.5-T MR unit. The sequence employed simultaneous application of three orthogonal gradients to achieve an optimal signal attenuation for imaging the brain w...

The enhanced backscattering cone displaying a strong anisotropy from a material with anisotropic diffusion is reported. The constructive interference of the wave is preserved in the helicity preserving polarization channel and completely lost in the nonpreserving one. The internal reflectivity at the interface modifies the width of the backscatter cone. The reflectivity coefficient is measured ...

In this paper, we present a new color image regularization method using a rotating smoothing filter. This approach combines a pixel classification method, which roughly determines if a pixel belongs to a homogenous region or an edge with an anisotropic perceptual edge detector capable of computing two precise diffusion directions. Using a now classical formulation, image regularization is here ...

1 Key Laboratory of Land Resources Evaluation andMonitoring in Southwest (Sichuan Normal University), Ministry of Education, Chengdu 610066, China 2 School of Computer Science, Sichuan Normal University, Chengdu 610066, China 3 School of Automation Engineering, University of Electronic Science and Technology of China, Chengdu 610054, China 4 Institute of Medical Information and Technology, Scho...

bilateral filtering, anisotropic diffusion, adaptive smoothing, denoising Bilateral filtering has recently been proposed as a noniterative alternative to anisotropic diffusion. In both these approaches, images are smoothed while edges are preserved. Unlike anisotropic diffusion, bilateral filtering does not involve the solution of partial differential equations and can be implemented in a singl...

Diffusion processes driven by anisotropic diffusion tensors are known to be well-suited for structure-preserving denoising. However, numerical implementations based on finite differences introduce unwanted blurring artifacts that deteriorate these favourable filtering properties. In this paper we introduce a novel discretisation of a fairly general class of anisotropic diffusion processes on a ...

This paper describes a partial differential equation for denoising images. The proposed method is demonstrably superior to anisotropic diffusion (and it’s many variations) for denoising images that are approximately piecewise constant. The method relies on an equation that is the level-set equivalent of the anisotropic diffusion equation proposed by Perona and Malik [1]. This proposed equation ...

Anisotropic diffusion methods are well-known to give good qualitative results for image denoising. This paper gives a review of the anisotropic diffusion methodology and its application to image denoising. We propose a fixed-point iteration using a multigrid solver to solve a regularized anisotropic diffusion equation, which is not only well-posed, but also has a nontrivial steady-state solutio...

This paper is dedicated to a new anisotropic diffusion approach for image regularization based on a gradient and two diffusion directions obtained from half Gaussian kernels. This approach results in smoothing an image while preserving edges. From an anisotropic edge detector, built of half Gaussian derivative kernels, we introduce a new smoothing method preserving structures which drives the d...

Nonlinear anisotropic diffusion filtering is a procedure based on nonlinear evolution partial differential equations which seeks to improve images qualitatively by removing noise while preserving details and even enhancing edges. However, well known implementations are sensitive to parameters which are necessarily tuned to sharpen a narrow range of edge slopes; otherwise, edges are either blurr...