基于时间变化的鲁棒各向异性扩散模型  

Time Dependent Robust Anisotropic Diffusion Processes

作　　者：王毅[1] 牛瑞卿[1] 喻鑫[1] 沈焕峰[2] 

机构地区：[1]中国地质大学(武汉)地球物理与空间信息学院,武汉430074 [2]武汉大学资源与环境科学学院,武汉430079

出　　处：《自动化学报》2009年第9期1253-1256,共4页Acta Automatica Sinica

基　　金：国家高技术研究发展计划(863计划)(2007AA12Z160);国家自然科学基金(40672205);对地观测技术国家测绘局重点实验室资助项目(200809);测绘遥感信息工程国家重点实验室资助项目(09R02)资助~~

摘　　要：建立性能稳定的扩散模型一直以来都是各向异性扩敞技术研究的关键问题.尽管许多改进的扩散模型陆续提出,这些方法仍旧难以有效解决两个核心问题:梯度阈值和迭代停止时间的确定.针对以上问题,本文提出了基于时间变化的鲁棒各向异性扩散模型.在该模型中,作者设定高斯尺度因子和梯度阈值随时间单调递减,这有利于在多个尺度下准确提取边缘和边界特征信息.此外,利用逐次迭代信噪比能够有效地确定迭代停止时间,减少不必要的过量平滑.为了验证本文模型的有效性,采用Pinecone灰度图像进行了图像增强平滑处理.实验结果表明,本文模型在性能上优于传统扩散模型,能够有效地消除噪声和保持边缘.The key point of research on anisotropic diffusion is to build the adaptive and stable diffusion model. However, there are still two problems in the existing anisotropic diffusion models -- the determination of the gradient threshold and the iterative stopping time. In this paper, we propose a time-dependent robust anisotropic diffusion method. In the method, the Gaussian scale and the gradient threshold are set to the monotonically decreasing function of the time, which is very useful to accurately extract edge and boundary features. Meanwhile, an iterative SNR measure is defined to effectively determine the stopping time, so as to lessen over-smooth regions. In order to show the validity of the proposed diffusion scheme, we use one gray image ＂Pinecone＂ in our experiments. Experimental results have shown that the time-dependent robust anisotropic diffusion methods have superiority over the existing methods and they can effectively smooth out noise while preserving edge features.

关 键 词：各向异性扩散 时间变化 扩散系数 鲁棒 

分 类 号：TP391.41[自动化与计算机技术—计算机应用技术]