一种改进的快速矢量中值滤波器

提出了一种改进的快速矢量巾值滤波器(IFIVF,improved fast impulsive vector filter).IFIVF以FIVF为基础,通过peer group和边缘检测技术构建新的噪声检测器.与其它矢量中值滤波器(VMF)相比,新的噪声检测方法使得IFIVF不但可以对彩色图像中的随机和固定脉冲噪声进行有效压制,还可以进一步提高FIVF的滤波视觉效果.     

基于噪声估计的自适应开关型中值滤波器

提出了一种基于噪声估计的自适应开关型中值滤波器(IASMNE,improved adaptive switching median filter based on noise estimation)。IASMNE以图像经小波变换后在不同尺度和不同方向提取的子带滤波系数值的统计信息构成刻画图像受噪声干扰程度的特征矢量,在大量噪声图像上获得的特征矢量为学习数据集,并利用支持向量回归(SVR)分析实现对图像中噪声比例的准确估计。基于此,IASMNE对高、中、低不同噪声比例图像启动不同的滤波策略,并灵活设置滤波参数。大量实验表明,与其它开关型滤波器相比,IASMNE能够合理地根据图像噪声干扰程度进行最佳滤波,尤其是对于大于70%的椒盐噪声(SPN)能够大幅度提高图像质量。     

一种用于光谱图像的基于邻域背景检测的矢量滤波器

提出了一种通用性强的非线性矢量数字滤波器———基于邻域背景统计的矢量滤波器,该滤波器既可用于光谱图像又可用于灰度图像,具有腐蚀小面积奇异像元的作用,可以消除图像噪声和光谱散点,同时保持原有的光谱信息不变,此外还对图像边缘有一定的锐化作用.文章设计了该滤波器的一种简化实现算法,并给出了航空高光谱图像和彩色图像的处理实例,实验结果显示该滤波器滤波效果良好,对光谱图像的噪声消除和边缘检测都有很大帮助.     

实时图象的伪中值滤波和sobel边缘增强

本文主要研究中值滤波器和Sobel算子的滤波性能,并采用流水线方式硬件实现了伪中值滤波和Sobel边缘增强。两种方法均可以实时地滤除图象中的噪声,并勾画出边缘。处理后图象信噪比可提高约7dB,输出延迟小于200μs。此外,本文还提出一种新的噪声乎滑方法。该方法与中值滤波器一样可以保护图象边缘,滤除脉冲颗粒噪声,而且,它抑制随机噪声的效果优于中值滤波器。     

复合滤波在三维电子罗盘输出数据处理中的应用

三维电子罗盘在长距离数据传输过程中,将受到外界噪声的干扰。该噪声不仅含有高斯噪声,还含有脉冲噪声。介绍一种抑制噪声干扰的复合数据滤波方法,即先利用一种非线性滤波器——中值滤波器,消除脉冲噪声,然后再利用FIR低通滤波器,对其进行平滑处理。与传统的直接采用线性滤波器的滤波结果相比较,该方法的滤波效果更为理想。     

一种基于中值-模糊技术的混合噪声滤波器

结合中值与模糊滤波技术,提出了一种新的图像混合噪声滤波算法。算法将受混合噪声污染的图像分为脉冲噪声点集与含有高斯噪声的像素点集两部分,首先进行灰度极值检测,进而借助邻域纹理信息准确检测出脉冲噪声,并以中值滤波滤除;对于含有高斯噪声的像素点则采用一种保护细节的模糊滤波器进行处理。实验结果说明算法不仅能有效地滤除脉冲与高斯混合噪声,而且可以较好地保护图像细节。     

基于图像内容的中值滤波器设计及其FPGA实现

在图像处理领域里,中值滤波器经常用于去除图像的椒盐噪声。传统的中值滤波器存在图像模糊的缺陷。本文介绍了一种新的中值滤波器的结构,该滤波器首先检测图像是否存在噪声,然后决定是否进行中值滤波。因此该滤波器在去除图像噪声的同时,比传统的中值滤波器更好地保留了图像细节。     

噪声图象滤波的稳健混合M滤波器

本文提出一种在空间域根据采集图象局部统计特性和相关信息进行噪声滤波算法─稳健混合M型滤波器．该滤波算法不仅能有效地抑制各种图象噪声分量，而且克服线性滤波算法引起的边缘模糊和细节损失，保持图象边缘和几何结构。选择中值做参考信号有效地改善图象的信噪比和对比度，使滤波后图象具有良好的视觉效果．同CS滤波器、HDMF滤波器、DWMTMF滤波器、自适应L滤波器性能相比较，本文提出的方法在滤波、边缘保持等方面有突出的优点。     

基于方向信息测度的自适应多级中值滤波器

针对图像滤噪中滤除噪声和保护细节(边缘)的矛盾,本文提出一种新的基于方向信息测度的自适应多级中值滤波器。方向性是边缘和噪声的本质区别之一,通过基于方向信息测度所构造的自适应结构,决定中值滤波器的形式和滤波窗口尺寸的大小,而不需要图像和噪声的先验知识。文章比较了标准中值滤波器、单向多级中值滤波器、双向多级中值滤波器和本文方法的结果。实验表明本文方法具有更好的效果。     

使用新型中值滤波器检测和消除图像的脉冲噪声

本文提出了使用适应性、可变化窗口尺寸的新型递归加权中值滤波器来消除彩色图像中的脉冲噪声的方法。对于图像存在的噪声密度,递归加权中值滤波器的窗口尺寸是自适应、窗口可调节的。与传统的脉冲噪声滤波器相比,新型滤波器具有良好的脉冲噪声抑制与图像细节边缘保护的性能。     

基于三边滤波的Retinex图像去雾算法

针对传统Retinex算法采用高斯滤波估计图像的照射分量易产生边缘模糊,不能有效去除脉冲噪声且处理后的图像颜色易失真等问题,提出一种基于三边滤波的Retinex图像去雾算法。该算法利用三边滤波器估计图像的照射分量,三边滤波器继承了双边滤波器既可以有效降低图像加性高斯噪声又可以保持图像边缘细节的特性,同时又解决了双边滤波器与高斯滤波器不能有效滤除脉冲噪声,易产生伪边缘等问题。为验证该算法的有效性,采用5种不同的客观评价参数对处理后的图像进行评价。实验证明,该算法能有效地改善雾天图像的退化现象,提高图像的清晰度。     

A fuzzy noise reduction method for color images.

A new fuzzy filter is presented for the reduction of additive noise for digital color images. The filter consists of two subfilters. The first subfilter computes fuzzy distances between the color components of the central pixel and its neighborhood. These distances determine in what degree each component should be corrected. All performed corrections preserve the color component distances. The goal of the second subfilter is to correct the pixels where the color components differences are corrupted so much that they appear as outliers in comparison to their environment. Experimental results show the feasibility of the proposed approach. We compare with other noise reduction methods by numerical measures and visual observations. We also illustrate the performance of the proposed method as preprocessing step for edge detection.     

Quaternion switching filter for impulse noise reduction in color image

A novel approach to impulse noise reduction in color image is introduced in this paper. By applying the quaternion unit transform theory, the difference between two color pixels can be represented in the quaternion form. Based on the difference mentioned above, an efficient filter that can switch between the vector median filter (VMF) and the identity filter (no filtering operation) is proposed. Extensive simulation result indicates that the proposed filter achieves a trade-off between noise suppression and detail preservation in both correlated and uncorrelated impulse noise scenarios when compared with other widely used filters. Furthermore, the computational complexity analysis shows that the proposed filter is quite efficient.     

基于神经网络噪声检测的自适应中值滤波器

针对椒盐噪声污染图像的滤波问题,提出了一种基于前馈神经网络的噪声检测器。基于这种噪声检测方法,采用自适应中值滤波算法,依据像素点的不同属性采用不同的滤波策略。实验结果表明,该算法在有效去除椒盐噪声的同时更好地保留了图像的边缘和细节,是一种有效的图像去噪方法。     

彩色形态滤波器分析

形态滤波属于非线性信号变换处理,它利用信号的局部特征对信号进行修正。最近的研究表明形态滤波器能有效地滤除二值图像及灰度图像中的噪声,本文引入了建立在ＲＧＢ彩色空间上的彩色形态变换,针数字形态学理论从灰度空间扩展到彩色空间,对基本彩色形态滤波器（即彩色形态闭、开）及以它们为基础所构造出一些复杂的彩色形态滤波器进行了研究,并对它们选用不同结构元素的情况进行了分析,实验表明彩色形态滤波器能直接有效地消除     

A robust structure-adaptive hybrid vector filter for color image restoration.

A robust structure-adaptive hybrid vector filter is proposed for digital color image restoration in this paper. At each pixel location, the image vector (i.e., pixel) is first classified into several different signal activity categories by applying a modified quadtree decomposition to luminance component (image) of the input color image. A weight-adaptive vector filtering operation with an optimal window is then activated to achieve the best tradeoff between noise suppression and detail preservation. Through extensive simulation experiments conducted using a wide range of test color images, the filter has demonstrated superior performance to that of a number of well known benchmark techniques, in terms of both standard objective measurements and perceived image quality, in suppressing several distinct types of noise commonly considered in color image restoration, including Gaussian noise, impulse noise, and mixed noise.     

Color-scale morphological filters with multiple structuring elements

With the wide use of color in many areas, the interest on the color perception and processing has been growing rapidly. An important topic in color image processing is the development of efficient tools capable of filtering images without blurring them and without changing their original chromatic contents. In this paper, a new technique reducing noise of color image is developed. A class of color-scale morphological operations is introduced, which extend mathematical morphology to color image processing, representing a color image as a vector function. The correlation between color components is utilized to perform noise removal. Color-scale morphological niters with multiple structuring elements (CSMF-MSEs) are proposed. Their properties are discussed and proved. Experimental results show that CSMF-MSEs are suitable and powerful to eliminate noise and preserve edges in color image because of efficient utilization of inherent correlation between color components, and they perform better than vector med     

基于噪声分离和小波阈值自适应图像去噪算法

针对VisuShrink小波阈值滤波算法的不足和混合噪声的情况,提出了一种基于噪声分离和尺度的自适应混合图像去噪算法.算法首先通过极值检测分离脉冲噪声和高斯噪声,然后分别对脉冲噪声应用多窗口中值滤波及高斯噪声应用基于尺度的小波阈值滤波完成去噪.实验表明,该混合滤波算法能有效去除图像中的脉冲噪声和高斯噪声,并较好地保存了...     

Difference-type noise detector for adaptive median filter

Noise detection-based median filters have been widely applied to impulse noise reduction. However, the number of pixels misclassified is obviously increased in high noise density. To overcome such drawback, a difference-type noise detector is proposed. In image filtering, a noise detection-based adaptive median algorithm is presented. Experimental results show that the proposed filter can well remove the impulse noise and preserve more details of original images.     

基于同态滤波与自适应模糊多级中值滤波级联算法的散斑噪声污染图像恢复

提出了一种用于恢复散斑噪声污染图像的同态滤波与自适应模糊多级中值滤波级联算法 ,计算机仿真实验结果表明它既保持了图像的几何结构 ,又有效地抑制了散斑噪声 ,并且通过比较证明它优于同态滤波与多级中值滤波级联算法