双正交小波在陀螺信号去噪中的应用

本文在用双正交小波对陀螺信号进行不同尺度分解的基础上,结合传统的信号分析方法,得出小波系数是由噪声产生的,从而提出合适的小波去噪方法。本方法在应用中得到较好的去噪效果。     

Multiresolution Representation of 2D CSG Models

Multiresolution is currently one of the main schemes used in CAD modeling for representing objects, particularly when large-scale geometric data must be transferred interactively over a network, as in the case of collaborative design. Increasingly complex products and growing competition have turned design into a collaborative team effort. Furthermore, the widespread development of Internet viewers has also necessitated the transfer and display of large-scale CAD models over networks. In order to reduce the volume of transferred data, efforts have been made to transfer CSG (Constructive Solid Geometry) models rather than those based on B_rep (Boundary Representation). This paper presents an original new method for speeding up data transfer by using multiresolution CSG models at different levels of details (LOD). The multiresolution CSG algorithm generates a hierarchy of multiresolution CSG trees; at each level, the shape is further approximated and represented by a smaller number of CSG primitives. The paper analyzes the proposed algorithm, and demonstrates its feasibility.     

Concealed weapon detection and visualization in a synthesized image

Images acquired by heterogeneous image sensors may provide complementary information about the scene, for instance, the visual image can provide personal identification information like the facial pattern while the infrared (IR) or millimeter wave image can detect the suspicious regions of concealed weapons. Usually, a technique, namely multiresolution pixel-level image fusion is applied to integrate the information from multi-sensor images. However, when the images are significantly different, the performance of the multiresolution fusion algorithms is not always satisfactory. In this study, a new strategy consisting of two steps is proposed. The first step is to use an unsupervised fuzzy k-means clustering to detect the concealed weapon from the IR image. The detected region is embedded in the visual image in the second step and this process is implemented with a multiresolution mosaic technique. Therefore, the synthesized image retains the quality comparable to the visual image while the region of the concealed weapon is highlighted and enhanced. The experimental results indicate the efficiency of the proposed approach.This material is based on part of the work carried out at the SPCR laboratory of Lehigh University and the work is partially supported by the U. S. Army Research Office under grant number DAAD19-00-1-0431. The content of the information does not necessarily reflect the position or the policy of the federal government, and no official endorsement should be inferred.     

Spline multiresolution and wavelet-like decompositions

Splines are useful tools to represent, modify and analyze curves and they play an important role in various practical applications. We present a multiresolution approach to spline curves with arbitrary knots that provides good feature detection and localization properties for non-equally distributed geometric data. In addition, we show how equidistributed data and knot sequences can be efficiently handled using signal processing techniques.     

SAR与可见光图象匹配方法的研究

由于SAR和可见光成象传感器图象的物理特征不同,因此进行匹配难度很大。本文在深入分析了这两种传感器图象物理特征的基础上,提出了一种图象匹配的新方法。该方法运用形态学滤波方法去除SAR图象斑点噪声,利用图象的边缘特征进行匹配,并采用多分辨率分级搜索技术减少计算量,在对实验结果进行分析的基础上提出了搜索真实匹配位置的原则,大大提高了匹配的准确率。通过实验对SAR图象斑点噪声滤波和SAR与可见光图象匹配算法进行了验证,实验证明本算法的SAR图象去噪效果明显优于传统的Frost方法,图象匹配精度高,稳定性好。     

一种基于一致性邻域超图模型的图象分割方法

提出了一种将超图理论与图象的空－频域特征分析相结合的图象分割方法,该方法是基于图象的多分辨率小波分析及高斯－马尔可夫随机场理论,在抽取一组反映图象局部空间结构信息的特征矢量基础上,根据同一区域的象素具有相似的特征矢量的原则,将图象转换为一个关于特征相似性测度的领域超图,再利用覆盖－选择算法对该超图进行分割的方法,实验证明,该方法具有较好的稳定性和适应性,尤其对于一些信噪比较低的图象,也具有良好的分     

基于小波的视频镜头自适应分割

随着多媒体技术的发展 ,出现了大量的视频数据 .但由于视频数据是非结构性的 ,因此为了便于视频的检索和浏览 ,必须对视频进行分段 ,而将镜头作为分段的基本单位是比较适合的 .通过仔细分析镜头串接的特点 ,根据小波的特性和小波变换检测奇变点的优点 ,提出了应用小波变换检测视频内容差异度函数奇变点的方法对镜头边界进行检测 .首先取一段视频 ,选取亮度直方图对视频的内容进行描述 ,然后提取视频内容差异度变化曲线 ,再进行多分辨小波分解 ,去噪后找出模极大值点 ,经过跟踪可较准确地找出镜头边界 .实验证明 ,该方法能自适应的对视频进行分割 ,对各种类型的镜头边界有较好的检测效果 .     

基于Matlab 的图像融合方法

利用Matlab的工具箱函数实现数字图像融合。采用手动选取控制点进行图像配准；模拟时域加权函数，提出基于小波变换的归一化Mask方法进行图像融合，体现了时域中不同区域的重要程度。算法易于实现，应用方便。实验表明，融合图像平滑自然。     

基于小波变换的实时影象匹配

讨论了一种基于小波变换的实时影像匹配方法。在多尺度特征提取的过程中，采用了局域正则性指数作为约束条件，保证了特征提取的可靠性；利用小波正交分解与重建实现了分层匹配；同时，采用特征与影像叠加进行了亚像素匹配。经过试验证明，上述方法是行之有效的。