高分辨电子显微像的定量分析与应用I.基于图像处理的高分辨像定量分析方法

本文通过研究高分辨电子显微像的图像处理技术,系统地建立了两种高分辨原子像亮点中心精确定位的处理方法:灰度梯度检测法和峰谷提取-灰度平均法.基于原子像亮点中心定位技术,使用最小二乘法,建立了测量高分辨像中局部点阵参数和晶格畸变的实际处理过程.结合像模拟、图像匹配等手段,详细研究了从高分辨像中提取元素分布、原子结构等信息的定量分析方法;并建立了一套UNIX平台上的高分辨像定量分析程序包,具有较高的精度和广泛的用途.     

合成孔径雷达图像舰船目标检测与分析

舰船检测是合成孔径雷达图像海洋应用的一个重要部分。本文设计了舰船检测步骤，给出了SAR图像舰船形状分析的方法，对于舰船目标进行自动检测并计算出舰船参数，通过实验验证目标的检测与分析是有效的。     

SAR图像组合降斑算法

SAR图像存在较强的相干斑点噪声,严重的影响了地物信息的提取与SAR图像的应用效果,作者在研究分析斑点噪声产生机理以及统计特性的基础上,提出了一种组合降斑重构算法,该算法与降斑重构性能优异的模拟退火算法降斑重构性能相当,但极大的减少了计算代价;与许多其它SAR降斑算法相比,组合降斑重构算法具有很好的降斑以及场景结构保持性能,并有较好的实用性.     

SAR图像的自动分割方法研究

由于存在相干斑噪声的影响,给SAR图像分割造成很大的困难,该文提出了一种SAR图像的自动分割方法。首先在特征提取阶段,通过计算小波能量提取纹理信息,用邻域统计量提取灰度信息,用保边缘平均灰度提取边缘信息,以确保边缘准确。然后提出一种改进的完全无监督的聚类算法进行图像分割,该算法可以自动确定分割的类型数目。由于该方法充分考虑了SAR图像的纹理、灰度和边缘信息,因而极大地提高了其最终分割性能。实验结果证明了该方法的有效性。     

SAR图像组合分割算法

由于存在乘性斑点噪声的影响,给SAR图像分割造成很大困难,本文研究利用最大似然区域增长分割算法,提出区域增长前引入自适应边缘检测,图像分割性能获得较大提高.介绍了我们研究的分割性能优异的模拟退火分割算法,提出了分割性能接近模拟退火并且在SAR图像分割中比较实用的模拟退火和最大似然混合分割算法,并给出了这些分割算法的分割性能比较,以及在实际分割SAR图像时应当如何选择分割算法.     

Methods for Displaying Three-Dimensional Images

The essential components of generating three-dimensional (3-D) images are defined, and various methods of creating each of the components are explained. The components are image acquisition, image multiplexing and processing, and display mechanisms. For image acquisition, transforming, synthesizing based on disparity, voxel and wavefront deformation, and sampling and photographing methods are used. For multiplexing, time, spatial, and spatiotemporal, and for processing, chirping, layering, and pixel cell based multiview image arrangement methods are used. The display mechanisms are classified into projection, contact,and scanning types depending on their means of displaying images. From these methods, 3-D images with real volume, with parallax only and with psychologically induced depth sense can be generated. The display mechanisms have another important mission of creating viewing zones. For this purpose, all 3-D imaging methods employ a special form of optics or mechanisms complying with their image multiplexing schemes. These optics and mechanisms are essential in realizing 3-D imaging systems but at the same time they provide many unfriendly and uncomfortable effects to viewers, and also impose some functional limitations.     

Design and Analysis of High-Throughput Lossless Image Compression Engine Using VLSI-Oriented FELICS Algorithm

In this paper, the VLSI-oriented fast, efficient, lossless image compression system (FELICS) algorithm, which consists of simplified adjusted binary code and Golomb–Rice code with storage-less $k$ parameter selection, is proposed to provide the lossless compression method for high-throughput applications. The simplified adjusted binary code reduces the number of arithmetic operation and improves processing speed. According to theoretical analysis, the storage-less $ k$ parameter selection applies a fixed $ k$ value in Golomb–Rice code to remove data dependency and extra storage for cumulation table. Besides, the color difference preprocessing is also proposed to improve coding efficiency with simple arithmetic operation. Based on VLSI-oriented FELICS algorithm, the proposed hardware architecture features compactly regular data flow, and two-level parallelism with four-stage pipelining is adopted as the framework of the proposed architecture. The chip is fabricated in TSMC 0.13-$ mu$m 1P8M CMOS technology with Artisan cell library. Experiment results reveal that the proposed architecture presents superior performance in parallelism-efficiency and power-efficiency compared with other existing works, which characterize high-speed lossless compression. The maximum throughput can achieve 4.36 Gb/s. Regarding high definition (HD) display applications, our encoding capability can achieve a high-quality specification of full-HD 1080p at 60 Hz with complete red, green, blue color components. Furthermore, with the configuration as the multilevel parallelism, the proposed architecture can be applied to the advanced HD display specifications, which demand huge requirement of throughput.      

SILEX检测与验证

评述了首次实现星问光学连接的欧洲空间局(ESA)的SILEX计划的检测与验证方法,相信对我国星间光通信技术的研究与发展具有一定的促进作用。     

Patch-Based Nonlocal Functional for Denoising Fluorescence Microscopy Image Sequences

We present a nonparametric regression method for denoising 3-D image sequences acquired via fluorescence microscopy. The proposed method exploits the redundancy of the 3-D+time information to improve the signal-to-noise ratio of images corrupted by Poisson-Gaussian noise. A variance stabilization transform is first applied to the image-data to remove the dependence between the mean and variance of intensity values. This preprocessing requires the knowledge of parameters related to the acquisition system, also estimated in our approach. In a second step, we propose an original statistical patch-based framework for noise reduction and preservation of space-time discontinuities. In our study, discontinuities are related to small moving spots with high velocity observed in fluorescence video-microscopy. The idea is to minimize an objective nonlocal energy functional involving spatio-temporal image patches. The minimizer has a simple form and is defined as the weighted average of input data taken in spatially-varying neighborhoods. The size of each neighborhood is optimized to improve the performance of the pointwise estimator. The performance of the algorithm (which requires no motion estimation) is then evaluated on both synthetic and real image sequences using qualitative and quantitative criteria.      

State Space Realization of a Three-dimensional Image Set with Application to Noise Reduction of Fluorescent Microscopy Images of Cells

A method is presented to calculate state space realizations of a three-dimensional image set. It is based on interpreting the image set as the impulse response of a 3D separable system. As an application it is shown how this method, combined with approximation steps, including balanced model reduction, can be used to suppress noise in three-dimensional image sets. The approach was motivated by a practical problem in the analysis of three-dimensional fluorescent microscopy image data of fluorescently labelled cells. The method is illustrated by an analysis of simulated data and experimental data. The proposed approach can also be applied to a two-dimensional image in a straightforward way.Received July 9, 2003; Revised April 20, 2003; Accepted June 11, 2004; First online version published in December 2004     

Characterization of Geoinspired and Synthetic Chrysotile Nanotubes by Atomic Force Microscopy and Transmission Electron Microscopy

Geoinspired synthetic chrysotile nanotubes both stoichiometric and 0.67 wt % Fe doped were characterized by transmission electron microscopy and electron diffraction. Bending tests of the synthetic chrysotile nanotubes were performed using the atomic force microscope. The nanotubes were found to exhibit elastic behaviour at small deformations (below ca. 20 nm). Young's modulus values of (159 ± 125) GPa and (279 ± 260) GPa were obtained from the force‐deflection curves using the bending equation for a clamped beam under a concentrated load, for the stoichiometric and the Fe doped chrysotile nanotubes, respectively. The structural modifications induced by Fe doping altered the mechanical properties, with an apparent dependence of the latter on the number of constituting walls of the nanotubes.     

Runlength-Based Processing Methods for Low Bit-depth Images

Many low bit-depth images are compactly expressed in terms of runlength-based representations. This paper discusses methods for processing such images directly in runlength-represented form and how this can improve processing times for image processing operations. The primary focus in the analysis is on image compression operations, but an explanation of the overall scheme for runlength-based processing is also presented. Tradeoffs between processing times and compression ratio for runlength-based image compression algorithms are discussed. Sketches of runlength-based compression algorithms for some widely used image standards are given, and the algorithms are compared with raster-based counterparts. Important design features needed in implementations of runlength-based image processing are discussed. The main application areas of runlength-based image processing are also explained.      

二维图像放大方法的熵分析

对最近邻插值法、线性插值法、邻域像素交换法3种二维图像放大方法的熵进行了分析,给出了放大到4倍和9倍时的计算方法,并对误差进行了分析,仿真结果证明了所给方法的有效性,并发现线性插值法要好一些。     

一种SAR图像的自动匹配算法及实现

合成孔径雷达(SAR)图像的匹配处理是SAR图像后处理及应用的重要环节。该文提出了一种基于图像特征的快速匹配实现方法。针对两幅SAR图像,该方法进行边缘检测和区域轮廓提取以及区域特征描述,最后实现图像的自动匹配。利用真实SAR图像进行了试验,获得很好的试验结果。     

图像边缘检测方法分析与研究

边缘是图像的重要特征,边缘检测在计算机视觉、图像分析等应用中起着重要作用,是图像目标检测中一个基础而又困难的问题,本文分析了常规的边缘检测方法及其特点,并用这些方法分别对原始图像和噪声图像进行了处理,处理的结果表明,Sobel、Roberts、Prewitt、Kirsch、LOG算子的图像处理效果各有利弊,它们在定位精度、噪声敏感度和复杂度之间存在互相抑制的关系。     

空时被动合成孔径阵列处理算法研究

本文介绍了两种被动合成孔径阵列处理算法。第一种算法是通过空时数据的互协方差矩阵估计,来精确估计相位校正因子,以提高孔径合成性能;另一种是在前一种算法基础之上,利用对信号子空间的低秩近似来提高低信噪比环境下相位校正因子的估计性能,从而提高被动合成孔径性能的算法。通过对仿真数据和实验数据的分析和比较,说明这两种新算法在较低信噪比下可以得到比传统的ETAM和后来的时域ETAM算法更好的相位估计与方位分辨性能和信号增益。     

一种提高结核菌痰涂片显微图像质量方法

通过痰涂片镜检法检测结核抗酸杆菌,是识别和诊断结核病的一种快速、价廉和特定的检测方法.为提高结核病痰涂片显微图像的质量,提出了一种基于多帧不同曝光图像信息融合,扩展被检测显微图像的动态范围,提高检测视野显微图像质量的实现方法.首先在保持CCD曝光时间不变的条件,通过计算机控制圆盘型光学梯度衰减片旋转定位的方法,摄取同一视场多帧不同曝光量的显微图像序列,从而获取场景的高动态范围显微图像信息.然后利用拉普拉斯金字塔算法将显微图像进行分层,采用图像梯度与信息熵相结合对层次图像进行评价,分配相应的合成权重系数,并用拉普拉斯金字塔逆算法,合成一帧高质量的图像.实验表明,所提出方法能有效地表达亮区和暗区的场景信息,增强图像的细节特征,提高痰涂片显微成像的质量,有利于提高显微图像智能检测的精度.     

A Two-Dimensional Bandwidth Extrapolation Technique for Polarimetric Synthetic Aperture Radar Images

The resolution of a synthetic aperture radar (SAR) image, in range and azimuth, is determined by the transmitted bandwidth and the synthetic aperture length, respectively. Various superresolution techniques for improving resolution have been proposed, and we have proposed an algorithm that we call polarimetric bandwidth extrapolation (PBWE). To apply PBWE to a radar image, one needs to first apply PBWE in the range direction and then in the azimuth direction, or vice versa . In this paper, PBWE is further extended to the 2-D case. This extended case (2D-PBWE) utilizes a 2-D polarimetric linear prediction model and expands the spatial frequency bandwidth in range and azimuth directions simultaneously. The performance of the 2D-PBWE is shown through a simulated radar image and a real polarimetric SAR image