图像增强技术在安防监控系统中的应用

数字化的图像处理技术里面对于各个综合知识的跨度是相当大的,对于各个知识面的要求也是十分高的。那么图像处理技术在实际的生活应用中也是被广泛运用。随着科技时代的到来,人们对于图像的画质要求更高,所以对于图像处理技术的研发已经是整个行业必须解决的问题。那么在这样一个要求越来越高的情形下,在视频监控行业里面图像处理技术起到了那些作用？是怎么样去应用到安防监控行业里面的？本文针对这些问题作出了一些简单的讨论和研究。     

A new approach for inner-knuckle-print recognition

ObjectiveThis paper proposed a new approach for inner-knuckle-print (IKP) recognition. In traditional IKP recognition systems, the region of interest (ROI) is extracted from the image of the whole hand and the directions of the fingers being imaged are not restricted. The result maybe incorrect because that the shape and surface of the fingers may vary greatly. Moreover, if the direction of the finger being imaged is not restricted, there may be severe rotation transform between intra-class IKPs. To overcome these drawbacks, we develop a new data acquisition scheme as well as an efficient personal authentication algorithm.MethodsThe new scheme is designed to capture the image of the inner surface of the middle knuckles of the middle and ring fingers. The fingers being imaged are kept horizontal with two pegs, so that the rotation angle between different images obtained from the same hand can be minimized. The new personal authentication algorithm consists of the next four steps. Firstly, two regions of interest (ROI), each of which contains the inner surface of a knuckle, are cropped from the original image. Secondly, line features are extracted from the ROIs based on the combination of Gabor filtering and derivative line detection method. Then, binary line images are matched by using a cross-correlation-based method. Finally, the input data is classified through score level fusion.ResultsTo evaluate the proposed IKP recognition system, a finger image database which includes 2000 images from 100 volunteers is established. The images are captured on two separate occasions, at an interval of around two months. Most of the volunteers are not familiar with the image acquisition process. The experimental results show that the proposed system achieves high recognition rate and it works in real time. Moreover, the proposed line feature extraction method outperforms traditional Gabor filter based line detection method and derivative line detection method in accuracy.ConclusionThe proposed IKP system is robust and accurate. It may promote the application and popularization of IKP recognition.     

A new visual cryptography with multi-level encoding

Visual secret sharing (VSS) is a visual cryptography scheme which decodes secret messages into several enlarged shares, and distributes them to different participants. The participants can recover the secret messages by stacking their shares, and then secret message can be revealed by human visual sensitivity. Afterward some researchers start to research size invariant scheme, and apply to encode grayscale images such as scenic photos or pictures, not only binary messages. Owing to the gray values distribution of pictures are different, extreme distribution may cause blurred revealed image. In this paper, we proposed a size invariant VSS scheme which is suitable for different distribution of image's gray values. Experiment results show that the reconstructed images of our method, for brighter, darker, and normal images, have clearer and higher contrast, and without apparent artifact and unexpected contour.     

基于Snake的图像分割算法研究

图像分割算法是指从待割图像中提取出感兴趣的目标,以便进行图像分析与图像理解。Snake算法不同于传统的图像分割方法。文中详细介绍了Snake模型的数学机理及离散化方法,最后利用贪婪法实现了Snake算法,并应用与实际图像的分割。     

桁架结构形状优化的粒子群优化算法

为解决有应力约束、几何约束以及局部稳定性约束的桁架结构的形状优化设计,将粒子群优化(PSO)算法应用于桁架结构的形状优化设计.首先详细介绍了原始PSO算法的基本原理,然后引入压缩因子改进了原始的PSO算法,并提出了合理的参数设置值.优化计算过程中,综合考虑了节点坐标和截面面积等两类不同性质的设计变量.最后对几个经典问题进行了求解,并与传统的优化算法进行了比较.数值结果表明,改进的PSO算法具有良好的收敛性和稳定性,可以有效地进行桁架结构的形状优化设计.     

一种新的融合粒子群算法的混合蟑螂群算法

针对连续蟑螂算法存在初始解质量不高和算法评价次数过多的问题,提出了一种融合了粒子群算法的混合蟑螂群算法并应用于函数优化问题.首先由基本粒子群算法快速收敛到解空间内一个相对优的解,然后由一种改进的蟑螂算法完成全局寻优.仿真结果显示:混合蟑螂算法具有收敛速度快、求解精度高的特点,其算法整体性能优于已存在的连续蟑螂算法.     

人体数字图像中各组织影像的边缘提取算法研究

针对人体数字医学图像中各组织影像界限不明显、图像总体模糊、单个组织影像不均匀等特点,提出一种能够有效提取影像边缘以区分和观察各组织影像的方法。利用计算机图像处理技术,对组织影像进行灰度处理,进而根据不同组织影像的特征,选定相应的阈值,用算法程序对组织影像边缘进行有效提取,得到一系列效果图,通过观察分析得出实验结果。结果表明,该方法能够有效地提取出人体不同组织影像的边缘,有助于医生的临床诊断与分析。     

一种改进的粒子群算法稳定性证明及其应用

针对改进的粒子群算法缺乏理论上稳定性证明及其相应的参数选择问题．利用李雅普诺夫稳定性理论对个体决策粒子群算法给予稳定性证明,并给出相应的参数选择方式,改变传统粒子群算法只能从仿真角度说明该算法的稳定性。采用几个常用的测试函数进行仿真实验,与其他改进的粒子群算法相比,结果表明该算法具有更好的性能。     

互信息在图像检索中的应用

介绍了一种用互信息来衡量相似性图像检索方法.该方法首先生成一种在统计上有代表性的视觉模式,使用这种模式的分布作为图像内容的描述符;基于该内容描述,设计了其互信息的计算方法以衡量图像的相似性.实验结果表明,在图像检索中,相对于其它如KL散度和L2规范等方法,互信息是一种更为有效的衡量相似性的方法.