外文翻译---图像的边缘检测

附：英文资料翻译

图像的边缘检测

To image edge examination algorithm research academic report

Abstract

Digital image processing took a relative quite young discipline, is following the computer technology rapid development, day by day obtains the widespread application.The edge took the image one kind of basic characteristic, in the pattern recognition, the image division, the image intensification as well as the image compression and so on in the domain has a more widespread application.Image edge detection method many and varied, in which based on brightness algorithm, is studies the time to be most long, the theory develops the maturest method, it mainly is through some difference operator, calculates its gradient based on image brightness the change, thus examines the edge, mainly has Robert, Laplacian, Sobel, Canny, operators and so on LOG. First as a whole introduced digital image processing and the edge detection survey, has enumerated several kind of at present commonly used edge detection technology and the algorithm, and selects two kinds to use Visual the C language programming realization, through withdraws the image result to two algorithms the comparison, the research discusses their good and bad points.

对图像边缘检测算法的研究学术报告摘要

数字图像处理作为一门相对比较年轻的学科, 伴随着计算机技术的飞速发展, 日益得到广泛的应用. 边缘作为图像的一种基本特征, 在图像识别,图像分割,图像增强以及图像压缩等的领域中有较为广泛的应用.图像边缘提取的手段多种多样,其中基于亮度的算法,是研究时间最久,理论发展最成熟的方法, 它主要是通过一些差分算子, 由图像的亮度计算其梯度的变化, 从而检测出边缘, 主要有Robert, Laplacian, Sobel, Canny, LOG 等算子. 首先从总体上介绍了数字图像处理及边缘提取的概况, 列举了几种目前常用的边缘提取技术和算法,并选取其中两种使用Visual C++语言编程实现,通过对两种算法所提取图像结果的比较,研究探讨它们的优缺点.

First chapter introduction

§1.1 image edge examination introduction

The image edge is one of image most basic characteristics, often is carrying image majority of informations.But the edge exists in the image irregular structure and in

not the steady phenomenon, also namely exists in the signal point of discontinuity place, these spots have given the image outline position, these outlines are frequently we when the imagery processing needs the extremely important some representative condition, this needs us to examine and to withdraw its edge to an image. But the edge examination algorithm is in the imagery processing question one of classical technical difficult problems, its solution carries on the high level regarding us the characteristic description, the recognition and the understanding and so on has the significant influence; Also because the edge examination all has in many aspects the extremely important use value, therefore how the people are devoting continuously in study and solve the structure to leave have the good nature and the good effect edge examination operator question.In the usual situation, we may the signal in singular point and the point of discontinuity thought is in the image peripheral point, its nearby gradation change situation may reflect from its neighboring picture element gradation distribution gradient. According to this characteristic, we proposed many kinds of edge examination operator: If Robert operator, Sobel operator, Prewitt operator, Laplace operator and so on.These methods many are wait for the processing picture element to carry on the gradation analysis for the central neighborhood achievement the foundation, realized and has already obtained the good processing effect to the image edge extraction. . But this kind of method simultaneously also exists has the edge picture element width, the noise jamming is serious and so on the shortcomings, even if uses some auxiliary methods to perform the denoising, also corresponding can bring the flaw which the edge fuzzy and so on overcomes with difficulty.Along with the wavelet analysis appearance, its good time frequency partial characteristic by the widespread application in the imagery processing and in the pattern recognition domain, becomes in the signal processing the commonly used method and the powerful tool.Through the wavelet analysis, may interweave decomposes in the same place each kind of composite signal the different frequency the block signal, but carries on the edge examination through the wavelet transformation, may use its multi-criteria and the multi-resolution nature fully , real effective expresses the image the edge characteristic.When the wavelet transformation criterion reduces, is more sensitive to the image detail; But when the criterion increases, the image detail is filtered out, the examination edge will be only the thick outline.This characteristic is extremely useful in the pattern recognition, we may be called this thick outline the image the main edge.If will be able an image main edge clear integrity extraction, this to the goal division, the recognition and so on following processing to bring the enormous convenience.Generally speaking, the above method all is the work which does based on the image luminance information.