MATLAB中图像增强技术的实现

摘要I摘要图像增强是指依据图像所存在的问题，按特定的需要突出一幅图像中的某些信息，同时，削弱或去除某些冗余信息的处理方法。其主要目的是使得处理后的图像对给定的应用比原来的图像更加有效同时可以有效的改善图像质量。图像增强技术主要包含直方图修改处理、图像平滑化处理、图像尖锐化处理和彩色处理技术等。图像增强单纯从技术上可分成两大类：一类是频域处理法；一类是空域处理法。频域处理法的采用的是卷积定理，它利用修改图像傅立叶变换的方法实现对图像的增强处理；空域处理法则是对图像中的像素进行直接的处理，大多数是以灰度映射变换为基础的，所用的映射变换取决于增强的目的。在本论文中，利用Matlab提供的若干函数，用于图像类型的转换。Matlab支持五种图像类型，即二值图像、索引图像、灰度图像、RGB图像和多帧图像阵列。在Matlab中要查询一个图像文件的信息，只要用imfinfo指令加上文件及其完整路径名即可。Matlab提供了两个重要的用于图像文件的读写的指令，分别是从图像文件中读取数据的imread，以及将数据写入到图像文件中的imwrite。至于多个图像的显示，则可分为两个方面：在不同的图形窗口显示不同的图像，可以用figure指令来实现；在同一个图形窗口显示多图，可以用subplot来实现。关键字：matlab图像增强灰度滤波器AbstractIIAbstractTheimageintensificationisrefersspecificlyaccordingtoneedstohighlightinanimagecertaininformations,simultaneously,weakenstheinformationprocessingmethodwhichorremovescertaindoesnotneed.Afteritsmainpurposeistheprocessingimageismoreeffectivethantocertainspecificapplicationstheoriginalimage.Theimageintensificationtechnologymainlycontainshistogramrevisionprocessing,imagesmoothprocessing,imageintensificationprocessingandthecoloredprocessingtechnologyandsoon.Theimageintensificationtechnologybasicallyseparablebecomestwobigkinds:Onekindisthefrequencyrangeprocessinglaw,onekindistheairzoneprocessinglaw.Thefrequencyrangeprocessingmethodfoundationconvolutesthetheorem.ItusestherevisionimageFouriertransformationthemethodrealizationtoimageenhancementprocessing.Imageofpointoperations,pointoperationswillentertheimagemapfortheoutputimage,outputimageeachpixelgrayvalueonlybythecorrespondinginputpixelvaluedecision.Nonlinearpointoperationscorrespondtonon-linearmappingfunction,mapping,includingthesquareofthetypicalfunctions,logarithmicfunctions,theinterceptionfunction(windowfunction),field-valuedfunctions,suchasmulti-valuequantizationfunction.Thresholdprocessingisthemostcommonpointofanonlinearoperator,itsfunctionistoselectathresholdvalue,theimagebinarization,andthenusetheresultingbinaryimageforimagesegmentationandedgetrackingprocessing.Keyword:theimageintensificationofmatlab、gray、filter、武汉科技大学中南分校大学毕业论文III目录摘要...................................................................................................................IABSTRACT.............................................................................................................II目录.................................................................................................................III第一章绪论.........................................................................................................5第二章MATLAB的简介....................................................................................62.1MATLAB主要功能...........................................................................................62.2MATLAB优势...................................................................................................72.2.1工作平台和编程环境..............................................................................72.2.2实用的程序语言......................................................................................72.2.3计算机数据处理能力..............................................................................72.2.4图形处理功能..........................................................................................82.2.5应用的模块集合工具箱..........................................................................82.3MATLAB函数与数据类型................................................................................82.3.1整型..........................................................................................................92.3.2浮点数......................................................................................................92.3.3字符..........................................................................................................92.3.4常用的字符操作函数..............................................................................92.4MATLAB常用工具箱.......................................................................................102.5小结................................................................................................................10第三章MATLAB图像增强...............................................................................123.1图像增强技术概述.......................................................................................123.1.1空域滤波增强........................................................................................123.1.2平滑滤波器............................................................................................123.1.3中值滤波器............................................................................................133.1.4锐化滤波器............................................................................................143.1.5低通滤波器............................................................................................143.1.6高通滤波器............................................................................................153.1.7同态滤波器............................................................................................15IV3.2MATLAB图像增强函数....................................................................