基于MATLAB的数字图像分割的研究与实现

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题目：

基于MATLAB的数字图像分割的研究与实现学 院：计算机与信息工程学院 学生姓名： 学 号： 专 业： 年 级： 完成日期： 2012年04月 指导教师：

基于MATLAB的数字图像分割的研究与实现

摘要：视觉和听觉是我们认识和感知外部世界的主要途径，而视觉又是其中最重要的，

因此要想更细致、全面地把握这些图像信息就需要对其进行必要的处理。在数字图像处理的研究和应用中很多时候我们只对图像的某些部分和特征感兴趣，此时就需要利用图像分割技术将所需的目标与图片的其他部分区分开，以供我们对图像进一步研究和分析。图像分割即通过一些必要的算法把图像中有意义的部分或特征提取出来，将图像分为若干有意义的区域，使得这些区域对应图像中的不同目标，进而能够对所感兴趣的区域进行研究。基于图像分割技术在图像处理之中的重要性，本研究在此对图像分割的一些经典算法进行了学习和对比，并通过MATLAB对其进行了实验，通过不同的算法对不同的图片进行处理，分析其优缺点，以便在进行图像分割时可以根据图片的特征选择合适的算法。

关键字：数字图像；分割；MATLAB

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The Research and Implementation of Digital Image

Segmentation Based on the MATLAB

Abstract : Vision and auditory are the main ways which we use to understand and

perceive the world outside, while vision is the most important. Therefore, it's require to process the image data to grasp them more painstaking and completely. In digital image processing of research and application we are only interested to some parts of the image and characteristic in many times, then you need to use the image segmentation technology to separate the goal and the picture for other parts for our further research and analysis of the image.Image segmentation is dividing the image into some significant areas through some necessary algorithms, then make these areas corresponding to different goals and we can do some research about the areas we are interested to. Based on the importance of image segmentation technology in image processing, I compared several classical algorithms of image segmentation. In the meanwhile, I used the MATLAB to do some research and to process the various images with different algorithms so that it's convinent to find the advantages of these algorithms. Then, I can base on the characteristics of the images to choose the suitable algorithms when to make some digital image segmentation.

Key words : Digital Image; Segmentation; MATLAB

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目 录

1 绪论...................................................................................................................................... 1

1.1 图像分割的研究背景................................................................................................ 1 1.2 图像分割的基本原理................................................................................................ 1 2 图像处理与MATLAB ........................................................................................................ 2

2.1 MATLAB处理的图像格式与类型 ........................................................................... 2 2.2 MATLAB的界面 ....................................................................................................... 3 2.3 MATLAB图像的基本操作 ....................................................................................... 5 2.3.1 图像文件信息的查询 ......................................................................................... 5 2.3.2 图像文件的读取 ................................................................................................. 5 2.3.4 图像文件的写入 ................................................................................................. 5 2.3.5 MATLAB图像工具箱中的图像显示函数 ........................................................ 6 3 阈值化分割.......................................................................................................................... 7

3.1 双峰法........................................................................................................................ 7 3.1.1 数学推导 ............................................................................................................. 7 3.1.2 双峰法图像分割示例 ......................................................................................... 7 3.2 自动选择法................................................................................................................ 9 3.2.1 自动选择法推导过程 ......................................................................................... 9 3.2.2 迭代法图像分割 ............................................................................................... 10 3.2.3 最大类间方差法图像分割 ............................................................................... 10 4 区域化分割........................................................................................................................ 11

4.1 区域生长分割算法.................................................................................................. 11 4.1.1 区域生长法简介 ............................................................................................... 11 4.1.2 区域生长法的MATLAB程序与分割操作 .................................................... 12 4.2 分裂合并分割算法.................................................................................................. 14 4.2.1 分裂合并分割算法简介 ................................................................................... 14 4.2.2 分裂合并法的MATLAB程序与分割操作 .................................................... 15 5 图像分割算法的评价........................................................................................................ 16

5.1 图像分割算法评价概述.......................................................................................... 16 5.2 图像分割算法评价方法和要求.............................................................................. 16

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