电子科技大学毕业论文

图像JPEG压缩的matlab实现

作者姓名：

专业名称：信息工程

指导教师： 讲师

图像JPEG压缩的matlab实现

摘要

随着现代经济的发展，影像风暴已经席卷了我们的日常生活，图像对于人们已经息息相关。人们对计算机实时处理图像的要求就相对有所提高。现在我们就面对一个问题，如何在保证图像质量的前提下，同时能够考虑到实时性和高效性就成了一个大家关注的问题。那么对图像数据信息进行必要的压缩，以便能够保证图像的快速存储和传输。但是，我们通常看到的图像是一种重要的二维信号，所以它本身就包含非常庞大的数据量，为了快速存储和实时传输，就必须对图像信息进行相应的压缩处理。新兴的数学工具是局域DCT变换是一种新兴的数学工具，在现在社会中，图像压缩技术现在正受到大量的关注与研究。

本次课题设计在分析近年来，在图像处理领域，对图像压缩普遍方法的基础之上，充分学习和分析了基于DCT变换的图像压缩的相关编码及其基本原理和实现步骤。简单概述了图像压缩的基本原理以及发展现状和方向，全面分析了DCT变换算法以及思路，提出了采用DCT变换压缩的依据和优势。本文同时也介绍了图像压缩过程的重要步骤——编码量的方法和原理。为了方便简单,将使用MATLAB2010实现JPEG图像压缩的仿真。

在论文最后，将介绍仿真的过程以及仿真结果说明，阐述用MATLAB来实现离散余弦变换的图像压缩的基本过程，并总结相关方法的优缺点。同时也将充分展示压缩前后的图像，并做相应的比较。

关键词：图像 压缩 DCT matlab仿真

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图像JPEG压缩的matlab实现

Abstract

With the development of modern economy, the storm has swept through the image of our daily life, people have been closely related to the image for the. People's requirements on image real-time processing is relatively improved. Now we face a problem, how to guarantee the quality of the image, at the same time can be old enough considering the real-time and efficiency has become an issue of concern. This information is certain to image compression and processing has become a very important link. However, the image is an important signal, due to the large amount of data, while the storage and transmission of the compressed. New mathematical tools are discrete cosine transform is a new mathematical tool, based on the discrete cosine transform image compression technology is now being a lot of attention and research.

In this paper, based on the analysis of the general methods of image compression in recent years, the basic principles and implementation steps of image compression based on DCT transform are also discussed. In this paper, the principle and development of image compression are introduced briefly, and the DCT transform algorithm is analyzed and compared with other compression methods. The basis of DCT transform compression is proposed. The final step of the image compression process is to encode the quantized image. This. We use MATLAB6.5 to realize the simulation of JPEG image compression.

The simulation results show that using MATLAB to achieve the image discrete cosine transform compression method is simple, fast, small error advantages, greatly improves the efficiency and accuracy of image compression.

Keywords: DCT ,matlab,simulation image, compression

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图像JPEG压缩的matlab实现

目录

图像JPEG压缩的matlab实现 ........................................................ I 摘要 .................................................................................................... I Abstract .......................................................................................... II 目录 ................................................................................................. III 前言 ................................................................................................... 1 1 绪论 ............................................................................................... 3 1.1论文研究背景及意义 ................................................................. 3 1.2 JPEG图像的发展历史及简介 ................................................... 4 1.3 JPEG图像在DCT中压缩的作用 ............................................. 5 1.4 本文研究的主要内容 ................................................................ 6 2 图像压缩编码原理 ....................................................................... 7 2.1 DCT变换的来源 ........................................................................ 7 2.2基于DCT的JPEG图像压缩编码步骤 .................................... 8 2.3图像压缩处理技术基本理论 ..................................................... 9 3 图像压缩的MATLAB实现 ........................................................... 12 3.1离散余弦变换的定义及原理 ................................................... 12 3.2离散余弦变换的算法实现 ....................................................... 13 3.3图形用户界面介绍 ................................................................... 14 3.3.1图像文件读取 ..................................................................... 15 3.3.2图像文件输出 ..................................................................... 16 4 运行结果及分析 ......................................................................... 18 4.1 程序流程图 .............................................................................. 18 4.2 MATLAB仿真结果.................................................................. 19 4.3 实验结果及分析 ...................................................................... 20 总结 ................................................................................................. 23

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图像JPEG压缩的matlab实现

参考文献 ......................................................................................... 25 致谢 ................................................................................................. 26 附件1 图像JPEG压缩的matlab程序 ........................................ 27

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