摘要本文介绍了微光成像技术的相关概念、微光成像系统的组成及其工作原理，分析了微光成像系统在目标照度很低，目标和背景的反射系数接近等较恶劣的条件下所得微光图像的主要缺点，并应用数字图像处理技术对微光图像做了简单的增强处理。图像增强是数字图像处理的过程中经常采用的一种方法，它对提高图像质量起着重要的作用。本文先对图像增强的原理进行概述，然后对图像增强的方法分类并给出直方图增强、对比度增强、平滑和锐化等几种常用的增强方法的理论基础，通过MATLAB实验得出的实际处理效果来对比各种算法的优缺点，讨论不同的增强算法的技术要点，并对其图像增强方法进行性能评价。66764

毕业论文关键词  图像增强 直方图增强  对比度增强  微光图像    拉普拉斯变换  小波变换

毕业设计说明书（论文）外文摘要

Title    Low-light-level image enhancement methods     

Abstract

In this paper，the concept of LLL imaging technology related  LLL imaging system composition and working principle of the LLL imaging system is  introduced.it analyzes the main drawback of the LLL image obtained by the LLL imaging system in low light conditions, using digital image processing techniques to do a simple shimmer image enhancement processing. Image enhancement is a method often used in digital image processing to improve image quality, it plays an important role. This article first introduces the principle of image enhancement and classification，and then focus on several methods to study such as and histogram enhancement, contrast enhancement, smoothing and sharpening, and other commonly used in learning the basic digital image With the approach, through MATLAB experiment that the actual effect of various algorithms to compare the advantages and disadvantages to discuss the different enhancement algorithm. The application of occasions, and its image enhancement method of performance evaluation.

Keywords   Image Enhancement  Histogram enhancement Contrast enhancement  Low-light-level image  Laplace transform  Wavelet Transform

目  录……3

1.1微光成像技术概述 4

1.2微光成像系统的组成及工作原理 4

1.3 微光图像的特征 5

1.4 微光夜视技术的发展状况 6

2  图像增强技术概论 8

2.1  图像增强背景及意义 8

2.2 图像增强的定义 9

2.3 图像增强的应用 9

3  图像增强基本算法 10

3.1 点运算 10

3.1.1灰度级校正 10

3.1.2 灰度变换 10

3.1.3直方图修正 14

3.2 空域图像平滑 16

3.2.1 噪声消除法 16

3.2.2 邻域平均法 17

3.2.3 中值滤波 18

3.2.4 梯度倒数加权 19

3.3 空间域图像锐化 21

3.3.1 梯度法 21

3.3.2  Laplacian算子 22