摘要局部直方图均衡化在水下图像中的应用研究随着人类对海洋的开发持续增进，探索不断加深，水下图像作为获取水下信息的重要手段已在各个领域发挥着越来越重要的作用。然而由于自然光在水中的吸收和散射，人工光源照度不均匀和移动产生阴影等原因，水下图像往往会存在对比度低、细节模糊、噪声突出等问题。因此，水下图像处理技术应运而生，并得到了飞速发展。直方图均衡化是图像处理领域中利用直方图对图像对比度进行调整的方法。全局直方图均衡化是对图像中各像素点进行统一处理，而局部直方图均衡化则是基于图像局部范围，相比较而言更能突出细节。将直方图均衡化方法应用于水下图像的处理中，可以实现图像增强，提供直观、清晰、适于分析的图像，更加符合人类的视觉特性和机器的识别要求。66237

毕业论文关键词： 水下图像 对比度 直方图 均衡化 

毕业设计说明书（论文）外文摘要

Title    Applied Research of Local Histogram Equalization in  Improving Underwater Images                                                

Abstract

With the constant development and exploration of the ocean，underwater images play an increasingly significant role as a vital means of access to obtain underwater data in all aspects. However, owning to the absorption and scattering of natural light, and the lighting uneven and mobile shadow of artificial light in the water, underwater images often present low contrast, fuzzy details, loud noise and other issues. Therefore,   underwater image processing technology comes into being, and has been rapidly developed. Histogram equalization is a method of image processing using image histogram to adjust the contrast. Global histogram equalization is carried out to process each pixel in the image uniformly, while local histogram equalization is based on the local scale, with better highlight detail in comparison. To conclude, by applying the histogram equalization method to underwater image processing, the images can be enhanced to be more intuitive, clear and analyzable, more in line with the human visual characteristics and machine identification requirements. 

Keywords: Underwater Images, Contrast, Histogram Equalization

目   次

1 绪论 1

1.1  课题研究的背景和意义 1

1.2 国内外发展现状 2

1.3 论文结构和内容安排 3

2 水下图像处理技术 4

2.1 水的光学特性 4

2.1.1 水对光的吸收特性 5

2.1.2 水对光的散射特性 6

2.2 空域图像处理 8

2.2.1 灰度变换 8

2.2.2 直方图均衡化和规定化 9

2.2.3 空域滤波 10

2.3 频域图像处理 12

2.3.1 低通滤波 12

2.3.2 高通滤波 13

2.3.3 同态滤波 14

2.4 图像质量评价